2nd International Symposium on Disaster Resilience & Sustainability Development

DRSD21_119 Control on Seismic Response due to Stiffness Irregularity by Active Tendons using Genetic Algorithm Faisal Ahmad Rather*, Mehtab Alam [email protected] ABSTRACT Seismic control system can be active, passive, semi-active, or hybrid depending upon the mechanism used to control the response of a structure. In active control, algorithms like Pole Placement technique, Linear Quadratic Regulator (LQR) etc. are in vogue. The present research uses LQR to investigate the stiffness irregularity effect on number of actuators driven prestressed tendons and their locations governed by signal generated through LQR algorithm. The optimal number and position of the tendons are obtained through Multi- Objective optimization using Genetic Algorithm. The base shear and number of tendons are the objectives which have been minimized while the constraints are maximum floor displacement and peak story drift. For numerical purpose, a ten-story deficient reinforced cement concrete shear building frame excited by El Centro earthquake is considered. To introduce stiffness irregularity, 1st and 10th story have been identified by maximizing each of the three uncontrolled responses namely maximum floor displacement, peak story drift, and base shear by considering the four values of stiffness modification factors as 0.5, 0.3, 0.2, and 0.125. The number and position of the tendons needed in the irregular frame for the corresponding reduction of base shear as in the regular deficient reference frame with allowable response of the structure as per IS 1893 (part I):2016 depends on both the location of the stiffness irregularity and modification factor. Results to minimize base shear constraining maximum floor displacement and peak story drift, optimal number of tendons, their locations obtained for each of the modification factors considered in critical story are found out and discussed. Structural designers may find application of the analysis to economize the cost of steel reinforcement of the building vis-à-vis active tendons by selecting percentage reduction of base shear. Keywords: Stiffness Irregularity, Active Tendon System, Genetic Algorithm, Seismic Control, Linear Quadratic Regulator 90 | P a g e

DRSD21_213 Deep learning neural network-based landslide susceptibility model for southern tip of Deccan Plateau, India Achu A L*, Girish Gopinath [email protected] ABSTRACT Accurate and reliable landslide susceptibility modelling is essential for regional landslide risk assessment and mitigation. In the present study, a spatially explicit deep learning neural network-based landslide susceptibility model for Wayanad district of Kerala state in India has been developed. The Wayanad was severely affected by devasting landslides during 2018 extreme climatic event and absence of an accurate landslide susceptibility model caused extensive causalities. A geospatial database was developed using 263 previous landslides and twelve geo-environmental variables such as lithology, soil texture, land use/ land cover, slope angle, slope aspect, topographic wetness index, distance from the road, distance from the streams, distance from the lineaments, convergence index, profile and plan curvatures were used for susceptibility modelling. The present investigation used search grid to obtain best hyper tuning parameters and training data is split for 25-fold cross validation. Subsequently the best model is chosen based on minimal log loss and maximum area under curve values (AUC) value for final prediction. The results are validated with receiver operating characteristics curve with AUC (ROC-AUC) and confusion matrix-based parameters. The deep learning neural network model shows 90% (AUC=0.90) accuracy in training frame and 88% accuracy in validation frame. The proposed model is trust-worthy and can be used for future hazard mitigation and land use planning in the study area. Keywords: Landslide, Deep Learning Neural Network, GIS, Wayanad, India 91 | P a g e

DRSD21_189 Integrated Rapid Visual Screening and Vulnerability Assessment for Seismic Hazard, Yangon, Myanmar Hnin Ei Win*, Saw Zaw [email protected] ABSTRACT The study of buildings vulnerability against seismic hazard is the primary objective of this paper. Since Myanmar is situated in one of the earthquake prone zones, the potential hazardous impact questions the quality and performance of existing buildings. It is required to understand the performance of existing buildings which is the utmost requisite for aging cities. Yangon is one of the largest and ancient cities in Myanmar with significance of about six million population equivalents to 10% total population of the whole country. Therefore, it is striving to identify the quality of earthquake resistant buildings and to acknowledge the need of building inventory in terms of vulnerability assessment. The studied scope covers the evaluation of downtown 5 townships in Yangon city, Myanmar. The buildings are discussed and illustrated by conditions assessment as a quick sidewalk survey. In addition, the level 2 analysis of rapid visual screening (RVS) method classified and prescribed vulnerability assessment with reference to FEMA 154 P. This paper reflects the risk of earthquake impact due to the insufficient building performance. It also enables to determine the prioritization in decision making for strengthening vulnerable building stocks in regard to seismic safety. Keywords: Vulnerability Assessment, Earthquake, RVS, Yangon, Existing Buildings 92 | P a g e

DRSD21_65 Multi-Hazard Impact and Vulnerability Analysis in Building City Infrastructure Resilience Pawel Gromek [email protected] ABSTRACT Cities could be simultaneously affected by multiple hazards. This states a serious challenge for building infrastructure resilience. Especially, when some objects can be dedicated for emergency services and crisis managers and/or constituted critical infrastructure (nationally and/or internationally). As they are characterized by different impact and vulnerability for cascading effect materialization, the two should be considered in safety and security analysis. The objective is to analyze impact and vulnerability of crisis city hazards, crucial city infrastructures and their relations in terms of cascading effect materialization. The study bases on a case of Swinoujscie city in Poland, as it plays a crucial role in state and European critical infrastructure. I used public literature sources (incl. crisis management plans), geospatial data and checklists to identify crisis hazards and crucial infrastructure (referring to critical infrastructure) of the city. Their logical network relations were indicated and analyzed by experts in strategic security management via teamwork formula. This allowed to estimate potential of the hazards and the infrastructures due to cascading effect development in the city and to create foundations for formulation of guidelines for city infrastructure resilience. Terrorist attack, internal fire, cyberthreat and electricity breakdown could cause the most serious multi-consequences. While the energy, energy resources and fuel supply systems turned out the most significant for cascading effect initiation. The results proved that first responders would be the most vulnerable in terms of cascading effect development, decreasing the city resilience during multi-emergency response. Multi-hazard impact and vulnerability analysis map interconnection between the hazards and the infrastructures and indicates kinds of infrastructures at the highest priority in resilience building. The methodological layer refers to methods and tools accessible and cognitively friendly for a wide spectrum of users (especially public administration and services). It can be used in multiple safety and security analysis dedicated for urban areas. Keywords: Multi-Hazard, Vulnerability, Resilience, Network, Critical Infrastructure 93 | P a g e

DRSD21_236 Multi-Hazard Risk Assessment of Educational Institutes of Dehradun, Uttarakhand Shivani Chouhan*, Aishwarya Narang, Mahua Mukherjee [email protected] ABSTRACT The last few decades have been witnessed the impact of multi-hazard frequency in Uttarakhand, India, due to the geographical features of the Himalayas and its neo- tectonic mountain-building process. Dehradun is the capital of Uttarakhand state and comes under seismic zone IV, which is highly prone to earthquakes. In the event of a disaster, educational institutions like schools serve as lifeline buildings. Hence, it is crucial to safeguard these buildings for the communities that may depend on the school as a disaster shelter and aid center. With the same aim, multi-hazard risk assessment surveys have been conducted at 50 schools (with 246 building blocks) in Dehradun. The hazard assessment is divided into two types of surveys: Firstly, building level surveys that include Rapid Visual Screening (RVS), Non-Structural Risk Assessment (NSRA), Fire Safety Audit and Secondly campus-level surveys that include vulnerability analysis for earthquake, flood, industrial hazard, landslide, and wind. This paper will list several gaps and unrecognized practices in the region that increase the schools' multi-hazard risk. The study's outcome can help prioritize the planning of Disaster awareness, retrofitting execution, future construction practices, and decision making to minimize the risk and prepare the school for the upcoming disasters. Keywords: Multi-Hazard, Risk Assessment, Vulnerability Survey, Rapid Visual Screening, School Safety 94 | P a g e

DRSD21_260 Saline Intrusion Vulnerability and Resilience in the Mekong River Delta, Vietnam: A Case Study from Tien Giang Province Hue Le*, Thu Vo, Dzung Nguyen, Anh Tran, Yen Hoang, Tuyet Pham [email protected] ABSTRACT The Mekong River Delta, which is in the south of Vietnam, has the highest agricultural production, not only in Vietnam but also in Southeast Asia. This area is also one of the key economic regions of Vietnam that has high population density and a high demand for water resources for domestic and production purposes. In 2020, the Mekong River Delta had nearly 80,000 households facing difficulties in freshwater shortage, thousands of hectares of rice and vegetation died due to the salinization. This paper examines the vulnerabilities and challenges from drought and saline intrusion that communities face in Tien Giang province, one of the most affected by saline intrusion in the Mekong River Delta. This paper presents the findings of a study of the impacts of drought and saline intrusion on the socio-economic life of local people in Tien Giang province, especially the vulnerable groups in the most affected districts in the province. Qualitative data from focus group discussion and key informant interviews found that the dry season of 2019-2020 was considered to be the most fierce and complicated one since the 1990s. In the past, there were 8 months of fresh water and 4 months of salty water, but now 8 months of salty water and 4 months of fresh water. All of this has adversely affected the environment, local people’s livelihoods, and community cohesion. Unplanned and underdeveloped water infrastructures for supply, sanitation, saline intrusion, and pollution pose severe challenges to the area’s already strained adaptive capacity. Keywords: Drought, Saline Intrusion, Vulnerability, Resilience, Mekong River Delta, Vietnam 95 | P a g e

DRSD21_252 Reframing the Disaster Risk discourse to incorporate Indigenous Knowledge Bosco Bwambale*, Jan Maes, Matthieu Kervyn [email protected] ABSTRACT The (inter)national agenda continues to frame Disaster Risk Reduction (DRR) in hierarchies where top-down actors, i.e., scientists and policymakers, to define interventions for communities-at-risk. To make this process context-specific as well as people-contentedness (especially for low-income economies), incorporating indigenous knowledge is increasingly emphasized. Yet the evidence of this emphasis on ground is lacking. Besides, debates on incorporating indigenous knowledge are yet to be incorporated into the dominant discourse on disaster risk and DRR. Bearing by these gaps in mind, this study aimed to achieve a twofold objective: re-frame the dominant discourse on disaster risk and DRR to incorporate debates on indigenous knowledge. Based on the re-framed discourse, it investigates whether and/or how the debate on incorporating indigenous knowledge is the case in contexts where the international agenda is increasingly endorsed. The empirical investigation is based on the case from Uganda, specific focus on the Rwenzori. Here, floods (compounded by landslides) are increasingly producing intense disasters, DRR is hierarchically governed following the international agenda, and plenty of indigenous knowledge that can be tapped is increasingly reported. The analysis, embedded in the inductive-analytical approach, is contrasted with the historical episodes that have shaped the DRR discourse. The contemporary complex paradigm is noted to consider indigenous knowledge as crucial to concretely grasp the drivers of disaster risk and developing commensurate DRR strategies. In practice, however, top-down actors are observed to have a limited incentive to incorporate indigenous knowledge since they propel the hazard paradigm. This masks off context-specificity and people- contentedness as the hazard paradigm nurtures post-political discourses on DRR, thereby detracting meaningful engagement of indigenous knowledge. Meaningful engagement of indigenous knowledge, in view of the complex paradigm, can rather be achieved following the vulnerability standpoint on DRR. Keywords: Political Ecology, Political Geography, Natural Hazards, Discourse Analysis, Indigenous Studies 96 | P a g e

DRSD21_156 Localizing Climate and Disaster Risk Assessment for Selected Communities in Quezon City and Angat, Bulacan Ma. Lorena P. Hernandez [email protected] ABSTRACT In the pursuit of sustainable development in the Philippines, local government units (LGUs) are required to include the results of a Climate and Disaster Risk Assessment (CDRA) in their Comprehensive Land Use Plan (CLUP). CDRA highlights the risk profile of a specific location by identifying its vulnerabilities, exposed units, and adaptive capacities relative to its climate and natural hazards. It is often conducted on a city or municipal scale. While barangays are included in the process, the adaptive capacities of smaller, poor communities are sometimes underestimated and often overshadowed by their vulnerabilities. Their situation is usually regarded as high risk but is not prioritized for interventions because the information is not consolidated. Localizing CDRA by integrating data gathered through community-based activities will allow communities to articulate their vulnerabilities and capacities to their barangay, city/municipal, and provincial LGUs. The study aims to assess the risks of two communities, the Masagana of Angat Homeowners Association, Inc. (Masagana) in Angat, Bulacan and Kawan 1 of the Basic Ecclesial Community in Barangay Tandang Sora, Quezon City according to a localized CDRA process that utilizes Principal Component Analysis. Secondary data gathered from community-based activities and publicly available resources were utilized for analysis and assessment. The outputs produced are expected to enable communities to formulate an action plan that is science-based and context-specific. This will also enable the LGUs to create a more accurate risk assessment and responsive development plan based on the situation of their communities’/constituents’ respective areas. Finally, the study highlights the need for localizing CDRA to increase the number of communities that have the capacity to create a climate-sensitive and disaster-resilient action plan. Keywords: Climate and Disaster Risk Assessment, Community Based, CDRA, Vulnerability, Climate, Philippines 97 | P a g e

DRSD21_117 Cyclonic Damage Assessment of Rural Houses for the East Coastal Region of India Pradeep K. Goyal [email protected] ABSTRACT Tropical cyclones are one of the costliest natural disasters that occur almost every year in coastal regions of India. The east coast of the Indian region is more vulnerable as compared to the west coast. In recent years, several cyclones have occurred and caused substantial damages to house and loss of lives. Damage assessment of houses in a cyclone-prone region is important in relation to cyclone disaster mitigation. A systematic procedure is outlined for damage assessment of rural houses due to cyclonic wind using a component approach. By combining the damage states and using the damage ratio of the component, a damage probability matrix is determined. The Probability of cyclonic wind speed is integrated with the conditional probability of failure of rural houses and conditional mean damage to obtain the overall damage estimate for a specified region. Three types of analysis are carried out showing three types of fragility curves namely annual damage vs. wind velocity, probability of complete failure of houses vs. wind velocity, and probability of failure of some important components vs. Wind velocity. The effects of types of distributions of wind speed, distribution parameters of components and the wind speed are studied. Keywords: Vulnerability, Hazard, Cyclones, Wind speed, Houses 98 | P a g e

DRSD21_61 A study on behavior of Hyperbolic Cooling Tower considering the effect of Soil Structure Interaction Mahesh Kumar C L*, Shwetha K G, Shanthappa B C, Manjunatha K Email ABSTRACT In this present era, the technology in advanced construction has developed to a very large extent. Some parts of constructions are still in improving stage which includes Cooling tower Construction. Hyperbolic cooling towers are large, thin shell reinforced concrete structures which Contribute to power generation efficiency, reliability and to environmental protection. Cooling towers use evaporation of water to eject heat from processes such as cooling the circulating water used in oil refineries and in power plants. Nowadays in many thermal power plants, we can see the Cooling tower. So, preserving this industrial structure is an effort to save the cooling tower from dangerous earthquakes. The present-day cooling towers are exceptional structures in view their sheer size and complexities. Present paper deals with study of Dynamic response that is modal analysis, seismic analysis of the two different cooling towers varying the H/D ratio and thicknesses with fixity at the base boundary condition and the soil is modeled as elastic soil springs for effect of soil structure interaction using Winkler’s model approach. In this paper hyperbolic cooling towers are modeled using Ansys software, which is a Finite element Software. Results show that soil structure interaction effect significantly modifies the earthquake behavior of Hyperbolic Cooling towers. Keywords: Hyperbolic Cooling Tower, Winkler Model, Dynamic Response, Natural Frequency, Maximum Principal Stress 99 | P a g e

DRSD21_63 An Extensive Study on Damage Assessment of Earthquake Affected Buildings in Nepal Mahesh Kumar C L*, Balendra Sah, Shwetha K G, Prabin Bajracharya [email protected] ABSTRACT Damage Assessment is easy and scientific method to figure out the damage of any structure post-earthquake. This method is unique due to its ability to define the damage level of a building in terms of designated number or symbol. A single number value or grade value can define many aspects of damage on structure. After 2015, 7.8 Richter scale earthquakes in Nepal, the need of grading system for damage due to earthquake was in great need. Earlier we had a system of grading damage on structure in terms of red, green, and yellow cards, Damage scale of 1-10 and 1-5 which are a little confusing to use. Here in this study of Damage Assessment due to earthquake, the damage grades are of 1 to 4 scales which are comparatively easy to use. Usually in the grading system of 1 to 5, grades 2 and 3 were similar, whereas grades 4 and 5 were similar as well. To simplify this thing, grading system of 1 to 4 seems easier to understand and elaborate. Structural Analysis of building has been done using ETABS software to state the damage on building clearly unlike visual method of assessing building damage. In this system Earthquake Damage Grade 1(EDG 1) is a light or minor damage like cracks on nonstructural parts of building, EDG 2 is a little more damage which can be mitigated with simple repair techniques, EDG 3 is buildings that can be retrofitted while EDG 4 is the buildings that need to be demolished and rebuilt. Keywords: Damage Assessment, Earthquake, Damage Assessment, Repair, Damage Scale 100 | P a g e

DRSD21_108 Economic impact assessment of energy resilience measures to address risks in a solar power plant - a case study of 700 kW solar power plant in Chiang Mai Rajabhat University Pichayaluck Patumwongsakorn*, Kampanart Silva, Kampanat Thpmanee, Phumanan Niyomma, Nuwong Chollacoop, Naraphon Paoprasert [email protected] ABSTRACT The usage of renewable energy, especially solar power, has been increasing around the world, and also in Thailand. However, several types of risks remain resulting in decreased availability of the electricity generating system, and consequent reduction in profitability. Our previous study selected the 700 kW Solar Power Plant in Chiang Mai Rajabhat University, Maerim Campus, Thailand, as a case study to perform energy resilience assessment and select energy resilience measures to address aforementioned risks. A wide spectrum of energy resilience measures was identified. The resilience measures need to be prioritized for the decisionmakers to choose those that are worth being implemented. This study proposed a framework to prioritize energy resilience measures based on their economic impacts. The key indices used to analyze the impact were the Net Present Value (NPV) and the payback period. Threats identified in this study consisted of power outage, animal invasion, mowing accident, and wildfire. Energy resilience measures that could address those previously identified threats were 1) establishing a plan for emergency response 2) installing animal protection equipment 3) mowing the grass and shaping the trees around the plant to avoid animal invasion 4) better planning a maintenance and equipment backup 5) making signs to warn the lawnmowers 6) drawing a fire protection line 7) installing fire surveillance equipment 8) installing energy storage system 9) installing the islanding system 10) installing the outage warning system via SMS 11) installing power generation 12) planning a better preventive maintenance or 13) training the technicians for maintenance. Measures numbered 1) to 7) were the ones with positive NPVs and payback periods of less than three years. The others were with negative NPVs. Decisionmakers can use these results as baseline information for the decision making on whether or not to implement the proposed energy resilience measures. Keywords: Energy Resilience, Solar Power Plant, Economic Impact, NPV, Payback Period 101 | P a g e

DRSD21_84 Site-specific ground response analysis and liquefaction assessment of Can Tho city (Vietnam) Van-Quang Nguyen [email protected] ABSTRACT Can Tho is the biggest city in the Mekong River Delta, one of five national central cities in Vietnam. However, there is no study on seismic hazard estimation. For this purpose, one- dimensional nonlinear site response analyses are performed at this city. The measured in-situ profiles and corresponding geotechnical site investigation and laboratory test data are utilized to develop the site model for site-specific ground response analysis. A suite of earthquake records compatible with the Vietnam rock design spectrum (TCVN 9386:2012) is used as input ground motions at the bedrock. From the ground response analysis results, the maximum peak acceleration, the maximum shear strain is discussed. The new design response spectra are then proposed for sites in the study area. Moreover, the liquefaction hazard is quantified using the shear wave velocity-based method. The obtained findings provide a crucial tool for building seismic retrofitting and reducing the risk of small to medium earthquakes in the region. Keywords: Response Spectra, One-Dimensional Nonlinear Site Response Analysis, Peak Ground Acceleration, Shear Strain, Liquefaction Assessment 102 | P a g e

DRSD21_146 Evaluation of empirical SPT blow counts and shear wave velocity correlations using 1D site response analysis for shallow bedrock sites in Islamabad, Pakistan Muhammad Aaqib*, Shamsher Sadiq, Muhammad Bilal Adeel, Van-Quang Nguyen, Ngoc- Long Tran [email protected] ABSTRACT The collapse of Margalla tower building in Islamabad during the 2005 Muzaffarabad Earthquake is a recent example of anomalous damage caused by earthquakes in the region. A well-organized site characterization is necessary for improving the seismic design procedures. To this end, the use of standard penetration test (SPT-N) to obtain shear wave velocity (Vs) profiles in the absence of geophysical field test data is a common practice. In this study, a suite of SPT-N profiles from Islamabad, Pakistan are used and a set of renowned empirical SPT-N and Vs correlations are applied to construct the corresponding shear wave velocity profiles. A suite of one-dimensional site response analysis is then performed on the developed shear wave velocity profiles. Site response outputs are compared with the code- based design spectra of BCP (2007). Based on a residual analysis, the empirical correlations suitable for engineering practice in the context of current seismic design of Pakistan are recommended. Keywords: Seismic Design, Site Response Analysis, Standard Penetration Resistance, Shear Wave Velocity, Building Code of Pakistan 103 | P a g e

DRSD21_142 Livelihood Assessment of Smallholder Rice Farmers in Drought-prone Regions in Bihar, India Vivek Kumar Singh*, Geetanjali Kumari, Amrita Dhiman [email protected] ABSTRACT Bihar is one of the most climate-sensitive states in India due to its geographical setting, hydro- meteorological uncertainties, dense rural population, and high level of poverty. It is an irony of situation that Bihar faces flood and drought simultaneously. The Bihar Disaster Management Plan reveals that 28 districts in the state are prone to floods and 13 districts of the total 38 districts are affected by drought. Smallholder rice farming plays an important role in the economic development of the state and as a prime source of livelihood for about 90% of the smallholder farmers. The climate change and environmental degradation pose a critical challenge to a sustainable livelihood, income, and food security of smallholder rice farmers. The intended objective of this article is to examine various factors affecting smallholder farmers' livelihood in drought-prone areas of Bihar, India, to recommend stakeholders to adapt or change its policy and how to intervene for improving the livelihood of smallholder rice farmers in the region. Qualitative primary data was collected through semi-structured interviews with 27 individual farmers using a checklist in the Aurangabad district of Bihar, India. Two Focused Group Discussions (FGD), first with young farmers and second with aged farmers, and 3 key informants’ interview was organized to validate the findings. Results and discussion of this study indicate that collaboration and coordination among stakeholders have a serious stake in improving the livelihood of smallholder rice farmers. The study found that vulnerability context has a negative impact on smallholder rice farming. The asset portfolio has a positive impact; however, off-farm income should be maximized, and farmer needs on-farm or off-farm work during the lean period. On the basis of findings, the study recommends the stakeholders to develop an Innovation Platform to bring together all stakeholders of smallholder rice farming in the region. Keywords: Smallholder Rice Farmer, Drought, Climate Change, Collaboration and Coordination, Innovation Platform 104 | P a g e

DRSD21_140 Greedy Copula Segmentation applied to Multivariate Non-Stationary Time Series for Optimal Climate Change Adaptation Taemin Heo*, Lance Manuel, Taemin Heo, Lance Manuel [email protected] ABSTRACT An assumption of stationarity in climate variables is common in risk assessments dealing with civil infrastructure systems, even those where the planned service life is long. In a changing climate, however, it is not meaningful in some instances to model climate-related parameters as stationary random processes. In this study, we propose a computationally efficient algorithm called Greedy Copula Segmentation (GCS) and an associated novel climate change adaptation strategy (CCA). GCS partitions a multivariate time series into disjoint segments such that each of the segments is treated as a stationary copula process, but independence is assumed across segments. Our optimal climate change adaptation, GCS-CCA, considers the most recent segment as providing the most informative data for near-future climate pattern prediction. By using only such informative data to build a probabilistic model for the near future, our method predicts climate change discriminately. We provide an algorithm for the formulation of greedy copula segmentation and validate the performance of our methodology on a benchmark problem as well as on a 120-year drought data set from a region around Austin, Texas. Keywords: Drought, Climate Change Adaptation, Copula, Non-Stationary, Infrastructure 105 | P a g e

DRSD21_43 Seismic vulnerability and risk assessment of an existing building in Chennai Kausalya P*, V. Vasugi , M.Helen Santhi [email protected] ABSTRACT There has been an expedited pressure on existing buildings, due to the rapid development of Indian cities. There is a constant need for development of suitable assessment methods to ensure that existent buildings are seismically safe. Various countries have developed different methodologies for evaluating the seismic performance of a building. These methods involve a three-tier assessment, namely rapid visual assessment, preliminary assessment, and detailed assessment. This paper presents the seismic evaluation of an existing five storey residential building in Chennai city, Tamil Nadu. The three assessment phases have been carried out. In the first level of assessment, a data sheet from FEMA 154 is used to evaluate the potential vulnerability of the structure, and this reveals that the building is susceptible to moderate damage. In the second level of assessment, configuration related checks are performed, which reveals that the building has a stiffness irregularity. Hence a final phase of assessment is carried out, where a non-linear static analysis is performed on the structure using SAP2000. As a result, the structure is found to be safe, and has the capacity to meet the seismic demand. Keywords: Reinforced Concrete Building, Rapid Visual Screening, Fema 154, Preliminary Assessment, Detailed Assessment 106 | P a g e

DRSD21_121 Comparison of the Vulnerability Assessment of Step – Back Configuration and Set – Back Configuration Structures on Hill Slopes Yaman Hooda*, Pradeep Kumar Goyal [email protected] ABSTRACT The structures located on the hill slopes are more vulnerable to the seismic activity as comparison to the structures located on the flat regions, because of their both horizontal and vertical irregularities. Due to rapid urbanisation and economic growth, the rate of population in the hilly areas are increasing, thereby increasing the construction of multi – storey structures. This study involves the vulnerability analysis of modelling of G + 5 Storeyed structures, considering both the type of structural configurations on hill slopes: Step – Back Configuration and Set – Back Configuration. The modelling of the structure is done with varying slope angles with respect to the horizontal surface. The hilly areas in India comes under the category of Zone V of Seismic activities as per Ministry of Earth Sciences, Government of India. The analytical tool taken into consideration for the analysis of both the models is Etabs 2019, under the Pushover Analysis. The seismic loads on the structures are being considered as per the guidelines mentioned in Indian Standard IS 1893: 2016. The Pushover Analysis is accompanied with P - ∆ Effect and Gravity Analysis. The comparison is made as per the behavior of the structures with respect to the magnitude of maximum storey displacement, while considering the effects of seismic forces in both the lateral directions. Also, if the structure comes under the category of “Structurally unfit”, then various options of retrofitting technique with bracing is mentioned, having a positive effect on the strengthening of the weak elements of the structures. Keywords: Vulnerability Assessment, Hill Slopes, Step - Back Configuration, Set - Back Configuration, Pushover Analysis 107 | P a g e

DRSD21_240 Time-Frequency Analysis of Strong Ground Motions from the 1999 Chamoli Earthquake Vishwaajith Pemmasani*, Kanuka Mareddy, Jayaprakash Vemuri, KVL Subramaniam [email protected] ABSTRACT On 29th March 1999, the Garhwal-Kumaun region in the western Himalayas was struck by a damaging Mw 6.6 earthquake. The earthquake was recorded at 11 stations in the state of Uttarakhand, India. The earthquake caused immense damage to the built environment in the region which primarily comprises low-rise masonry and reinforced concrete structures. Under severe cyclic motions, induced by earthquakes, these structures undergo damage leading to a reduction in strength and stiffness, thereby causing an increase in their natural period during the duration of an earthquake. The change in the resonant frequency of the structure, during an earthquake, implies that they may be impacted by multiple frequencies present in an earthquake wave. In this paper, the frequency content of 22 horizontal ground motions from the 1999 Chamoli earthquakes are examined using fast Fourier transforms. The time sequencing of frequencies cannot be inferred from fast Fourier transforms and are examined using continuous wavelet transforms. It is observed that the frequency content in strong ground motions is within the range of both the original and altered natural frequencies of low- rise structures. Further, at some stations, these damaging frequencies are observed to arrive at multiple time instants or are sustained in time. These observations correlate well with the observed damage to structures in the region. Keywords: Frequency Content, Fast Fourier Transforms, Continuous Wavelet Transform, Time- Frequency Analysis, Chamoli 108 | P a g e

DRSD21_124 Effect of Transverse Circular and Helical Reinforcements on the Performance of Circular RC Column under High Explosive Loading Rafat Tahzeeb*, Mehtab Alam, S.M.Muddassir [email protected] ABSTRACT Columns are a primary load-carrying member of the structure which transfers gravity loads and external lateral loads of the framed structure to the foundation. Columns under extreme loadings such as blast may become a local hazard, failure of which can lead to the disproportionate or progressive collapse of the building. Not only the subversive reasons but accidental explosions may also cause the failure of the column(s) or building resulting in a huge loss of economy and human lives. Blast resistance of the columns in the building is of serious concern under explosive loadings. Following the validation of experimentally tested square RC column with seismic lateral reinforcement under axial load subjected to an explosive charge of 82kg-TNT at a scaled distance of 1.00m/kg1/3 with 10mm mesh size using ABAQUS/CAE software equipped with concrete damage plasticity model, equivalent circular columns to the experimentally tested ones having circular transverse reinforcement carrying the same axial load with ductile detailing, and helical transverse reinforcement under the same charge are considered. Additional transverse reinforcement of CFRP is also considered over confining regions. Blast performance in terms of maximum displacement, stresses, and damage of the circular columns are computed and compared with those of the square ones. This research highlights the role of equivalent circular columns, and the effect of circular and helical steel and CFRP transverse reinforcements on blast performance under high explosive loading. Keywords: Blast Loading, Circular Columns, Transverse Reinforcement, CFRP, CDP Model 109 | P a g e

DRSD21_242 Time-Frequency Analysis of Strong Ground Motions from the Mw 6.8 1991 Uttarkashi Earthquake Vinuthna Ambatipudi*, Kanuka Mareddy, Jayaprakash Vemuri, KVL Subramaniam [email protected] ABSTRACT The stress build-up along the plate boundary of the Indian and Asian plates is a source of major destructive earthquakes in the state of Uttarakhand. The high seismic hazard in the region has led the Indian Standard Code 1893:2016 to place the entire state of Uttarakhand in seismic zone IV and V, corresponding to seismic intensity levels of severe and very severe, respectively. On 20th October 1991, a strong earthquake having a moment magnitude Mw 6.8, occurred along the Main Central Thrust in the Uttarkashi and Garhwal regions. Field observations indicated that the maximum damage intensity corresponded to a level of IX as per the modified Mercalli Intensity scale. Reconnaissance studies performed in the aftermath of the earthquake indicate that the high lateral forces generated by the horizontal shaking associated with the strong ground motions caused severe destruction of stone masonry and concrete block structures prevalent in the region. Strong ground motions from the 1991 Uttarkashi earthquake are obtained from 13 stations with hypo central distances varying from 22km to 155km. The 26 horizontal waveforms are analyzed and their key characteristics, such as Peak Ground Acceleration (PGA), Peak Ground Velocity (PGV), Arias Intensity (AI), Predominant Period (Tp) and significant duration are tabulated. The frequency content of ground motions is analyzed using fast Fourier transforms and the time-frequency analyses are performed using continuous wavelet transforms. The results indicate that at several sites, the arrival of high-amplitude waves with high frequencies corresponding to the resonant frequency range of low-rise structures corresponds to observed enormous damage to the structures. Keywords: Frequency Content, Fast Fourier Transforms, Continuous Wavelet Transform, Time- Frequency Analysis, Uttarkashi 110 | P a g e

DRSD21_181 Opportunities for implementing multi-hazard impact-based forecast and warning system to achieve Sendai framework for DRR: Bangladesh Mahir Tazwar*, Tahmida Sarkar Muna, Adiba Bintey Kamal, Nawshin Jahan Chaity [email protected] ABSTRACT Multi-hazard impact-based forecast and warning system provides a comprehensive roadmap for better resilience to any community from an impending hazard and enables the individuals, community, stakeholders to respond much better than before. Leading global agreements, call to actions such as the Sendai Framework for Disaster Risk Reduction 2015, the Sustainable Development Goals (SDGs) also emphasize the necessity of multi-hazard impact-based forecast and warning system for effective disaster risk reduction and resilience across the world. This study aims to critically evaluate the significance of transformation from single hazard early warning systems to a holistic approach in observing, modelling, and predicting severe weather and the consequent natural hazards and anticipating their potential impact in developing countries like Bangladesh. At the same time, it also compares the existing early warning system in Bangladesh with a comprehensive multi-hazard impact-based forecast and warning service. This paper is based on narrative literature review due to its ability to address more than one question in a study. The key findings identify some gaps in the existing early warning system in Bangladesh in terms of addressing the gap between forecasts of any hazards and an understanding of their potential impacts, incorporating vulnerability and exposure information in the forecast system, and lastly enabling accurate warning and monitoring systems. Further, this paper reveals that accuracy in hazard identification and monitoring, common situational and risk knowledge, better decision-making capabilities, better contingency planning, and significant reduction in damages and losses are the opportunities of establishing an effective multi-hazard impact-based forecast and warning system over single early warning systems in Bangladesh. Keywords: Multi Hazard, Early Warning System, Disaster Risk Reduction, Sendai Framework For DRR, Impact Based Forecast 111 | P a g e

DRSD21_230 A Framework of Pandemic-Risk Assessment and its Applicability to Reduce the Pandemic’s Adversity Md Shahid Akhter*, Biswanath Dash, Ahanthem Rebika Devi [email protected] ABSTRACT Disaster Risk Assessment (DRA) is the key parameter to understand and manage the adverse consequences of disaster risk. However, there is a significant shortfall of an appropriate and robust “Pandemic-Risk Assessment Framework” which could provide an efficient mechanism to identify pandemic-risk and its comprehensive and effective management plan. Thus, this study will attempt to develop a “Pandemic-Risk Assessment Framework” based on the practical experiences, existing risk assessment frameworks, and available kinds of literature on pandemic risk and its assessment. The primary focus of this framework will be to assess the history of pandemic risk, its exposure and vulnerability to society, and finally the resilience or capacity that reduces the impacts of risk. Initially, the framework will discuss the characteristic feature of pandemic and its historical origin, causes of its explosion across the globe, and various other scientific, and frequency data. Then, in the exposure stage, it will investigate the individuals or groups of people that are highly prone to pandemic risk, and the driving factors of this proneness such as behavioral responses, psychological character and poverty, etc. Subsequently, in the vulnerability section, the framework will examine the susceptibility of exposed healthcare, demographic structure, socio-economic and political conditions. Finally, in the fourth stage, the framework will conclude by addressing the resilience/coping capacities of the system such as integration of governmental institutions to deal with crisis, resources’ availability and its distribution, operational risk communication, and other controlling measures. Keywords: Pandemic, Risk Assessment Framework, Exposure, Vulnerability, Coping-Capacity 112 | P a g e

DRSD21_120 Wavelet Analysis of Strong Ground Motions from the 2015 Nepal Earthquake Mohammed Ayub Ifan*, Shalin Mathew, Jayaprakash Vemuri, KVL Subramaniam [email protected] ABSTRACT Ground motions recorded in earthquakes are time-domain signals. For nonlinear dynamic analyses of structures, analysts use accelerograms, which are the time-acceleration representations of the ground motions. The time-acceleration description hides the information on the frequency content of the ground motions. The Fast Fourier Transform (FFT) is used to obtain the Frequency-Fourier amplitude representation of the accelerogram. However, in this representation, the time information is lost, and it is not possible to discern if the peak amplitudes or energies of the ground motion are reached at single or multiple time instances. Since earthquake ground motions are non-stationary, i.e., their frequency content varies with time, both these representations convey incomplete information. Wavelet analysis provides information on both the time and frequency content of non-stationary signals. In this paper, the continuous wavelet transform (CWT) is utilized to understand the changing time-frequency characteristics of the earthquake ground motions. Recorded near-field ground motions from the massive Mw 7.8 earthquake which struck Nepal on 25th April 2015 are analyzed to understand the influence of their critical characteristics on the observed non- uniform damage to the building stock in the region. It is observed that the response spectra of all recorded ground motions show a very wide acceleration sensitive region, and some ground motions contain significant velocity pulses. Further, while some ground motions exhibit high amplitude waves at the same frequency content over a significant duration of time, other ground motions exhibit high amplitude waves in two to three frequency ranges. It is concluded that these observations correlate well with the observed distribution of damage to reinforced concrete and unreinforced masonry structures in the region. Keywords: Wavelet Analysis, Continuous Wavelet Transforms, Strong Ground Motions, Frequency Content, 2015 Nepal Earthquake 113 | P a g e

DRSD21_54 Development of a Disaster and Climate Risk Atlas in Bangladesh: Methodology for Quantification of Risk Md. Sirajul Islam*, Nurun Nahar, Golam Sarwar [email protected] ABSTRACT Bangladesh is considered as one of the most disaster-prone countries in the world. Almost every year disaster impacts incur a significant amount of economic losses of the country. To improve the disaster resiliency of the country as a whole, Planning Commission of Bangladesh Government, as a timely step, developed a methodology to assess the disaster risk of development projects prior approval through a project supported by ADB. Risk Atlas at district level has been formulated following Intergovernmental Panel on Climate Change (IPCC) guidelines of HEVR model. However, for a particular Hazard (H), what should be the appropriate Exposure (E) and Vulnerability (V) components to quantify the resulting Risk (R), was a question to ponder. After detail review, ten hazards were selected for analysis - six of hydro-meteorological origin as Flood, Drought, Cyclone & Storm surge, Seal level rise and Salinity; two of geo-physical origin as Landslide and earthquake; and two as future climate change scenario (RCP4.5, RCP 8.5) of temperature and precipitation. Five exposure components were people, house, crop, infrastructure, and forest. Eight vulnerability components include socio-economic conditions - poverty, education, gender and livelihood: and lack of infrastructures as medical facilities, cyclone shelter, embankment, and irrigation facilities. A novel approach of assigning appropriate weight for different components of this HEVR analysis was adopted there, adjusting to the country’s real context. In a GIS platform, through overlay approach, the resulting risk maps were prepared. It is expected that the Risk Atlas can be used to carry out a Climate Risk Screening (CSR) and detailed Climate Risk Screening Vulnerability Assessment (CRVA) as well as conduct Disaster Impact Assessment (DIA) of investment projects. Ultimately, it can serve as a guideline or decision-making tool for identifying CCA, and DRR options to safeguard government development projects. Keywords: Bangladesh, Disaster, Climate Change, HEVR, Risk Atlas 114 | P a g e

DRSD21_182 Distance Estimation based on Bounded-Error Estimation, Interval Analysis, and Dempster- Shafer Theory using in Landslide Monitoring Framework Kittikom Sangrit*, Suthum Keerativittayanun, Seksan Laitrakun, Jessada Karnjana [email protected] ABSTRACT One of the essential factors in landslide-prone areas that should be monitored is the land displacement rate, and the extensometer is a widely used measurement device for the task. However, installation of the extensometer requires a comprehensive geographical survey by specialists. As a result, it is time-consuming and requires effort. Therefore, this study aims to utilize an available wireless sensor network (WSN) installed at the landslide-prone area to measure the displacement rate instead. Between two sensor nodes in a WSN, there are pieces of information related to the distance between them, such as the received signal strength indicator (RSSI) and channel state information (CSI). However, RSSI and CSI are subject to noise from the environment, causing errors in the estimated distance. To minimize the errors, we propose a novel framework based on a bounded-error estimation method with interval analysis, where the Dempster-Shafer theory models uncertainties of variables. To evaluate our proposed framework, we conducted experiments in our laboratory. Simulation results showed that the proposed framework could effectively reduce the averaged root-mean-square error (RMSE) to 0.974 m, compared with the averaged RMSEs of 2.273 m and 2.876 m when RSSI and CSI are solely used, respectively. It is also worth mentioning that the wireless sensor nodes used in our experiment are inexpensive; hence, the system is cost-effective for a large-scale early warning system. Keywords: Distance Estimation, Wireless Sensor Network, Bounded-Error Estimation, Dempster-Shafer Theory, Early Warning System 115 | P a g e

DRSD21_135 Clutter Removal Algorithm Based on Grid Density with a Recursive Approach for Rockfall Detection in 3D point clouds from a Terrestrial LiDAR Scanner Phuriphan Prathipasen*, Pitisit Dillon, Jessada Karnjana, Pakinee Aimmanee [email protected] ABSTRACT In the analysis of 3D point clouds obtained from the terrestrial LiDAR scanner for rockfall detection, the general framework consists of three processes: preprocessing, clutter removal, and spatial clustering. A widely-used clutter removal process is based on a nearest-neighbor- related approach, such as the nearest neighbor clutter removal (NNCR) algorithm. However, the NNCR algorithm has a critical problem concerning the computational complexity, i.e., when the number of data points increases, the computational time increases rapidly. Recently, we proposed a new algorithm for clutter removal based on grid density. Even though the previously proposed method was computational-cost efficient, it suffered from two problems: losing some data points around grid edges and losing some points of a rockfall event in which point distributions of its grids are not uniform. In order to solve these problems, this study proposes an improved clutter-removal method by applying the grid-density-based algorithm recursively at multiple scales. Also, with an assumption that the clutter distribution is Gaussian, a new classification criterion for clutter and non-clutter is more effective than the previously proposed one. Experimental results showed that the proposed method could recover points lost by the previous algorithm. In other words, the proposed method was closer to the NNCR algorithm than the previous version in terms of impurity score. Besides, it was approximately 18 times faster than NNCR. Keywords: Rockfall detection, terrestrial LiDAR point cloud, Clutter removal, DBSCAN, Grid Density 116 | P a g e

DRSD21_170 GIS based HVRA for Risk Anticipation and Disaster Risk Reduction Rahim Dobariya*, Nusrat Nasab, Deo Raj Gurung [email protected] ABSTRACT Disasters occur frequently and often place a substantial burden on the community. High vulnerability and insufficient preparedness and response capacities have severe consequences. For over two decades, the Aga Khan Agency for Habitat (AKAH) has been working on disaster risk reduction (DRR) and climate change adaptation programs including a wide range of risk anticipation, prevention, mitigation, preparedness, and response initiatives with local communities, the institutions and governance in Afghanistan, India, Pakistan, Tajikistan, and Syria. AKAH has developed a standardized hazard, vulnerability, and risk assessment (HVRA) approach for systematically risk screening, develop DRR plan, and monitor the impact. The HVRA methodology developed around GIS technology and using index approach determines the extent to which communities are exposed to single or multi- hazards and degree of vulnerability. The risk index is defines based on two main pillars or indicators: hazard exposure and vulnerability. Risk index score helps macro-level planning while exposure and vulnerability index helps micro-level planning within the village. The assessment process carryout in four stages ensures integration of scientific information available with national/international institution and local community knowledge through participatory risk assessment. The process ensures participants from domain experts, community, and stakeholders to incorporate their views on the assessment, maps and response mechanism. The HVRA has been considered as a knowledge hub for AKAH’s DRR work and helped to assess the risk of more than 2500 settlements in the AKAH area of operation. The HVRA result helps to focus on single and multi-hazard-specific interventions. HVRA result communicates often through GIS tools and incorporates into village disaster management plan for short- and long-term planning which helps to bridge risk perception gaps between local communities, governments, and experts. HVRA results are considered as a baseline to monitor impact of DRR interventions. This work was awarded “World Habitat Gold Award 2020” by World Habitat. Keywords: HVRA, DRR, GIS, Index, AKAH 117 | P a g e

DRSD21_37 Predict the critical load of rectangular concrete-filled steel tube columns with ultra-high- strength concrete with software ANSYS Phan Van-Phuc*, Cao Thi-Hao [email protected] ABSTRACT This study presents a method to predict the critical load of short columns filled with super high strength concrete with rectangular cross-section by ANSYS finite element software. In it, the stress-strain relationship of super-high-strength concrete was considered in the form of confined compression, and the Drucker-Prager model available in the nonlinear material library was to conduct a simulation with ANSYS WORKBENCH software. The parameters of the model in turn are considered individually, the obtained results compare it with the experimental results published by Xiong (2017). The final results of this study obtained the effect of the Drucker Prager model parameters on the results of the simulation method with the experiment. Besides, the simulation results with the parameters of the Drucker-Prager model are also presented and the error compared with the experiment is not significant. This study also shows a simpler method than simulation studies for the previous Drucker-Prager model. Keywords: Ultra-High-Performance Concrete, Rectangular Concrete-Filled Steel Tube Columns, Critical Load, Software ANSYS, Drucker-Prager Model 118 | P a g e

DRSD21_122 Methodology and use of impact chains to assess environmental risk in river delta coastal areas socio-ecological systems Emilie Cremin*, Sonia Murshed, Sumana Banerjee, Shah Alam Khan, Mashfiqus Salehin, Anisul Haque, Tuhin Ghosh, Sourav Das, Ly ha Buy, Hieu Hong Hua, Lan Nguyen, Tanh Nguyen, Hue Le, Fabrice Renaud [email protected] ABSTRACT \"River deltas in coastal areas are considered highly exposed to natural hazards such as floods, riverbanks erosion, salinization and storms. The GDRI offers an Index library, that captures both social susceptibility and ecological susceptibility, but also ecological robustness and adaptation capacities to show cumulative impacts, and cascading effects leading to increased risk of loss of sustainable livelihoods in coastal socio-ecological system. To select relevant indicators for the Global Delta Risk Index and adapt the index to each delta, we are developing impact chains to represent the interactions and feedbacks between multiple drivers and factors of change in river delta's coastal socio-ecological systems. The first generic version is based on a literature review, pre-tested consultation with researchers and looks at cross cuts with SDG indicators. This poster presents the methodology used to develop the impact chain designed for the risk assessment of coastal Social-ecological systems. While this framework is well grounded in theories and existing literature, it still needs to be tested empirically. Therefore, delta specific Impact chain will be further developed through a consultation process of deltas experts organized by the research teams of the Living Deltas Hub. The result of this consultation will be used to select the first set of indicators necessary to update the GDRI modular indicator library and to collect the associated data. The data will be processed through normalization, weighting and aggregation. Finally, all the data will be visualized in graphs and spatially, in a GIS. This process helps develop the Global Delta Risk Index specifically for delta’s coastal areas (GDRI-c) to inform policy-makers and further propose solutions to major identified threat in a co-productive manner.\" Keywords: Vulnerability, Risk Assessment, Hazard, Exposure, Resilience, Coping And Adaptation 119 | P a g e

DRSD21_62 Evaluate the durability of RC Bridge under the impact of Climate change in Vietnam Long Tran*, Trong-Ha Nguyen [email protected] ABSTRACT Climate change has been taking on worldwide and it has had negative impacts on almost every field, including construction. This study wants to mention was that the durability of construction deteriorates more quickly. Due to climate change, the air environment has changed greatly in a direction is was harmful to constructions. This has caused a high level of erosion and has a strong impact on the durability of constructions, especially those near the sea. surveyed data on the impacts of the compromised environment on the quality and longevity of RC Bridges in the coastal area. The actual survey data at some reinforced concrete bridges in Vietnam showed that: compressive strength, C25/30, after 30 years of using the durability decreased by 13%, and compressive strength, C30/37, after 25 years of use, the durability decreased by 3.6%. The results of this study have evaluated the current durability and predicted lifespan of RC Bridges affected by environmental erosion caused by climate change. Keywords: Climate Change, RC Bridge, Durability, Construction, Compressive Strength 120 | P a g e

DRSD21_239 Categorization of Differential Impacts of Disasters in the Batangas Province, Philippines Flordeliz Agra [email protected] ABSTRACT The Philippines is one of the most hazard prone countries in the world. It is affected by various types of disasters within a one-year period as experienced by the province of Batangas of last 2020. It was first affected by the Taal Volcano eruption on January 2020, then by Typhoon Rolly last November 2020 amidst the Corona virus pandemic. This study aims to introduce new methods in categorizing the impacts (not affected, very low, low, medium and worst hit areas) of these disasters to Batangas Province by using new methods and formula using population density as the main factor. For example, for Covid 19, results show a totally different one from the traditional methods of categorizing impacts which solely rely on number of persons affected in which Batangas City ranks with the greatest number of cases and thus, considered as worst hit area. However, by using the formula number of cases over population density, Cuenca hails as the worst hit municipality. Regarding Typhoon Rolly and Taal Volcano eruption, same results were obtained using the greatest number of persons affected alone and by using the number of populations affected over population density formula. Nevertheless, for other categories it shows a different result. The findings of the study highlight the need change and start considering using population density as the main determining factor in categorizing differential impacts of disasters for planning and devising a more effective disaster risk reduction and management strategies and approaches Keywords: Disasters, Differential Impacts, Population Density, Category Of Impacts, Batangas Province 121 | P a g e

DRSD21_179 Comparative Analysis of TANK and SIMHYD Rainfall-Runoff models in the Hemavathi watershed, Cauvery Basin, India Masthan Reddy Nagireddy*, Subbarayan Saravanan, Leelambar Singh, Devanantham Abijith Email Id: [email protected] ABSTRACT Runoff models can help with water resource planning and management, drought management, the design of hydraulic structures like dams, bridges, and culverts, and flood forecasting. Several models have been developed in the past decade to simulate the rainfall and runoff relations. Some of the models are simple empirical or complex physical models based on spatially distributed event-based or continuous. This study aims to compare two conceptual daily-based models are TANK and SIMHYD using Rainfall-Runoff Library (RRL) tool. These model parameters are optimised using the genetic algorithm (GA) technique. In RRL, the TANK model consists of four vertical tanks connected in series, with precipitation and evaporation used as inputs in the top tank and evaporation subtracted sequentially from all tanks. SIMHYD is a daily conceptual rainfall-runoff model that estimates daily streamflow from daily rainfall and areal potential evapotranspiration data. In SIMHYD, daily rainfall first fills the interception store, which is emptied each day by evaporation. The excess rainfall is then subjected to an infiltration function that determines the infiltration capacity. The excess rainfall that exceeds the infiltration capacity becomes infiltration excess runoff. The models were calibrated for daily values from 1990 to 2006 and then validated from 2007 to 2015 using the measured discharge at the Sakleshpur gauging site. The effectiveness of model runoff predictions is evaluated using statistical parameters such as Nash–Sutcliffe efficiency and Correlation coefficient values. The NSE values for the TANK model were 0.71 during calibration and 0.54 during validation, 0.66(calibration) and 0.48(validation) for the SIMHYD model. The TANK model's Correlation values were 0.85 during calibration and 0.74 during validation, 0.83(calibration), and 0.73 (validation) for SIMHYD model. From the obtained results, the TANK model performs well in terms of NSE and Correlation compared to SIMHYD model. Keywords: Hamavathi Watershed, TANK Model, SIMHYD, NSE, RRL 122 | P a g e

DRSD21_218 Nat-Bowtie; a New Approach for Natech Risk Assessment Sachin Atmaram Damle*, Shibu Mani, Guru Balamurugan [email protected] ABSTRACT Every technological site has safety systems in place, but natural hazards can interact with the safety systems and pose severe threats to the technological sites. This interaction may result in severe consequences like fire, explosion, the release of hazardous substances, and environmental damage. Such accidents are called a Natech accident. In the present study, the Bowtie method has been modified to assess threats posed by Natech hazards and the new Nat-Bowtie method; a qualitative tool has been proposed. The ready templates of the Nat- Bowtie offer visualization of possible natural threats to the technological systems, which are generally overlooked. Keywords: Technological Systems, Risk, Natural Hazards, Environment, Disaster 123 | P a g e

DRSD21_23 Estimating flood impact using sentinel-1 and ALOS-2/PALSAR-2 imagery: A case study of southern Thailand Gautam Dadhich*, Venkata Sai Krishna, Hiroyuki Miyazaki, Indrajit Pal [email protected] ABSTRACT This article presents a semi-automated methodology for mapping of flooded areas with polarimetric Synthetic Aperture Radar (SAR) data. C-band SAR data is well suited for mapping of open water areas, while L-band enables the extraction of detailed information of flooded farmlands. Here, dual-pol C-band data of Sentinel-1 (S-1) is combined with quad-pol L-band ALOS-2/PALSAR-2 data to enable an accurate mapping of the entire flooded area using kittler and illingworth's minimum error thresholding. The developed procedure combines polarimetric decomposition based unsupervised Wishart classification with automatic thresholding and global auxiliary data. The methodology was tested at the coastal areas of Southern Thailand, where a flooding event occurred in January 2019, Keywords: SAR, Sentinel 1, ALOS 124 | P a g e

DRSD21_276 Livelihood in Normal and Stressed Situations: Pluvial Flood prone Urban Poor Communities in Dhaka, Bangladesh Hasina Akther*, Mokbul Morshed Ahmad [email protected] ABSTRACT This paper investigates the variation and the relationship between normal and urban flood induced stressed livelihood status and the underlying causes. Results revealed that due to socioeconomic conditions of households, one slum was more vulnerable in both situations compared to the other Slum. Both normal and stressed livelihood status of urban poor settlements were significantly different and reflected a positive correlation between the situations. This implies that the livelihood status in normal situation influences on the stressed situation. This study may contribute in risk reduction measures and preparedness program for the urban poor in response to climatic shocks. Keywords: Livelihood, Flood, Slum Dwellers, Dhaka City 125 | P a g e

DRSD21_267 Applying Google Earth Engine for Flood Mapping And Monitoring In The Downstream Provinces Of Mekong River Bui Phan Quoc Nghia*, Indrajit Pal, Nuwong Chollacoop, Anirban Mukhopadhyay [email protected] ABSTRACT Urbanization, irrigation activities and hydropower systems along with the impact of climate change, downstream flood has become more and more complicated in the Mekong Delta, Vietnam. Flood is a hazard, but it is also important for local communities in the Mekong Delta, especially coastal districts because it provides water and nutrients for agriculture and resists to saltwater intrusion. Therefore, monitoring flood in the downstream provinces of the Mekong river is a good way to understand the current situation and can give appropriate solution to reduce damages and get benefits from flood. This study presents the application of Google Earth Engine (GEE) and Sentinel-1 ground range detected synthetic aperture radar (Sentinel-1 GRD SAR) images to visualize and to calculate flood-prone area in the downstream province of the Mekong river basin in Vietnam. In the present study, the observed data of Tan Chau and Chau Doc hydrological station has been used to test and prove the reliability of this application. The output will be integrated with geographic information system (GIS). The analyzed results showed that there is a shift in flood pattern in the downstream provinces of the Mekong Delta. Overall, the level of flood is decreasing; however, the inundation level is increasing in Bac Lieu province. The result of this research also helps to construct a professional support system in monitoring the flood inundation for the Mekong Delta and can give local authorities a big picture about inundation in their area to make decision in flood disaster preparedness, mitigation and adaptation. Keywords: Mekong flood, flood shifting, inundation, urbanization, Google Earth Engine 126 | P a g e

DRSD21_224 Assessment of Flood Hazard in Climatic Extreme Considering River’s Fluvio-Morphic Responses Shampa*, Shampa, Binata Roy, Md. Manjurul Hussain, Md Ashiqur Rahman [email protected] ABSTRACT Climate change is supposed to increase the river discharge and sea level and these borderline changes may shift the river regime i.e., sedimentation pattern or flooding duration during a flood. Most of the hazard assessment studies do not consider such morpho-dynamic responses in assessing the flood risks but these may be critical for the people living on the extremely downstream part of a river. Here, we present a numerical model-based approach to quantify such potential hazard parameters influenced by climate change for the most vulnerable communities living on river bars and islands of the Brahmaputra-Jamuna River. Recent studies showed that with increased global warming, flood inflows of Brahmaputra- Jamuna may increase by 8% to 63% by the end of the 21st century which may change the temporal distribution patterns of precipitation affecting the flood-wave propagation characteristics of the river. This may cause increased incidents of peak synchronization with other rivers resulting in prolonged floods simultaneously triggered by sea-level rise. To assess it, we have set up a hydromorphic model for Brahmaputra-Jamuna River using Delft 3D where climate projections for RCP 8.5 are enforced by a hydrological model of Brahmaputra basin applying SWAT. The simulations covered both RCP 8.5 r1 and r2 conditions and the results reflects the flooding scenarios of 2020s, 2050s and 2080s.Our results showed that the floods in the Brahmaputra-Jamuna River get intense, earlier, frequent and prolonged due to climate change and it is likely to continue till the end of November. The study further reveals that the bars/islands can be affected disproportionally in climate-induced hazards based on their location/position. The bars at the downstream part of the river would be largely affected by the sedimentation in changing climate thus become more vulnerable. The bank-attached bars seem lightly affected than mid-channel bars. This study will assist the policymakers to map the safer places for the bar/island dwellers. Keywords: Bank-Attached Bars; Delft3D; Mid-Channel Bars; Peak Synchronization; RCP 8.5 127 | P a g e

DRSD21_243 An investigation into the socio-psychological manifestations of water insecurity: The post-Amphan scenario in the Sundarban delta Rajarshi Dasgupta*, Pankaj Kumar, Nasif Ahsan, Mrittika Basu, Bijon K. Mitra, Indrajit Pal [email protected] ABSTRACT Advancement in early warning, efficient evacuation and previous experience of cyclones have largely restricted disaster casualties in the Sundarban delta, including in both India and Bangladesh. Post-disaster soil and inland water salinity, together with loss of agriculture and livestock productivity, nonetheless, remain among the impeding issues affecting peoples’ lives and livelihood at large. Although the issues of water salinity are extensively documented in recent scientific literature, understanding the psychosocial stresses owing to the water uncertainties have not been investigated thoroughly. In a preliminary attempt, we made a qualitative inquiry into the varied socio-psychological manifestation of post-cyclone salinization of surface and groundwater resources. Our findings are based on the outcome of 17 Focus Group Discussions (FGDs) and hundreds of individual interviews, primarily of farmers and ex-farmers from either side of the delta. We applied standard coding and a directed content analysis method to screen the large volume of recorded interview data. The finding indicated varied stress and anxiety issues among the respondents, which include loss of self- esteem, indecisiveness, general anxiety, palpitation, irritation and other mental health issues owing to the mismatch in demand and supply of freshwater, particularly for drinking/ household purposes. Although the intensity of the problem is not uniform, cascading societal impacts such as water conflicts, loss of social relations, postponement of marriages and water- related confrontations are common across the study area. We summarize the psychosocial manifestations of post-cyclone salinization, propose, and argue the importance of adopting the integrated water-wellbeing (IWW) concept. We recommend that while it is utterly important to augment and rejuvenate freshwater water sources, the adoption of integrated water-wellbeing can facilitate a broader perspective to secure, manage and reach synergies in water uses, livelihood security, physical and mental health of communities. Keywords: Cascading disasters, mental health, Integrated water-wellbeing (IWW), Post Traumatic Stress Disorders (PTSD) 128 | P a g e

DRSD21_47 Multi-temporal Satellite-Based Flood Hazard Mapping: A case Study from Khartoum North Locality Mohammed T.M. Ahmed*, Mohamedelamin M. M. Mahmoud, Mohammed T.M. Ahmed [email protected] ABSTRACT Floods are one of the most common natural disasters that cause large numbers of deaths and displacements worldwide. In Sudan, the flood season has severely affected the occupants of various areas such as Sharg-Alneel, Khartoum North (Bahri), and others. It caused damages to the infrastructure, destruction of property as well as urban communities. The objective of this paper is to generate a risk and hazard maps of flood areas in the Khartoum North locality using multi-temporal satellite images and spatial analysis tools. An integrated method and GIS analysis tools have been used to determine risk areas based on slope, drainage buffers, and hydrological soil groups. Multi-seasonal Sentinel-1 GRD SAR images from 2018 and 2019 were acquired pre- flood and post-flood and processed to generate extents of flooding in the corresponding rain months. Multi-seasonal Sentinel-2 images during and after the flooding period were used to generate NDWI (Normalized Difference Water Index). The Land cover maps were prepared using Landsat-8 images to identify the major land-cover in the study area. The flood maps from 2018 and 2019, land cover classes in the affected areas, and NDWI annual results with highly flooded areas were also identified. Multi-temporal satellite analysis and integrated spatial analysis (i.e. Elevation analysis, land-cover classification, and change detection analysis) produce significant results for flood risk assessment. Identifying and prioritizing the affected areas based on spatial analysis besides identifying the magnitude of the flood are effectively determined based on flood mapping in past years. This will help in the modeling and prediction of the behavior of future natural flooding events. Keywords: Flood Mapping; Spatial Analysis; GIS; Multi-Temporal; North Khartoum 129 | P a g e

DRSD21_ 280 Assessing Land Use-Land Cover Change and Its Impact on Socio-economic Mobility of Rajarhat New Town Agglomeration, Kolkata, India Rituparna Acharyya*, Niloy Pramanick, Indrajit Pal, Malay Pramanik, Aditya Bharadwaz, Subhajit Ghosh, Anirban Mukhopadhyay [email protected] ABSTRACT Land use land cover (LULC) act as the mirror of the earth's surface, although it serves as a veil of the earth's surface, safeguarding the ground from the corrosive forces operating on it. Rajarhat New Town is located to the north of East Calcutta Wetlands, a ramsar site and a natural sewage treatment plant for the Kolkata city. But the rapid growth of residential, commercial and industrial developments induced LULC change has an enormous effect on the inhabitants and the environment. Therefore, to identify the pathways of development, this study aims to measure land use adjustments and land cover impact on socio-economic mobility of the Rajarhat-Newtown. The satellite images of 1991 to 2021 is utilized to quantify the pattern of LULC changes. For LULC analysis, Object-Oriented (OO) classification approach has been performed integrated with the flexible cloud framework in Google Earth Engine (GEE) patform. The final classification approach is applied by combining the Machine learning algorithms of Support Vector Machine (SVM) and Random Forest (RF). To synthesize the textural data used for the OO classification within the one band, PCA (Principal Components Analysis) has been applied to the main Grey-Level Co-occurrence Matrix (GLCM) indices. From the results, the negative changes have been identified for almost all the features concerning the base year of 1991. Furthermore, a bivariate analysis has been undertaken to monitor the spatial LULC changes between 1991-21 at 10 year interval over the region. Aside from that, special attention is placed on converting agricultural land to built-up areas, supporting the socio-economic transition of the study area's population. Based on changing LULC pattern from 1991 to 2021, a prediction of LULC for 2031 has been executed for the study area. Conclusively, the identification of LULC changes and its pathways have both beneficial and detrimental impact on society, economy, and environmental sustainability of the region. Keywords: LULC pattern; Rajarhat-New Town; Object-oriented classification; Google Earth Engine; Grey- Level co-occurrence matrix; environmental sustainability. 130 | P a g e

DRSD21_ 304 Building City-Region Sustainable and Resilience: Application of Circulation and Ecological Sphere Approach for bridging the urban-rural systems -A case study of Udon Thani City Region, Thailand Wijitbusaba (Ann) Marome*, Pimnara Rodkul, Bijon Kumer Mitra, Rajarshi Dasgupta, Yatsuka Kataoka [email protected] ABSTRACT Fast growing city region like Udon Thani province in Thailand has experienced several natural resource pressures such as drought and flooding.This is also exacerbated by land use changes and settlement expansions. The approach of Circulating and Ecological Sphere or CES will help to building a more sustainable and resilient city region by providing a linkage between urban and rural natural resource consumption and level of resource dependency and integrating social, environmental and economic considerations within a city-region. CES encompasses spatial integration of urban/peri-urban/rural interdependencies to address complex sustainability challenges related to, for example, climate change mitigation and adaptation, ecosystem services, and green development within a city-region. In this research, an analysis of household consumption on water and food resources across the city-region will be explored to unpack the interrelationship of resource dependency. Coupling with the household consumption analysis, a spatial analysis on commuting pattern for social and economic activities and man-made and natural resource dependency of city-region areas will be further illustrated. Moreover, an awareness and willingness of people towards natural resources and their management will be highlighted to enhance opportunities to build a more sustainable and resilient city-region futures. Keywords: Drought, Flooding, CES, Climate Change Mitigation and Adaptation, Ecosystem Services, and Green Development 131 | P a g e

DRSD21_ 303 Risk of Waste Crisis and Waste Management Solutions in Hoi An City toward Circulating and Ecological Sphere Approach Pham Phu Song Toan*, Le Dinh Cuong [email protected] ABSTRACT Hoi An city (HAC) is an ancient town in the centre of Vietnam, which is known widely as a world cultural heritage (recognized by UNESCO in 1999). Usually, HAC welcomes about 5.5 million arrivals per year, in which international tourist accounts for around 55%. Tourism activities in HAC have been booming and become a primary source of local revenue. The rapid development of the tourism industry has brought many benefits to society, such as job opportunities, improvement of urban landscape and infrastructure, and social welfare enhancement. However, the backside of development is the problems of environmental pollution and ecological imbalance. In which the amount of solid waste has increased significantly in recent years beyond the capacity of the municipal solid waste management system is the most apparent evidence. The collection system is overloaded in urban areas, the waste in rural areas has been stocked for many days, the treatment system has been inadequate, and the dumpsite has quickly filled up. Transporting urban waste to rural areas for landfill, which is the temporary solution of the locality, is facing vehement opposition from people in the countryside and has many disadvantages. This study presents the situation of waste management in HAC, identified the problems and recommend suitable waste management solutions for HAC towards promoting the development and regional balance between urban and rural areas. Keywords: HAC, tourism industry, solid waste, environmental pollution, ecological imbalance 132 | P a g e

DRSD21_ 305 Circulating and Ecological Sphere Perspective for Nagpur Region, India Sameer Deshkar*, Vibhas Sukhwani, Rajib Shaw, Bijon Kumer Mitra [email protected] ABSTRACT The concept of Circulating and Ecological Sphere (CES) has recently been introduced by the Government of Japan to advance a low carbon, decentralized and self-reliant society at all scales, ranging from a neighborhood or municipality to country scale. Building on the principles of material recycling (reduce, reuse, and recycle), the CES concept stresses for enhancing resource circulation at regional level. While this concept is increasingly being promoted as a guiding principle to build future environmental policies in Japan and globally, this chapter discusses its applicability on a specific case of Nagpur region in India. In the backdrop of growing urban population and rapid urbanization, the resource demands in the Nagpur region (like food, energy, water, labour, etc.) are reported to be rising at a rapid rate. At the same time, there is also a proportional increasing in waste generation (both solid and liquid waste). Taking account of the transforming resource utilization trends along the urban- rural continuum, this chapter discusses how the notion of CES could be realized in Nagpur region. Laying high emphasis on effective circulation of the regional resources, the authors also discuss the relevance of CES concept in reference to the Government of India’s Atmanirbhar Bharat (self-reliant India) policy initiative. Keywords: CES, material recycling, environmental policies, waste generation, resource utilization 133 | P a g e

DRSD21_ 221 Disaster Risk Assessment of Rohingya refugee camps of Bangladesh through spatial analysis and compare approaches taken by relevant working agencies Abdullah Al Masud*, Abir Ahammad Talukdar [email protected] ABSTRACT Rohingya people have a long untold history of migration from Myanmar. But the last decade has seen a major crisis in Maungdaw District of Rakhine State in Myanmar which causes a huge refugee influx in Cox’s Bazar District of Bangladesh. Government of Bangladesh has ethically decided to give shelter to these huge displaced peoples and later large number of aid agencies have broaden their hands to help them with assistance from international communities. But the refugee camps have been established in some parts of reserve forest areas of hilly region which have been always threatened by multiple hazardous disasters and the new establishment of large number of people has caused more risks in the region. As a displaced people the community of Rohingyas has lost almost all the means of their livelihoods and the resilience capacity to mitigate the disaster risks which at least they had in their homeland. Though multiple organizations are working to uplift their livelihoods still the regular natural and unforeseen disasters are causing huge damage to the lives there in those refugee camps. For this, organizations have tried to assess the hazard risks in their capacity. In this paper the multiple hazard risks will be assessed and presented through the spatial analysis of GIS and Remote Sensing Data. Moreover, different approaches taken by relevant working agencies in this regard will be compared and reviewed. Keywords: Risk Assessment, Rohingya, Refugee Camp, Spatial Analysis, Working Agencies 134 | P a g e

DRSD21_ 77 Modelling Soil Erosion: Samanalawewa Watershed, Sri Lanka EPN Udayakumara*, ADTN Kumarasiri, JMCK Jayawardana [email protected] ABSTRACT At present, soil erosion can be considered as one of the most important environmental and socio-economic concerns facing mankind. This calamity mostly affects the water quality and soil fertility of the watersheds. Thus, the prime objective of this study is to evaluate and map the rate of soil erosion of the Samanalawewa watershed. The Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST), Sediment Delivery Ratio (SDR) model introduced by the Stanford University-USA was employed at the geographic information system (GIS) and remote sensing (RS) environments. Results of the study revealed that the present human-induced soil erosion of the watershed varies. However, in 2020, the rate of soil erosion ranged from 0 to 3555.7 t/ha/yr with an annual average of 139.9 t/ha/yr, which is ~ 28 times greater than the soil loss tolerance (T) in Sri Lanka. The majority of the area has exceeded the T value due to wanton destruction of forests, periodic forest fires, improper agriculture, urbanization, etc. The findings of the study suggest that the extremely eroded areas have to be protected by adopting the proper soil and water conservation (SWC) measures. Further, it can be recommended that two basic institutional mechanisms/policies viz. Payments for Environmental Services (PES) and Compensations for Environmental Services (CES) have to be developed to compensate individuals or communities for undertaking actions that increase the provision of ecosystem services such as soil and water conservation, water purification, flood mitigation, or carbon sequestration. Keywords: InVEST-SDR model, Soil erosion, Soil conservation, Samanalawewa watershed 135 | P a g e

DRSD21_ 297 A Review on Earthquake –Hazard Risk Vulnerability & Capacity Analysis for South –East Asian Countries Neelay Srivastava*, Ranjan Kumar [email protected] ABSTRACT “South-East Asia is a diverse region with most of countries with high population. SEAR member countries are more vulnerable hosting 40% of the world’s poor population, who face multiple challenges including poverty, education, unemployment, gender inequalities, access to safe drinking water and sanitation, migration, urbanization, and globalization. This research is attempted to understand complex mechanism of overall risk to earth-quake hazards in the region, besides figuring out exactly what are the areas that need immediate attention or scope to improve in a direction to bargain the possible loss of life and property to earthquake. Most of earthquake events affect adjoining countries, thus mutual coordination and assistance has to plan out. In Southeast Asia region, Indonesian and Philippine archipelagos ranged under high seismic hazard while Malaysian peninsula falls under moderately low seismic hazard. The methodology and data for the study has been referred from Inform Index Methodology “Index for Risk Management – INFORM”. The final vulnerability score is was aggregation of two components socio economic vulnerability and other vulnerable groups, which have been quantified through various sub indicators. The ranking value of the index is the result of the methodology that defines the mathematical combination of individual indicators. The severity of impact is not similar for each country in the region depending on the hazard risk vulnerability preparedness and coping capacity. The analysis of overall vulnerability of SEA region shows that Myanmar can be affected adversely during disaster, followed by Nepal and then Bangladesh. The least vulnerable nation is Maldives. The study reveals that Myanmar is most vulnerable in terms of human indexes and needs improvement, while DPR Korea and then Bhutan, the same amount of efforts to be made to reduce its socio-economic vulnerability. The coping capacity of DPR Korea, Myanmar, Nepal and Timor Leste is least in the region. The countries like Myanmar, Bangladesh, Bhutan, India and Nepal which are also at higher risk due to lack of coping capacity. Countries that have low risk due to proper infrastructure in place to fight disasters are: Maldives, Sri Lanka and Thailand. Parts of Nepal, India, Myanmar and Indonesia are at highest risk of Earthquake as they fall in active seismic zones. However, DPR Korea, Thailand, Sri Lanka and Maldives have low to moderate risk of earthquake. We have to institutionalize the mechanism and frame policies to adapt structural safety. Besides land use planning should be such that’s includes seismic micro-zonation information. The health system and emergency services should be more planned, resourceful and trained to deal in mass causality at catastrophe scale. Keywords: Seismic, South-East Asia, Disaster, Earthquake, Index, vulnerable, Coping Capacity 136 | P a g e

DRSD21_ 238 Assessing Coastal Vulnerability and Governance in Mahanadi Delta (Odisha), India Subhajit Ghosh*, Amit Ghosh, Indrajit Pal, Tuhin Ghosh [email protected] ABSTRACT The geo-climatic settings of the Odisha coast is prone to natural calamities like cyclone, storm surge, inundation, along with changing sea level, indicates a higher level of coastal vulnerability. Climate-induced natural hazards are frequent on the Odisha coast, which leads to adverse impact on life and property and intensive crop damage. The coastal economy is based on natural resources and different land use systems, and as a consequence, the region is highly susceptible. It is observed that a considerable number of 128 cyclones occurred on the Odisha coast in the last 200 years, of which 72 cyclones made their landfall in the nineteenth century and the rest 52 in the twentieth century. In future, frequent natural hazards and sea level rise (SLR) will further accelerate the probable impact from storm surges and consequent inundation in Mahanadi delta. The futuristic projection (aiming at the year 2030) of the cyclone, storm surge, inundation and SLR has been estimated using different techniques with analysis of satellite images. The probable impact on the coastal community has also been portrayed. The initiatives of the Government of Odisha towards adaptation, mitigation and risk minimization in different sectors have been documented. There are changes in priorities identified within the process of implementation, while analysing the budgetary allocation and expenditure in different sectors. Keywords: Mahanadi Delta; Coastal Vulnerability (futuristic); Impacts; Governance; Prioritization 137 | P a g e

DRSD21_ 232 Modelling of an Idealised Bifurcation Channel with Weir for Flood Risk Reduction Tan Cha Yao*, Ng Kai Jia , Tan Cha Yao, Teo Fang Yenn [email protected] ABSTRACT Weirs are important hydraulic structures for controlling the distribution of water flow at river bifurcation for flood risk reduction. Many research studies have investigated the effects of weir on the bifurcation flow properties. These studies have some limitations and only showed the discharge ratio was varied by the changes of weir height. Thus, there is a need to further explore on how the changes of overall weir geometry and locations of the weir would affect the flow properties. In this study, a 1D HEC-RAS numerical model was simulated with the application of different parameters for weir geometry and various locations of weir to investigate the flow behaviours of a bifurcation channel. An idealised channel was adopted in this study with a main channel of U-shape and bifurcated into a symmetrical of two U-shape channels. Weirs with rectangular, cipolletti (trapezoidal), and v-notch (triangular) cross- sectional shapes were investigated in this study. Velocity and water profiles with Froude number were presented with proper validation procedures. The results from this study have showed that the relationship of outlet discharge ratio to weir height ratio and crest length or crest angle ratio are linear. On the other hand, the relationship of outlet velocity ratio to weir height ratio and crest length or crest angle ratio are quadratic. The location of weirs has no effects on the discharge partitioning and velocity ratio in a bifurcation channel. By understanding the flow behaviours of channel bifurcation with presence of weirs as controlled structure in this study, potentially flood risks could be reduced with the best practices of flood management. These findings may also serve as an important information for hydraulic engineers when building controlled structure to mitigate flood at rivers with bifurcation, especially in deltas. Keywords: River bifurcation, HEC-RAS, 1D Numerical modelling, U-shape channel, Weir 138 | P a g e

DRSD21_ 271 GIS Based Solid Waste Management of Rajshahi City Corporation Farhana Afroz*, Shahida Afrin, Md. Shahid Uz Zaman [email protected] ABSTRACT Waste management is a global environment issue which concerns about a very significant problem in today’s world. There is a considerable amount of disposal waste without proper segregation which has led to both economic and environment sufferings. It is practiced in many cities. There is a tremendous amount of loss in terms of environment degradation, health hazards and economic descend due to direct disposal of waste. It is better to segregate the waste at the initial stages where it is generated, rather than going for a later option which is inconvenient and expensive. There has to be appropriate planning for proper waste management by means of analysis of waste situation of the area. The present study involves solid waste management strategies of Rajshahi city corporation. The quantity of solid waste depends on type of the city. Population, industrialization, commercialization, living standard etc. plays a vital role on the amount of the solid waste. The percentage of different categories of wastes are organic material 70%, garden waste wood 6%, paper 9%, plastic, textile, rubber, leather 9%, metal, glass 3%, others 3%. From 2004 to 2010 waste generation trend is increased 100 tons/day. If it is not managed properly it can affect public health, socio economic condition, climate and weather. This problem can easily be solved by using geographic information system (GIS). The number of waste collection bins is not enough in some areas. And in some areas there are bins more than necessity. So we can solve this problem by reallocating the waste collection bins based on some criteria. In order to collect solid waste vehicles are used is not enough to manage waste due to size and other obstacles. By using Dijkstra’s shortest path algorithm vehicle routing problem is solved to manage solid waste in an efficient way. The study narrates a case study for the implementation of the Circulating Ecological Sphere (CES) concept to better understand the ecosystem linkages at the urban-rural gradient and plan for regional resilience. With the help of spatially explicit ecosystem service models, we quantified the food production potential and water availability from the urban core to an area within the 20 km radius at a spatial resolution of 30m. The total farmland area was used as a proxy indicator of current and future food production potential. We considered the average yield of 2400 kg/ha of rice and 1500kg/ha for other vegetables. Similarly, we calculated the annual run-off for water availability based on rainfall, evapotranspiration, vegetation status and soil categories. Overall, the study illustrates that it is possible to create a self-sufficient city region under the current land use, though uncertainties exist in future land development. Keywords: Solid waste, GIS, Collection bins, shortest path, Spatial Database (SDB). 139 | P a g e