GROUP 1 E-ZINE

JANUARY 2021 GEOTECHNICS Laboratory Testing Procedure of Tests in SEAA 2012 - Civil Engineering Laboratory 1 School of Civil Engineering Faculty of Engineering Universiti Teknologi Malaysia

CONTENTS PAGE 3 PREFACE PAGE 4-6 G1 - SOIL COMPACTION TEST PAGE 7-12 G2 - SOIL CLASSIFICATION PAGE 13-15 G3 - UNCONFINED COMPRESSIVE TEST PAGE 16-18 G4 - ROCK MECHANICS PAGE 19 REFERENCES

PREFACE This e-zine is about the Geotechnic Laboratory Testing Procedure based on the course SEAA 2012 - Civil Engineering Laboratory 1, comprises testings in Soil Mechanic and Rock Mechanic. We would like to thank to our lecturer that lead in the course SEAA 1713 - Soil Mechanics, Dr. Siti Norafida Jusoh. Thanks for giving us the opportunity to work on this E-zine Project as our understanding about the testing procedure was enhanced throughout the journey in preparing this e-zine. EDITORS: FLORENCE TING YI WEN LEONG LEE YING LIEW GUAN XIAN SUJITRAN NAIR A/L THEYWAHAREN NAIR LECTURER: DR. SITI NORAFIDA JUSOH SENIOR LECTURER SCHOOL OF CIVIL ENGINEERING, UTM 3

SOIL C O M P A C T I O N G1 TEST STANDARD PROCTOR TEST INTRODUCTION Compaction is a During construction, process of mechanically compaction is normally pressing the soil particles together to increase the performed by heavy density by expelling air of the soil. This process can be compaction rollers done in lab as shown in this section. 4

PROCEDURE Prepare at least 5 kg of air-dried soil sample that passes through 20 mm sieve. Mix it with water thoroughly. Weigh the mould with base plate attached to the nearest 1 g. Measure the nternal dimensions to 0.1 mm. STANDARD PROCTOR TEST Attach the extension mould to the Contiue to add in the soil mould assembly on a solid base. mixture and apply the blows Place a quantity of the soil mixture until the amount of soil used is into the mould such that when sufficient to fill the mould body, compacted it occupies a little over with the surface not more than one third of the height of the mould body. 6 mm Rammer falls freely to apply 27 above the upper blows uniformly onto the soil edge of the mould sample from a height of 300 mm body. Remove the as controlled by the guide tube. Ensure that the rammer is not extension, strike off the excess obstructed by soil in the guide soil and level off the compacted tube. soil to the top of the mould using the straightedge. Note:- Remember to control the APPARATUS: total volume of soil compacted. If Cylindrical Metal Bold the amount of soil struck off after Hammer removing the extension is too great, Balance the test results may be inaccurate. Straightedge 5

PROCEDURE STANDARD PROCTOR TEST Weigh the soil and mould with base plate to the nearest 1 g (m3). Remove the compacted soil from the mould and place it on the metal tray. Take a representative sample of the soil to determine its water content. Repeat the experiment. Sample for moisture After that we Optimum content may not be weill get four Moisture taken before doing varying water Content compaction. content. Finally discard the remainder of each Dry Densityt compacted sample. The sample must The graph of dry not be re-used Moisture Content density against in a later test. To Improve the moisture content can Experiment: be plotted. The values of water Crush the soil sample into content corresponding to each several pieces to increase surface area to increase volume of compacted soil are absorption of water. determined. Plot the graph of dry density against moisture content. 6

G2 AIM/OBJECTIVE Soil The objective of the test is to group soil Classification particles into different range of sizes, and subsequently, the relative proportions by dry weight, of each size range. (A) DRY SIEVING This method covers the quantitative The data collected and then plotted into determination of the particle size a graph called particle size distribution distribution in a cohesionless soil curve. The patterns of the curve basically down to the fine-sand size. described the grading characteristics of a soil. THEORY A soil consists of assemblage of The position of a curve on the chart discrete particles of various shapes indicates the fineness or coarseness of and sizes. The character of the soil the grains, the higher and the further to may be known by determining the the left the curve lies, the finer the grains, particle distribution on the soil. and vice versa. The steepness, flatness and general shape indicate the distribution of the grain size for a given soil sample. BASIC DEFINITIONS Particle size is usually given in terms of the equivalent particle diameter: GRAVEL: 60mm to 2mm. SAND: 2mm to 0.06mm SILT: 0.06 to 0.002mm CLAY: smaller than 0.002mm FINES: pass a 63 m sieve 7

APPARATUS Test sieves with the following aperture sizes or that equivalent to BS 1377: Part 2 may be used: 10 mm, 6.3 mm, 2 mm, 1.18 mm, 0.6 mm,0.3 mm, 0.15 mm, 0.063 mm and the appropriate receiver tray and lid. PROCEDURE: 1. Weigh a dry sample (oven- or air-dried) to 0.1% of its total mass of about 200g. 2. Fit the largest size test sieve appropriate to the maximum size of material present to the receiver and place the sample on the sieve. 3. Shake the sieve set using a suitable mechanical shaker for a minimum period of 10 minutes. Particles may be hand placed to see if they will fall through but they shall not be pushed through the sieve aperture. Weigh the amount of retained material on each sieve to 0.1% of its total mass. The table above shows the typical calculation of data obtained from sieve test and the corresponding particle size distribution curve. 8

G2 THEORY Soil The moisture content affects the Classification behaviour of soil. As the soil is gradually dried out, at one point it will exhibit (B) ATTERBERG LIMITS very low shear strength. This test consists of determination When shear stress is removed it is of soil moisture content, which noticed that the soil is permanently deformed from plastic to liquid. deformed. Based on the data, the soil may classify to certain classes. Liquid limit (LL) is the moisture content where soil stops acting as a liquid and behaves like a solid. As the soil is dried even more, the soil is more resistant to higher hear stress. After a certain amount of water is removed, the soil experiences no permanent deformation and fractures. The soil acts as a brittle solid. The limit between plastic limit and brittle failure is known as the plastic limit (PL). Plasticity index (PI) is the range of moisture content in which a soil behaves as plastic; the finer the soil, the greater its plasticity index PI = LL PL 9

The liquid and plastic limits provide the most useful way of identifying and classifying the fine-grained cohesive soils. Particle size tests provide quantitative data on the range of sizes of particles and the amount of clay present, but say nothing about the type of clay. Clay particles are too small to be examined visually, but the Atterberg limits enable clay soils to be classified physically, and the probable type of clay minerals to be assessed. Classification is usually accomplished by means of the plasticity chart. The classifications for cohesive soils, as shown in Figure below, include CL, CI and etc , ML, MI etc. Based on the data obtained from plasticity chart, the soil sample can be accordingly classified using Table below. 10

APPARATUS PLASTIC LIMIT Person carrying out the test needs to ensure his/her hands are clean and free of grease. A flat glass plate, smooth and free of scratches 2 spatulas Apparatus for moisture content determination A short length ( roughly 100mm) of 3mm metal rod PROCEDURE: 1. About 20g of soil sample from the liquid limit test is needed for this test. (NOTE: It is easier to set aside a portion of the soil that is thoroughly mixed before proceeding with the LL test. 2. Once the soil it plastic enough, it is well kneaded and then shaped into a ball. Mould and roll the ball using your fingers and palm to allow the sample to slowly dry. 3. When fine cracks begin to appear on the sample surface, divide the ball into two portions, approximately 10g each. Further divide each portion into 4 separate portions but keeping each set of four together. 4. Each portion is the moulded into a 6mm diameter thread using fingers and thumb. Using steady pressure, roll the thread between fingers surface of the glass plate. The pressure would reduce the diameter of teh thread from 6mm to about 3mm. Roll the soil steadily until the thread crumbles when it has been rolled to a diameter of 3mm. The metal rod is used as a reference to gauge the diameter 11

APPARATUS LIQUID LIMIT A flat glass plate and 2 spatulas Penetrometer that complies with BS 2000: Part 4 A stainless steel cone approximately 35mm long, with a smooth and polished surface, angle 30°±1 One or more metal cup not les than 35 mm diameter and 40mm deep with brim parallel to flat base Apparatus from moisture content determination A wash bottle with distilled water 1. Take a 300g sample of soil that passes through the 425μm sieve 2. Place the soil sample on the glass plate and mix well with distilled water using spatulas until it becomes a paste. 3. Push a portion of the mixed soil into a cup with a spatula ensuring not to trap air. Any excess paste is leveled with a straightedge to obtain a smooth surface. 4. With the penetration cone locked in the raised position, lower the supporting assembly so that the tip of the cone barely touches the surface of the soil paste. When it is in the right position, a slight movement of the cup will mark the soil surface. Lower the stem of the dial gauge to contact the cone shaft and record the reading of the gauge to the nearest 0.1mm. 5. Release the cone for roughly 5 seconds. After locking the cone in, lower the stem of the dial gauge to contact to the cone shaft and record the reading of the dial gauge to the nearest 0.1 mm. Record the difference between beginning and the end of drops as the cone penetration. 6. Take a sample of soil about 10g to determine the moisture content 7. Repeat the steps 4 times by adding distilled water. Only specimens with readings between 15mm to 25 mm are taken. 8. Plot a graph of penetration against moisture content. Moisture content at 20mm penetration is the liquid limit (LL). 12

G3 INTRODUCTION In an unconfined compression test, a cylindrical specimen of cohesive soil is subjected to a steadily increasing axial compression until failure occurs. The axial force is the only force applied to the specimen. The test is normally carried out on 38 mm diameter specimens, but can be performed on specimens up to 100 mm diameter. AIM/OBJECTIVE The test provides an immediate approximate value of the compressive strength of the soil, either in an undisturbed or remoulded condition. It is carried out within a short enough time to ensure that no drainage of water is permitted into or out of the specimen. It is suitable only for saturated, non- fissured cohesive soils. FAILURE CRITERIA The maximum value of the compressive force per unit area at which the specimen can sustain is referred to as the unconfined compressive strength of the soil. In soils of high plasticity in which the axial stress does not readily reach a maximum value, an axial strain of 20 % is used as the criterion of failure. 13

TYPES OF TEST There are 2 methods to find the unconfined compressible strength of a soil specimen 1. Definitive method, using load frame specimen of any suitable diameter can be used 2. Make use of auto-graphic apparatus PROCEDURES ( LOAD FRAME METHOD) 1. Determine the mass of the prepared test specimen to the nearest 0.1g. 2. Make at least three measurements of length and of the diameter of the specimen to the nearest 0.1 mm, and determine the average dimensions. 3. Place the specimen in the loading device so that it is centred on the bottom platen. NOTE: Avoid disturbance especially if the specimen is soft, and avoid loss of moisture from the soil. 4. Adjust the loading device carefully so that the upper platen just makes contact with the specimen. NOTE: A small seating force indicated by the force-measuring device confirms when contact is made. The force is included as part of the force applied to the specimen. 5. Adjust the axial deformation gauge to read zero or choose an appropriate initial reading. 6. Record the initial readings of the force and compression gauges. 7. Select rate of axial deformation such that the rate of axial strain does not exceed 2% / min. 8. Apply compression to the specimen at the selected rate and record simultaneous readings of the force-measuring device and the axial deformation gauges at regular intervals of compression, e.g. corresponding to each 0.5% strain. Obtain at least 12 sets of readings in order to define the stress-strain curve. Figure 1 : 9. Continue the test until maximum value of axial stress (calculated Apparatus set up as in 3.3) has been passed, or the axial strain reaches 20 %. for unconfined 10. Remove the load from the specimen and record the final reading compressive test of the forces measuring gauge as a check on the initial reading. 11. Sketch the mode of failure of the specimen. 14

CALCULATION AND PLOTTING 1. Calculate the axial strain, ε , for each set of readings using ∆the equation ε= L/L₀ , where ∆L = change in length of the specimen as indicated by the axial deformation gauge (in mm) L₀ = initial length of the specimen (in mm). 2. Calculate the force, P (in N), applied to the specimen for each set of readings by multiplying the change in reading of the force-measuring device from zero load (in divisions of digits) by relevant load calibration factor (in N/division or N/digit). 3. Calculate the axial compressive stresses, σ1 (in kPa), in the specimen for each set of readings, on the assumption that the specimen deforms as a right cylinder, from the equation σ1= [P(1-ε)/A₀] x 1000 A₀ is the initial cross-sectional area of the specimen (in mm2 ) 4. Plot calculated values of compressive stress as ordinates against corresponding values of strain (expressed in percentage) as abscission, and draw the stress- strain curve through the points 5. From this graph, the unconfined compressive strength, qu (kN/m2 ) is evaluated as either the maximum value of load per unit area or the load per unit area at 20% strain, whichever occurs first. 6. Determine the axial strain of the specimen at failure. 7. Calculate the moisture content, bulk density and dry density of the test specimen. 8. Plot Mohr’s circle and determine the unconfined compressive strength Figure 2: Example of Mohr's Circle 15

G 4 - 1 CORE Procedure: LOGGING 1. Record the length of the core run of core no.1 which will be recorded as C1. 2. Measure and record the length of the core recovered of C1. Strength, weathering effects and the 3. Counted the number of solid core pieces which are longer than 100mm and discontinuities are the important measure length of each of them. characteristics of a rock on 4. Repeat steps 1 to 3 by replace core C1 with C2, C3, C4 and C5 5. Calculate and record CR% and RQD% of each core. determining its engineering properties. 6. Determine the rock mass quality based on RQD% recorded. The Discontinuities are the most 7. Make the description of each core based on their weathering state and special significant of these and so features. particular attention is paid to this aspect. HOW TO CALCULATE CR% AND RQD%? Several samples of rock cores recovered will be collected in this experiment so that their physical feature can be studied and described in the following manners: a) Material characteristics: strength, texture, colour, structure, grain size, rock name. b) General information: additional information and minor constituents, geological information c) Mass characteristics: weathering state, fracture state, discontinuities IMPROVEMENT OF Apparatus: EXPERIMENT: (TO 1. Core Barrel IMPROVE UR EXPERIMENT 2. Measuring tape RESULTS) Facts: Why we usually take account into length of solid core pieces which are longer than 1. To check the colour of the 100 mm into our calculation of RQD value? core, wetting of the core is the best achieved by means of a garden insecticide spray. 2. Use a magnifying glass to check the state of weathering of the core samples. 3. Fractures induced by handling or the drilling process should not be counted(the cores should be fitted together before measuring the length) 4. Avoid parallax error while taking the reading. Figure on left show another bias associated with the assumed threshold length of RQD. Hypothetically, a rock mass which has uniform core pieces length of less than 100mm would yield a RQD of 0%, while a rock mass with a uniform spacing of more than 100mm would yield a RQD of 16 100%.

SCHMIDT REBOUND2-4G PROCEDURE HARNESS TEST 1. Calibrate the Schmidt Hammer In this experiment, Schmid Hammer will be used to with calibration test from 10 to determine the rebound hardness of rock and also its 100 rebound values. uniaxial compressive strength(UCS). 2. Ensure the test surface which must a least 15 cm diameter to be Rebound distance of hammer mass is proportional to smooth, flat and dry. the total energy absorbed by test surface when impact occurs. 3. Use sample cradle o minimum weight of 20 kg to hold the The rebound number which is also called as rebound specimen so that it would have no index corresponds to quality of test sample. vibration and movement during the test. Apparatus: The Schmidt hammer-Type L with impact energy of 4. By holding the instrument perpendicular to the test surface, 0.74Nm. gradually push the body of Sample cradle (steel) of minimum weight of 20 kg. Schmidt Hammer toward the test surface to release the plunger and Advantage of experiment: then impact occurs. Maintain 1. Simple to use pressure on the instrument and 2. low price and easy to get lock the plunger. Disadvantages 5. Record the hammer reading as 1. Unreliable for the detection of flows rebound number. 2. Only the local point and layer of 6. Repeat steps 4 and 5 at masonry to which instrument is different location which must at applied can be evaluate least 25 mm apart with each other. Take at least 10 readings to Improvement/Precautions: ensure accuracy. 1. It is important to record the 7. Take average reading of orientation of the instrument with rebound number which will be respect to horizontal to recorded as rebound index to the nearest 45degree increment for determine quality of concrete. the purpose of determining the correction factors. 17 2. Test should be repeated at least 10 times to ensure accuracy. 3. The point of impact should be at least 20mm away from the edge or sharp discontinuity.

POINT LOAD TEST G4-3 INTRODUCTION Point load test is carried out on core rock specimens or irregular rock fragments to obtain the point load strength index (Is(50)) and unconfined compressive strength. This test does not require costly specimen preparation and is a quick simple test. The failure load P and the distance between platens D are measured to obtain the uncorrected point load strength P/D2. A correction is applied to account for the specimen size and shape, and the unconfined compressive strength is obtained from a correlation equation. Depending on the specimen geometry, three types of tests can be performed: diametral, axial, and irregular lump. APPARATUS PROCEDURE (axial testing) 1. Core specimens with length/diameter ratio of 1⁄3 to 1 are suitable for axial 1. A Point Load Tester 2. Load Measuring System testing. Suitable specimens can be obtained by saw-cutting or chisel-splitting 3. Vernier Caliper 4. Rock Specimens the core sample, or by using suitable pieces produced by carefully planned diametral tests. OBJECTIVE 2. Insert a specimen in the test machine and close the platens to make contact along a line perpendicular to the core end faces . ATo determine the compressive 3. Record the distance, D, between platen contact points . Record the strength of rock specimens from specimen width, W perpendicular to the loading direction, with an accuracy irregular lump test. of 65 %. 4. Steadily increase the load such that failure occurs within 10 to 60 s, and PROCEDURE (diametral testing) record the failure load, P. The test should be rejected if the fracture surface passes through only one loading point . 5. Procedures 2-4 are repeated for each test specimen of the rock type. 1. Core specimens with length/width PROCEDURE (axial testing) ratio greater than one are suitable f 1. Rock blocks or lumps, 30 to 85 mm, and of the shape shown in Fig. 3(c) and or diametral testing. (d)are suitable for the block and the irregular lump tests. The ratio, D/W, 2. Insert a specimen in the test should bebetween 1⁄3 and 1, preferably close to 1. The distance L should be at least 0.5 W. Suitable specimens can be obtained by saw-cutting or chisel- device and close the platens to splitting largersamples or specimens if needed. make contact along a core 2. Insert a specimen in the testing machine and close the platens to make diameter. Ensure that the distance, contact with the smallest dimension of the lump or block, away from edges L, between the contact points and and corners. the nearest freeend is at least 0.5 3. Record the distance D between platen contact points. Record the smallest times the core diameter. specimen width, W, perpendicular to the loading direction. If the sides are 3. Determine and record the not parallel, then calculate W as (W1 + W2)/2 as shown on Fig. 3. This width, distances D and L . W, is used in calculating point load strength index irrespective of the actual 4. Steadily increase the load such mode of failure. that failure occurs within 10 to 60 4. Steadily increase the load such that failure occurs within 10 to 60 s,and s, and record failure load, P. The record the failure load, P. The test should be rejected if the fracture surface test should be rejected if the passes through only one loading point. fracture surface passes through 5. Procedures 2-4 are repeated for each test specimen in the sample. 18 only oneplaten loading point . statement.

REFERENCE 1.(“Rebound Hammer Test Procedure for Concrete Hardness”), Mar 03,2017.Retrieved from https://gharpedia.com/blog/rebound-hammer-test-procedure-for-concrete-hardness/ 2.(“THE BASICS OF LOGGING CORE FOR EXPLORATION” (n.d)).Retrieved from https://canadamines.ca/basics-of-logging-core-samples-for- mineral-exploration/ 3.ASTM International. Standard Test Method for Determination of the Point Load Strength Index of Rock and Application to Rock Strength Classifications. 2007. Retrieved from http://web.mst.edu/ License: ASTM 4.Determination of Plastic Limit of Soil. (2018, August 14).Retrieved from https://theconstructor.org/geotechnical/determination-plastic-limit-soil/2929/ 5.Dr. Nor Zuraiahetty Mohd Yunus, Muhammad Azril Hezmi, Dr Siti Norafida Jusoh. 2020. Soil Mechanics.SKAB1713/SEAA1713-2020/21-01.Malaysia. School of Civil Engineering, University of Technology Malaysia. 6.Dr Siti Norafida binti Jusoh, Dr Muhammad Naqiuddin bin Mohd Warid. MANUAL CIVIL ENGINEERING LABORATORY 1. School of Civil Engineering. University of Technology Malaysia. 7.FPrimeC,July 9, 2019. Estimate Concrete Strength Using Rebound Hammer. Retrieved from https://www.fprimec.com/estimate-concrete-strength-using-rebound-hammer/ 8.Huvaj, N. (2019, June 5). Atterberg Limits. Retrieved from https://www.geoengineer.org/education/laboratory-testing/atterberg-limits 9.Jamal,H. (2017, March 23). Haseeb Jamal. Retrieved from https://www.aboutcivil.org/atterberg-limits.html 10.John Germaine. 1.103 Civil Engineering Materials Laboratory. Spring 2004. Massachusetts Institute of Technology: MIT OpenCourseWare. Retrived from https://ocw.mit.edu. License: Creative Commons BY-NC-SA. 11.John R. Ege, 1987.Core Index, A Numerical Core-logging Procedure for Estimating Rock Quality. Retrieved from https://pubs.usgs.gov/circ/1987/0954/report.pdf 12.LABORATORY TEST # 1 GRAIN SIZE ANALYSIS (ASTM D 422) (SIEVE ANALYSIS). Geotechnical Engineering (CVEN 230), Department of Civil & Arch. Engineering. College of Engineering, Qatar University. Retrieved from https://www.qu.edu.qa/static_file/qu/colleges/engineering/civil/documents/Lab%20Manua ls/Geotechnical_Laboratory_Manual.pdf 13.Mohd Yunus, N., Helmi, M., & Jusoh, S.(2020). Soil Classification. In Soil Mechanics SKAB/SEAA 1713 (pp. 44-49). 14.Suryakanta, February 6, 2016. HOW TO CALCULATE CORE RECOVERY AND RQD OF ROCK? Retrieved from https://civilblog.org/2016/02/06/how-to-calculate-core-recovery-and- rqd-of-rock/ 15.UNCONFINED COMPRESSION TEST. Advanced Geotechnical Laboratory. Department of Construction Engineering. Chaoyang University of Technology, Taiwan; Retrieved from https://www.cyut.edu.tw/~jrlai/CE7334/Unconfined.pdf 16.Unconfined Compression Test - UC Test. Dec 16, 2017. Haseeb Jamal .Retrieved from https://www.aboutcivil.org/unconfined-compression-test 19

“ESSENTIALLY, ALL LIFE DEPENDS UPON THE SOIL… THERE CAN BE NO LIFE WITHOUT SOIL AND NO SOIL WITHOUT LIFE; THEY HAVE EVOLVED TOGETHER.” DR. CHARLES E KELLOGG, SOIL SCIENTIST 20