WEEK 5 ACTIVITY. Lecture (2 hours)

Transcription

1 WEEK 5 ACTIVITY Lecture (2 hours)

2 LEARNING OUTCOMES Week 5 : (3HL) Coverage : Physical Characteristics and Classification of Soils : Density, PSD, ATL, Organic matter, ph value, Compaction test Learning Outcomes : At the end of this lecture/week, the students will be able to : 1. Understand the purpose and objectives of physical characteristics and classification of soils. 2. Determine physical properties of soils based on the analysis of laboratory test data

3 LABORATORY TESTING OUTLINE of PRESENTATION 1.0 Overview 2.0 Scope of laboratory test 3.0 Physical properties tests and their applicability

4 LABORATORY TESTING 1.0 Overview. Based on the soil exploration works carried out two types of samples are normally retrieved from the site. These are disturbed and undisturbed samples. In the SI Planning the engineer/designer must specify the tests that need to be carried out in the laboratory so that relevant and appropriate parameters are obtained to be used in the design of the geotechnical structures.

5 LABORATORY TESTING Standards for testing BS Standards BS1377:1990, BS5930:1999 American Standards ASTM Malaysian Standards MS

6 LABORATORY TESTING 2.0 Scope of Laboratory Tests 2.1 Basic Properties Tests 2.2 Index Properties Tests 2.3 Chemical Properties Tests 2.4 Engineering Properties Tests

7 LABORATORY TESTING 2.1 Basic Properties Tests Include for colour, smell, natural moisture content, G s, Porosity, Void Ratio, Reactivity, etc For soil identification, description, classification and correlation

8 LABORATORY TESTING 2.2 Index Properties Tests Include Atterberg Limits (LL, PL, PI), Shrinkage Limit (SL), Particle Size Distribution (PSD), Organic Content. For soil description, classification and correlation with engineering properties

9 LABORATORY TESTING 2.2 Index Properties Tests Cone Penetration & Casagrande Apparatus for Liquid Limit Test

10 LABORATORY TESTING 2.2 Index Properties Tests Shrinkage Limit Apparatus

11 LABORATORY TESTING 2.2 Index Properties Tests Particle size distribution apparatus

12 LABORATORY TESTING 2.3 Chemical Properties Tests Include Total Dissolved Salts, Sulphate & Chloride Contents, ph value, etc For corrosion and durability assessment of foundation

13 LABORATORY TESTING 2.3 Chemical Properties Tests

14 LABORATORY TESTING 2.4 Engineering Properties Tests Include shear strength, stiffness, compressibility/swelling, compaction/cbr, permeability For analysis and design Can be obtained from insitu testing & laboratory test on undisturbed samples should be compared with correlated values from Index Properties

15 LABORATORY TESTING 2.4 Engineering Properties Tests Triaxial Apparatus for Strength Test

16 LABORATORY TESTING 2.4 Engineering Properties Tests Vane Shear Apparatus Shear Box Apparatus for Strength Test

17 LABORATORY TESTING 2.4 Engineering Properties Tests Consolidation Apparatus to determine compressibility

18 LABORATORY TESTING 2.4 Engineering Properties Tests Automatic Compaction Apparatus CBR Apparatus

19 LABORATORY TESTING 3.0 Physical Properties Tests and their Applicability 3.1 Density Tests 3.2 PSD Tests 3.3 ATL Tests 3.4 Organic Matter 3.5 ph value 3.6 Compaction test

20 SOIL CLASSIFICATION Sieving Apparatus Lid & Pan Particle size distribution apparatus Set of Sieves Sieve Shaker

21 SOIL CLASSIFICATION Sieving Apparatus Particle size distribution accessories Riffle box

22 SOIL CLASSIFICATION Procedures of Sieving Can you differentiate the process between these two types of sieving Dry sieving. Wet sieving BS Test Sieve

23 SOIL CLASSIFICATION Tabulation of Test Data TABLE OF CALCULATION for a typical three stage sieving

24 SOIL CLASSIFICATION Plotting of Graph Geotechnicques I (KJC412) /Soil Mechanics (ECG413) ARM - July 2006 PSD Graph

25 SOIL CLASSIFICATION Analysis of Test Results 100 Percentage Finer Grading Curve 10 0 d 10 d 30 d 60 Particle Size (mm)

26 SOIL CLASSIFICATION Analysis of Test Results Grading Characteristics Based on the plot, the following characteristics are determined in order to classify the soil :- Effective size = D 10 Uniformity Coefficient, Coefficient of Gradation, C u C g D60 D10 2 D30 D x D (C u < 3 is uniformly graded whereas C u > 3 is well graded) (C g ranging between 0.5 to 2.0 to confirm as well graded soil) Percentage Composition

27 SOIL CLASSIFICATION Analysis of Test Results Determination of the grading characteristics of the sample

28 SOIL CLASSIFICATION Fine Grain Analysis Grading of Fine Soil Hydrometer Test (Sedimentation Test) Hydrometer test bulb Hydrometer bath

29 SOIL CLASSIFICATION Fine Grain Analysis Hydrometer Test (Sedimentation Test) Hydrometer test is based on the principles of sedimentation of soil grained in water. This is based on Stoke s law which expressed that: s D where v is the velocity γ s is the unit weight of soil particles, γ w is the unit weight of water, η is the viscosity of water, and D is the diameter of soil particles. w Hydrometer test bulb

30 Cobbles Percentage Passing, (%) Examples of Grading Curves PARTICLE SIZE DISTRIBUTION Job No. Project BH/Pit no. Date Site Client Sample no. Tested by Beta Copy Test method Soil Descrip. Depth (m) Checked by PS4 100 British Standard Sieves, (mm) GRADING CHARACTERISTICS % Gravel F D B % Sand % Silt % Clay D 90 (mm) C A D 85 (mm) D 60 (mm) D 50 (mm) 40 E D 30 (mm) D 15 (mm) 30 D 10 (mm) 20 C u C g 10 Soil Classification particle diameter, (mm) fine medium coarse fine medium coarse fine medium coarse CLAY SILT SAND GRAVEL BBB2000 Remarks :

31 SOIL CLASSIFICATION Determination of Consistency Limits Determination of Consistency Limit tests Liquid Limit test Cone Penetration Method Casagrande method Plastic Limit Test Shrinkage Limit Test

32 SOIL CLASSIFICATION Determination of Consistency Limits Cone Penetration & Casagrande Apparatus for Liquid Limit Test

33 SOIL CLASSIFICATION Determination of Liquid Limit Analysis of Test Data Penetration (mm) 20 mm penetration Liquid Limit Water Content (%) Sample of Cone Penetration Method

34 SOIL CLASSIFICATION Determination of Liquid Limit Determination of Liquid Limit using Cone Penetration Apparatus Tabulation and plot

35 SOIL CLASSIFICATION Determination of Liquid Limit Water Content (%) Liquid Limit Sample of Casagrande s Method Number of Blows, N 25 no. of blow Figure shows the preparation of sample in the brass cup and the sample before and after the test.

36 SOIL CLASSIFICATION Determination of Liquid Limit Determination of Liquid Limit using Casagrande Apparatus Tabulation and plot

37 SOIL CLASSIFICATION Determination of Plastic Limit Figure shows how plastic limit is obtained (1) apparatus for plastic limit, (2) preparation of specimen, (3) the soil is rolled into a thread of 3 mm and (4) crumbling of the soil at 3 mm

38 SOIL CLASSIFICATION Determination of Linear Shrinkage Linear Shrinkage Test

39 COMPACTION OF SOIL Laboratory compaction apparatus LABORATORY DETERMINATION OF THE COMPACTION CHARACTERISTICS OF SOILS

40 COMPACTION OF SOIL Laboratory compaction apparatus LABORATORY COMPACTION COMPACTION MOULD AND RAMMER

41 COMPACTION OF SOIL Laboratory compaction apparatus Automatic Compaction Apparatus CBR Apparatus

42 COMPACTION OF SOIL Analysis of test data A) To determine the compaction characteristics of the soil. o o Maximum Dry Density Optimum Moisture content B) Plotting the air voids line Normally 0%, 5% and 10% C) Plotting zone of variation applicable in the field, i.e. Change in moisture contents and air voids content

43 COMPACTION OF SOIL Analysis of test data RELEVANT FORMULAE FOR DATA ANALYSIS Water content, w Bulk density, Dry density, d b Mass of water Mass of solid Mass of wet soil Total volume Mass of dry soil Total volume M M M V T w s M V T s Also d b ( 1 w) or d Gsw (1 wg s (1 ) A v )

44 COMPACTION OF SOIL Analysis of test data

45 COMPACTION OF SOIL Analysis of test data Field variations

46 LABORATORY TESTING