Soil lab report - soil mechanics lab manual PDF

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Experiment # 1 (A):

Water Content Determination ( By Oven Drying Method): (AASHTO T 89-96), (ASTM : D 4318) Objective:  

To determine the moisture content of a soil sample at temperature (110˚C). Moisture content is used in determining the bearing capacity and settlement.

Apparatus:   

Moisture tins Drying Oven Weighing balance

Procedure:      

Take empty , clean moisture tin and mark it with an identifying number or code. Weigh the container as W1. Take wet soil sample (not less than 20 g) & place it in the moisture tin. Weigh the moisture tin + wet soil & record this as W2. Place it in drying oven at constant temperature of 100±5 ºC for 24 hrs. After 24hrs remove the moisture tin from drying oven and record this as W3.

Balance

Drying Oven

1

Calculations: w=

Ww x 100 Ws

Zone Z-4(a)-1.5 feet Z-4(a)-3.0 feet Z-4(a)-4.5 feet Z-4(b)-1.5 feet Z-4(b)-3.0 feet Z-4(b)-4.5 feet

=

W 2−W 3 x 100 W 3−W 1

W1 (grams) 22.25 24.25 23.11 21.97 22.21 23.11

W2 (grams) 59.73 73.23 75.72 75.71 70.32 71.38

W3 (grams) 55.05 68.5 66.82 69.33 61.15 62.07

Moisture Content (%) 14.27 10.67 20.36 13.47 23.55 23.89

Comments:

Reading is increasing & decreasing at different depth which is due to pressure. From the reading we conclude that as the depth increase moisture content also increase.

2

Experiment # 1 (B):

Water Content Determination ( By Speedy Moisture Meter): (ASTM : D-4944) Objective: 

To determine moisture content of a soil sample by speedy moisture meter.

Theory : The speedy moisture meter provides a quick, simple means of determining the moisture content of soil. It is also known as calcium carbide gas moisture tester. The basic principle behind this method is that the free moisture in the soil reacts with calcium carbide reagent to form acetylene gas. This gas exerts a pressure on the internal side of the walls of speedy moisture meter which is replected by a pressure dial. The pressure dial is calibrated in such a way that pressure reading reflects the percentage moisture by wet weight of soil directly. Reaction: Calcium carbide is used to react with water to produce acetylene gas CaC2(s) + 2H2O(l)

Ca(OH)2(s) + C2H2(g)

The pressure of acetylene gas depends upon the amount of water to produce gas thus the amount of gas produced is the approximate amount of moisture content present in the sample. Apparatus:     

Scoop for measuring Calcium Carbide Reagent Speedy Moisture Meter Steel balls Cleaning brush and cloth Calcium Carbide Reagent

Procedure: 3

    

Weigh approximately 6 grams of wet soil sample on the tarred scale. Put in speedy moisture meter jar having steel balls & appropriate amount of CaC2. Shaking the jar up to 5 min with needle start moving. Note the reading from speedy moisture content. Repeat process up to 3 times.

Speedy Moisture Meter Calculation : w=

w sp x 100 1−w sp

--------------- (1)

where, w = moisture content in percentage of dry weight of soil wsp = moisture content as obtained by speedy moisture meter

speedy moisture reading = 15 % after putting in Eq: (1) , we get w = 17.64 % moisture content by speedy moisture meter is 17.64 %.

4

Experiment # 2:

Specific Gravity Determination: (ASTM : D-854) Objective:  

For the determination of mineral properties present in soil. To find void ratio of soil sample.

Apparatus:       

Pico-meter Weight balance Thermometer Hot plate or Bunsen burner Funnel Drying oven Paper towel

Procedure:       

Measure weight of empty Pycnometer. Note it as W1. Put soil sample in Pycnometer and measure it again and note it as W2. Fill the Pycnometer containing the soil sample with water till the mark and note this weight as W3. Empty the Pico-meter and wash the apparatus thoroughly. Again fill the Pico-meter with water only till the mark. Now note this reading as W4. Repeat the procedure 3 times. Record the temperature of soil water mixture.

Calculations: Gs= Zone Z-4(a)-1.5 feet Z-4(a)-3.0 feet Z-4(a)-4.5 feet Z-4(b)-1.5 feet Z-4(b)-3.0 feet Z-4(b)-4.5 feet

( W 2−W 1 ) α [ ( W 4−W 1 ) − ( W 3−W 2 )] W1 (g) 176.17 176.17 176.17 176.17 176.17 176.17

W2 (g) 226.17 226.17 226.17 226.17 226.17 226.17

W3 (g) 692.53 693.65 690.43 688.43 690.32 694.90

W4 (g) 661.87 661.87 661.87 661.87 661.87 661.87

Gs 2.575 2.73 2.32 2.125 2.31 2.93 5

Experiment # 3 (A):

Particle Size Analyses (Mechanical Analysis): (ASTM : D 422) Objective:   

To find the gradation of soil particles. For the characterization of soil particles. Covers the quantitative determination of the distribution of particle size in soils. Particle sizes ˃ 75µm is determined by sieving Particle sizes ˂ 75µm is determined by a sedimentation process

Apparatus:    

A set of Sieves (#4 - #200) Pulverizer Sieve shaker Weight balance

Procedure:        

Take a sample of soil about 500g & Pulverize. Arrange the sieves in descending order in size i.e. #4, #10, #40, #50, #100, #200. Attach pan at the bottom of all the sieves. Shake the sieves for about 5 to 10 minutes. Weight the mass retained on each sieve. Note the mass retained and fill in the table. Form graph and find value of D10, D60 and D30. Using D10, D30, D60, find value of CU and CC. CU =Coefficient of Uniformity =

(D 60) (D 10) 2

CU =Coefficient of Curvature =

(D 30) ( D 10 ) x (D 60)

6

Calculations: Zone – 4(a) – 1.5 feet Sieve #

Sieve Size (mm)

4 10 20 40 50 100 200 Pan

4.75 2 0.85 0.425 0.3 0.15 0.075 0

Total

Mass Retained (Grams) 86.6 157.77 84.79 57.77 29.95 29.87 26.8 26.32

499.87

% Retained 17.32 31.554 16.958 11.554 5.99 5.974 5.36 5.264

C.M.Retained % C.M.Retained (Grams) 86.6 17.32 244.37 48.874 329.16 65.832 386.93 77.386 416.88 83.376 446.75 89.35 473.55 94.71 499.87 99.974

% Passing 82.68 51.126 34.168 22.614 16.624 10.65 5.29 0

99.974

Initial Weight = 500 g Error = 0.13 g

Sieve Size-% Passing Curve 100

% Passing

80 60 40 20 0 1

10

Sieve Size (mm)

D10 = 0.16 D30 = 0.7 D60 = 2.85 CU = 17.81 CC = 1.07 COMMENT: Well Graded 7

Zone – 4(a) – 3.0 feet Sieve #

Mass Retained (Grams) 152.38 208.39 82.16 30.4 8.92 7.3 5.91 4.31

Sieve Size (mm) 4.75 2 0.85 0.425 0.3 0.15 0.075 0

4 10 20 40 50 100 200 Pan

Total

499.77

% Retained 30.476 41.678 16.432 6.08 1.784 1.46 1.182 0.862

C.M.Retained % C.M.Retained (Grams) 152.38 30.476 360.77 72.154 442.93 88.586 473.33 94.666 482.25 96.45 489.55 97.91 495.46 99.092 499.77 99.954

% Passing 69.524 27.846 11.414 5.334 3.55 2.09 0.908 0

99.954

Initial Weight = 500 g Error = 0.23 g

% Passing

Sieve Size-% Passing Curve 80 70 60 50 40 30 20 10 0 1

10

Sieve Size (mm)

D10 = 0.7 D30 = 2.1 D60 = 4.0 CU = 5.71 CC = 1.57 COMMENT: Well Graded

8

Zone – 4(a) – 4.5 feet Sieve #

Mass Retained (Grams) 228.38 122.33 54.44 33.04 15.28 22.3 19.8 4.92

Sieve Size (mm) 4.75 2 0.85 0.425 0.3 0.15 0.075 0

4 10 20 40 50 100 200 Pan

Total

500.49

% Retained 45.676 24.466 10.888 6.608 3.056 4.46 3.96 0.984

C.M.Retained % C.M.Retained (Grams) 228.38 45.676 350.71 70.142 405.15 81.03 438.19 87.638 453.47 90.694 475.77 95.154 495.57 99.114 500.49 100.098

% Passing 54.324 29.858 18.97 12.362 9.306 4.846 0.886 0

100.098

Initial Weight = 500 g Error = 0.49 g

Sieve Size-% Passing Curve 60

% Passing

50 40 30 20 10 0 1

10

Sieve Size (mm)

D10 = 0.32 D30 = 2.0 D60 = 5.75 CU = 17.97 CC = 2.17 COMMENT: Well Graded

9

Zone – 4(b) – 1.5 feet Sieve #

Mass Retained (Grams) 190.58 143.33 71.25 47.65 17.66 14.77 7.2 6.32

Sieve Size (mm) 4.75 2 0.85 0.425 0.3 0.15 0.075 0

4 10 20 40 50 100 200 Pan

Total

498.76

% Retained 38.116 28.666 14.25 9.53 3.532 2.954 1.44 1.264

C.M.Retained % C.M.Retained (Grams) 190.58 38.116 333.91 66.782 405.16 81.032 452.81 90.562 470.47 94.094 485.24 97.048 492.44 98.488 498.76 99.752

% Passing 61.884 33.218 18.968 9.438 5.906 2.952 1.512 0

99.752

Initial Weight = 500 g Error = 1.24 g

Sieve Size-% Passing Curve 70 60

% Passing

50 40 30 20 10 0 1

10

Sieve Size (mm)

D10 = 0.46 D30 = 1.8 D60 = 4.5 CU = 9.78 CC = 1.56 COMMENT: Well Graded 10

Zone – 4(b) – 3.0 feet Sieve #

Mass Retained (Grams) 149.77 188.01 77.22 48.5 15.93 11.11 4.56 3.61

Sieve Size (mm) 4.75 2 0.85 0.425 0.3 0.15 0.075 0

4 10 20 40 50 100 200 Pan

Total

498.71

% Retained 29.954 37.602 15.444 9.7 3.186 2.222 0.912 0.722

C.M.Retained % C.M.Retained (Grams) 149.77 29.954 337.78 67.556 415 83 463.5 92.7 479.43 95.886 490.54 98.108 495.1 99.02 498.71 99.742

% Passing 70.046 32.444 17 7.3 4.114 1.892 0.98 0

99.742

Initial Weight = 500 g Error = 1.29 g

% Passing

Sieve Size-% Passing Curve 80 70 60 50 40 30 20 10 0 1

10

Sieve Size (mm)

D10 = 0.5 D30 = 1.8 D60 = 3.9 CU = 7.8 CC = 1.66 COMMENT: Well Graded 11

Zone – 4(b) – 4.5 feet Sieve #

Mass Retained (Grams) 196.63 177.7 71.98 34.01 9.24 6.53 2.46 1.5

Sieve Size (mm) 4.75 2 0.85 0.425 0.3 0.15 0.075 0

4 10 20 40 50 100 200 Pan

Total

500.05

% Retained 39.326 35.54 14.396 6.802 1.848 1.306 0.492 0.3

C.M.Retained % C.M.Retained (Grams) 196.63 39.326 374.33 74.866 446.31 89.262 480.32 96.064 489.56 97.912 496.09 99.218 498.55 99.71 500.05 100.01

% Passing 60.674 25.134 10.738 3.936 2.088 0.782 0.29 0

100.01

Initial Weight = 500 g Error = 0.05 g

% Passing

Sieve Size-% Passing Curve 70 60 50 40 30 20 10 0 1

10

Sieve Size (mm)

D10 = 0.78 D30 = 1.1 D60 = 4065 CU = 5.96 CC = 0.33 COMMENT: Poorly Graded

12

Experiment # 3 (B):

Particle Size ( Hydrometer Analysis): (D7928-17) Theory: Hydrometer analysis is the procedure generally adopted for determination of the particle size distribution in a soil for the fraction that is finer than #200 sieve size (0.075mm) . In hydrometer analysis, a soil specimen is dispersed in water. In a dispersed state in the water, the soil particles will settle individually. It is assumed that the soil particles are spheres, and the velocity of the particles can be given by Stoke’s law as

ν=

2 γ s− γ D 2 ( ) 9η 2 w

ν = Velocity of fall of sphere, cm/sec γS = Unit weight of soil, g/cc γW = Unit weight of water, g/cc η = Absolute viscosity of the fluid, dyne- sec/sq.cm D = Diameter of sphere, cm Objective: 

To determine the particle size distribution of particles of soil less than 0.075 mm.

Apparatus:      

Hydrometer (152 H) Hydrometer jar Soil dispersion device (Malt Mixer) Dispersing agent (Sodium Hexa-Meta- Phosphate NaPO3) Thermometer Stopwatch

13

“Zone – 4-a”

% Finer

Hydrometer Analysis 45 40 35 30 25 20 15 10 5 0

Hydrometer Analysis

0

0.01

0.02

0.03

0.04

0.05

0.06

Particle Size

14

“Zone – 4-b”

% Finer

Hydrometer Analysis 45 40 35 30 25 20 15 10 5 0 0

0.01

0.02

0.03

0.04

0.05

0.06

Particle Size

15

Experiment # 4:

Determination of Atterberg’s Limits (Liquid Limit & Plastic Limit): (ASTM : D4318) Theory: The liquid limit and plastic limit are two “limits” proposed by A. Atterberg , a Swedish agricultural scientist. 

Liquid Limit: Moisture content below which the soil behaves as a plastic material. At this moisture content, the soil is on the verge of becoming a viscous fluid.

 

Plastic Limit: Moisture content below which soil is non-plastic. Shrinkage Limit: That moisture content below which no further soil volume reduction (or shrinkage) occurs.

Objective:   

To determine the liquid limit. To determine the plastic limit. To determine the liquid limit.

Apparatus:         

Cassagrande’s apparatus Cleaning cloth Water content equipment Containers Weight balance Glass plate Spatula Grooving tool

16

--------------------------------------------------------Zone 4-a-1.5-----------------------------------------------------------LIQUID LIMIT TEST : S. No

No. of Blows

W of Cane W of Cane + soil (g) (g) 1 17 16.27 19.43 2 30 16.44 17.56 PLASTIC LIMIT & SHRINKAGE LIMIT TEST : W of Cane (g) 15.49

W of Cane + Soil (g) 20.18

W of Dried Soil (g) 19.3

W of Dried soil (g) 18.61 17.31

M. C 35.043 28.736

P.L (%) 23.097

L.L (%) 31

S.L (%) 10

--------------------------------------------------------Zone 4-a-3.0-----------------------------------------------------------LIQUID LIMIT TEST : S. No

No. of Blows

W of Cane W of Cane + soil (g) (g) 1 19 16.44 19.78 2 29 16.77 17.56 PLASTIC LIMIT & SHRINKAGE LIMIT TEST : W of Cane (g) 15.5

W of Cane + Soil (g) 21.3

W of Dried Soil (g) 20

W of Dried soil (g) 18.78 17.37

P.L (%) 28.89

M. C 42.74 31.67

L.L (%) 36

S.L (%) 14

17

--------------------------------------------------------Zone 4-a-4.5-----------------------------------------------------------LIQUID LIMIT TEST : S. No

No. of Blows

W of Cane W of Cane + soil (g) (g) 1 15 16.44 19.65 2 26 16.77 17.56 PLASTIC LIMIT & SHRINKAGE LIMIT TEST : W of Cane (g) 15.6

W of Cane + Soil (g) 21.4

W of Dried Soil (g) 20.3

W of Dried soil (g) 18.69 17.35

M. C 42.67 36.21

P.L (%) 23.4

L.L (%) 37

S.L (%) 10.5

--------------------------------------------------------Zone 4-b-1.5-----------------------------------------------------------LIQUID LIMIT TEST : S. No

No. of Blows

W of Cane W of Cane + soil (g) (g) 1 18 16.44 19.72 2 28 16.77 17.56 PLASTIC LIMIT & SHRINKAGE LIMIT TEST : W of Cane (g) 15.6

W of Cane + Soil (g) 21.4

W of Dried Soil (g) 20.1

W of Dried soil (g) 18.73 17.38

P.L (%) 28.89

M. C 43.23 29.51

L.L (%) 34

S.L (%) 13

18

--------------------------------------------------------Zone 4-b-3.0-----------------------------------------------------------LIQUID LIMIT TEST : S. No

No. of Blows

W of Cane W of Cane + soil (g) (g) 1 16 16.46 19.68 2 31 16.82 17.58 PLASTIC LIMIT & SHRINKAGE LIMIT TEST : W of Cane (g) 15.5

W of Cane + Soil (g) 21.3

W of Dried Soil (g) 20.09

W of Dried soil (g) 18.69 17.38

M. C 44.39 35.71

P.L (%) 26.36

L.L (%) 39

S.L (%) 12.5

--------------------------------------------------------Zone 4-b-4.5-----------------------------------------------------------LIQUID LIMIT TEST : S. No

No. of Blows

W of Cane W of Cane + soil (g) (g) 1 16 16.5 19.65 2 29 16.51 17.6 PLASTIC LIMIT & SHRINKAGE LIMIT TEST : W of Cane (g) 15.5

W of Cane + Soil (g) 21.21

W of Dried Soil (g) 20.13

W of Dried soil (g) 18.65 17.35

P.L (%) 23.33

M. C 46.51 29.76

L.L (%) 35

S.L (%) 9.99

19

Experiment # 5 (B):

Compaction Test (Modified AASHTO): (ASTM : D1557) Objective:   

To find the compaction of soil. To find the maximum dry density of soil. To find the optimum moisture content of soil.

Compaction of soil increases its density and produces three important effects; 1. ↑ Shear strength of soil. 2. ↓ Settlement of the soil. 3. ↓ Permeability of the soil. Apparatus:       

Mold & Collar Standard compaction Hammer Moisture tins Weight balance Sieve no 4 Drying oven Trimming Knife

Modified Proctor Test: 20

Vmould = 0.00333 f3 S.No

Water added w (%)

Wmould + Soil (kg)

Wsoil (kg)

6 9 12 15 18

5.36 5.48 5.52 5.44 5.38

1.92 2.04 2.08 2 1.94

1 2 3 4 5

Wsoil (lbs)

lb ) 3 ft γb= Wsoil / Vmould γb (

4.23 4.5 4.58 4.41 4.28

126.95 134.88 137.53 132.24 128.27

lb ) 3 ft γd= γb/ 1+w γd (

119.26 124.07 122.44 115.15 108.45

Moisture Content: Cane + Soil W2

S.No

Cane W1 (g)

(g)

1 2 3 4 5

16.16 17.12 16.11 16.61 31.14

34.15 29.22 43.37 40.99 71.2

M.C

γd

(%)

(pcf)

6.45

119.26

8.715

124.07

12.32

122.44

14.84

115.15

18.28

108.45

Cane + Dry Soil W3 (g)

33.06 28.25 40.38 37.84 65.01

M.C (%)

6.45 8.715 12.32 14.84 18.28

RESULT : MDD = 124.07 pcf OMC = 8.715 %

Experiment # 5 (A): 21

Compaction Test (Standard AASHTO): (ASTM : D4318) Objective:   

To find the compaction of soil. To find the maximum dry density of soil. To find the optimum moisture content of soil.

Compaction of soil increases its density and produces three important effects; 4. ↑ Shear strength of soil. 5. ↓ Settlement of the soil. 6. ↓ Permeability of the soil. Apparatus:       

Mold & Collar Standard compaction Hammer Moisture tins Weight balance Sieve no 4 Drying oven Trimming Knife

Standard Proctor Test: 22

Vmould = 0.00333 f3 S.No

Water added w (%)

Wmould + Soil (kg)

Wsoil (kg)

8 11 14 17 20

5.14 5.26 5.3 5.22 5.16

1.7 1.82 1.86 1.78 1.72

1 2 3 4 5

Wsoil (lbs)

lb ) 3 ft γb= Wsoil / Vmould γb (

3.75 4.01 4.1 3.92 3.79

112.4 120.34 122.98 117.69 113.73

lb ) 3 ft γd= γb/ 1+w γd (

103.76 108.12 107.58 99.773 94.509

Moisture Content: Cane + Soil W2

S.No

Cane W1 (g)

(g)

1 2 3 4 5

16.16 17.12 16.11 16.61 31.14

35.15 30.22 42.37 39.99 70.02