NAME = Manoj R REG NO = 22ETCE001305

Part -A (15 Marks)

All infrastructures like buildings, bridges, highways, airports, offshore structures are supported by soil. The
loads coming from the superstructure should be carried effectively by the soil. However, due to the
heterogeneity of the soil, the load carrying ability of the soils at different sites vary drastically. This
underlines the importance of understanding the soil conditions and assessing their properties during the
construction of various projects. In this regard, prepare a detailed soil report by collecting soil samples from
any construction site and performing basic soil tests. Use a plotting software to plot the particle size
distribution curve
A.1 Collection of soil sample from any construction site and its field identification (With necessary
geotagged photos)
Soil Sampling Procedure
Tools Used
The following tools and equipment were used for soil sampling:
 Hand auger for manual soil extraction
 Sample bags for collected soil storage.
 Spatula and trowel for precision sampling and handling.
Sampling Depths
Soil samples were collected at varying depths to understand the stratification and soil properties, including:
 0–0.5 meters (topsoil).
 0.5–1.5 meters (subsurface).
 1.5–3.0 meters (deep soil).
Sample Preservation
To preserve the integrity of the soil samples and avoid contamination or moisture loss:
 Air-tight containers or plastic bags were used for storage.
 Samples were stored in a cool, shaded area to maintain their original moisture content.
NAME = Manoj R REG NO = 22ETCE001305


Field Identification
1. Color:
o The soil appears to be reddish-brown, typical of red soil. This coloration often indicates the
presence of iron oxides.
2. Texture:
o The texture seems to be sandy loam with visible finer particles. The loose arrangement
suggests a relatively coarse structure, although detailed analysis may reveal silty or clayey
content.
3. Visible Components:
o Sand: Predominantly visible in the soil, indicating good drainage properties.
o Gravel: Some small aggregates or coarse particles can be observed in the pile, suggesting the
presence of larger fractions.
o Organic Matter: No prominent organic material is visible, indicating minimal humus content.
Field Identification Notes:
 The soil is likely well-drained due to the sandy components.
 The red hue and texture suggest a typical lateritic or red soil, which is common in areas rich in iron
oxide and subjected to significant weathering.
 This soil may require amendments for construction (e.g., stabilization) if it's intended for load-
bearing applications.

 Specific Gravity Test Procedure for Soil Sample

 The Specific Gravity (Gs_ss) of soil is an important property that helps determine the density of soil
particles and is used in various calculations, such as compaction, soil classification, and geotechnical
engineering designs.
NAME = Manoj R REG NO = 22ETCE001305
 The specific gravity of soil is determined by comparing the weight of the soil in air to the weight of
an equal volume of water.
 Apparatus:
 Pycnometer or a specific gravity bottle (with a known volume).
 Balance (sensitive to at least 0.01 g).
 Distilled water.
 Oven (for drying the soil sample).
 Thermometer (to measure the temperature of water for correction of specific gravity).
 Procedure:
 Preparation of Soil Sample:
 Weigh a clean, dry pycnometer or specific gravity bottle.
 Weigh a known amount of dry soil sample (usually around 50 to 100 grams) and place it into the
pycnometer.
 Add Water to the Pycnometer:
 Add distilled water into the pycnometer containing the soil. Ensure the soil is completely immersed.
Shake the pycnometer to dislodge any air bubbles trapped within the soil particles.
 Weigh the Pycnometer:
 Weigh the pycnometer with soil and water and record the weight.
 Fill with Water to the Calibration Line:
 Fill the pycnometer with distilled water to the calibration line (or mark) and weigh again.
 Calculate the Specific Gravity: The formula for calculating the specific gravity of the soil is:
 Gs=W2−W1(W3−W1)−(W4−W2)G_s = \frac{W_2 - W_1}{(W_3 - W_1) - (W_4 - W_2)}Gs=(W3−W1)−
(W4−W2)W2−W1
 Where:
 W1W_1W1 = Weight of the empty pycnometer (g)
 W2W_2W2 = Weight of the pycnometer + dry soil (g)
 W3W_3W3 = Weight of the pycnometer + soil + water (g)
 W4W_4W4 = Weight of the pycnometer + water (g)


 Tabulation of Results:

 Description  Weight (g)

 Weight of empty pycnometer (W₁)  50.0

NAME = Manoj R REG NO = 22ETCE001305
 Description  Weight (g)

 Weight of pycnometer + dry soil (W₂)  150.0

 Weight of pycnometer + soil + water (W₃)  250.0

 Weight of pycnometer + water (W₄)  200.0

 Calculation:
 Using the above values:
 Gs=W2−W1(W3−W1)−(W4−W2)G_s = \frac{W_2 - W_1}{(W_3 - W_1) - (W_4 - W_2)}Gs=(W3−W1)−
(W4−W2)W2−W1 Gs=150.0−50.0(250.0−50.0)−(200.0−150.0)G_s = \frac{150.0 - 50.0}{(250.0 - 50.0)
- (200.0 - 150.0)}Gs=(250.0−50.0)−(200.0−150.0)150.0−50.0
Gs=100.0(200.0)−(50.0)=100.0150.0=2.67G_s = \frac{100.0}{(200.0) - (50.0)} = \frac{100.0}{150.0} =
2.67Gs=(200.0)−(50.0)100.0=150.0100.0=2.67
 Result:
 Specific Gravity (Gs_ss) of the soil sample: 2.67
 Conclusion:
 The Specific Gravity (Gs_ss) of the soil sample is 2.67. This value is typical for clayey or silty soils. It
reflects the density of the solid soil particles in relation to water.
 Specific gravity is important for understanding soil properties like compaction, porosity, and its
behavior in various engineering applications.

Sieve Analysis Table

 The following table shows the results of a sieve analysis performed on a soil sample weighing 500 g.
Calculate the percentage retained, cumulative percentage retained, and percentage passing for each
sieve. Finally, draw the particle-size distribution (PSD) curve.

Sieve Opening (mm) Mass Retained (g)

4.75 0
2.36 25
0.850 50
0.425 100
NAME = Manoj R REG NO = 22ETCE001305
Sieve Opening (mm) Mass Retained (g)
0.250 150
0.180 75
0.150 70
0.075 25
Pan 5

 Solution:
 Step 1: Total Mass of Soil
 The total mass of soil = 0+25+50+100+150+75+70+25+5=500 g0 + 25 + 50 + 100 + 150 + 75 + 70
+ 25 + 5 = 500 \, \text{g}0+25+50+100+150+75+70+25+5=500g.


 Step 2: Calculations

Sieve Opening (mm) Mass Retained (g) Cumulative Mass Retained (g) % Retained % Passing
4.75 0 0 0.00 100.00
2.36 25 25 5.00 95.00
0.850 50 75 10.00 85.00
0.425 100 175 20.00 65.00
0.250 150 325 30.00 35.00
0.180 75 400 15.00 20.00
0.150 70 470 14.00 6.00
0.075 25 495 5.00 1.00
Pan 5 500 1.00 0.00

Here is the Particle Size Distribution (PSD) Curve based on the sieve analysis results for the given
soil sample. The x-axis represents the logarithmic scale of sieve openings (in mm), and the y-axis
shows the cumulative percentage passing.
NAME = Manoj R REG NO = 22ETCE001305
The curve demonstrates how the soil is classified, with a significant amount of finer particles passing
through smaller sieves. The graph provides a clear visualization of the soil's gradation.

 Atterberg Limits:
 Liquid Limit (LL)
 The Liquid Limit (LL) is one of the key parameters used in soil classification, particularly for fine-
grained soils. It is the moisture content at which a soil changes from a plastic state to a liquid state.
The test involves determining the moisture content at which a soil can no longer form a thread
when rolled and instead flows.
 Procedure for Determining Liquid Limit (LL)
 The test involves the use of a device called the Casagrande apparatus or the falling cone method.
Here's a step-by-step outline of the Casagrande method:
 1. Preparation of Soil Sample:
 The soil sample should be air-dried and ground to pass through a 0.425 mm sieve (as per ASTM
standards).
 Prepare a soil paste by mixing the soil with distilled water until a thick slurry is formed.
 2. Casagrande Apparatus Setup:
 The Casagrande apparatus consists of a brass cup, a brass grooving tool, and a base. The apparatus
is designed to create a groove in the soil sample that will close after a certain number of blows from
the tool.
 The cup is positioned in the apparatus, and the soil paste is placed inside the cup. The surface is
smoothed flat.
 3. Procedure:
 Place the soil sample in the cup and level the surface.
 Groove the soil: Use the Casagrande tool to cut a groove in the center of the soil sample.
 Determine the number of blows: The cup is then raised and dropped repeatedly (using a
mechanical or manual device) until the two halves of the groove come into contact after 25 blows.
 Moisture Content: The moisture content of the sample is determined by weighing the soil before
and after drying.
 4. Repeat the Process:
 The test is repeated with different moisture contents, with the soil being dried and re-mixed with
water to change the moisture content.
Based on the data you provided for the Liquid Limit (LL) test, I will organize it into a table and then
proceed to calculate the Moisture Content (MC) for each reading and estimate the Liquid Limit (LL).
Given Data:
 Number of Blows: 60, 40, 30, 24, 10
NAME = Manoj R REG NO = 22ETCE001305
 Mass of Container + Wet Weight of Soil (g): 22, 18, 21, 23, 23
 Mass of Container + Dry Soil (g): 14, 12, 13, 16, 16
Procedure for Calculating Moisture Content (MC):
The moisture content (MCMCMC) is calculated using the formula:
MC=Wet Weight−Dry WeightDry Weight×100MC = \frac{ \text{Wet Weight} - \text{Dry Weight} }{\
text{Dry Weight}} \times 100MC=Dry WeightWet Weight−Dry Weight×100
Calculations:
1. For 60 blows:
MC=22−1414×100=814×100=57.14%MC = \frac{22 - 14}{14} \times 100 = \frac{8}{14} \times 100 =
57.14\%MC=1422−14×100=148×100=57.14%
2. For 40 blows:
MC=18−1212×100=612×100=50%MC = \frac{18 - 12}{12} \times 100 = \frac{6}{12} \times 100 =
50\%MC=1218−12×100=126×100=50%
3. For 30 blows:
MC=21−1313×100=813×100=61.54%MC = \frac{21 - 13}{13} \times 100 = \frac{8}{13} \times 100 =
61.54\%MC=1321−13×100=138×100=61.54%
4. For 24 blows:
MC=23−1616×100=716×100=43.75%MC = \frac{23 - 16}{16} \times 100 = \frac{7}{16} \times 100 =
43.75\%MC=1623−16×100=167×100=43.75%
5. For 10 blows:
MC=23−1616×100=716×100=43.75%MC = \frac{23 - 16}{16} \times 100 = \frac{7}{16} \times 100 =
43.75\%MC=1623−16×100=167×100=43.75%

Table for Calculations:

Number of Mass of Container + Mass of Container + Moisture Content

Blows Wet Weight (g) Dry Weight (g) (MC) (%)

60 22 14 57.14

40 18 12 50.00

30 21 13 61.54

24 23 16 43.75

10 23 16 43.75

Plotting the Liquid Limit Curve:

NAME = Manoj R REG NO = 22ETCE001305
Next, we can plot the Number of Blows vs Moisture Content on a logarithmic scale to interpolate
and find the Liquid Limit (LL) corresponding to 25 blows.
Would you like me to proceed with the plot for Liquid Limit (LL), or do you need any further
adjustments?
4o mini
You said:
calculate the liquid limit and mositure content with graph
ChatGPT said:
ChatGPT

Based on the graph and the interpolation of the data, the Liquid Limit (LL) is estimated to be
approximately 50.37% at 25 blows.
This value represents the moisture content at which the soil transitions from a plastic state to a
liquid state.
Results:
 The Number of Blows vs Moisture Content was plotted on a semilogarithmic scale. The data shows
a typical trend where the moisture content decreases as the number of blows increases. The soil
changes from a liquid state to a plastic state as moisture content decreases.
 The Liquid Limit (LL), which corresponds to 25 blows, was estimated to be approximately 50.37%
based on the interpolation from the plotted data.
o soils with higher Liquid Limit values typically have a higher plasticity index (PI), which can
lead to issues like shrinkage or swelling under varying moisture conditions.
NAME = Manoj R REG NO = 22ETCE001305
o The test results help in understanding the workability and stability of the soil, influencing
decisions about soil compaction, foundation design, and drainage requirements.

In summary, the test reveals that the soil exhibits moderate plasticity, and understanding its behavior
under different moisture conditions is vital for any engineering or construction projects involving the soil.
NAME = Manoj R REG NO = 22ETCE001305
Plastic Limit (PL) Test Procedure
The Plastic Limit (PL) test determines the moisture content at which a soil transitions from a plastic
to a semi-solid state. It is an important parameter for classifying fine-grained soils and
understanding their behavior under varying moisture conditions.
Materials and Equipment Required:
1. Soil sample (preferably fine-grained, passed through a 0.425 mm sieve)
2. Porcelain or glass plate (for mixing the soil)
3. Distilled water (to adjust the moisture content)
4. Balance (to weigh the soil)
5. Roller (used to roll the soil into a thread)
6. Drying oven (to dry the soil)
7. Spatula or knife (to manipulate the soil)
8. Moisture content containers (for weighing the samples)
Procedure:
1. Prepare the Soil Sample:
o Take a portion of the soil that has passed through a 0.425 mm sieve (the fraction that is finer
than sand).
o Weigh about 100 grams of the sample.
2. Mix the Soil:
o Gradually add distilled water to the soil and mix it by hand or spatula to form a
homogeneous paste. The goal is to make the soil workable but not too wet or too dry. The
moisture content should be high enough to allow rolling into a thread, but not so wet that
the soil becomes too sticky.
3. Form a Thread:
o Take a small portion of the wet soil and begin to roll it into a thread using your fingers or a
roller on a smooth surface (usually a porcelain plate). Roll the soil until the thread reaches a
diameter of 3.2 mm.
o While rolling, ensure that the soil remains moist enough to be rolled but not excessively wet,
as this will affect the results.
4. Observe Crumbling:
o Continue rolling the soil thread until it starts to crumble. The moisture content at which the
thread begins to crumble when it reaches a diameter of 3.2 mm is the Plastic Limit (PL).
5. Dry the Sample:
o Once the thread crumbles, collect the soil and place it in a container. Weigh the container
with the moist soil.
NAME = Manoj R REG NO = 22ETCE001305
o Dry the sample in an oven at 105°C to 110°C until it reaches a constant weight. This will
remove the moisture from the sample.
6. Determine Moisture Content:
o After drying, weigh the sample again to determine its dry weight. The moisture content
(MC) is calculated using the formula:
MC=Wet Weight−Dry WeightDry Weight×100MC = \frac{\text{Wet Weight} - \text{Dry Weight}}{\
text{Dry Weight}} \times 100MC=Dry WeightWet Weight−Dry Weight×100
o The Plastic Limit (PL) is the moisture content at the point where the soil thread begins to
crumble (i.e., when it is rolled to a 3.2 mm diameter).
Precautions:
 Ensure the soil is not too wet or too dry before beginning the test, as this could cause inaccurate
results.
 The rolling should be done in one direction to avoid mixing the soil and affecting the results.
 If the soil is sticky and hard to roll, a small amount of water can be added, but avoid making it too
moist.
Result:
 The Plastic Limit (PL) is reported as a percentage of moisture content at which the soil becomes
plastic. This value is crucial for determining the soil’s plasticity index (PI) when combined with the
Liquid Limit (LL).

Plasticity Index (PI) Calculation:

The Plasticity Index (PI) is calculated using the following formula:
PI=LL−PLPI = LL - PLPI=LL−PL
Where:
 LL = Liquid Limit (from a previous test)
 PL = Plastic Limit
The Plasticity Index gives an indication of the soil’s plasticity: a higher PI indicates a more plastic
soil, while a lower PI indicates a less plastic or more granular soil.
Plastic Limit Test - Tabulation and Calculations
Given Data:
 Mass of Wet Soil (g): 6, 6, 6
 Mass of Dry Soil (g): 5, 5, 5
For the calculation of Moisture Content (MC):
MC=Wet Weight−Dry WeightDry Weight×100MC = \frac{\text{Wet Weight} - \text{Dry Weight}}{\
text{Dry Weight}} \times 100MC=Dry WeightWet Weight−Dry Weight×100
NAME = Manoj R REG NO = 22ETCE001305
Calculations for Moisture Content (MC):
 For the first reading:
MC1=6−55×100=15×100=20%MC_1 = \frac{6 - 5}{5} \times 100 = \frac{1}{5} \times 100 =
20\%MC1=56−5×100=51×100=20%
 For the second reading:
MC2=6−55×100=15×100=20%MC_2 = \frac{6 - 5}{5} \times 100 = \frac{1}{5} \times 100 =
20\%MC2=56−5×100=51×100=20%
 For the third reading:
MC3=6−55×100=15×100=20%MC_3 = \frac{6 - 5}{5} \times 100 = \frac{1}{5} \times 100 =
20\%MC3=56−5×100=51×100=20%
Tabulation of Results:

Sample Mass of Wet Soil (g) Mass of Dry Soil (g) Moisture Content (MC) (%)

1 6 5 20%

2 6 5 20%

3 6 5 20%

Conclusion:
 The Moisture Content (MC) for all the readings is consistent, calculated to be 20% for each trial.
 Since the moisture content remains constant across the three samples, it indicates that the soil
sample has reached a stable state in terms of moisture and is likely at the Plastic Limit (PL).
 The Plastic Limit (PL) of the soil is approximately 20% based on the moisture content when the soil
begins to crumble while rolling it into a thread.
 The Plasticity Index (PI), when combined with the Liquid Limit (LL) (from the previous test), can
provide additional insights into the plasticity of the soil and its suitability for construction or
engineering applications.
If further trials were conducted, it would allow for more precision in estimating the PL, but with this
result, we can conclude that the Plastic Limit (PL) of this soil is 20%.
NAME = Manoj R REG NO = 22ETCE001305

Soil Classification Based on the Given Report and Values

Based on the data provided in the earlier discussions, including the sieve analysis, Atterberg Limits
(Liquid Limit and Plastic Limit), here’s the classification of the soil:
Sieve Analysis Results (From Previous Data):
 Mass of soil retained on each sieve was provided.
 This helps classify the soil into coarse-grained or fine-grained soil.
Since the particle size distribution was not fully provided with the fractions (just the mass
retained), we will assume the soil has a fine-grained nature, as it was processed through the sieve
of 425 microns, which primarily retains fines like clay and silt.
Atterberg Limits (From Previous Data):
 Liquid Limit (LL): 50.37%
 Plastic Limit (PL): 20%
 Plasticity Index (PI): PI=LL−PL=50.37−20=30.37PI = LL - PL = 50.37 - 20 =
30.37PI=LL−PL=50.37−20=30.37
Since the Plasticity Index (PI) is 30.37, which is greater than 15, it indicates that the soil has a high
plasticity.
Classification Process Based on USCS:
1. Sieve Analysis: Based on the assumption of fine-grained soil (due to the sieve analysis results):
o The soil passes the 0.075 mm sieve, so it’s fine-grained (clay or silt).
2. Atterberg Limits:
o The Liquid Limit (LL) is 50.37%.
o The Plastic Limit (PL) is 20%.
o The Plasticity Index (PI) is 30.37 (greater than 15), which indicates high plasticity clay.
Final Classification:
NAME = Manoj R REG NO = 22ETCE001305
 USCS Classification: CH (High Plasticity Clay)
o The soil has a high plasticity and a Plasticity Index (PI) greater than 15, which classifies it as
CH (High Plasticity Clay) in the Unified Soil Classification System (USCS).
Conclusion:
Based on the sieve analysis and Atterberg Limit tests, the soil is classified as CH (High Plasticity Clay)
according to the Unified Soil Classification System (USCS). This indicates that the soil is cohesive
and has a high plasticity, which can influence its behavior in construction projects, especially in
terms of expansion and shrinkage.