-Determination of water content of soil by oven drying method -Determination of dry density of soil by sand replacement method -Grain Analysis of Soil -Determination of liquid limit and plastic limit of soil -Liquid limit determination by cone penetrometer -California Bearing Ratio (CBR) value test - Direct shear test -Standard penetration test

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MCT-6209
Foundation Engineering Lab
Experiment File
Prepared By: - ANKAJ KUMAR
Roll No: - 202304
Semester- II
M.E (C.T.M) Regular
Submitted to: - Prof. Dr.V.K Southwal

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Index
Sl.no Pg. no Name of Experiment
1 3 Determination of water content of soil by oven drying method
2 6 Determination of dry density of soil by sand replacement method
3 10 Grain Analysis of Soil
4 13 Determination of liquid limit and plastic limit of soil
5 17 Liquid limit determination by cone penetrometer
6 19 California Bearing Ratio (CBR) value test
7 20 Direct shear test
8 28 Standard penetration test

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Experiment 1st
Determination of water content of soil by oven drying method
The oven dry method is widely used laboratory method determine the water content or
moisture content of given soil sample. It gives very accurate results.
Apparatus Required for Oven Dry Method
To determine water content by oven dry method following equipment is required.
 Hot Air Oven
 Non-corrodible air tight containers ( 3 no’s)
 Digital Weight Machine (accuracy of 0.04% of mass of sample)
 Desiccator
 Tongs
Minimum Soil Sample Quantity
The soil sample collected from the field should be of required quantity to find the water
content. The quantity of soil required is depends upon the maximum particle size and
gradation of soil sample. Below table shows the soil quantity required for test based on the
sieve analysis.
Table 2: Minimum soil sample quantity

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Test Procedure of Oven Dry Method
The test procedure of Oven Dry method to find the moisture content of soil consists
following steps.
 In first step, clean and dry the containers and weigh them and note down the mass of
each container (M1). Also note down the number of each container along with its
weight.
 Collect the soil sample from field. Remove the top layer of soil and collect the wet
soil from bottom layers.
 Fill the containers with required quantity of soil sample and weigh the each container
and note down its mass (M2).
 Place the containers in hot air oven, arrange temperature to 110o
± 5o
C and allow
them to dry for 24 hours.
 After 24 hours turn off the oven and take out the containers using tongs.
 Cool down the containers in desiccator for one hour.
 After that weigh containers and note down the mass (m3) of each container.
Observations and Calculations of Oven Dry Method
The data collected during the test is noted in below data sheet. From this data the water
content of given soil sample is calculated by the below shown formula
Where M1= Mass of empty container with lid, M2= Mass of the container with wet soil
and lid, M3= Mass of the container with dry soil and lid.

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Table 2: Observations and Calculations of Oven Dry Method
Sl. No. Observations and Calculations
Determination no
1 2 3
1 Container No.
2 Mass of empty container (M1)
3 Mass of container + soil (M2)
4 Mass of container + dry soil (M3)
Calculation
5 Mass of water Mw= M2 – M3
6 Mass of solids, Ms= M3 – M1
7 Water content= (5)/(6)x100
Result of Oven Dry Method
Water content of the given soil sample = ______%.

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Experiment 2nd
Determination of dry density of soil by sand replacement method
The sand replacement test method is used to determine in situ dry density of soil. The
procedures, materials, equipment, and specifications of this test is based on the Indian
Standard (IS 2720 part 28). This test is of significant importance and it has been widely used
in various construction project sites.
The field density of natural soil is required for the estimation of soil bearing capacity for the
purpose of evaluation of pressures on underlying strata for computation of settlement, and
stability analysis of natural slope.
The sand replacement test method is also used to determine the in-place density of compacted
soil in order to compare it with the designated compaction degree, hence it specifies how
much the compaction of the soil is close to the designated compaction degree.
Apparatus
1. Sand – pouring cylinder
2. Calibrating container, 100mm diameter and 150mm height
3. Soil cutting and excavating tools, such as scrapper tool, bent spoon
4. Plane surface: Glass or Perspex Plate or Other Plane Surface, 450mm square, 9mm
thick or larger
5. Metal container to collect excavated soil
6. Metal tray, 300mm square and 40mm deep with a hole of 100mm in diameter at the
center
7. Weighing balance accurate to 1 gram
8. Moisture content cans
9. Oven
10. Desiccator
Materials
Clean, uniform sand passing 1mm IS sieve and retained on 600micron IS sieve in sufficient
quantity. It is required to be free from organic substances. The sand should have been dried in
an oven and kept in suitable storage for a period of time to allow its water content to reach
equilibrium with atmospheric humidity.

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Calibrations
1. Measure the internal dimensions of the calibrating container and then calculate its
volume.
2. Fill the sand-pouring cylinder with sand, within about 10mm of its top. Determine the
weight of the filled cylinder (M1).
3. Place the sand-pouring cylinder vertically on the calibrating container. Open the
shutter to allow the sand run out from the cylinder. When there is no further
movement of the sand in the cylinder, close the shutter.
4. Lift the pouring cylinder from the calibrating container and weigh it to the nearest
gram (M2).
5. Place the sand pouring cylinder on the glass plate. Open the shutter and allow the sand
to run out of the cylinder until no further movement of the sand is noticed (sand fills
the cone of the cylinder), and then close the shutter and remove the sand pouring
cylinder carefully.
6. Take the sand on the glass plate and determine its weight (M3)
7. Repeat step 3 to step 6 two more times and record mean weight (mean M2 and M3)
8. Determine the dry density of sand, as shown in Table 1.
Table 1 Calibration for Dry Density of Sand
S. No. Observations and Calculations
Determination No.
1 2 3
1 Volume of calibrating cone VC
2 Mass of pouring cylinder (M1), filled with sand
3 Mass of pouring cylinder after pouring sand
into the calibrating container and cone (M2)

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4 Mass of sand in the cone (M3)
Calculation
5 Mass of sand in the calibrating container,
MC=(1) – (2) – (3)
6 Dry density of sand, ps=MC/VC
Procedure
1. Expose an area of about 450mm square on the surface of the soil mass. Trim the
surface down to a level surface using a scrapper tool.
2. Place the metal tray on the leveled surface.
3. Excavate the soil though the central hole of the tray, using the hole in the tray as a
pattern. The depth of the excavated hole should be about 150mm.
4. Collect all the excavated soil in a metal container, and determine the mass of the soil
(M).
5. Remove the metal tray from the excavated hole.
6. Fill the sand pouring cylinder within 10mm of its top. Determine its mass (M1).
7. Place the cylinder directly over the excavated hole. Allow the sand to run out the
cylinder by opening the shutter. Close the shutter when the hole is completely filled
and no further movement of sand is observed.
8. Remove the cylinder from the filled hole. Determine the mass of the cylinder (M4).
9. Take a representative sample of the excavated soil. Determine its water content.
10. Determine the dry density of soil as shown in Table 2.

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Table 2 Observations and Calculations for Dry Density Test of Soil
SI. No. Observations and Calculations
Determination No.
1 2 3
Observation
1 Mass of excavated soil (M)
2 Mass of pouring cylinder (M1), filled with sand
3 Mass of pouring cylinder after pouring into the
hole and cone (M4)
Calculations
4 Mass of sand in the hole, MS=M1 – M4- M3
5 Volume of sand in the hole V=Ms/Ps
6 Bulk density =M/V
7 Water content
8 Dry density using formula
Result
The dry density of the soil can be calculated using the following formula:
Dry density=Bulk density/ (1+water content) Equation 1

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Experiment 3rd
Grain Analysis of Soil

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Experiment 4th
Determination of liquid limit and plastic limit of soil
Liquid Limit

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Plastic Limit

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Experiment 5th
Determination of liquid limit by cone penetrometer
OBJECTIVE
For determination of the liquid limit of soil using cone penetrometer.
REFERENCE STANDARD
IS : 2720(Part 5)-1985- Methods of test for soils : Determination of liquid and plastic limit.
EQUIPMENT & APPARATUS
 Oven
 Balance (0.01g accuracy)
 Sieve [425 micron]
 Cone penetrometer
PREPARATION SAMPLE
After receiving the soil sample it is dried in air or in oven (maintained at a temperature of
600
C). If clods are there in soil sample then it is broken with the help of wooden mallet.
PROCEDURE
1. About 150 gm. of air dried soil from thoroughly mixed portion of material passing 425
micron IS sieve is obtained.
2. Distilled water is mixed to the soil thus obtained in a mixing disc to form a uniform
paste.
3. Then the wet soil paste is transferred to the cylindrical cup of cone penetrometer
apparatus, ensuring that no air is trapped in this process.
4. Finally the wet soil is leveled up to the top of the cup and placed on the base of the cone
penetrometer apparatus.
5. The penetrometer is so adjusted that the cone point just touches the surface of the soil
paste in the cup and the initial ready is to be taken.
6. The vertical clamp is then released allowing the cone to penetrate into soil paste under
its own weight for 5 seconds. After 5 seconds the penetration of the cone is noted to the
nearest millimeter.
7. The test is repeated at least to have four sets of values of penetration in the range of 14 to
28 mm.
8. The exact moisture content of each trial is determined
CALCULATION
 A graph representing water content on Y – axis and the cone penetration on X – axis is
prepared. A best fitting straight line is then drawn.
 The moisture content corresponding to cone penetration of 20 mm. is taken as the liquid
limit of the soil.

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REPORT
The liquid limit is to be reported to the nearest first decimal place.
SAFETY & PRECAUTIONS
 Soil used for liquid limit determination should not be oven dried prior to testing.
 After mixing the water to the soil sample , sufficient time should be given to permeate
the water throughout out the soil mass
 Wet soil taken in the container for moisture content determination should not be left
open in the air, the container with soil sample should either be placed in desiccators or
immediately be weighed.
Sample graph

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Experiment 6th
California Bearing Ratio (CBR) value test
The California Bearing Ratio (CBR) test is a measure of resistance of a material to
penetration of standard plunger under controlled density and moisture conditions. It was
developed by the California Division of Highways as a method of classifying and evaluating
soil- subgrade and base course materials for flexible pavements. CBR test may be conducted
in remoulded or undisturbed sample. Test consists of causing a cylindrical plunger of 50mm
diameter to penetrate a pavement component material at 1.25mm/minute. The loads for
2.5mm and 5mm are recorded. This load is expressed as a percentage of standard load value
at a respective deformation level to obtain CBR value.
Objective: - The aim of this test is the determination of California Bearing Ratio value of the
subgrade soil.
Apparatus required: - Loading machine-any compression machine can operate at constant
rate of 1.25mm per minute can be used. Cylindrical moulds- moulds of 150mm diameter and
175mm height provided with a collar of about 50mm length and detachable perforated base.
Compaction rammer, surcharge weight-annular weights each of 2.5kg and 147mm diameter.
IS sieve 20mm, Coarse filter paper, balance etc.
Procedure:-
Sieve the sample through 20mm IS sieve. Take 5 kg of the sample of soil specimen. Add
water to the soil in the quantity such that optimum moisture content or field moisture content
is reached. Then soil and water are mixed thoroughly. Spacer disc is placed over the base
plate at the bottom of mould and a coarse filter paper is placed over the spacer disc. The
prepared soil water mix is divided into five. The mould is cleaned and oil is applied. Then fill
one fifth of the mould with the prepared soil. That layer is compacted by giving 56 evenly
distributed blows using a hammer of weight 4.89kg. The top layer of the compacted soil is
scratched. Again second layer is filled and process is repeated. After 3rd
layer, collar is also
attached to the mould and process is continued. After fifth layer collar is removed and excess
soil is struck off. Remove base plate and invert the mould. Then it is clamped to baseplate.
Surcharge weights of 2.5kg is placed on top surface of soil. Mould containing specimen is
placed in position on the testing machine. The penetration plunger is brought in contact with
the soil and a load of 4kg (seating load) is applied so that contact between soil and plunger is
established. Then dial readings are adjusted to zero. Load is applied such that penetration rate
is 1.25mm per minute. Load at penetration of 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 7.5, 10 and 12.5mm
are noted.
Standard Load Values for CBR Test :-
Penetration(mm) Standard Load(kg) Unit Standard Load(kg/cm2
)
2.5 1370 70
5 2055 105
7.5 2630 134
10.0 3180 162
12.5 3600 183

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Observations during CBR Test: -
Weight of soil taken = Weight of surcharge = Area of plunger, A = Proving Ring Calibration
Factor =
Sl No. Penetration(mm)
Proving dial
reading
Load on
plunger(kg)
Corrected
load
Unit Load
Result of California Bearing Ratio Test
1. California Bearing Ratio at 2.5mm penetration =
2. California Bearing Ratio at 5.0mm penetration =
3. California Bearing Ratio of subgrade soil =

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Experiment 7th
Direct Shear test
Objective
To determine the shearing strength of the soil using the direct shear apparatus.
NEED AND SCOPE
In many engineering problems such as design of foundation, retaining walls, slab bridges,
pipes, sheet piling, the value of the angle of internal friction and cohesion of the soil involved
are required for the design. Direct shear test is used to predict these parameters quickly. The
laboratory report cover the laboratory procedures for determining these values for cohesionless
soils.
PLANNING AND ORGANIZATION
Apparatus
1. Direct shear box apparatus
2. Loading frame (motor attached).
3. Dial gauge.
4. Proving ring.
5. Tamper.
6. Straight edge.
7. Balance to weigh upto 200 mg.
8. Aluminum container.
9. Spatula.
KNOWLEDGE OF EQUIPMENT:
Strain controlled direct shear machine consists of shear box, soil container, loading unit,
proving ring, dial gauge to measure shear deformation and volume changes. A two piece square
shear box is one type of soil container used.

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A proving ring is used to indicate the shear load taken by the soil initiated in the shearing plane.
PROCEDURE
1. Check the inner dimension of the soil container.
2. Put the parts of the soil container together.
3. Calculate the volume of the container. Weigh the container.
4. Place the soil in smooth layers (approximately 10 mm thick). If a dense sample is desired
tamp the soil.
5. Weigh the soil container, the difference of these two is the weight of the soil. Calculate the
density of the soil.
6. Make the surface of the soil plane.
7. Put the upper grating on stone and loading block on top of soil.
8. Measure the thickness of soil specimen.
9. Apply the desired normal load.
10.Remove the shear pin.
11. Attach the dial gauge which measures the change of volume.
12. Record the initial reading of the dial gauge and calibration values.
13. Before proceeding to test check all adjustments to see that there is no connection between
two parts except sand/soil.
14. Start the motor. Take the reading of the shear force and record the reading.
15.Take volume change readings till failure.
16. Add 5 kg normal stress 0.5 kg/cm2
and continue the experiment till failure
17. Record carefully all the readings. Set the dial gauges zero, before starting the experiment
DATA CALCULATION SHEET FOR DIRECT SHEAR TEST

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Normal stress 0.5 kg/cm2
L.C=....... P.R.C=.........
Horizontal
Gauge
Reading
(1)
Vertical
Dial
gauge
Reading
(2)
Proving
ring
Reading
(3)
Hori.Dial
gauge
Reading
Initial
reading
div.
gauge
(4)
Shear
deformation
Col.(4) x
Leastcount of
dial
(5)
Vertical
gauge
reading
Initial
Reading
(6)
Vertical
deformation=
div.in col.6
xL.C of dial
gauge
(7)
Proving
reading
Initial
reading
(8)
Shear stress =
div.col.(8)x proving
ring constant Area
of the
specimen(kg/cm2
)
(9)
0
25
50
75
100
125
150
175
200
250
300
400
500
600
700
800
900
Normal stress 1.0 kg/cm2
L.C=....... P.R.C=........

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Horizontal
Gauge
Reading
(1)
Vertical
Dial
gauge
Reading
(2)
Proving
ring
Reading
(3)
Hori.Dial
gauge
Reading
Initial
reading
div.
gauge
(4)
Shear
deformation
Col.(4) x
Leastcount of
dial
(5)
Vertical
gauge
reading
Initial
Reading
(6)
Vertical
deformation=
div.in col.6
xL.C of dial
gauge
(7)
Proving
reading
Initial
reading
(8)
Shear stress =
div.col.(8)x proving
ring constant Area
of the
specimen(kg/cm2
)
(9)
0
25
50
75
100
125
150
175
200
250
300
400
500
600
700
800
900
Normal stress 1.5 kg/cm2
L.C=....... P.R.C=........

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Horizontal
Gauge
Reading
(1)
Vertical
Dial
gauge
Reading
(2)
Proving
ring
Reading
(3)
Hori.Dial
gauge
Reading
Initial
reading
div.
gauge
(4)
Shear
deformation
Col.(4) x
Leastcount of
dial
(5)
Vertical
gauge
reading
Initial
Reading
(6)
Vertical
deformation=
div.in col.6
xL.C of dial
gauge
(7)
Proving
reading
Initial
reading
(8)
Shear stress =
div.col.(8)x proving
ring constant Area
of the
specimen(kg/cm2
)
(9)
0
25
50
75
100
125
150
175
200
250
300
400
500
600
700
800
900
OBSERVATION AND RECORDING
Proving Ring constant....... Least count of the dial........

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Calibration factor.......
Leverage factor........
Dimensions of shear box 60 x 60 mm
Empty weight of shear box........
Least count of dial gauge.........
Volume change.......
S.No
Normal load
(kg)
Normal
stress(kg/cm2)
load x
leverage/Area
Normal
stress(kg/cm2)
load x
leverage/Area
Shear stress
proving Ring
reading x
calibration /
Area of
container
1
2
3
GENERAL REMARKS
1. In the shear box test, the specimen is not failing along its weakest plane but
along a predetermined or induced failure plane i.e. horizontal plane separating
the two halves of the shear box. This is the main draw back of this test.
Moreover, during loading, the state of stress cannot be evaluated. It can be
evaluated only at failure condition i.e Mohrs circle can be drawn at the failure
condition only. Also failure is progressive.
2. Direct shear test is simple and faster to operate. As thinner specimens are
used in shear box, they facilitate drainage of pore water from a saturated
sample in less time. This test is also useful to study friction between two
materials one material in lower half of box and another material in the upper
half of box.
3. The angle of shearing resistance of sands depends on state of compaction,
coarseness of grains, particle shape and roughness of grain surface and

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grading. It varies between 28o
(uniformly graded sands with round grains in
very loose state) to 46o
(well graded sand with angular grains in dense state).
4. The volume change in sandy soil is a complex phenomenon depending on
gradation, particle shape, state and type of packing, orientation of principal
planes, principal stress ratio, stress history, magnitude of minor principal
stress, type of apparatus, test procedure, method of preparing specimen etc.
In general loose sands expand and dense sands contract in volume on
shearing. There is a void ratio at which either expansion contraction in volume
takes place. This void ratio is called critical void ratio. Expansion or
contraction can be inferred from the movement of vertical dial gauge during
shearing.
5. The friction between sand particle is due to sliding and rolling friction and
interlocking action.
The ultimate values of shear parameter for both loose sand and dense sand approximately
attain the same value so, if angle of friction value is calculated at ultimate stage, slight
disturbance in density during sampling and preparation of test specimens will not have much
effect.

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Experiment 8th
Standard Penetration Test
The Standard Penetration Test (SPT) is one type of in-situ soil test and It is conducted to
determine the geotechnical engineering properties of subsurface soils, especially for
cohesionless soil.
PT Test is most widely used to check various parameters and properties of soil on the
construction site. For any building foundation, design and construction soil testing are
essential.
The test is extremely useful for determining the bearing capacity, density, and angle of
shearing resistance of any soil. It can be used to determine the properties of cohesive and
cohesionless soil. The Standard Penetration Test ASTM e1105
Singnificance Soil Penetration Test :-
By performing a SPT test we can find out,
 Angel of shearing resistance of cohesionless soils.
 The relative density of cohesionless soils.
 Unconfined compressive strength of cohesive soils.
Purposes of SPT Geotechnical Test :-
The spt test is conducted mainly for two purposes,
 Soil sample to identify the type and nature of the soil at various depths.
 To determine penetration resistance of soil at various depths this is used for
geotechnical design purposes.
Standard Penetration Test Equipment
Following are the equipment used for the spt test,
1. Drilling Equipment
We can use any drilling equipment which provides a good and clean borehole, which is at
least 5mm larger than the Split Spoon Sampler.
2. Split Spoon Sampler
This is a thick-walled sample tube. The split spoon sampler has an outer diameter of it
is 50.8 mm and the inside diameter is 35 mm with a length of around 650 mm (26
inches).This tool has an assembly of a steel tube, coupling, driving shoes, a check valve, and
venting ports. Split spoon sampler collects only disturbed soil samples.

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3. Drop Hammer
This tool is used to drive the sampler into the borehole. The mass of it is 63.5 kg (140 lb).
4. Driving Head (Anvil)
It is used to stop the hammer on a certain point.
5. Guiding Rod
The Guiding rod just guides the hammer to the anvil.
Standard Penetration Test Procedure :-
Spt Test procedure on site as follows,
1. Dig Starting Bore Hole
First, dig the starting borehole with boring equipment.
Before conducting the test, we have to decide the total depth of penetration bore and depth
interval to carry the test and collect the sample the same. Let’s take borehole depth up to
10m. (Generally, depth of bore is up to groundwater table or up to hard strata below ground
surface.)
We can decide the intermediate test depth of every 1m. So, SPT is conducted at every one
meter of boring below ground level and soil samples are collected at the same depth.
2. Assemble the Sampler
Once boring of the hole is done up to desired depth (1 m depth we decided) remove the
drilling tools from the borehole and clean all the disturbed-materials.
After that fit the soil sampler named as split spoon sampler with the drilling rod and lower
into the borehole.
Now, rest split spoon sampler attracted with drilling rod at bottom of the drilled borehole of
undistributed soil.
3. Assemble Equipment
As we place sampler rest on the bottom of the borehole, it’s time to conduct the SPT test.
Keep ready test equipment the Hammer, Anvil and guiding rod and assemble them with each
other properly.

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Mark the distance of 150mm on the drilling rod to observe penetration details.
4. Conduct SPT Test
Firstly drive the drop hammer on the bottom of a borehole by blows from the slide hammer
with a mass of 63.5 kg falling through a distance of 750 mm (30 in) at the rate of 30
blows per minute.
Now, Count the numbers of blow required to reach or drive depth of 150 mm (6 in).
Similarly, again drive sampler in soil and count the blows needed to penetrate
the second and third 150 mm (6 in).

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In this test, the total sum of a number of blows required to drive sampler 150mm (6 in.) of
penetration is termed the “standard penetration resistance” or the “N-value“.
If the sampler is driven less than 450 mm (total), then the “N-value” shall be for the 300
mm of penetration (if less than 300 mm is penetrated, then report should specify the number
of blows and the depth penetrated).
If a number of blows required to drive the sampler to a depth of 150 mm excess the value 50,
it is considered as a refusal and the test is discontinued.
The entire sampler may sometimes sink under its own weight when a very soft sub-soil
stratum is encountered. Under such situations, it may not be necessary to give any blow to the
sampler and “N-value” should be indicated as zero.
The Test shall be made at every change in the stratum or at intervals of not more than 1.5
meter whichever is less. The test may be made at lesser intervals if necessary or specified.
5. Soil Sample Collection
Now, collect the soil sample from the borehole,
 Take out a spilt sampler from the borehole.
 Carefully, separate the split spoon sampler from the drilling rod and remove any
excess soil from the bottom, also drain water if it contains.
 Slowly open the one side of the split spoon sampler to expose fresh material and any
stratification.
 Record the length, composition, color, stratification, and condition of the sample.
 Remove soil specimen from split spoon sampler and pack it in a plastic bag.
How to Find Bearing Capacity of Soil from SPT Test Result
The following are the step to find the bearing capacity of soil from SPT Values or standard
penetration test calculation.
Step: 1 Take Average of Penetration Value
Make necessary correction SPT values and take an average of corrected SPT values from the
base level of foundation to a depth equal to 2 times the width of the foundation.
Step: 2 Find our Angle of Shearing Resistance
Find out the angle of sharing resistance by correlating the above SPT values from a given
graph.

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Step: 3 Find out Effective Surcharge
Find out the value of effective surcharge by multiplying the effective unit weight of soil with
the depth of the foundation i.e.
q = ϒ*Df
Where,
q = Effective surcharge at foundation base level, in kgf/cm2
ϒ = Unit weight of soil, in kgf/cm3
Df = Depth of foundation, in cm
Step: 4 Find out Bearing Capacity Factor
Calculate out the corresponding values of bearing capacity factors (i.e. Nq & Nϒ) by
correlating the values of angle of shearing resistance from the table given below. For any
intermediate value of ‘ϕ’, make linear interpolation.

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Step: 5 Find Out Shape Factor
Calculate shape factors (i.e. sq & sϒ) using the formula given below.
Where,
B = Width of foundation, in cm
L = Length of foundation, in cm
Step: 6 Find Out Depth Factor
Calculate depth factors (i.e. dq & dϒ) using the following formula.
dq=dϒ=1 (for ϕ < 100)

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dq = dϒ = 1+0.1(Df/B)(Nϕ)1/2 (for ϕ>100)
Nϕ is calculated using the following formula
Nϕ = tan2[(π/4)+(ϕ/2)]
Step: 7 Calculate Inclination Factor
Calculate inclination factors (i.e. iq & iϒ) using the formula given below
Where,
α = Load inclination to the vertical in degrees
ϕ = Angles of shearing resistance in degrees
Step: 8 Calculate Correction Factor
Find out correction factor for the location of the water table using the following formula
W’ = 0.5+0.5[Dw/(Df+B)]
Where,
W’ = Water table correction factor
Dw = Depth of water table, in cm
Df = Depth of foundation, in cm
Step: 9 Calculate Bearing Capacity of Soil:
Calculate net ultimate bearing capacity by using the below equation.

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Where,
qd = It is Net ultimate bearing capacity of foundation (kgf/cm2)
q = Effective surcharge at base level of foundation, in kgf/cm2 (Refer step-3)
Nq & Nϒ = Bearing capacity factors (Refer step-4)
sq & sϒ = Shape factors (Refer step-5)
dq & dϒ = Depth factors (Refer step-6)
iq & iϒ = Inclination factors (Refer step-7)
W’ = Correction factor for the location of the water table (Refer step-8)
B = Width of foundation, in cm
ϒ = Foundation soil bulk unit weight, in kgf/cm3.
Soil Penetration Test
The Standard Penetration Test (SPT) is one type of in-situ soil test and It is conducted to
determine the geotechnical engineering properties of subsurface soils, especially for
cohesionless soil. SPT Test is most widely used to check various parameters and
properties of soil on the construction site. For any building foundation, design and
construction soil testing are essential.
Standard Penetration Test Equipment
SPT Test required following equipment,
Drilling Equipment
Split Spoon Sampler
Drop Hammer
Driving Head (Anvil)
Guiding Rod
Standard Penetration Test Procedure
SPT test procedure as follows,
1. Dig Starting Bore Hole up to 1m first..

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2. Assemble the Sampler: Fit the soil sampler named as split spoon sampler with the drilling
rod and lower it into the borehole.
3. Assemble Equipment: Keep ready test equipment the Hammer, Anvil and guiding rod
and assemble them with each other properly.
4. Conduct SPT Test: Firstly drive the drop hammer on the bottom of a borehole by blows
from the slide hammer with a mass of 63.5 kg falling through a distance of 750 mm (30
in) at the rate of 30 blows per minute. Count the numbers of blow required to reach or drive
depth of 150 mm (6 in).
5. Soil Sample Collection: Now, collect the soil sample from the borehole,
What Is n Value
The number of blows required by hammer to dig 30 cm depth in SPT test is known as N-
Value of Soil. The measured N-value is also called standard penetration resistance of the
soil.
SPT Test IS Code
The standard penetration test conducted as per IS -2131:1963