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  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 0

    Smt. S. R. PATEL ENGINEERING COLLEGE Dabhi, unjha- 384170

    Department of CIVIL engineering

    Subject : GEOTECHNICAL ENGINEERING-ii

    Subject code: 160606

    EXP

    ERIM

    ENTS

    IN G

    EOTE

    CH

    NIC

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    ENG

    INEE

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  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 1

    INDEX

    No. Experiment Page No. Date Sign

    1. Auger Boring and Sampling

    2. Standard Penetration Test

    3. Permeability Test: Constant Head

    4. Permeability Test: Falling Head

    5. Free Swell and Swell Potential

    6. Swelling Pressure Test

    7. Model Pile Driving and Pile Load Test

  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 2

    Experiment 1 Date:

    AUGER BORING AND SAMPLING

    IS 1892 : 1979

    AIM: To collect soil sample using Auger Boring

    APPARATUS:

    1. Hand operated Auger (75 mm dia.)

    2. drilling rods

    3. guiding plates

    4. trowels.

    PROCEDURE:

    The hand augers used in boring are about 15 to 20 cm in diameter. These are suitable for

    advancing holes up to a depth of 3 to 6m in soft soils. The hand auger is attached to the lower end of a

    pipe of about l8mm diameter. The pipe is provided with a cross-arm at its top. The hole is advanced by

    turning the cross-arm manually and at the same time applying thrust in the downward direction. When

    the auger is filled with soil, it is taken out and for the required depth the disturbed samples are

    preserved in order to determine required physical properties. If the hole is already driven, another type

    of auger, known as post hole auger is used for taking soil samples.

    THEORY:

    An auger is a boring tool similar to one used by a carpenter for boring holes in wood. It consists

    of shank with a cross-wise handle for turning and having central tapered feed screw. The augers can be

    operated manually or mechanically. Mechanical augers are driven by power. These are used for

    making holes in hard strata to a great depth. However, for depths greater than 12m, even mechanical

    augers become inconvenient and other methods of boring are used. Continuous flight augers are

    special type of mechanical augers which are provided with a central hollow tube. When the hole is

    advanced, the central tube is kept plugged. As the auger is turned into the ground, the cuttings rise to

    the surface through the spiral. During sampling, the plug is removed and a sampler is inserted for

    taking the samples. The main disadvantage of using a continuous flight auger is that it becomes

    difficult to ascertain the depth from which the cutting coming on the ground have been removed.

    Auger boring is generally used in soils which can stay open without casing or drilling mud.

    Clays, silts and partially saturated sands can stand unsupported. For soils which cannot stand

    unsupported, especially for sandy soils below water table, a casing is normally required. For such

  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 3

    soils, the method of auger boring becomes slow and expensive. Auger boring cannot be used when

    there are large cobbles, boulders or other obstructions which prevent drilling of the hole, Auger

    borings are particularly useful for subsurface investigations of highways, railways and air fields, where

    the depth of exploration is small. The investigations are done quite rapidly and economically by auger

    boring. The main disadvantage of the auger boring is that the soil samples are highly disturbed.

    Further, it becomes difficult to locate the changes in the soil strata.

    BORE LOG Date of Boring: Location of Boring :

    Boring No.: Type of Boring:

    Water Table: Type of Sampler:

    Soil

    Description

    Soil

    Inden-

    tification

    Depth of

    Strata

    Sample

    Type

    (%)

    L

    (%)

    P

    (%)

    S

    (%) G

    Cu

    Kg/

    cm2

  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 4

    Water Content Determination by oven drying method for depth, in m =

    Sr. No. Description Sample-l Sample-2

    1 Container No.

    2 Mass of container and wet soil W2, in g

    3 Mass of container and dry soil W3, in g

    4 Mass of container WI, in g

    5 Mass of dry soil (W3- WI), in g

    6 Mass of moisture (W2- W3), in g

    7 Water content co = W2W3

    W3Wl xl00, In %

    8 Average water content, in %

    Liquid Limit Determination by cone penetration method for depth, in m =

  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 5

    Specific Gravity of soil for depth in m=

    Room trmperature t0

    C=

    1 2 3

    1 Weight of density

    bottle W1 g

    2 Weight of density

    bottle + dry soil W2 g

    3 Weight of density

    bottle + dry soil +

    water W3 g

    4 Weight of density

    bottle + water W4 g

    5 Specific gravity of soil

    G=___(W2- W1)_____

    (W4W1) (W3 W2) G

    Average sp. Gravity of soil at Tt

    Average sp. Gravity of soil at 27O

    c

    Particle size distribution sheet for depth in m=

    Mass of dry soil sample in g=

    Sr.

    no.

    IS

    Sieve

    Particle size

    (mm)

    Mass

    retained

    (g)

    %

    Retained

    Cumulative

    % retained

    Cumulative

    % finer

    (N)

    1 4.75 mm

    2 2.36 mm

    3 1.18 mm

    4 600

    5 425

    6 300

    7 150

    8 75

  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 6

    Determination of Shear Parameters for the depth, in m:

    Cross-sectional area of the specimen, cm2:

    Bulk Density of soil:

    Sr.No. Normal

    Stress,Kg/cm2

    Proving Ring

    Reading (div)

    Shear

    Force,kg Shear Stress,kg/cm2

    cu,

    kg/cm2

    Conclusion:

    Sign

  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 7

    Experiment 2 Date:

    STANDARD PENETRATION TEST

    IS :2131-1981

    AIM: To determine the resistance of soil against penetration

    APPARATUS:

    1. Tripod

    2. manila rope

    3. doughnut hammer of weight 63.5kg

    4. anvil

    5. split spoon sampler

    6. driving rod.

    PROCEDURE:

    The standard penetration test is conducted in a bore hole using a standard split- spoon

    sampler. when the bore hole has been drilled to the desired depth, the drilling tools are removed

    and the sample is driven into the soil by a drop hammer of 63.5kg mass falling through a height

    of 750mm at the rate of30 blows per minute (IS: 2131-1963).the number of hammer blows

    required to drive 150mm of sample is counted. The sample is further driven by 150 mm and the

    number of blows recorded. Likewise, the sampler is once again further driven by 150 mm and

    number of blows recorded. The number of blows recorded for the first 150 mm is disregarded.

    The number of blows recorded for the last two 150 mm intervals are added to give standard

    penetration number (N).in other words, the standard penetration number is equal to the number

    of blows required for 300 mm penetration beyond a seating drive of 150 mm. If the number of

    blows for 150 mm drive exceeds 50, It is taken as refusal and test is discontinued. If the split spoon

    sampler is driven less than 45cm (total), then the penetration will be for the last 30cm of

    penetration (if less than 30cm is penetrated, the logs should state the number of blows and the

    depth of penetration.

    THEORY:

    The standard penetration test is most commonly used in in-situ test, especially for

    cohesion-less soils which cannot be easily sampled. The test is extremely useful for determining the

    relative density and the angle of shearing resistance of cohesion-less soils. It can also be used to

    determine the unconfined compressive strength of cohesive soils.

    The standard penetration number is corrected for dilatancy correction and overburden correction

    and overburden correction as explained below.

  • Experiments in Geotechnical Engineering - II: Semester VI

    Civil Engineering, S. R. Patel Eng. College, Dabhi Page 8

    (a) Dilatancy correction: Silty fine sand and fine sand below the water t

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