code no: 09a50104 r09 set-1 - skyupsmediablog...8.a) what are the advantages and disadvantages of...

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R09Code No: 09A50104 SET-1 B. Tech III Year I Semester Examinations, December-2011

GEOTECHNICAL ENGINEERING-I (CIVIL ENGINEERING)

Time: 3 hours Max. Marks: 75 Answer any five questions

All questions carry equal marks ---

1.a) Derive from fundamentals: es = Gw, where ‘s’ represents degree of saturation,

‘e’ represents void ratio, ‘w’ represents water content, and ‘G’ represents grain specific gravity.

b) The dry unit weight of a sand sample in the loosest state is 13.34 kN/m3 and in the densest state, it is 21.19 kN/m3. Determine the density index of this sand when it has a porosity of 33%. Assume the grain specific gravity as 2.68. [7+8]

2. a) Define and distinguish the following in terms of their use in soil engineering:

i) Consistency Index and Liquidity Index ii) Flow Index and Toughness Index

b) A soil sample has a liquid limit of 20% and plastic limit of 12%. The following data are also available from sieve analysis:

Sieve Size (mm) 2.0 0.425 0.075 % Passing 100 85 38

Classify the soil approximately according to Indian Standard Classification. [7+8] 3. a) Define and distinguish the following:

i) adsorbed & absorbed water ii) Discharge velocity & Seepage velocity. b) A bed of sand consists of three horizontal layers of equal thickness. The

magnitude of the coefficient of permeability for both the upper and lower layer is 7 x 10-5 mm/s and for the middle layer is 3 x 10-3 mm/s. What is the ratio of the average permeability of the bed in the horizontal direction to that in the vertical direction? [7+8]

4. a) Demonstrate the quick sand condition with a neat sketch and derive the

expression for critical hydraulic gradient. b) An earth dam of 80 m wide is built on an impervious foundation with a horizontal

filter at the base near the toe. The permeability of the soil in the horizontal and vertical directions is 8 x 10-3 mm/s and 2 x 10-3 mm/s respectively. The full reservoir level is 40 m above the filter. A flow net constructed for the transformed section of the dam, consists of four flow channels and 12 head drops. Estimate the seepage loss for the entire length of dam. [7+8]

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5. a) Discuss the construction of Newmark’s influence chart for vertical stress

estimation. b) A light house is constructed on a circular ring type foundation. The intensity of

loading on the foundation is 200 kPa. The outer diameter of the ring foundation is 16m and the internal diameter is 12m. Determine the vertical pressure directly below the centre of the foundation at depths of 4m and 6m. [7+8]

6. a) Write brief notes on ‘compaction’ and ‘consolidation’ of soils and differentiate

the two. b) Discuss how quality control of compacted earth mass is ensured in the in-situ.

[7+8] 7. a) Define the following:

i) Under consolidated soil ii) Normally consolidated soil and iii) Over consolidated soil. Also discuss the reasons for over consolidation of soil.

b) There is a bed of compressible clay of 4 m thickness with pervious sand on top and impervious rock at the bottom. Consolidation test conducted on an undisturbed specimen of clay of 20 mm thick obtained from the same deposit showed that 90% settlement has reached in 4 hours. Estimate the time in years for the building founded over this deposit to reach 90% of its final settlement. [7+8]

8. a) What are the drained and undrained shear tests? Under what conditions should the

drained shear strength or the undrained shear strength parameters are used? Explain.

b) The following results were obtained at failure in series of triaxial compression tests, on specimens of clay. Determine the values of shear strength parameters c and φ either by drawing the Mohr circles or analytically. [7+8]

Confining Pressure (σ3), kPa 150 300 450 Deviator Stress (σd), kPa 192 341 504

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1.a) Define and write the suitable expressions for the following terms: (i) saturated unit weight (ii) bulk unit weight (iii) dry unit weight and (iv) unit weight of solids.

b) The porosity of a soil sample is 40% and the specific gravity of its particles is 2.65. Calculate its void ratio, dry unit weight, saturated unit weight and submerged unit weight. Also calculate the bulk unit weight of soil, if its degree of saturation is 60%. [7+8]

2.a) Define and distinguish the following: (i) liquidity index & consistency index and

(ii) uniformly graded soil & well graded soil. b) A certain soil has 99% by weight finer than 1mm, 80% finer than 0.1mm, 25%

finer than 0.01mm and 8% finer than 0.001mm. Sketch the grain size distribution curve and determine the % of sand as per the IS nomenclature. Also determine the Hazen’s effective size and uniformity coefficient. [7+8]

3.a) What is permeability? Discuss the various factors that affect the permeability of

soil. b) A sample in a variable head permeameter is 100 mm in diameter and 120 mm

high. The permeability of the sample estimated to be 10 x 10-4 mm/s. if it is desired that the head in the stand pipe should fall from 250 mm to 100 mm in 180 s, determine the size of the stand pipe which should be used. [7+8]

4.a) Define (i) total stress, (ii) effective stress, (iii) pore water pressure and

(iv) capillary rise. b) At a given site, the water table is located at the ground surface and the submerged

unit weight of soil is 8 kN/m3. If water table rises 4m above the ground surface, determine the change in effective stress at 6m below the ground surface. [7+8]

5.a) Discuss the assumptions in Boussinesq’s and Westergaard’s stress distribution

theories. Define pressure bulb and explain its importance in soil engineering. b) An annular circular raft has outer and inner diameters as 24m and 18m

respectively. If the load intensity on the raft is 250 kPa, estimate the increase in vertical stress at a depth of 2m and 4m from the ground surface and exactly below the centre of the raft. [7+8]

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6.a) What is soil compaction? Discuss the various factors that affect the compaction of soil.

b) Write a note on various in-situ compaction equipment and their suitability to soils. [7+8]

7.a) Define the following: (i) primary consolidation settlement (ii) degree of

consolidation (iii) compression index and (iv) maximum drainage path in double drainage system.

b) What is coefficient of consolidation of soil? Discuss its evaluation procedure with the help of ‘square root time fitting method. [7+8]

8. a) What are the various drainage tests in triaxial compression? Discuss failure

envelopes of UU, CU and CD tests for saturated clays, normally consolidated and over consolidated clays.

b) A cylindrical specimen of a saturated soil fails under an axial stress of 150 kPa in an unconfined compression test. The failure plane makes an angle of 550 with the horizontal. Calculate the cohesion and angle of internal friction of the soil. [7+8]

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1.a) Defining the terms void ratio, degree of saturation and water content, explain the

engineering significance of determining these properties. b) The dry unit weight of a sand sample in the loosest state is 13.5 kN/m3 and in the

densest state, it is 21.2 kN/m3. Determine the density index of this sand when it has a porosity of 35%. Assume the grain specific gravity as 2.65. [7+8]

2.a) Discuss the classification of fine grained soils using IS plasticity chart. b) A sieve analysis on a soil sample gave the following results:

Sieve size (mm) 4.75 2.0 0.84 0.42 0.25 0.15 0.075

% Finer 65 55 44 30 24 15 9 Sketch the grain size distribution curve and determine the coefficient of uniformity and coefficient of curvature. [7+8]

3.a) Discuss the suitable laboratory method to determine coefficient of permeability of coarse grained soils.

b) Determine the average horizontal and vertical permeability of a soil mass made up of three horizontal strata, each 2m thick, if the coefficient of permeability are 2 x 10-2 mm/s, 4 x 10-2 mm/s, and 4 x 10-3 mm/s for the three layers. [7+8]

4.a) What is flownet? Discuss the characteristics and uses of flownets. b) For a homogeneous earth dam having water head 30m, a flow net was constructed

with four flow channels. The number of potential drops was 16. The dam has a horizontal filter at the base near the toe. The coefficient of permeability of the soil was 4x10-4 mm/s. Determine the anticipated seepage, if the length of the dam is 120m. [7+8]

5. Discuss the assumptions of Boussinesq’s theory. Using Boussinesq’s expression,

derive the expression for vertical stress at depth ‘z’ under the centre of a circular area of radius, ‘r’ loaded uniformly with a load ‘q’ at the surface of the mass of soil. [15]

6.a) Explain why soils are compacted in the field. Discuss how the degree of compaction or relative compaction is is ensured in the field?

b) Explain how zero air void line (ZAVL) is constructed and write its significance in compaction of soil. [7+8]

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7.a) Define the following: (i) immediate settlement (ii) primary consolidation settlement (iii) secondary consolidation settlement and (iv) over consolidation ratio.

b) A 2 cm thick sample of clay was taken from field for predicting the times of settlement for a proposed building which exerts a uniform pressure of 200 kN/m2 over the clay stratum. The sample was loaded to 200 kN/m2 and proper drainage was allowed from top and bottom. It was seen that 50% of the total settlement occurred in 180 seconds. Find the time required for 50% of the total settlement of the building if it is to stand on 8m thick layer of clay which extends from ground surface and is underlain by sand. [7+8]

8.a) What are the advantages and disadvantages of triaxial compression test over direct shear test? Explain.

b) The following data relate to a triaxial compression tests performed on a soil sample.

Test No. Cell Pressure (σ3), kPa Maximum Deviator Stress (σd), kPa

1 80 175 2 150 240 3 210 300

Determine the shear parameters such as cohesion and angle of internal friction from the above data using the relation of σ1 and σ3. [7+8]

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1.a) What are the index and engineering properties of soil? Discuss the various structures of soil.

b) A sample of saturated soil has a water content of 40%. The specific gravity of solids is 2.65. Determine its void ratio, porosity, saturated unit weight and dry unit weight. [7+8]

2.a) Define and distinguish the following in terms of their use in soil engineering:

i) Liquid Limit and Liquidity Index ii) Density and Relative Density

b) A certain soil has 99% by weight finer than 1mm, 80% finer than 0.1mm, 25% finer than 0.01mm and 8% finer than 0.001mm. Sketch the grain size distribution curve and determine the % of sand as per the IS nomenclature. Also determine the Hazen’s effective size and uniformity coefficient. [7+8]

3.a) Discuss the following: (i) discharge velocity (ii) seepage velocity (iii) principle of Darcy’s law and (iv) effect of void ratio on permeability of soil

b) A sample in a variable head (falling head) permeameter is 10cm in diameter and 10cm high. The permeability of the sample is estimated to be 4x10-4 cm/s. If it is desired that the head in the stand pipe should fall from 25cm to 12cm in 200 seconds, determine the size of the stand pipe which should be used. [7+8]

4.a) What is flownet? Write the principles and uses of flow nets.

b) A sand deposit of 12m thick is lying above the soft clay bed. The water table is 4m below the ground surface. If the sand above the ground water table has 50% degree of saturation, calculate the effective stress at the middle and bottom of the sand layer. [7+8]

12m

Soft clay

4m Sand, s = 50%, e = 0.6, G = 2.65 Ground Surface

Sand, s = 100%, e = 0.6, G = 2.65

5.a) Explain the use of ‘Newmark’s influence chart’ in vertical stress estimation in

case of irregularly loaded areas.

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b) A raft of the size 4mx4m carries a uniform load of 180 kN/m2. Using the point load approximation with four equivalent point loads, calculate the stress increment at a point in the soil which is 4m below the centre of the loaded area.

[7+8]

6.a) Write a note on (i) zero air void line (ii) degree of compaction (iii) OMC and MDD and (iv) uses of compaction of soil.

b) Discuss various factors affecting the compaction of soil. [7+8] 7.a) What is preconsolidation pressure? Explain the Casagrande’s graphical procedure

for its estimation. b) At a given site (site A) having a clay layer 4m thick with single drainage, a

uniform fill that was constructed resulted in a settlement of 25 mm in 1 year, corresponding to 50% average degree of consolidation. It was found that at a neighboring site (site B), the same type of clay of thickness 9m exists with single drainage. How long will it take for 50% consolidation to occur? [7+8]

8.a) What are the three standard triaxial shear tests with respect to drainage conditions? Explain with reasons the situations for which the each test is preferred.

b) A series of box shear (area of box = 36 cm2) tests were conducted on a soil sample. For the results presented in below table, estimate the ‘cohesion’ and ‘angle of internal friction’ of soil. [7+8]

Normal load (N) 90 180 270 Shear load (N) 70 90 117

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INSTITUTE OF AERONAUTICAL ENGINEERING (Aproved by AICTE, New Delhi, Accreditated by NBA, New Delhi & Affliated to JNTU, Hyderabad)

Dundigal, Hyderabad -500 043. Web: [email protected], 08418-257181/182/200, [email protected]

____________________________________________________________________________________________________________________ II MID TERM EXAMINATIONS – November 2013

Course: III Year B. Tech – I Sem Branch: Civil Subject: Geotechnical Engineering-I Date of Exam: 05-11-2013(FN) Duration: One hour Max. Marks: 10

Note: 1. Answer any two questions

SET-1

1 a) What are the assumptions made by Boussinesq and Westrgaard for point load solutions? [3M]

b) Give the formulae for the Boussinesq and Westergard solutions. [2M]

2 a) What are the various factor affecting the compaction of soil? [2M]

b) By light compaction the maximum dry density obtained is 1. 78 g/ ml at OMC of 15 %. Find the air

voids and degree of saturation. [3M]

3 a) What do you understand by intial, primary and secondary consolidation? [2M]

b) The laboratory consolidation data for an undisturbed clay sample are as follows.e1=1, €1=85 k N/m2,

e2=0.80, €2= 465 kN/m 2, . Determine the void ratio for a pressure €3= 600 k N/m2. [3M]

4 a) What are the tests used for determining the shear strength and explain briefly? [3M]

b) What is shear strength of soil along a horizontal plane at a depth of 4 m in sand deposit having the

following properties?

Angle of internal friction Ø = 350; dry unit weight = 17 kN /m3; Specific gravity = 2.7

Assume that the ground table is at a depth 2.5 m from the ground surface. [2M]

mailto:[email protected]







SET-2

1 a) Describe the Newmarks influence chart [2M]

b)A ring footing of an external diameter 8m and internal diameter 4m rests at a depth 2m below the

ground surface carried a load of 150 k N/ m2. Find the vertical stress at depths 2m , 4m, and 8m along

the axis of footing base, neglect the effect of excavation on the stress. [3M]

2 a) Write notes on proctor needle [2 M]

b) The following results were obtained in compaction test. Determine the OMC and maximum dry

density.

Test No. 1 2 3 4 5 6

Wet unit weight k N / m2 18.81 20.07 20.52 21.05 21.06 20.07

Water content % 7.4 7.9 10.5 11.5 13.1 14.4

3 a ) How do you determine the pre consolidation pressure based on the laboratory test and how e- log p

curve used . by whom it was proposed. [2M]

b) a recently completed fill was 100m thick and its initial average void ratio is 1. After some months the

embankment was constructed and at this time the void ratio is 0.80. Estimate the compression of this fill.

[3M]

4 a ) Describe the Mohr s circle. [2M]

b) Director shear test was conducted on a dry sand sample. The size of the sample was used for the

test is 36 cm2 area under drained conditions, The following results were obtained.

Normal load (Kg) 9 18 27 45

Maximum shear force (Kg) 12.5 15.5 18.5 25.5

Plot a failure envelope for the soil and determine the values of apparent angle of shear resistance and

apparent cohesion. [3M]








SET-3

1 a) Describe pressure isobar [2 M]

b) A circular area on surface of an elastic mass of great extent carries a uniformly distributed load of 15

tons per m2. The radius of the circular are is 4m. Compute the vertical normal stress at a point 6m

beneath the centre of the circle using the Boussinesqs eqation. [3M]

2 a) Write down what are zero air voids line and saturation line [2 M]

b) Compaction test results are as follows.

Trail No Moisture content % Wet wt of compacted soil

By dry wt k N/ m3

1 10.5 0 21.30

2 13.4 0 21.20

3 13.80 20.80

Specific gravity is 2.65. Determine the optimum water content. Draw zero air voids curve and 90%

moisture water content curve. [3M]

3 a) Describe the method for determination of Cv. Whose method you followed [2M]

b) An odometer test was performed on 4 cm thick clay sample. After 10 minutes 50% consolidation is

attained, how many days it will take to attain same degree of consolidation where the clay layer is 4 m

thick having double drainage condition. [3M]

4 a) Write down the stress- strain behavior of sands. [2 M]

A series of shear tests were conducted on soil. Each test was carried out until the sample sheared and the

principle stresses for each test were as follows.

Test σ3 (kN /m2) σ1 (kN/m2)

1 200 600

2 300 900

3 400 1200

Plot the Mohr’s circle. Determine the strength envelope and angle of internal friction of the soil. [3M]








SET-4

1 a) Derive an expression for the load acting along the edge of loaded rectangular area. [2M]

b) A load of 1000kN is uniformly distributed on a surface area of 3x 2.5m2. Find the value of vertical

normal stress at a depth of 2 m equivalent point load method. [3M]

2 a) Differentiate between compaction and consolidation [2M]

b) The following results were obtained for proctor test on soil sample.

Water content % 7.7 11.5 14.6 17.5 19.7 21.2

Mass of wet soil kg 1.7 1.89 2.03 1.99 1.96 1.92

Specific gravity is 2.65 and the mould used is 950cc.Find out optimum moisture content and max dry

density. [3M]

3 a) Write notes on settlement from e-p curves. [2M]

b) A soil sample has compression index 0.3. If the void ratio at stress is 141 kN / m2 is 0.5. Compute the

void ratio if the stress is increased to 201 kN/m2. Determine the settlement of a soil stratum 4m thick.

[3M]

4 a) List out types of tri -axial compression tests. [3M]

b) Given €1 = 600kN / m2 and €3 = 200kN / m2. Determine the maximum shear and maximum

obliquity and stress acting on them. [3M]








SET-1

1 a) What are the assumptions made by Boussinesq and Westrgaard for point load solutions? [3M]

b) Give the formulae for the Boussinesq and Westergard solutions. [2M]

2 a) What are the various factor affecting the compaction of soil? [2M]

b) By light compaction the maximum dry density obtained is 1. 78 g/ ml at OMC of 15 %. Find the air

voids and degree of saturation. [3M]

3 a) What do you understand by intial, primary and secondary consolidation? [2M]

b) The laboratory consolidation data for an undisturbed clay sample are as follows.e1=1, €1=85 k N/m2,

e2=0.80, €2= 465 kN/m 2, . Determine the void ratio for a pressure €3= 600 k N/m

2. [3M]

4 a) What are the tests used for determining the shear strength and explain briefly? [3M]

b) What is shear strength of soil along a horizontal plane at a depth of 4 m in sand deposit having the

following properties?

Angle of internal friction Ø = 350; dry unit weight = 17 kN /m

3; Specific gravity = 2.7

Assume that the ground table is at a depth 2.5 m from the ground surface. [2M]








SET-2

1 a) Describe the Newmarks influence chart [2M]

b)A ring footing of an external diameter 8m and internal diameter 4m rests at a depth 2m below the

ground surface carried a load of 150 k N/ m2. Find the vertical stress at depths 2m , 4m, and 8m along

the axis of footing base, neglect the effect of excavation on the stress. [3M]

2 a) Write notes on proctor needle [2 M]

b) The following results were obtained in compaction test. Determine the OMC and maximum dry

density.

Test No. 1 2 3 4 5 6

Wet unit weight k N / m2

18.81 20.07 20.52 21.05 21.06 20.07

Water content % 7.4 7.9 10.5 11.5 13.1 14.4

3 a ) How do you determine the pre consolidation pressure based on the laboratory test and how e- log p

curve used . by whom it was proposed. [2M]

b) a recently completed fill was 100m thick and its initial average void ratio is 1. After some months the

embankment was constructed and at this time the void ratio is 0.80. Estimate the compression of this fill.

[3M]

4 a ) Describe the Mohr s circle. [2M]

b) Director shear test was conducted on a dry sand sample. The size of the sample was used for the

test is 36 cm2 area under drained conditions, The following results were obtained.

Normal load (Kg) 9 18 27 45

Maximum shear force (Kg) 12.5 15.5 18.5 25.5

Plot a failure envelope for the soil and determine the values of apparent angle of shear resistance and

apparent cohesion. [3M]








SET-3

1 a) Describe pressure isobar [2 M]

b) A circular area on surface of an elastic mass of great extent carries a uniformly distributed load of 15

tons per m2. The radius of the circular are is 4m. Compute the vertical normal stress at a point 6m

beneath the centre of the circle using the Boussinesqs eqation. [3M]

2 a) Write down what are zero air voids line and saturation line [2 M]

b) Compaction test results are as follows.

Trail No Moisture content % Wet wt of compacted soil

By dry wt k N/ m3

1 10.5 0 21.30

2 13.4 0 21.20

3 13.80 20.80

Specific gravity is 2.65. Determine the optimum water content. Draw zero air voids curve and 90%

moisture water content curve. [3M]

3 a) Describe the method for determination of Cv. Whose method you followed [2M]

b) An odometer test was performed on 4 cm thick clay sample. After 10 minutes 50% consolidation is

attained, how many days it will take to attain same degree of consolidation where the clay layer is 4 m

thick having double drainage condition. [3M]

4 a) Write down the stress- strain behavior of sands. [2 M]

A series of shear tests were conducted on soil. Each test was carried out until the sample sheared and the

principle stresses for each test were as follows.

Test σ3 (kN /m2) σ1 (kN/m

2)

1 200 600

2 300 900

3 400 1200

Plot the Mohr’s circle. Determine the strength envelope and angle of internal friction of the soil. [3M]








SET-4

1 a) Derive an expression for the load acting along the edge of loaded rectangular area. [2M]

b) A load of 1000kN is uniformly distributed on a surface area of 3x 2.5m2. Find the value of vertical

normal stress at a depth of 2 m equivalent point load method. [3M]

2 a) Differentiate between compaction and consolidation [2M]

b) The following results were obtained for proctor test on soil sample.

Water content % 7.7 11.5 14.6 17.5 19.7 21.2

Mass of wet soil kg 1.7 1.89 2.03 1.99 1.96 1.92

Specific gravity is 2.65 and the mould used is 950cc.Find out optimum moisture content and max dry

density. [3M]

3 a) Write notes on settlement from e-p curves. [2M]

b) A soil sample has compression index 0.3. If the void ratio at stress is 141 kN / m2 is 0.5. Compute the

void ratio if the stress is increased to 201 kN/m2. Determine the settlement of a soil stratum 4m thick.

[3M]

4 a) List out types of tri -axial compression tests. [3M]

b) Given €1 = 600kN / m2 and €3 = 200kN / m

2. Determine the maximum shear and maximum

obliquity and stress acting on them. [3M]



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JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD

B. Tech III Year I Semester Examinations, November/December - 2012 GEOTECHNICAL ENGINEERING - I

(Civil Engineering) Time: 3 hours Max. Marks: 75

Answer any five questions All questions carry equal marks

----

1.a) What is three phase diagram? Explain how it changes in dry soil and saturated soils? b) An undisturbed sample of soil has a volume of 100 cm3 and mass of 190 g. On oven drying for 24 hours, the mass is reduced to 160 g. If the specific gravity of grains is 2.68, determine the bulk and dry unit weights, water content, voids ratio and degree of saturation of the soil. [5+10] 2. Explain the method of classifying the coarse grained soil by IS classification. [15] 3.a) Derive an expression to determine coefficient of permeability of soil by laboratory falling head permeability test. b) During a permeability test on a soil sample with falling head permeability, equal

time intervals are noted for drops of head from h1 to h2 and again from h2 to h3. Find a relationship between h1, h2 and h3. [10+5]

4.a) Compute the total, effective and pore pressure at a depth of 15m below the bottom

of a lake 6m deep. The bottom of the lake consists of soft clay with a thickness of more than 15m. The average water content of the clay is 40% and the specific gravity of soils may be assumed to be 2.72.

b) Write short notes on quick sand condition. [10+5] 5.a) What are the assumptions made by Boussinesq’s in deriving the expression for

stress in soil due to a point load on the ground surface? b) Find the intensity of vertical pressure at a point 4m directly below a 20 kN point

load acting at a horizontal ground surface. What will be the vertical pressure at a point 2m horizontally away from the axis of loading but at the same depth of 4m and directly under the load at a depth of 3m? [5+10]

R09 Code No: 09A50104

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6. A proctor compaction test was conducted on a soil sample and the following observations were made.

If the volume of the mould used was 950cc and the specific gravity of the soil was

2.65. (i) draw the dry density vs moisture content curve (ii) also plot the zero air voids line (iii) Find the optimum moisture content and maximum dry density of soil (iv) also find the degree of saturation at OMC. [15]

7.a) Explain the graphical method to determine the pre-consolidation pressure. b) An undisturbed sample of clay stratum, 2m thick, was tested in laboratory and the average value of coefficient of consolidation was found to be 2 x 10-4 cm2/s. If a structure is built on the clay stratum, how long will it take to attain half the ultimate settlement under the load of the structure? Assume double drainage. [7+8] 8.a) Explain the triaxial shear tests based on drainage conditions. b) The results of two drained triaxial tests on saturated clay are given as . Specimen I: Horizontal Confining Stress = 70 kN/m2 Deviator Stress = 213 kN/m2 Specimen II: Horizontal Confining Stress = 100 kN/m2 Deviator Stress = 250 kN/m2 Calculate shear strength parameters of the soil. [7+8]

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Water Content (%) 5.0 6.5 8.9 11.4 13.6 15.1 Mass of wet soil (kg) 1.70 1.90 2.00 1.98 1.95 1.92

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