SM Lab Manual_NIT Trichy (1)

8/11/2019 SM Lab Manual_NIT Trichy (1)

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STRENGTH OF MATERIALS

LABORATORY

MANUAL

(July 2014-2015)

(IIIrdSemester)

Department of Civil Engineering

NIT Trichy


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LIST OF EXPERIMENTS

SL.NO NAME OF THE EXPERIMENT

1.

A). STANDARD CONSISTENCY TEST ON CEMENT

B). INITIAL SETTING TIME FOR CEMENT

C). SPECIFIC GRAVITY OF CEMENT

2.DEFLECTION OF A SIMPLY SUPPORTED BEAM (STEEL

AND WOOD)

3.A). IMPACT TEST ON AGGREGATE

B). CRUSHING STRENGTH OF AGGREGATE

4.A). TEST ON CLOSED COIL SPRING

B). TEST ON OPEN COIL SPRING

5. TENSION TEST

6.A). TORSION TEST

B). HARDNESS TEST

7.A). COMPRESSIVE STRENGTH OF BRICK

B). COMPRESSIVE STRENGTH OF CONCRETE BLOCKS


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STANDARD CONSISTENCY TEST

Exp No:1a

Date:

Aim:

To determine the consistency of given cement.

Apparatus requi red:

1. Vicat apparatus with standard plunger2. Vicat Mould3. Flat plate

Procedure:

300 Gram of cement was weighed accurately. 24% of water by weight of cement was mixed thoroughly with cement to form a thin paste.

The cement paste was taken in a vicat mould.

The top surface of cement paste was leveled.

The vicat mould with cement paste was placed below the vicat apparatus placed provided with a

plunger.

The plunger was lowered near the surface of the mould and then released.

The reading in the vicat apparatus was noted.

The test was continued in steps of 2% till the depth of penetration is between 5 to 7 mm from the

bottom of the mould.

The corresponding water content was noted as the standard consistency of cement.

Observat ion:

Weight of cement taken = 300 g

Trial Water content by weight of cement (%) Depth of penetration (mm)

1

2

3

Result:

The standard consistency of cement was found to be =


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INITIAL SETTING TIME TEST

Exp No:1b

Date:

A im:

To determine the initial setting time of cement.

Apparatus:

1. Vicat apparatus with standard plunger2. Vicat mould3. Flat Plate

Observat ions:


Volume of water added =0.85 P (ml)

Procedure:

300 Gram of cement was weighed accurately and mixed with 0.85 the water required forconsistency.

The cement paste was mixed thoroughly with water so as to form a thin paste.

The cement paste was taken in a vicat mould.

The top surface of cement paste was leveled.

The vicat mould with cement paste was placed below the vicat apparatus placed provided with aVicat needle,

The needle was lowered and then released immediately and the corresponding was noted.

The above procedure was repeated for different time intervals and the readings were noted.

The time interval between mixing and time at which the needle penetrates the test block to adepth of 5-7 mm from the bottom was noted as the initial setting time.

Observat ion:

Weight of cement taken =

Sr. No Time from the period of mixing (min) Vicat Apparatus (mm)

1

2

3

4

5

6

7

8

9

10

Result:

The initial setting time for cement was found to be =_____________________(min)


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SPECIFIC GRAVITY OF CEMENT

Exp No:1c

Date:

Aim: To determine the specific gravity of cement using Le Charelier Flask or Specific GravityBottle.

Apparatus:

1. Le Charelier Flask or Specific Gravity Bottle2. Balance capable of weighing 0.1gm.

Observat ions:


Volume of water added =0.85 P (ml)

Procedure:

Weigh a clean and dry Le Chatelier Flask or Specific Gravity Bottle with its stopper (W1).

Place a sample of cement up to half of the flask (about 50 gm) and weight with its stopper (W2).

Add Kerosene to cement in flask till it is about half full.

Mix thoroughly with glass rod to remove entrapped air.

Continue stirring and add more kerosene till it is flush with the graduated mark.

Dry the outside and weigh (W3).

Entrapped air may be removed by vacuum pump, if available.

Empty the flask, clean it refills with clean kerosene flush with the graduated mark wipe dry the

outside and weigh (W4).

Observat ions

Weight of empty flask, W1 =

Weight of the flask + Cement, W2 =

Weight of the flask + Cement + Kerosene, W3 =

Weight of the flask + Kerosene, W4 =

Specific gravity of kerosene = 0.79

Calculations:

Specific Gravity =

79.0)43()12(

)12(

WWWW

WW=

Result:

Specific Gravity of Cement =


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DEFLECTION OF SIMPLY SUPPORTED BEAM

Exp No: 2

Date:

A im:

To conduct a deflection test on a simply supported beam and to find modulus of elasticity and flexural

rigidity.

Apparatus:

1. Loading Bar

2. Meter Scale

3. Vernier Scale

4. Deflectometer

Formula:

Youngs Modulus (E) =I

Wl

76811

3

N/mm2

Flexural Rigidity (K) = E I N/mm2

W=Load (N)

l= Length of beam (mm)

= deflection (mm)

I = moment of inertia (mm4

)

Procedure:

Length, breadth and thickness of the beam has been measured using metric scale.

Deflectometer has been arranged at the bottom of the beam at one fourth the length of thesupport.

Load has been applied at the center of the beam with weights of 0.5, 1, 25 kg.

Readings of the deflection has been taken from the deflectometer and tabulated.

Youngs Modulus has been calculated for each of the reading and average was found.

Graph was drawn with deflection on X-axis and load on Y-axis.

From graph (w/ ) was noted and Youngs Modulus and Flexural rigidity has been noted down.

Observation s: (STEEL)

Length of beam (l) = mm

Breadth of beam (b) = mm

Thickness of beam (t) = mm

Least count = mm


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Sl.no

Load(W) (kg)

Deflectometer Readings Deflection(mm)

Youngs modulus

(N/mm2

)Loading Unloading Mean

1.

2.

3.

4.

5.

6.

7.

8.

9.

Model Calculations :

I =12

3bt=

Youngs Modulus (E) =

W

I

l

768

11 3=

Flexural Rigidity (K) = E I =

Graph:

A graph is plotted between load and deflection with Load on Y-axis and deflection on X-axis.

Slope

Whas been calculated from the graph.

W=

E =

I

Wl

768

11 3=

Observation s: (WOOD)

Length of beam (l) = mm

Breadth of beam (b) = mm

Thickness of beam (t) = mm

Least count = mm


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Sl.no

Load(W) (kg)

Deflectometer Readings Deflection(mm)

Youngs modulus

(N/mm2

)Loading Unloading Mean

1.

2.

3.

4.

5.

6.

7.

8.

9.

Model Calculations :

I =12

3bt=

Youngs Modulus (E) =

W

I

l

768

11 3=

Flexural Rigidity (K) = E I =

Graph:

A graph is plotted between load and deflection with Load on Y-axis and deflection on X-axis.

Slope

Whas been calculated from the graph.

W=

E =

I

Wl

768

11 3=

Result:

For Steel

(i) Modulus of elasticity EAnalytically =

Graphically =

(ii) Flexural rigidity KAnalytically =

Graphically =


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For Wood

(i) Modulus of elasticity EAnalytically =

Graphically =

(ii) Flexural rigidity KAnalytically =

Graphically =


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IMPACT TEST ON AGGREGATE

EX. NO. 3aDATE:

AIM:

To find the Impact value for the given sample of aggregate.

APPARATUS REQUIRED:

1. IS Sieve (12.5 mm, 10 mm, 2.36 mm)

2. Tamping rod

3. Test sample

4. Hammer of weight 14 kg.

FORMULA:

Impact value = (W2/ W1) x 100

where,

W1= Weight of the dry sample in g

W2= Weight of fraction passing through IS 2.36 mm sieve in g.

PROCEDURE:

Aggregate passing through IS 12.5 mm sieve and retained in IS 10 mm sieve was taken as the

sample.

The test sample was filled in a mould in 3 layers by giving 25 blows for each.

layer using tamping rod and leveled.

The dry weight of the sample was noted as W1.

The whole sample was filled in a cylindrical steel cup.

The hammer was allowed to fall freely from a height of 38 cm on the aggregate.

The sample was subjected to 15 blows and it was sieved using IS 2.36 mm sieve.

The fraction passing through sieve was weighed and noted as W2.

The impact of the aggregates was calculated using the formula (W2/ W1) x 100.

OBSERVATION:

Empty weight of the mould =

Empty weight of the mould + aggregate a) =

b) =

Weight of dry sample, W1 a) =

b) =


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S.No. Weight of the dry

sample, W1

Weight of fraction

passing through IS

2.36 mm sieve,

W2

Impact value

(W2/W1) x 100

Unit g g %

1.

2.

MODEL CALCULATIONS:

Weight of the dry sample, W1=

Weight of fraction passing through IS 2.36 mm sieve, W2

=

Aggregate Impact value (W2

/ W1) x 100 =

Average Impact value =

RESULT:

The impact value of the given aggregate is = __________.


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CRUSHING TEST ON AGGREGATE

EX. NO. 3b

DATE:

AIM:

To find the crushing strength value for the given sample of aggregate.

APPARATUS REQUIRED:

1. IS Sieve (12.5mm, 10mm, 2.36mm).

2. Tamping rod.

3. Test sample.

4. Hammer of weight 40 tons.

FORMULA:

Crushing Strength = () Where,

W1= Weight of dry sample in g.

W2 = Weight of fraction passing through IS 2.36mm sieve in g.

PROCEDURE:

Aggregate passing through IS 12.5mm sieve and retained in IS 10mm sieve was taken as the

sample.

The test sample was filled in a mould in 3 layers by giving 25 blows for each layer using tamping

rod and leveled.

The dry weight of the sample was noted as W1.

The sample was transferred to a cylinder with base plate and was carefully leveled.

The plunger was inserted horizontally on the surface.

The apparatus was placed in the UTM and a total load of 40 tons was applied.

The fraction passing through IS 2.36 sieve was weighed and noted as W2.

The crushing strength value was calculated using the formula () .

OBSERVATION:

Empty weight of the mould =

Empty weight of the mould + aggregate =

Weight of dry sample,W1=

Weight of fraction retained on IS 2.36mm sieve =


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Weight of fraction passing through IS 2.36mm sieve,W2=

S.No. Weight of the dry

sample,W1

Weight of fraction

passing through

IS 2.36mm sieve,

W2

Crushing Strength

()

Unit g G %

1.

MODEL CALCULATIONS:

Weight of dry sample,W1=

Weight of fraction passing through IS 2.36mm sieve,W2=

Crushing Strength = () =

RESULT:

The crushing strength of the given aggregate is = __________.


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TEST ON CLOSED COIL SPRING

Exp No: 4a

Date:

A im:To conduct test on the given spring and to determine the rigidity modulus and spring constant.

Apparatus Requi red:

1. Spring testing machine

2. Meter Scale

3. Vernier Calipers

Formula:

Modulus of rigidity =

4

38

d

nWD

Where

W = average load (kg)

N = number of turns

= deflection (mm)

D = average diameter

d = diameter of coil

p = pitch (mm)

Procedure:

The length of spring, the inner and outer diameter was noted.

The spring is placed in the correct position.

The least count of the dial gauge is noted.

Load is applied and the deflection of the spring was noted down for every 10 kg.

The deflection is measured from the scale attached to the machine and the same procedure isrepeated for each unloading.

The spring constant and modulus of rigidity are calculated analytically.

Graph:

The graph is plotted between load and deflection. Load is along Y-Axis and deflection along X-

Axis.

Observat ions:

Number of turns (n) =

Length of spring (L) =

Diameter of coil (d) =

Inner diameter of spring (D1) =

Outer diameter of spring (D2) =

Mean Diameter D =

2

21 DD


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Radius of coil = d/2 =

Pitch = L/n =

Sl.

no

Load (W)

(kg)

Axial Deformation (mm) Spring

Constant (K)

(N/mm)

Modulus of

Rigidity (N)

(N/mm2

)Loading Unloading Average

1.

2.

3.

4.

5.

6.

Model Calculations:

Modulus of Rigidity =

4

38

d

nWD

From Graph:

K =

W=

N =

W

d

ND4

38=

Result:

(i) Spring Constant (k)

a) Analytically =b) Graphically =

(ii) Modulus of Rigidity (N)



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TEST ON OPEN COIL SPRING

Exp No:4b

Date:

A im: To conduct test on given open coil spring and to determine rigidity modulus and spring constant.


1) Spring Testing Machine.2) Meter Scale.3) Vernier Calipers.

Formula:


E

n

d

nWD

22

4

3sin2

coscos

8

Where, W = Average Load (in kg)

n= Number of turns

= Deflection (in mm)

D = Average Diameter (in mm)

d = Diameter of coil (in mm)

N = Rigidity modulus (N/mm2

)

tan 1

R

p

2

p = Pitch (in mm)

R = Radius of spring (in mm)

Procedure:

The lengths of spring, the outer and inner diameters are noted.

The spring is placed in the correct position.

The least count of the dial gauge is noted.

Load is applied and the deflection of spring was noted for every 10 kg.

The deflection is measured from the scale attached to the machine and the sameprocedure is repeated for each unloading.

The spring constant and rigidity modulus were calculated analytically.

Observat ion:

Number of turns(n) =

Length of spring (L) =


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Diameter of coil (d) =

Inner diameter of spring (D1 ) =

Outer diameter of spring (D2 ) =

Mean diameter D =2

21 DD =

Radius of Coil = d/2 =

Pitch = L/n =

Sl.

no

Load (W)

(kg)

Axial Deformation (mm) Spring

Constant (K)

(N/mm)

Modulus of

Rigidity (N)

(N/mm2

)

Loading Unloading Average

1.

2.

3.

4.

5.

6.

7.

8.

9.

Graph:

A graph was plotted between load and deflection with Load along Y-axis and deflection along X-axis.


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Model Calculation:


E

n

d

nWD

22

4

3 sin2cos

cos

8=

From graph:

K =

W=

N =

E

n

d

nWD

22

4

3 sin2cos

cos

8

Result:

(i) Spring Constant (k)


(ii) Modulus of rigidity (N)a) Analytically =b) Graphically =


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7. Percentage Reduction in Area = 100)'(

2

22

d

dd

Where

d = Final diameter of the rod (mm )

d = Initial diameter of the rod (mm )

Procedure:

The given rod was weighed and its length was measured. The average diameter,d was

determined using the density of the specimen.

The center point of the rod was marked using the punch and marks were made on either side of

the center mark at a distance of 5d.

The given rod was then fixed in the tension grips pf the UTM such that the top and bottom marks

already made, coincides exactly with the top and bottom of the wedge grips respectively. The

extensometer was fixed firmly to the specimen so that its axis coincides with that of the specimen.

The zero error in the extensometer and the testing machine are eliminated.

Extensometer readings are taken for different increment in loads which were applied within theelastic limits.

Load was applied until yield point was reached. The extensometer was then removed and the

ultimate load and the breaking load were noted.

The final diameter, d of the rod was measured at the neck of the ruptured section. The broken

parts were fixed together and the final length , l was measured between the previously marked

punch marks.

Graph:

The following graphs were drawn

1. Load vs ElongationElongation is taken along the X-axis and Load is taken along the Y-axis

2. Stress vs StrainStrain is taken along the X-axis and Stress is taken along the Y-axis

Observat ion:

1. Weight of the rod (W) =

2. Length of the rod (L) =

3. Density of the rod ( ) =

4. Area of cross section of the rod (A) =

5. Diameter of the rod (d) =

6. Gauge Length =


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7. Final Length =

8. Final Diameter (d) =

9. Breaking Load =

10. Ultimate Load =

11. Extensometer gauge Length =

12. Least count of Extensometer =

S.

No

Load

(tons)

Extensometer Reading (mm) Average

Extension

X LC

(mm)

Stress

(N/mm2

)

Strain

X 10 4

Youngs

Modulus

X 105

(N/mm2

)

Left Right Average

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.


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Model Calculation:

1. Area of the specimen, A =l

W

=

2. Diameter of the specimen, d = /4A =

3. Percentage elongation =

l

ll 100)'(

4. Percentage Reduction in Area = 100)'(

2

22

d

dd

5. Ultimate Stress (N/mm2

) = Ultimate load / Area of Cross Section

6. Nominal Breaking Stress (N/mm2

) = Breaking Load / Area of Cross Section

7. Actual Breaking Stress (N/mm2

) = Breaking Load/Final Area of cross section

8. Load =

9. Average Extensometer reading =

10. Stress, =Area

Load

11. Strain, = Average extension / Gauge Length

12. Youngs Modulus, E =

=

13. Proof Stress ( From Graph ) =

Result:

1. Youngs Modulus (E) =

2. Ultimate Tensile Stress (u

) =

3. Nominal Breaking Stress =

4. Actual Breaking Stress =

5. Percentage of Elongation =

6. Percentage of Reduction in Area =

7. Proof Stress =


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TORSION TEST

Exp No:6a

Date:

A im: To find the modulus of rigidity (N) and shear stress of the given shaft.

Apparatus:

1) Torsion testing machine2) Specimen (shaft)3) Vernier calipers

Formula:

J

T =

r

Fs

=L

C

Where,

T = Torque in kg-mm

J = Polar Moment of Inertia in mm4

Fs

= Shear Stress in N/mm2

r = Radius of specimen in mm

L = Length of specimen in mm

= Angle of twist in radians

Procedure:

The specimen was placed in the machine at a proper position.

The torsion dial gauge was set to zero.

The machine was operated manually.

The handle connected to the spindle that holds the specimen was rotated in the clockwisedirection for a twist of angle 5 and the appropriate corresponding torque was recorded.

This was repeated for a twist of angle 10 and 15.

The entire procedure was repeated for 5, 10, 15 in the anti-clockwise direction

The modulus of rigidity was calculated using the formula

Graph was drawn for Angle of Twist Vs Torque and the graphical result was obtained

It was taken care that the twist doesnt exceed the maximum limit.

Graph:

A graph is plotted between Angle of Twist and Torque .Angle of Twist is taken along the Y axis and

Torque is taken along X axis

Observat ion:

Diameter of the specimen (d) =

Length of the specimen (L) =


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Polar Moment of Inertia (J) =

Sl.

No

Clockwise Anti-Clockwise Mean

Torque

(kg-mm)

Modulus

of

Rigidity

(N/mm2

)

Shear

Stress

(N/mm2

)

Angle of Twist Torsion

(kg-

mm)

Angle of Twist Torsion

(kg-

mm)

Degree Radian Degree Radian

Model Calculations:

(T*r)/J = Fs

Result:

(i) The modulus of rigidity of the give shaft (N) analytically = N/mm2

(ii) The modulus of rigidity of the give shaft (N) graphically = N/mm2


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HARDNESS TEST

Exp No: 6b

Date:

A im: To determine the Brinells hardness, Rockwells hardness and number for the given specimen.

Apparatus Requi red:

1. Mild steel specimen.

2. Aluminium specimen.

3. Scheleroscope.

Procedure:

The surface of the test specimen was polished with smooth emery sheet.

The specimen to be tested was placed in proper position and clamped.

The loading screw was fully rotated and then released.

The dial gauge reading was noted corresponding to Brinell, Rockwell and shores.

Hardness number.

The experiment was repeated for other Specimens.

Observat ions:

Sl.

No

Material Trial No. Brinells

Hardness

Number

Rockwells

Hardness

Number

Shores

Hardness

Number

1. Mild Steel

1

2

3

2. Aluminium

1

2

3


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Result:

Mild steel specimen:

1. Brinells hardness no. =

2. Rockwells hardness no. =

3. Shores hardness no. =

Aluminium specimen:

1. Brinells hardness no. =

2. Rockwells hardness no. =

3. Shores hardness no. =


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COMPRESSIVE STRENGTH OF BRICK

Exp No:7a

Date:

A im:

To determine the compressive strength of Brick.

To find the percentage of water absorbed by the Bricks.


1. Bricks2. Weighing Machine3. Compression testing machine4. Metric scale

Formula:

1. Compressive Strength = Crushing Load /Area (N/mm2

)

2. Percentage water absorbed = 100

1

12

WWW

Where,

W1 = Weight of Brick before soaking in water

W2 = Weight of brick after soaking in water

Procedure:

Three different Brick blocks were taken and were weighed(W1), then the bricks were soaked inwater for 30 minutes following which the bricks were weighed again.(W2)

The brick blocks were kept in the compression testing machine and the reading corresponding tothe maximum load was noted.

Observat ion:

S.No Brick Dimension W1

(g)

W2

(g)

% Water

Absorbed

Crushing

Load (kN)

Compressive

Strength (N/mm2

)L B H

1.

2.

3.


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27

Model Calculation:

Weight of Brick before soaking in water, W1 =

Weight of brick after soaking in water, W2 =

Percentage absorbed = 100

1

12

WWW

=

Compressive Strength = Crushing Load /Area =

Result:

Percentage water absorbed by:

1. Brick A =2. Brick B =3. Brick C =

The compressive strength of

1. Brick A =2. Brick B =3. Brick C =


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COMPRESSIVE STRENGTH OF CONCRETE BLOCK

Exp No:7b

Date:

Aim:

To determine the compressive strength of the given concrete cube


Concrete Cube

1) Compression Testing Machine2) Metric Scale

Formula:

Compressive strength = Crushing load/Area (N/mm2)

Procedure:

Three different concrete cubes are taken; using the metric scale the length of the sides wasmeasured.

The concrete cube was kept on the Compression Testing Machine and the readingcorresponding to the maximum load was noted.

Observation Table:

S.No Cube Dimension Area (mm2)

A

% Water

Absorbed

Crushing Load

(kN)

Compressive

Strength (N/mm2)

L B H

1.

2.

3.


30/30

Model Calculation:

Compressive strength = Crushing Load / Area =

Result:

The compressive strength of :

Cube A =

Cube B =

Cube C =

Documents

SM Lab Manual_NIT Trichy (1)