PRC-I LAB MANUAL PDF

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LABORATORY MANUAL REINFORCED CONCRETE-I SUBMITTED BY: _______________________ ______________________ SUBMITTED TO: ______________________ DEPARTMENT OF CIVIL ENGINEERING THE UNIVERSITY OF LAHORE (ISLAMABAD CAMPUS) UOL/BSCE-15 1 PLAIN & REINFORCED CONCRETE-I EXPERIMENTS INDEX Name: --------------...

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LABORATORY MANUAL REINFORCED CONCRETE-I

SUBMITTED BY: _______________________

______________________

SUBMITTED TO: ______________________

DEPARTMENT OF CIVIL ENGINEERING THE UNIVERSITY OF LAHORE (ISLAMABAD CAMPUS)

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PLAIN & REINFORCED CONCRETE-I EXPERIMENTS INDEX

Name: -------------------Sr. Name Of Experiments No.

Date Marks Signature

01 02 03 04 05 06 07 08

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Reg. # ----------

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Sr. No.

LIST OF EXPERIMENTS

Page No.

01

Layout Of Reinforced Concrete Laboratory

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02

Compressive Strength Of Cylindrical Concrete Specimen.

5

03

Compressive Strength Of Concrete Cubes.

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04

Splitting Tensile Strength Of Cylindrical Concrete Specimen.

13

05

Flexural Strength Of Concrete (Using Simple Beam With Third Point Loading).

17

06

Flexural Strength Of Concrete (Using Simple Beam With MidPoint Loading).

20

07

To Perform SCHMIDT Rebound Hammer Test On A Specified Member To Find Out The Compressive Strength Of Concrete.

23

08

To Perform The Ultrasonic Pulse Velocity Test (UPV) On A Specified Concrete Member To Find Out Compressive Strength.

27

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EXPERIMENT No. 01 LAYOUT OF REINFORCED CONCRETE LABORATORY.

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EXPERIMENT. No. 02 COMPRESSIVE STRENGTH OF CYLIDRICAL CONCRETE SPECIMEN. 2.1 Designation. ASTM C39/39M-03

2.2 Scope This test method covers the determination of compressive strength of cylindrical concrete specimens. Values obtained will depend on the size and shape of the specimen, batching, mixing procedures, the methods of sampling, molding and fabrication and the age, temperature, and moisture conditions during curing of concrete specimens.

2.3 Apparatus Cylinder Molds, Concrete Mixer, Trowel, Weighing Balance, Tamping Rod (Circular), Water Tank, Compression Testing Machine (UTM) Etc.

2.4 Materials Coarse Aggregates, Fine Aggregates, Cement, Water, Oil or Grease.

2.5 Mix Ratio 1:2:4

2.6

Water/cement ratio Select suitable water/cement ratio.

W/C ratio = 2.7

Procedure 1. Size of cylindrical concrete specimen is 6in.x12in (150mmx300mm). 2. Calculate the amount of material required for 6 cylinders (Two Cylinders for each testing age, i.e. for 7, 14, 28 days) according to Volume and density for mix ratio 1:2:4 and weigh them. Volume of Cylinder = 3.14*(R2)*L =………………. Where, R is radius of cylinder. L is length of cylinder. Density of plain concrete

=………………….

Weight of wet material for 01 cylinder

=………………….

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Weight of dry material for 01 cylinder

=………………….

Weight of dry material for 06 cylinder

=………………….

Table 2.1: Calculated Materials Concrete Test Method Mix Cement(kg) Ratio ASTM C39/C39M03 (06 cylinders) W/C =

-

Fine Agg. (kg)

Coarse Agg. (kg)

Water (lits.)

-

-

-

-

1:2:4

3. Mix all the calculated amount of material for 06 cylinders together. In concrete mixer. Buttering of concrete mixer must be done before mixing. 4. Pour out the concrete in the container. 5. Oil the cylinder molds so that remolding should be easy. 6. Fill the molds in three equal layers, each layer being given 25 Strokes of a tamping rod. 7. Level the surface to give smooth finish. 8. Allow the cylinders to set for 24 hours and then disassemble the molds. Submerge the cylinders in the water tank for curing purpose for 3, 7, 28 days. 9. Concrete cylinders must be capped or capping pads should be used for testing so that application of load must be uniform throughout the area of cylinder.

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10. After 7, 14, 28 days of casting of cylinders, test the cylinder samples in the compression testing machine (UTM) in which the load must be applied at a rate of approximately 0.25 (N/mm2/s). The failure surfaces may be of the following shapes.

11. Note down the readings for each concrete sample and fill the Table 2.2 given in calculation section. 12. For testing of concrete specimens following are the permissible tolerance limits. Test Age Permissible Tolerance 3 Days 7 Days 28 Days

2h or 2.8 % 6h or 3.6 % 20h or 3.0 %

2.8 Calculation Calculate the compressive strength of the specimen by dividing the maximum load carried by the specimen during the test by the average cross-section area determined to the nearest 10 psi. Complete the table for all 6 samples for each specimen and be careful about the age of specimen. If the specimen length to diameter ratio is 1.75 or less, correct the result obtained in 2.8 by multiplying by the appropriate correction factor in the following table. L/D

1.75

1.50

1.25

1.00

Factor

0.98

0.96

0.93

0.87

Use interpolation to determine correction factor for L/D values between those given in the table.

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Calculation for Cylindrical Specimens: Sr. #

Group ID

W/C

Casting Date

Testing Date

Age (days)

Lo (kN)

Strength (psi)

01 02 03 04 05 06

2.9 Precautions. 1. Material should be properly mixed in mixer so that actual strength should be achieved. 2. Concrete cylinder must be properly compacted. 3. Label the concrete cylinder with casting date and group ID. 4. Compression tests of moisture-cured specimens shall be made as soon as possible after removal from moist storage. 5. Permissible tolerance limits of age of concrete specimens must be followed for testing. 6. Prior to testing the specimen, verify that the load indicator is set to zero. 7. Apply the load continuously and without shock. 8. Prior to testing , neither end of test specimen shall depart from perpendicularity to the axis by more than 0.50.

2.10 Remarks:

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EXPERIMENT.No. 03 COMPRESSIVE STRENGTH OF CONCRETE CUBE SPECIMEN. 3.1 Designation. BS 4550-3.4:1978 3.2 Scope This test method covers the determination of compressive strength of cubical concrete specimens. Values obtained will depend on the size and shape of the specimen, batching, mixing procedures, the methods of sampling, molding and fabrication and the age, temperature, and moisture conditions during curing of concrete specimens.

3.3 Apparatus Cube Molds, Concrete Mixer, Trowel, Weighing Balance, Tamping Rod (Rectangular), Water Tank, Compression Testing Machine etc.

3.4 Materials Coarse Aggregates, Fine Aggregates, Cement, Water, Oil or Grease.

3.5 Mix Ratio 1:2:4

3.6 Water/cement ratio Select suitable water to cement ratio.

W/C ratio 3.7

=

Procedure 1. Size of cubical concrete specimen is 6in.x6in.x6in (150mmx150mmx150mm). 2. Calculate the amount of material required for 6 cubes (2 Cubical Samples for each testing age i.e. for 7, 14, 28 days) according to Volume and density for mix ratio 1:2:4 and weight them. 216in2

Volume of Cube

=

Density of plain Concrete

=………………….

Weight of wet material for 01 Cube

=………………….

Weight of dry material for 01 Cube

=………………….

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=………………….

Weight of dry material for 06 Cube

Table 3.1: Calculated Materials Conc. Mix Ratio

Cement

Fine Aggregates

Coarse Aggregates

Water

ASTM 4550-3.4:1978 (06 cubes)

-

-

-

-

-

W/C =

1:2:4

Test Method

3. Mix all the calculated amount of material for 06 cubes together. In concrete mixer. Buttering of concrete mixer must be done before mixing. 4. Pour out the concrete in the container. 5. Oil the cube molds so that remolding should be easy. 6. Fill the molds in three equal layers, each layer being given 35 Strokes of a tamping rod. 7. Level the surface to give smooth finish. 8. Allow the cubes to set for 24 hours and then disassemble the molds. Submerge the cubes in the water tank for curing purpose for 3, 7, 28 days. 9. Concrete cubes must be capped or capping pads should be used for testing so that application of load must be uniform throughout the area of cylinder.

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10. After 7, 14, 28 days of casting of cylinders, test the cube samples in the compression testing machine in which the load must be applied at a rate of approximately 0.25 (N/mm2 .s).

11. Note down the readings for each concrete sample and fill the Table 2.2 given in calculation section. 12. For testing of concrete specimens following are the permissible tolerance limits. Test Age

Permissible Tolerance

3 Days 7 Days 28 Days

2h or 2.8 % 6h or 3.6 % 20h or 3.0 %

Table-3.2: Temperature and humidity conditions. Permitted temperature variation (Co)

Minimum relative humidity (%)

Mixing room

+2

50

Moist curing chamber

+1

90

Water curing tank

+1

-

Compression testing room

+2

50

Situation

3.8 Calculation Calculate the compressive strength of the specimen by dividing the maximum load carried by the specimen during the test by the average cross-section area determined to the nearest 10 psi. Complete the table for all 6 samples for each specimen and be careful about the age of specimen.

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Calculation for Cubical Specimens: Sr. # Group ID

W/C

Casting Date

Testing Date

Age (days)

Load (kN)

Strength (psi)

01 02 03 04 05 06

3.9 Precautions. 1. Material should be properly mixed in mixer so that actual strength should be achieved. 2. Concrete cube must be properly compacted. 3. Label the concrete cube with casting date and group ID. 4. Compression tests of moisture-cured specimens shall be made as soon as possible after removal from moist storage. 5. Permissible tolerance limits of age of concrete specimens must be followed for testing. 6. Prior to testing the specimen, verify that the load indicator is set to zero. 7. Apply the load continuously and without shock. .

3.10 Remarks

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EXPERIMENT. No. 04 SPLITTING TENSILE STRENGTH OF CYLINDRICAL CONCRETE SPECIMENS. 4.1 Designation. ASTM C496/C496M-04 4.2 Scope This test method covers the determination of the splitting tensile strength of cylindrical concrete specimens, such as molded cylinders and drilled core.

4.3 Significance and Use Splitting tensile strength is simpler to determine than direct tensile strength. Splitting tensile strength is used to evaluate the shear resistance provided by concrete in reinforced lightweight aggregate concrete members

4.4 Apparatus Cylindrical Molds, Concrete Mixer, Trowel, Weighing Balance, Tamping Rod (Cylindrical), Water Tank, Compression Testing Machine etc.

4.5 Materials Coarse Aggregates, Fine Aggregates, Cement, Water, Oil or Grease.

4.6 Procedure 1. Draw diametric lines on each end of the specimen using a suitable device that will ensure that they are in the same axial plane (see fig.-1), or as an alternative. Use the aligning jig shown in fig.2.

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2. Determine the diameter of the test specimen to the nearest 0.01 in. [0.25 mm] by

3.

4. 5. 6. 7.

averaging three diameters measured near the ends and the middle of the specimen and lying in the plane containing the lines marked on the two ends. Determine the length of the specimen to the nearest 0.1 in. [2 mm] by averaging at least two length measurements taken in the plane containing the lines marked on the two ends. Center one of the plywood strips along the center of the lower bearing block. Place the specimen on the plywood strip and align so that the lines marked on the ends of the specimen are vertical and centered over the plywood strip. Place a second plywood strip lengthwise on the cylinder, centered on the lines marked on the ends of the cylinder. Position the assembly to ensure the following conditions:  The supplementary bearing bar or plate, when used, and the center of the specimen are directly beneath the center of thrust of the spherical bearing block.  Position the bearing strips, test cylinder, and supplementary bearing bar by means of the aligning jig as illustrated in Fig. 3 and center the jig so that the supplementary bearing bar and the center of the specimen are directly beneath the center of thrust of the spherical bearing block.

8. Record the maximum applied load indicated by the testing machine at failure. Note the type of failure and the appearance of the concrete. 9. Apply the load continuously and without shock, at a constant rate within the range 100 to 200 psi/min [0.7 to 1.4 MPa/min] splitting tensile stress until failure of the specimen.

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4.7 Calculation Calculate the splitting tensile strength of the specimen as follows.

T = 2P/πld T =…………… Where, T= splitting tensile strength, psi [MPa], P = maximum applied load indicated by the testing machine, lbf [N], l= length, in. [mm], and d= diameter, in. [mm].

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4.8 Precautions 1. Apply the load continuously and without shock. 2. Apply load at a constant rate within the range 100 to 200 psi/min [0.7 to 1.4 MPa/min]. 3. There must be no surface undulations of the test specimen. 4. The curing must be according to standards because it directly affects the strength.

4.9 Remarks:

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EXPERIMENT. No. 05 FLEXURAL STRENGTH OF CONCRETE (USING SIMPLE BEAM WITH THIRD-POINT LOADING). 5.1 Designation. ASTM C78-02 5.2 Scope This test method covers the determination of the flexural strength of concrete by the use of a simple beam with third-point loading.

5.3 Apparatus Loading apparatus, Beam mold , Trowel, Weighing Balance, Mold oil or Grease Flexure Testing Machine etc.

5.4 Materials Coarse Aggregates, Fine Aggregates, Cement, Mold Oil or Grease.

5.5 Procedure 1. Flexural tests of moist-cured specimens shall be made as soon as practical after removal from moist storage. Surface drying of the specimen results in a reduction in the measured flexural strength. 2. When using molded specimens, turn the test specimen on its side with respect to its position as molded and center it on the support blocks. 3. Center the loading system in relation to the applied force. Bring the load-applying blocks in contact with the surface of the specimen at the third points and apply a load of between 3 and 6 % of the estimated ultimate load. 4. Using 0.004 in. (0.10 mm) and 0.015 in. (0.38 mm) leaf-type feeler gages, determine whether any gap between the specimen and the load-applying or support blocks is greater or less than each of the gages over a length of 1 in. (25 mm) or more. 5. Grind, cap, or use leather shims on the specimen contact surface to eliminate any gap in excess of 0.004 in. (0.10 mm) in width. Leather shims shall be of uniform 1⁄4 in. (6.4 mm) thickness, 1 to 2 in. (25 to 50 mm) width, and shall extend across the full width of the specimen. 6. Gaps in excess of 0.015 in. (0.38 mm) shall be eliminated only by capping or grinding. Grinding of lateral surfaces should be minimized inasmuch as grinding may change the physical characteristics of the specimens. 7. Apply the load at a rate that constantly increases the extreme fiber stress between 125 and 175 psi/min (0.86 and 1.21 MPa/min), when calculated in accordance with 8.1, until rupture occurs. The loading rate is calculated using the following equation:

r = Sbd2/L Where,

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r = loading rate, lb./min [MN/min] S = rate of increase in extreme fiber stress, psi/min (MPa/min), b= average width of the specimen, in.(mm), d= average depth of the specimen, in. (mm), and L= span length, in. (mm). To determine the dimensions of the specimen cross section for use in calculating modulus of rupture, take one measurement at each edge and one at the center of the cross section to determine the average width and the average depth.

Fig .5.1 Diagrammatic View of a Suitable Apparatus for Flexure Test of Concrete by Third-Point Loading Method.

5.6 Calculation 1. The fracture initiates in the tension surface within the middle third of the span length, calculate the modulus of rupture as follows:

R = PL/bd2 Where, R = modulus of rupture, psi or MPa.

P = maximum applied load indicated by the testing machine, lb. or N, UOL/BSCE-15

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L = span length, in., or mm b = average width of specimen, in,. or mm, at fracture , and d = average depth of specimen, in., or mm, at the fracture. 2. The fracture occurs in the tension surface outside of the middle third of the span length by not more than 5 % of the span length, calculate the modulus of rupture as follows: R= 3Pa/bd2 Where: a = average distance between line of fracture and the nearest support measured on the tension surface of the beam, in., (or mm).

5.7 Precautions 1. Surface drying of the specimen results in the measured flexural strength. 2. Load the specimen continuously and without shock. 3. If the fracture occurs in the tension surface outside of the middle third of the span length by more than 5% of the span length , discard the results of test.

5.8 Remarks:

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EXPERIMENT.No. 06 FLEXURAL STRENGTH OF CONCRETE (USING SIMPLE BEAM WITH CENTRE-POINT LOADING). 6.1 Designation. ASTM C293-02 6.2 Scope This test method covers the determination of the flexural strength of concrete by the use of a simple beam with third-point loading.

6.3 Apparatus Loading apparatus, Beam Mold , Trowel, Weighing Balance, Mold oil or Grease Flexure Testing Machine etc.

6.4 Materials Coarse Aggregates, Fine Aggregates, Cement, Mold Oil or Grease.

6.5 Procedure 1. Flexural tests of moist-cured specimens shall be made as soon as practical after removal from moist storage. Surface drying of the specimen results in a reduction in the measured flexural strength. 2. When using molded specimens, turn the test specimen on its side with respect to its position as molded and center it on the support blocks. 3. Center the loading system in relation to the applied force. Bring the load-applying blocks in contact with the surface of the specimen at the third points and apply a load of between 3 and 6 % of the estimated ultimate load. 4. Using 0.004 in. (0.10 mm) and 0.015 in. (0.38 mm) leaf-type feeler gages, determine whether any gap between the specimen and the load-applying or support blocks is greater or less than each of the gages over a length of 1 in. (25 mm) or more. 5. Grind, cap, or use leather shims on the specimen contact surface to eliminate any gap in ...