To Determine Bend Test on Steel Bar
Apparatus:
UTM, test specimen, bending table support pin.
Procedure:
-
Take a test specimen of the steel rod.
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Measure the diameter of the steel rod. Take at least 3 readings and calculate the mean.
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Now place the test specimen in the bending table specimen should be kept in the bending table in such a way that the plane
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Intersecting the longitudinal ribs is parallel to the axis of the pin.
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Select suitable rang of scale.
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Start the machine and start applying load continuously and uniformly throughout the bending.
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As the load is applied on the rod it will start bending.
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Discontinue the application of load when the angle of bent specified in the material specimen has been achieved before rebound.
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Take out the specimen and examine the tension surface of the specimen for cracking.
Specification for Angel in Bend Test:
Bar # 3 to Bar #11 should bend up to 180o without crack
Bar # 14 & Bar # 18 should bend upto90o without crack
This all specification has been given in AASHTO (American Association for Sate Highway and Transportation Officials)
Bend Test Requirements:
|
Bar No |
Grade 40 |
Grade 60 |
Grad 75 |
|
3, 4, 5 |
3 ½ db |
3 ½ db |
------------------- |
|
6 |
5 db |
5 db |
------------------- |
|
7, 8 |
------------------- |
5 db |
------------------- |
|
9, 10 |
------------------- |
7 db |
------------------- |
|
11 |
------------------- |
7 db |
7 db |
|
14, 18 |
------------------- |
9 db |
9 db |
