Now a days Thermo-Mechanically Treated (TMT) bars are used on reinforced concrete. Before Placing or Buying we must check the quality of reinforcement there are some examination should be done before selecting steel bar for a construction site.
Examine:
1) Weight Per Running Meter
2 Bend Test
3) Re-bend Test
1) Weight Per Running Meter
– Collect a 3-sample bundle rod.
– Cut a sample of 1 meter length from each bundle.
– Weigh these sample rods and record on a note.
– Now, calculate the theoretical weight of the rod, which is given by
W= (DxD)/162.27
Where, D= Dia of Rod in mm.
Unit=Kg/m
– Compare sample rod weight and theoretical weight it should be same.
2) Bend Test
– Collect a sample of appropriate length not less than 1m.
– Bend it for first 90, 135 & 180 Degree.
Check for crack at bent section. If crack occur than it get failed. Crack should not occur at 180 degree.
3) Re-Bend-Test
– After bend test we can re bend the same sample that is used for the bend test.
– Again repeat same process for re bend that is 180, 135 & 90 degrees.
Check for crack at bent section. If crack occur than it get failed. Crack should not occur at 90 degree