Table for Development Length for Deformed Bars in Tension/Compression
A development length belongs to the amount of rebar length that is necessary for being implanted or projected into concrete to develop a required bond strength among the two materials as well as develop necessary stress in steel at that section.
When there is no need for the reinforcement bar to bear the tensile forces that means tension at that section is about zero, then it becomes essential to create the bar further in order that the grip or bond among the steel and concrete produce a continuous structure.
If there is no development length, then the restraining force in concrete section becomes relatively feeble as well as ineffective to retain the position of highly stressed bars which lead to splitting of bars from concrete.
Consequently, development length is arranged to provide a fixed support to the bars. In some situations, where no space exists or very little space is present for extra length, hooks are useful for restraint.
Given below, an extensive table for Development Length of Bars as stated by IS 456: 2000 (Working Stress Method).
The provided values are computed as indicated by cl. 26.2.1 of IS 456: 2000.
Stress in steel bars considered is 230 N/mm2.