| Applies To | |||
| Product(s): | STAAD Advanced Concrete Design | ||
| Version(s): | Connect Edition | ||
| Environment: | |||
| Area: | Concrete Design | ||
| Subarea: | General | ||
| Original Author: | Ranjana, Bentley Technical Support Group | ||
I noticed that RCDC have calculated the stirrup using Fe415 even if the steel grade chosen for design is Fe500. The longitudinal rebars of course is designed using the specified grade, i.e., Fe500. Is this intentional since IS456 restricts the maximum grade for stirrup at 415N/mm2? Also, is the same true in the case of design for special confining lateral ties since IS code is somewhat silent on this if I’m not mistaken
Answer : For Shear calculations in column, beam, footing the Maximum stress in reinforcement is limited to 415 N/sqmm. Please refer below snap from IS 456,
The shear failure is a sudden failure thus for the shear calculations, IS code have restricted the stress to 415 N/sqmm for higher reinforcement grade.
For calculation of Special confining links, actual reinforcement grade is considered. if Fe-500 is used in the design, the special confining links are calculated based on 500N/sqmm stress. the guidelines are given in IS 13920-2016 for use if higher grade reinforcement. refer below snap from IS 13920-2016
From Version 11 update 3.1 option has been provided to use user defined input for steel grade.