Expert: Babak Esmailzadeh Hakimi - 1/6/2012

Question
Hello Sir,
can you please explain me about Shear Enhancement. actually this situation occurs at column is not continuing from ground floor slab to next level slabs. that should be sway. please tell me how to calculate shear Enhancement.
Thank you,
Sirisha

Answer
Dear Sirisha

Shear enhancement is not a very popular expression to explain about the critical shear stress in beams and girders near supports or in the case of shear stress concentration in the case of discontinuities in columns vertical alignment and so on. In most cases shear enhancement is prone to threaten the ductile and plastic deformabily of structure, providing it with great hazard of sudden failure specially in the case of abnormal loading , like earthquake loading. Then don't be afraid because there is no formulated methods to find a shear enhancement, but you should examine your structural analysis to find shear concentrations. You should  avoid  shear concentrations and provide your members with good shear strength. A general suggestion is to avoid shear enhancement rather than to confront it.

Please don't hesitate to ask me further.

Regards
Babak E Hakimi