shear check for plate elements

[silephbur]

where should i compare the values of SQx and SQy? is it only for fv = Vc/bwd?

what if concrete shear capacity is not enough? what can i do?

how can i design link bars to increase shear capacity?

 

[MotorCity]

Not sure what SQx or SQy is, but to increase the shear capacity you can increase the dimensions, increase the concrete strength, add stirrups, reduce stirrup spacing, etc. (Since this is a plate element, you may not be able to add stirrups depending on the thickness of your plate, but it is a method nonetheless)

 

[DaveAtkins]

I use RISA-3D, which uses the terms Qx and Qy.

Be careful how you interpret results. You may get a very high shear at a very isolated location, but, in my opinion, that does not mean the concrete will fail in shear. I occasionally do some averaging of shear results to get a more realistic shear value.

DaveAtkins

 

[WARose]

I use SQx & SQy (as a STAAD user). I normally compare these values to the allowable (i.e. Φ*2*f'c^1/2 for one-way stresses).

Keep in mind though: you will need to (either) factor up the stresses or factor down the allowable to account for the fact that you are getting stresses based on the full thickness of the element. In actuality, the stress will be higher based on the fact the thickness that resists the shear stress will actually be the depth to re-bar ("d") rather than the full thickness.

 

[silephbur]

im sorry. it's not Vc/bwd but Fv = (phi)(0.17)(lambda)sqrt(f'c) rather (in SI units).

@DaveAtkins is averaging shear values an acceptable method? is there any provision from any code that allows us to get the average shear for our design? if yes, then i think it will help me on my current design project that only fails in shear when compared to Fv.