RAM Concept - Program Shear Reinforcement (2-way slab)

Question

I'm modeling/designing a 2-way transfer slab for a concrete podium building in RAM Concept and the program is adding one-way shear reinforcement around the columns. I was reviewing an audit of the cross section and noticed the following: 
 
 ɸVc > Vu 
 The audit reads "No stirrups required" 
 
 Why is the program adding shear reinforcement if the audit indicates they are unnecessary? Is there a setting I can check/update to avoid having the unnecessary shear stirrups added to the slab? 
 Thanks!

Seth Guthrie · Answer

1. My error. I confess to still being more familiar with the older code layout. For two-ways slabs we are following the chapter 8 sections. In the case above the max shear demand was more than phi Vc. 
 
 2. The demand is a result of the finite element analysis. A full width strip would certainly give you a much larger capacity with only a bit larger demand.

Seth Guthrie · Answer

The audit is for a single section there are several envelopes and "design passes" to report, so you might be looking at a pass that is OK, while another requires stirrups, or it might be an adjacent section that controls. This wiki is useful: https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/3094/ram-concept-shear-reinforcement-faq

Seth Guthrie · Answer

Let's consider Second floor, strip 2C. A plot of the shear density is useful to establish which sections require the shear reinforcement. 
 
 Here's the audit for the controlling section on the left. 
 Auditing 2C-3, section 1.html 
 If you are comparing Vu to Vc remember to incorporate phi (0.75) and recognize the requirement of 9.6.3.1 (* only for beams in ACI 318-14 *): 
 
 In this specific case, the phiVc limit is exceeded, so minimum shear reinforcement is required. At the next section it is OK and the next section is 1.45' away which is approximately "d", so I think you would be justified in ignoring this bar set. Adjusting the strip support width is another way to account for this, but since "d" is a moving target and since the sections are also critical for checking flexure, proceed with caution.

RAM Concept - Program Shear Reinforcement (2-way slab)

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