Hello, my office is designing a basement wich consists of a slab for foundation, a concrete reinforced wall and beams and pedestals. The program takes hours to run due to the high number of plates it has (around 22000) but even when it did finish the analysis we opened the output only to see that the values for minimum steel are being calculated in such a manner that the result is half of what it should be; for example if there was an element with a thickness of 0,30 m then minimum steel should be 0,0018*30*100 = 5,4 cm2/m but instead the output says the value is 2,70 cm2/m, the same happens with the clear cover values as they should be 38,10 mm by default but the output is showing values of 19,05 mm, this has led us to believe that these are not viable results and we can´t find the reason for this. Wer´e working with STAAD.Pro V8i SS6. Suggestions are welcome, thanks in advance for any help regarding this issue.
The file is attached here.
SOTANO GIS - MODELO 3 AJUSTADO_3 con 750_2.std
The minimum steel requirement has to be satisfied considering steel on both faces ( top + bottom combined ). So if the minimum reinforcement governs for both faces, the software provides half the steel at the top and half the steel at the bottom face. Regarding the clear cover, it seems like the software is using a default of 0.75 inches or 19.05 mm although the input dialog box seems to suggest that it should be using 38.01 mm. I will bring this to the attention of our development team. Please use the design parameters CLT and CLB to set the appropriate value and it should use those.
On a different note. You should add a LOAD LIST command before the design commands in order to restrict the design to the desired load combinations only
PERFORM ANALYSIS PRINT STATICS CHECK
LOAD LIST 99 TO 173 1300 TO 1365
START CONCRETE DESIGN
...
For the records, the issue is logged in our bug tracking system with id# 996419
Thanks for the reply, I´ll explain what´s happened so far.
Ok so we added the CLB, CLT and CLS parameters and the output is showing the correct values for cover now. We also added the LOAD LIST command as you suggested and additionally the SFACE and EFACE design parameters to obtain the shear and torsion design in the shorter beams. However the output´s no longer showing half the minimum steel values for top and bottom but the complete value; for a 30 cm plate it shows top as 6 cm2/m for example, so that´s my confusion now, why has it stopped showing values in the manner that you previously explained in your response?
Attached the model with the modifications that I mentioned.
4454.SOTANO GIS - MODELO 3 AJUSTADO_3 con 750_2.std