Cracked Concrete Sections 1

[mpirez]

Does anyone know if ETABS Plus (v.8.3.5) takes into consideration the reduced moment of inertia in the frame due to the presence of cracked regions along the lengths of the members? This is a requirement of ACI 318-99 section 10.11.1.
Thanks,
Monica

 

[amadeus]

If it is considered, they don't make any reference to it in the manuals or the online help of the program. But given the actual inaccuracy in the determination of the loads and the material properties such a refinement does not make much sense.

 

[coco1953]

Monica: You can handle the issue via the modification factors available at the Define Frame Section dialog box. Understandably ETABS doesn´t have an automatic option for that because this approach is not widely applied. Actual limitations for lateral drift require shearwalls that make the influence of the lateral stiffness of columns less relevant. Experiment and find the differences. COCO

 

[Murali27]

Monica,

Better that you can modify the stiffness modifiers for columns & other structural elements as per ACI 10.11.1
(both ultimate load case & service load case)

Hope this helps to you,

Murali