Significant changes from the 2008 to the 2011 edition of ACI 318

摘要

I am reviewing concrete construction for the Structural Engineering exam. After reading Dr. Ghosh's article "Significant Changes from the 2008 to the 2011 Edition of ACI 318" in the Winter 2013 issue of PCI Journal, I was given the impression that shear is allowed to be calculated either per method (a) or (b) in section 21.3.3, based on wording in the paper: "Section 21.3.3 of ACI 318-08 provided two choices for the calculation of the required shear strength of a column of an intermediate moment frame.". The code has an "and," which requires that both (a) and (b) be calculated and the smaller of the two values be used. Can you please clarify if either (a) or (b) may be used or if (a) and (b) are to be checked per the code? For the designer to have a choice, the code should state (a) or (b), or allows an option, and requires both to be addressed.