WEB CRIPPLING OF UN-STIFFENED COLD-FORMED CHANNELS WITH CIRCULAR WEB OPENINGS

Although cold-formed channels, CFC, are often manufactured with pre-punched holes in the web, current design codes do not explicitly address the effect of web perforations on flexural members. In this work, the analysis of un-stiffened CFC with circular web openings was conducted using the finite element method. The numerical model and analysis procedure were previously verified by comparison to test results on CFC without web perforations. The finite element model was used to conduct a parametric analysis to assess the effect of circular web openinss outside bearing length on web crippling of CFC for the four web crippling cases stipulated by current design codes. Due to circular web openinp, it was shown that the web capacity was reduced by 2% and 7% on average for end one-flange and end two-flange loading cases, respectively. On the other hand, the web crippling capacity for interior loading cases was not significantly affected. Based on numerical results, an expression for web crippling capacity was proposed for all loading cases considering the effect of circular web openings outside bearing length.