Failure capacities of cold-formed steel roof trusses end-connections

The response of cold-formed steel roof trusses undergoing large deformations resulting from unconventional loading is not totally known. Roof truss end-connections are one structural component that can cause premature failure. This paper investigates the failure capacities and the energy absorption capabilities of roof truss end-connections. Experimental tests were performed to obtain the capacities of these connections under quasi-static vertical and horizontal (tension and shear) loadings. Numerical simulations were developed to predict the connection response to failure for any configuration. Implicit and explicit dynamic procedures were used in the analysis of the numerical simulations. A deformable screw behavior with failure criterion was used in the numerical modeling to predict the progressive failure of the connection. The paper includes four verifications that validate the deformable behavior of #10 TEK screw used in the simulations. Results showed that the toughness (energy absorbed to failure) of the end-connection is greatly affected by the screw configuration and the direction of loading.