Simplified formulas for calculating bearing capacities of standing seam metal roof systems under uniformly distributed downward and upward loads

Abstract

Finite Element (FE) models of standing seam metal roof systems (SSMRSs) are established and verified by experimental results. A comprehensive parametric study on the bearing capacities of SSMRSs under uniformly distributed loads through FE simulations encompassing 281 SSMRSs is conducted. Simplified formulas for calculating the bearing capacities of SSMRSs under uniformly distributed loads are proposed as functions of fundamental parameters, including roof panel thickness, roof panel width, purlin spacing, material strength, friction coefficient, and support head width. These simplified formulas avoid the necessity for calculating the effective section during the verification of bending failure and avoid the necessity for wind uplift experiments during the verification of connection failure of the SSMRSs in conventional building codes and guidelines. The results show that for per 0.1 mm increase in roof panel thickness, the ultimate bearing capacities under downward and upward loads increase by about 14.03 % and 19.88 %; for per 100 mm increase in roof panel width, they decrease by about 27.14 % and 36.45 %; for per 200 mm increase in purlin spacing, they decrease by about 12.82 % and 5.01 %; for per 20 MPa increase in material strength, they increase by about 11.40 % and 2.24 %; for per 0.1 increase in friction coefficient, they increase by about 3.16 % and 9.01 %. Future studies can focus on the ultimate bearing capacities of SSMRSs under non-uniform loads with temporal and spatial fluctuation.