Finite element modeling of large capacity stiffened steel tee-hanger connections

Abstract

This paper presents the development of a mathematical model describing the behavior of a stiffened steel tee-hanger connection. The particular tee-hanger connection has two rows of pretensioned high-strength bolts on either side of the tee-stem (eight bolts total). This geometric configuration results in a highly indeterminate problem as the bolt forces cannot be determined directly. Thus, an analytical study with modeling of the connection as an assemblage of finite elements was conducted. Only one-quarter of a symmetric section of the tee-hanger was analysed with eight-noded isoparametric brick elements used for the tee-flange plate elements. Bi-linear stress-strain behavior is considered for both the bolt and plate material. To consider the inelastic steel behavior in each cycle, the elastic moduli of the yielded elements are reset to their secant values. Analytical results are compared with results from tee-hanger connection tests. Based on comparison of experimental and analytical results, it is concluded that the model developed adequately explains the connection behavior. The study is restricted to A36 steel and A325 bolts with maximum diameter of 1 1 2 inches.