Structural performance of bolted moment connections between cold-formed steel members

摘要

The paper presents findings of an experimental investigation [1] on cold-formed steel members with bolted moment connections. A number of connection configurations with gusset plates of both hot rolled steel plates and cold-formed steel strips were tested to investigate the structural performance of bolted moment connections among cold-formed steel members. The investigation aims to quantify the maximum moment resistances of the connections which may be safely mobilised in practical connection configurations, and a total number of 16 component tests and system tests on bolted moment connections between double lipped C sections with interconnections were carried out. In the proposed connection configurations, only the section webs are connected onto the gusset plates while the section flanges are not connected for ease of installation. Consequently, incomplete load path exists in the connections and the moment resistances of the connections are found to lie between 50% and 85% of the moment resistances of the connected members. It is thus demonstrated that bolted moment connections among cold-formed steel members are feasible and also structurally economical. However, rational design on connection configuration is required to provide effective load path across the connections. Based on the stress distribution of a finite element analysis, a simple design expression is proposed to allow for the partial effectiveness of the section flanges at the connection.