Pre-qualification of groove welded connections between equal-width RHS

摘要

The paper describes a series of experimental tests on tension coupons cut from the groove welded brace-to-chord connections (T-joints) between cold-formed RHS having equal widths. The aims of the tests are to investigate whether there are any serious difficulties in producing satisfactory groove welds in the large root gaps resulting from the rounded corners of cold-formed chord sections, and to establish the welding procedures that enable such connections to be pre-qualified for complete penetration groove welds. Rectangular hollow sections of various thicknesses and corner radii are used, resulting in root gaps ranging from 0.8 mm to 9.4mm. Four different types of joint preparations involving the use of backing strips, backing rods, purging gas or no preparations at all are experimented with. The connections are fabricated using the GMAW and the MMAW processes. It is concluded that a complete penetration groove weld in a brace-to-chord connection between equal-width RHS may be pre-qualified under certain conditions.