Experimental investigation of bolted end-plate angle splice in encased composite columns

Abstract

This study investigates a bolted end-plate splice of steel angles for encased composite columns. For the splice, two end plates, each of which is welded at the end of the spliced angle, are butted to each other, and connected in tension by one or three high-strength bolts. Since the centroids of the angle and bolt sections do not coincide, the deformation and prying force occurring at the connection need to be considered for design. Thus, the minimum thickness of end plate is proposed based on the yield line theory, and the tensile strength of the connection decreased by the prying force is estimated. The strength and failure mode of the connection are investigated through the direct tension tests of bare angle splice, and flexural tests of encased composite column with angle splice. The tests have shown that the connection is susceptible to slip and fracture in the threaded portion of bolt. In addition, the proposed minimum end-plate thickness and connection strength agree well with the test results.