Design for Block Shear of Coped Beams with a Welded End Connection

Abstract

This paper presents a numerical study of the block shear strength and behavior of coped beams with welded end connections. The finite-element (FE) method was employed to predict the structural behavior and block shear capacity of specimens tested during a previous experimental study conducted by the writers. In general, the finite-element analysis results compared well with the test results, and the validated finite-element models were used subsequently to further investigate the structural behavior of the connections through a parametric study. The results show that the block shear capacity of coped beams with welded end connections, in general, increases with increasing connection rotational stiffness and increasing web block aspect ratio (depth/width). It was found that, for design purposes, connections with a large web block aspect ratio (large depth and narrow width) should be used to reduce the effects of loading eccentricity between the centroid of the weld group of the connection and the support. The finite-element analysis results also show that, for the coped beams with small connection rotational stiffness, shear yielding only occurs over a small portion of the shear area. Based on the test and the finite-element analysis results, a design equation previously proposed by the first writer for evaluating the block shear capacity of a coped beam with a welded clip angle connection was modified to account for the effects of the connection rotational stiffness. The predictions based on the modified design equation compare well with the test and the finite-element analysis results. The ratio of the test and the FE capacities to the predicted capacities has a mean of 1.01 and a coefficient of variation of 0.05.