Tensile behavior of cruciform stubs with four bolts per row

Abstract

The stiffened top-and-seat angle connection is widely used in earthquake-prone areas, and additional tensile bolts on angles' column leg effectively improve its bending behavior. However, such design and construction are not governed by any regulations. It is urgent to figure out the mechanical behavior and develop accurate theoretical methods. Based on the component method, this paper first conducted an experimental study on the extracted cruciform stubs with four bolts per row. It compared the tensile properties and damage modes for different thicknesses. After that, the further parametric analysis compared the impact of stub thickness, bolt arrangement, and whether or not the bolt was pretensioned after validation. Stub thickness and bolt gauge were observed with a greater impact than the bolt distance on the plastic resistance. Furthermore, a prediction model for the plastic resistance of the cruciform stub with four bolts per row is proposed by integrating approaches for classic stiffened and unstiffened angles.

Optimization of Bolted Joints: A Literature Review

“…The result from the study makes it feasible to specify the angle thickness and bolt type in practical design, and it would be preferable to have an initial stiffness calculation method with stiffeners having a staggered bolt pattern [25]. In another study, where a cruciform stub with four bolts in a row was proposed, it was concluded that the stub thickness and bolt gauge impact the plastic resistance more than the bolt spacing [26]. The different layouts, in-line, rectangular, and circular, were studied to minimize the tensile stresses in the T-stub connections.…”