Structural Behaviour of Power-Actuated Fasteners in Hybrid Steel Connections

This thesis presents research into a novel connecting method using Power-Actuated Fasteners (PAFs) in hybrid steel connections comprised of cold-formed steel (CFS) and hot-rolled steel. The first experimental program investigated the shear behaviour of PAF connections in three different limit states: (i) bearing, (ii) shear fracture, and (iii) pull-out by shear. The test results validated the design provisions of PAF connections in AS/NZS 4600:2018 and AISI S100-16 with suggested revisions. Numerical investigations using Finite Element Analysis were conducted using ABAQUS. Various aspects of the models (i.e. fracture criteria, mesh sensitivity) were thoroughly examined and discussed. In the second experimental program, Cross-Tension tests were carried out to investigate the behaviour of PAF connections under tension loading. An analytical model is proposed to evaluate the pull-out strength of the PAF connections. Reliability analyses are carried out to evaluate the capacity reduction factor of the proposed model for LRFD/LSD. The third experimental program used a dual-actuator test apparatus to test full-scaled PAF connections joining CFS channels to rectangular hollow sections. The test results revealed the detrimental effect of the rotation on the shear capacity in two different limit states: (i) bearing and (ii) pull-out by shear. An analytical model is proposed to capture the shear-rotation relationship of PAF connections subjected to shear-rotation. Design proposals are made with two design examples to illustrate the implementation of the proposed model in the conventional design routine