Mechanical properties and analytical model of a novel dissipative angle bracket for CLT structures

Abstract

The connections are essential in providing the strength, stiffness, ductility, and energy-dissipating capacity for CLT structures. In this paper, a novel dissipative angle bracket for CLT structures was proposed, which combines the benefits of soft-steel brackets and high-damping rubber to offer great energy-dissipating capacity and high ductility. Both quasi-static monotonic and reversed cyclic loading tests were conducted to evaluate the failure mechanisms and mechanical properties of this connection. Failure modes, including the rupture of steel ribs, fracture of the CLT wall, and debonding of the CLT slab, were observed during the tests. The rupture of steel ribs is the controlled failure mode, but the connection can still work as a whole to resist applied load after the steel ribs’ failures thanks to the rubber that is effectively bonded to the steel bracket. The tested connections’ load-displacement curves exhibit a bi-linear form, with the yielding point resulting from the yielding of steel ribs. Almost all the tested specimens have a ductility larger than 9.0 and an equivalent viscous damping ratio of around 10%–22%, indicating high ductility and energy-dissipating capacity. Furthermore, a simplified analytical model of the novel dissipative angle bracket was established. Comparison with test results demonstrates that the proposed model can reasonably estimate the initial stiffness, post-yield stiffness, and yield force. The outcomes of this study are expected to provide valuable references for future research and potential applications of the novel dissipative angle bracket for CLT structures.