Experimental and numerical studies on self-centring beam-to-column connections free from frame expansion

TL;DR: In this article , the authors explored the seismic behavior of self-centring hybrid-steel-frame (SC-HSF) employing energy dissipation sequences and the corresponding inelastic seismic demand model.

TL;DR: This study presents a novel hybrid self-Centering system aiming to overcome critical shortcomings identified in the existing self-centering solution.

TL;DR: In this paper , the authors summarize the latest technological advances, especially those developed in recent few years, in diverse aspects including novel SMA elements and their applications in steel, timber and reinforced concrete (RC) buildings and bridges.

TL;DR: In this paper, the authors present 10 tests on a self-centering sliding hinge joint (SHJ) subassembly with a combination of ring springs and asymmetric friction connections, with the proportion varied between tests.

TL;DR: In this paper, the authors provide an update on how economic activity and prices in the Canterbury region have been affected by the 2011 Christchurch earthquake and the progress made to date in the rebuild.

Abstract: This paper discusses the manufacturing process and mechanical performance of a novel self‐centring damper equipped with a group of kernel elements, namely, shape memory alloy (SMA) ring springs. The study commences with an experimental investigation on individual SMA ring spring specimens, enabling a fundamental understanding of their working principle and mechanical performance. Some technical issues related to manufacturing process, low‐temperature heat treatment (annealing), quenching, and cyclic training are also discussed. Subsequently, the fabrication steps and working mechanism of the dampers incorporating the SMA ring springs are elaborated, and a further experimental study on a large‐scale prototype damper specimen is carried out. The test results show that the damper specimen exhibits satisfactory mechanical behaviour with a stable flag‐shaped load–displacement hysteretic response. A high initial stiffness and an adequate level of “yield” resistance are exhibited due to a relatively high preload applied to the SMA ring spring group. Excellent self‐centring capability with no residual displacement is observed, and satisfactory energy dissipation with an equivalent viscous damping ratio of up to 18.5% is shown. No failure to any component of the damper is observed by the end of the test. The proposed damper is expected to resist strong earthquakes and offer self‐centring driving action effectively for engineering structures without the need for repair.

TL;DR: In this paper, the influence of the floor diaphragm stiffness, strength, and configuration on the seismic response of self-centering moment resisting frames (SC-MRFs) is examined.