Minimally invasive retrofitting of RC joints with externally applied SMA plate - adaptive design optimisation through probabilistic damage simulation

Abstract

Beam–column joints are the critical section of many reinforced concrete (RC) structure types in which any failure could lead to the collapse of the entire structure. This paper attempts to employ a superelastic shape memory alloy plate as an innovative and adaptive external strengthening element to rehabilitate existing concrete beam–column joints and enhance the structure’s performance. An experimentally investigated beam–column joint is used as the case study, and it is investigated numerically to validate the effects of an innovative strengthening technique based on shape memory alloys. The results show that the proposed technique could increase the joint’s stiffness and reduce the risk of overall failure. A particular innovation in the proposed method is associated with the novel material itself but also with the fact that the increased potential costs of using special alloys are counteracted by its potential to produce these elements in an optimised industrially produced fastened plate. This fits-all construction product further allows a rapid and minimally invasive strengthening technique. Moreover, to achieve this, the plate is adaptively designed against random critical load combinations through probabilistic damage prediction.