Comprehensive analysis of structural and thermal performance for the concrete and steel joints used in the assembled building

Abstract

The structure joints and connection type of buildings play a decisive role in their safety and reliability. Therefore, most studies have focused on the structural performance, ignoring their thermal performance. Three common assembled concrete joints and four steel joints usually used in the assembled building were selected to study their bearing capacity, seismic performance and stiffness degradation. In addition, the temperature and relative humidity distribution of six types of envelopes were evaluated within a year and the effect of different envelope options on the linear thermal transmittance of each joint was investigated. The results show that the best structural performance of concrete joints and steel joints are the grouting sleeve joint and the cantilever section bolt connection respectively. The seismic performance of steel joints is generally stronger. Furthermore, for every 25 mm increase in AAC thickness, the overall linear thermal transmittance of the component increases by 0.02–0.04 W·m−1·K−1. On balance, the grouting sleeve joint is the optimal concrete joint in terms of both structural and thermal performance, but better damp proofing measures are necessary outside of it. Moreover, the cantilever section bolt connection is the optimal steel joint and requires better insulation measures. Interestingly, the building envelope construction of “75 mm autoclaved aerated concrete + 90 mm mineral wool + 75 mm autoclaved aerated concrete” is the best choice for matching joints.