Experimental and acoustic emission investigation of recycled concrete and expanded perlite aggregate dapped wet connections for precast concrete wall panels

The utilization of precast wall panels has gained prominence due to its potential for enhancing construction speed, quality, and sustainability. One critical aspect of precast construction is the connection between wall panels, where it is one of the proven to be the weakest link in the system. Rigidity of the connection between panels was also a point of concern. This study was a part of bigger project in developing a new precast wall system with recycled concrete aggregate (RCA) and expanded perlite aggregate (EPA) in partial replacing natural fine aggregate, with primary and secondary objectives were to investigate the mechanical performance of the dapped wet connection models and their variations which are dapped wet (T1), horizontally lightly reinforced dapped wet (T2), vertically lightly reinforced dapped wet (T3), and cross dapped wet (T4) in the vertical wall-to-wall connection in application for precast wall panels, by focusing on shear load, respectively. The third objective was to assess the damage occurred with respect to their crack propagations through visual inspection, which was then verified using acoustic emission (AE) technique in the fourth objective.