Shear testing and analysis of the response of confined masonry walls with centered openings made with innovative sintered insulation shale blocks

摘要

The innovative sintered insulation shale (SIS) blocks could use as thermal insulation masonry units to construct the green architecture applying the adaptive construction measures. Above all, the seismic behavior of the wall with an opening should clarify in order to apply in earthquake region. Besides the comparative solid wall, the behavior of typical window-type and door-type walls analyzed under the cyclic lateral loads incorporating with the constant vertical load to achieve the purpose. The main variable of the specimens was the size of the opening. Hence, all the walls were with the same innovative construction measure and geometry parameter. The failure mechanism, energy dissipation, damping ratio, lateral stiffness, deformation and strength capacity conducted according to the record data. Based on the results, the opening caused the weaker masonry parts showing serious damage in wall piers and masonry under the opening, which mainly induced for the lack of restrained condition around the opening. In other words, it changed the failure mechanism. Furthermore, the contribution of RC level bonds and tie-columns to the specimen increased as the opening showing the greater strain than yield strain after the maximum strength, which need to take into account their participation in the lateral resistance calculation. The impact of opening still presented in the decreased lateral stiffness and energy dissipation, smaller ductility and shear strength. The reduced portion would result in the opening wall acting as the weaker part in the SIS masonry structure. In addition, the theoretical equations acquired through Strut-and-Tie method proposed considering the failure mechanism and opening impact. The reduction factors for decreased stiffness and angle of masonry strut, relative stiffness between the RC components and masonry parts applied to conduct the calculation of the maximum strength. Compared with the experimental results, the proposed equations showed enough accurate prediction on the maximum shear resistance.