Numerical analysis of innovative layered infilled RC frames with rice husk-magnesium oxysulfate cement (RMOC) masonry

Layered infilled RC frame is a novel structural form designed to enhance the ductility of the traditional infilled RC frames and prevent the infilled frames from the brittle failure modes. These layering methods can effectively increase the structural ductility. However, after layering the infill walls, the bottom infill layer, which cannot slide, exerts a constraining effect on the RC frame columns, potentially leading to a short column failure. Additionally, wall layering can also reduce the out-of-plane stability of the infill walls. An innovative layered infilled RC frame (ILIRF) was proposed in the former research to address these issues, utilizing rice husk-magnesium oxysulfate cement (RMOC) masonry. In this study, material tests on RMOC bricks and masonry were conducted. A constitutive model for RMOC material was proposed based on the material test results. Finite element models for traditional infilled RC frame and ILIRF were established, and the accuracy of the finite element models was verified by test results. Finally, a parametric analysis was conducted on material parameters and ILIRF design-related parameters to study their impact on the seismic performance of ILIRF.