Seismic Investigation of Interior Reinforced Concrete Sand-Lightweight Concrete Beam-Column Joints

摘要

The use of sand-lightweight concrete made with expanded shale aggregate has become prevalent in recent years. Sand-lightweight concrete is approximately 20% lighter than its normalweight counterpart based on the incorporation of coarse lightweight aggregate. Earthquake forces applied to a building structure are directly proportional to its mass, so the potential for better seismic performance is clear. However, concrete made with lightweight aggregate is more brittle in nature than normalweight concrete and, as such, is less ductile. This study focused on determining the behavior of reinforced sand-lightweight concrete beam-column joints of moment frame buildings by subjecting six half-scale test specimens to quasi-static cyclical loading that gave an indication of their ductility in a seismic event. This study found that, if designed and detailed in accordance with current code provisions and if joint shear stress is kept within a reasonable limit, high-strength, sand-lightweight beam-column joints can perform as well as similarly-built normalweight concrete specimens.