Flexural Performance and Deflection Prediction of the Drop Panel-Type Double Composite Beam System

The double composite beam system with drop panels is a structural system developed for high-rise buildings with long spans. This system aims to reduce floor height by decreasing the depths of flexural members while minimizing deflection through the incorporation of stiff drop panels at both ends of the span. For a double composite beam system with drop panels, it is essential to assess whether the frame can exhibit adequate flexural and deformation performance under repeated lateral loads, such as those induced by earthquakes, given the varying cross-sections of the flexural members. Experimental results on flexural strength indicate that all specimens demonstrate sufficient flexural performance, with smooth load transfer between members. When predicting deflection using the elastic load method, the results showed good agreement with the experimental outcomes, confirming the method’s validity for predicting negative moment-induced deflection.