Progressive collapse mechanism of RC framed structures under earthquake using energy method

다국어 초록 (Multilingual Abstract)

In this paper, the effect of earthquakes on the progressive collapse mechanism of reinforced concrete (RC) frame structures was studied. The step-by-step numerical integration method for energy was used in analyzing the progressive collapse of RC framed structures. The Q-model was employed to analyze the progressive collapse mechanism of RC frame structures, considering the practical challenges associated with step-by-step numerical integration in multi-degree-of-freedom (MDOF) systems. This approach allows for the utilization of an equivalent single-degree-of-freedom (SDOF) system in step-by-step numerical integration analysis. Using time history analysis, the maximum displacement and hysteresis energy of the equivalent SDOF systems were computed. Based on the double control damage, the damage indexwas determined, providing an objective evaluation of the dynamic characteristics and damage extent of the original MDOF systems. This approach simplifies progressive collapse analysis of MDOF systems in subsequent studies. To verify the accuracy of the Q-model method, the damage of two multi-story RC frame structures was calculated based on experimental models. The numerical results closely match the experimental findings, demonstrating the accuracy of the method. Finally, the discussion of beam hinge mechanisms for RC frame structures, an efficient measure to strengthen the progressive collapse-resistant ability of RC framed structures, was discussed. The evaluation theory for progressive collapse mechanism and damage of RC framed structures under earthquake using energy method was put forward. This study has practical significance and provides a reference for the study of the progressive collapse of RC framed structures.