Analysis Of Influencing Factors Of Input Energy During Earthquake Of RC Frame Structure Based On Abaqus

Problem of seismic input energy in the process of earthquake is the basic problem of the energy-based seismic theory, and also the first step to ensure structural energy dissipation ability greater than earthquake input energy. Most of existing research results are based on the response spectrum theory, which simplifies the structure into single-degree-of-freedom(SDOF) system, chooses particular seismic waves and then conducts quantities of seismic response analysis to obtain the earthquake input energy spectrum. This method is easy to conduct and the analysis result can roughly reflect the energy response of the structure. But it fails to fully reflect the nonlinear behavior of the structure in the process of the earthquake. Due to above reasons, this paper fully investigates the input energy of reinforced concrete frame structure during earthquakes and the influencing factors of it, which lays the foundation for the research of energy-based seismic theory.Based on analyzing the characteristics of input energy of the structure in the process of earthquake, as well as the theory of computing structure energy in Abaqus software, this paper selects seismic waves and conducts seismic time history analysis. The main conclusions are as follows:1. The ground motion factors have different degrees of influence on input energy of structure. Input energy increases as PGA increases significantly, but when different seismic waves are selected, this change trend generates large discreteness due to duration characteristics of waves. When the PGA phase stays the same, the input energy also increases as D5-95 factor increases.2. Under selected ground motion records, the input energy of analysis model has a downward trend as the PGA/PGV increases, when PGA/PGV represents frequency characteristics of ground waves.3. The structure factors have no significant influences on total input energy. When the damping factor and ductility factor keep in a reasonable scope, the earthquake input energy changes very small when the two factors changes; but the two factors impact the allocation of total input energy between the damping energy dissipation and plastic energy dissipation.4. For frame structures with the same height, the earthquake input energy has a tendency to reduce when structural natural frequencies increase, even selecting different seismic waves, which illustrates that the bigger structure flexibility, the less energy absorbed.5. The earthquake input energy of structure is mainly affected by the earthquake ground motion factors, but the results always have large discreteness. The main source of discreteness comes from duration characteristics of the ground motions. Sometimes, if the intensity of ground motion is large, the results have some discreteness too. It’s suggested that energy index is adopted in seismic analysis to consider the duration characteristics of the ground motions.