RESEARCH ON COLLAPSE AND DAMAGE EVOLUTION OF REINFORCED CONCRETE FRAME STRUCTURE UNDER SEISMIC FORCE

摘要

Elastoplasticity displacement time history response of the structure under seismic force is analyzed by nonlinear dynamic finite element method. The damage index of member is calculated by the improved double parameter damage model based on distortion and dissipation. The damage index of holistic structure is calculated with weighted method. The process of structure collapsing is defined quantificationally by damage index based on three-level seismic fortification objective. The analysis shows that the improved damage index model can describe the process of structure collapsing quantificationally and continuously. The damage evolution equations of beams, columns and holistic structure are fitted and the damage evolution rules of frame structure are studied. The damage evolution equations of the beam and the column based on the two variables of the number of layer and time are put forward. The damage evolution rules of holistic structure accord with the design principle of strong column and weak beam by the optimal fitted equation of the damage index.