Numerical Simulation Of The Process Of Reinforced Concrete Framework Collapsing Under Seismic Force

The mechanism of collapse of reinforced concrete structure is discussed. It is believed the collapse of reinforced concrete framework is a process in which the structure undergoes damage and the damage accumulate ceaselessly. So through the study of damage accumulation of framework element and whole structure in earthquake can learn its collapsing process.In order to describe the damaging value of structure under earthquake, the damage parameters based on elastic transformative energy is proposed, which is used to study the damage on section ,component and the whole structure. During dynamic analysis of framework, according to mechanical performance of reinforced concrete frame structure under seismic force, the element of beam and column can be simplify into 5 pole element whose stiffness is variable. Then damage model of 5 pole elements with variable rigidity can be established if the damage parameters based on elastic transformative energy are generalized into pole elements. In this paper the reinforced concrete frame is simplified into pole model and hysteretic model in pole section with consideration of reduced stiffness. The failure criteria is whether the structure has formed mechanical angle.On the basis of the theory and computing method in this paper, the author worked out corresponding program to compute hysteretic model on section and damage value of the structure under seismic force at different time. Then the numerical simulation of the collapsing process of reinforced concrete structure is thus realized.At last, take a three-storeyed and two-span reinforced concrete frame as example, its damage value under cyclic load at different time is computed by the program. And the damage evolution curve of different element and whole structure is also obtained. As result the damage evolution law of reinforced concrete structure under cyclic load is found, which provides basis for the study of collapsing mechanism of reinforced structure under seismic force.