Study And Application Of Slab Isolation And Energy Dissipation Technology In Precast Concrete Structure

The precast concrete structure,which was constructed in a unique method of the members being precast firstly and the cast-in-situ connection being constructed later,was influenced poorly by the defects of poor mechanical properties and easy to be damaged and cracked.The structure of slab isolation and energy dissipation(SIED),composed of multiple isolation slabs,the isolation slabs of which distributed in different floors or different positions on the same floor plane.In combination with the construction method of precast concrete structure and the characteristics of SIED structure,some slabs are set as the isolation slabs to form the SIED system for playing the role of shock absorption,so as to reduce the value of internal force of the connection part of post-pouring for the purpose of protecting the whole structure.The system of whole structure is composed of SIED system and the system of main structure.Parameters,such as natural frequency,damping ratio,the number ratio of isolation slab to common slab,and the position of isolation slab in the main structure of SIED system,could be the sharp influence to the main structure in it’s dynamic response.therefore,a systematic study would be given in this paper for researching the influence of dynamic response of the main structure system with the parameters of SIED system.The main task of this paper is:(1)The dynamic analysis model of precast concrete SIED structure was established and the differential equations of motion for the main structure system and SIED system are derived,which were set up for the differential equations of motion of the whole structural system.(2)The dynamic simulation analysis model of Simulink,divided into linear and nonlinear elastic dynamic simulation analysis model of Simulink,was constructed with the simulation analysis framework of the whole structural system.(3)The linear elastic dynamic simulation model of Simulink for the study of parameters of SIED system with the established basic calculation model and the selected excitation effect inputting the calculation model.The influence of SIED system parameters on structural dynamic response and the optimal value or range of these parameters are obtained.(4)The conclusion of parameter study of SIED system was applied to the design of precast concrete SIED structure corresponding to engineering example model with 6layers,which was inputted with three selected severe seismic waves.Inelastic seismicresponse analysis,made with nonlinear dynamic simulation model of Simulink based on Bouc-Wen model,has proven the effectiveness of parameter study.The comparison of the simulation results between the cast-in-site concrete structure and the precast concrete SIED structure from the same engineering example model,which has shown that the cushioning effectiveness of SIED system in structural displacement and restoring force between layers of the structure,and the damage rate of the lateral components also could be reduced,which would enhance the ability of structure to resist collapse under strong earthquakes.