| Among the many experimental devices for structural seismic experiments,the large reaction wall device based on Electro-hydraulic Servo experimental system has become an important test facility for large-scale structural seismic experimental research because of its many advantages.However,with the continuous construction of large reaction wall experimental device,the problems in its structural design are becoming more and more prominent.The large-scale prestressed reaction wall structure lacks a set of targeted and universal mature structural design scheme.Due to the high requirements for stiffness and crack resistance of reaction wall,engineers are often too conservative in the design of reaction wall.At the same time,there is a lack of research on the design of loading hole on reaction wall.Therefore,on the premise of ensuring the deflection limit and crack control requirements of the reaction wall structure,how to design the reaction wall structure economically and reasonably is a subject of great research value.This paper takes the large-scale prestressed reaction wall structure built at home and abroad as the engineering background.Through theoretical derivation and finite element simulation,the structural design method of reaction wall device,theoretical calculation formula in normal use stage,parameter optimization of reaction wall device and loading hole design are studied.The main research work and results are as follows:(1)In this paper,nearly 20 large reaction wall structures at home and abroad are investigated in detail,which provides a reference for the preliminary selection of reaction wall devices,and finally obtains the principles of planning layout and structural selection of reaction wall,which provides a basis for the preliminary design of reaction wall.The theoretical calculation model of the reaction wall in the normal service stage is studied.Considering the shear deformation of the reaction wall,the weakening effect of the web door opening of the reaction wall and the effective section width of the reaction wall,the deflection and normal stress formulas of the box section reaction wall under three loading forms of concentrated load,uniformly distributed load and inverted triangular load are derived for designers to carry out section design The lateral displacement check and the subsequent prestressed reinforcement design of the reaction wall provide a reasonable and effective reference.(2)The finite element simulation of unbonded prestressed steel strand and the simulation of the application method of prestress are analyzed.In this regard,the main parameters of large-scale prestressed reaction wall structure are studied,including the effects of concrete axial compressive strength,reaction wall flange thickness and prestressed steel strand reinforcement ratio on its normal use.Thus,the selection principles of parameters in the design process of reaction wall structure are obtained,which provides an economic and reasonable basis for designers.(3)Combined with Reissner’s plate theory,the weakening of loading hole on local deflection and stress of reaction wall panel is simulated and analyzed by finite element method,and a set of reasonable design method of loading hole is put forward. |
