The Research Of Composite Isolation System

Composite isolation technique is a new technique using rubber bearing isolation and sliding isolation, which fits together in some way. Via the reasonable parameters, this technique can take two traditional isolation techniques to make up each other, make full use of their merits and get over their shortcoming effectively. Therefore, it gets the good isolation effect. The composite isolation system with rubber bearing and the elastic sliding plat in parallel has some merits such as isolating slight earthquake, offering restore force to reduce the remaining displacement after earthquake and preventing rubber bearing's oversize displacement. Further more, other composite isolation systems can be considered as the special case of this composite isolation system. Therefore, to this composite isolation system, through time history analysis and mechanics analysis , this dissertation studies it's isolation performance, the mechanics characteristic of isolation bearing and the effect regularity of various isolation parameters affecting the isolation property. This investigation can offer basic theory foundation and reference for engineering designer dealing with design and application of composite isolation systems.Firstly, in this dissertation, time history analysis is proceed by software and then the isolation property of several parallel and series composite isolation systems, traditional rubber bearing isolation system and traditional earthquake-resistance system are compared. It is proved that composite isolation systems have better isolation effect than the traditional rubber bearing isolation system, whether at the aspect of absolute acceleration or interfloor displacement of upper structure.In order to insure that the horizontal displacement of the elastic sliding plat's rubber doesn't exceed the code's specification before sliding plats begin to slide, and to make use of the dissipative function of elastic sliding plat. According to whether the rubber bearing's shear-buckling effect should be considered ,design formulas with which each parameter of elastic sliding plat must satisfied are derived by the calculation formulas of rubber bearing's horizontal stiffness. This will offer necessary theory foundations to the elastic sliding plat design.In the aspect of the time history analysis way about composite isolation structure, the case of composite isolation using lead rubber bearing or the case that hysteresis of isolation storey is arbitrary multi-linear model is transformed equivalently to the case that common rubber bearing connect with several elastic sliding plats in parallel. Based on the way of NEWMARK— β , a time history analysis way is advanced ,which can be used when the upper structure is shear model of mass point series and composite isolation is used in isolation storey or the hysteresis of isolation storey is arbitrary multi-linear model. Furthermore, the way of simulating elastic sliding plat by the non-linear linker of friction pendulum in SAP2000 is advanced.Based on the time history analysis program which is established through this dissertation's way, analysis is done in many parameters association case of isolation storey. The preliminary regularity of each parameter of the isolation storey hysteresis affecting the structure response in each association case and the corresponding better...