浅谈均匀布置减震器的结构与隔震结构的地震激励响应区别

The difference seismic dynamic response between structures with distributed vibration absorber and structures with seismic isolation

隔震结构是目前普遍应用的减震结构,其减震效果已经得到实际工程的验证,但由于隔震支座集中设置在某一层,在某些不利情况下隔震结构会产生倾覆。结构在地震作用下的变形和位移本质上是一种以地震激励为输入的多质点体系强迫振动,为了解决隔震结构的倾覆问题,可以分别调整结构的质量分布、刚度分布和阻尼分布来改变结构的动力特性。传力路径简单明确,结构布置均匀对称的设计方法对减震结构仍然适用。当采用一种随楼层质量均匀布置减震器的减震结构时,理论上可以消耗全部的地震输入动能,使得结构在地震波激励下的动力响应趋于最小,并通过算例比较其动力响应与基础隔震结构的地震激励响应的区别。通过对比可以得出结论:随楼层质量均匀布置减震器的减震结构其减震率高于一般隔震结构的减震率,其消能减震性能高于一般隔震结构。

Seismic isolation structure is currently widely used,its shock-absorbing effect has been verified by the actual project,but because the isolation support set in a certain level,in some adverse circumstances,the structure will cause collapse.The deformation and displacement of structure under seismic action is essentially a forced vibration of multi-mass point system with seismic excitation,and in order to solve the problem of collapsing,the mass distribution,stiffness distribution and damping distribution of structure can be adjusted to change the dynamic characteristics of structure.The transmission path be simple and clear,and the design method of even symmetry of structure arrangement is still applicable to shock-absorbing structure.When shock absorbers are evenly arranged with mass,which theoretically consumes all the seismic input momentum,so that the dynamic response of the structure under the seismic wave excitation tends to be minimal,and the difference dynamic response and the seismic excitation response between structures with distributed vibration absorber and structures with seismic isolation is compared by the examples.By comparison,it can be concluded that:structures with distributed vibration absorber shock-absorbing rate is better than traditional seismic isolation structure,and its de-energy damtening performance is better than seismic isolation structure.