砌体结构外套预制钢筋混凝土墙板加固及隔震加层振动台试验研究

为研究砌体结构外套预制钢筋混凝土墙板加固技术的加固效果，并探讨在其顶部隔震加层的可行性，进行了3个相似比为1/4模型的振动台对比试验， 模型分别是加固砌体结构模型、加固后加层非隔震结构模型和加固后加层隔震结构模型。试验测试了模型结构的动力特性及其在不同地震作用下的动力响应，为了分析结构震损后的动力响应，在试验模型经历罕遇地震作用下的损伤后又继续进行不同水准地震输入试验。试验结果表明：加层非隔震结构的上部钢框架鞭稍效应非常明显；加层隔震结构有效延长了结构自振周期，增大了结构阻尼比。加层隔震结构既有效降低了下部砌体结构的地震响应又降低了上部钢框架的地震响应，其加固效果和抗震性能优越。同时，震损后加层隔震结构的隔震效果明显降低，下部砌体的加速度反应可能大于加固结构和加层非隔震结构，建议在设计时充分考虑这种不利影响。

Shaking table test of masonry structures strengthened with external prefabricated reinforced concrete wall and with added story isolation

In order to research the reinforcement effects on masonry structure strengthened with external prefabricated reinforced concrete wall and investigate the possibility of added story isolation on the top of reinforced masonry structure, the shaking table tests of three 1/4 scaled models were conducted. These three models were reinforced masonry structure model, reinforced masonry structure with added story model and reinforced masonry structure with added story isolation model. The dynamic characteristics and seismic response of models were evaluated under different levels of earthquakes. And then, the models subjected to rare seismic cases were tested again to analyze the dynamic responses of damaged structures.The results indicate that added story isolation structure can prolong the structural vibration periods efficiently and increase the damping ratio. Whiplash effect of superstructure of added story non-isolation structure is very obvious. Added story isolation structure can not only reduce seismic response of the substructure effectively, but also reduce the seismic response of the superstructure; therefore, reinforcement effect and seismic performance of added story isolation structure are significant.On the other hand, the isolating effect of seismic damaged structure will be decreased obviously. Acceleration of lower masonry may be larger than those of the other two models. The negative impact must be taken into account in the design.