连续梁桥质量转动缠绕索装置振动台试验

Shaking table tests on mass rotation wrap rope device for continuous girder bridges

为发挥活动墩的抗震潜能,提升连续梁桥纵向整体协同受力效果,基于功能分离与协同受力原理,提出一种质量转动缠绕索装置。以一典型三跨连续梁桥为例,通过以不同地震频谱特性和地震强度的实际地震波作为激励的振动台试验,分析各类地震作用下等墩高模型和不等墩高模型结构关键位置的地震响应的变化规律。从桥墩墩顶加速度响应、位移响应和墩底应变响应等结构关键位置的试验结果可以看出,装置对于增强活动墩参与连续梁桥纵向整体协同受力的效果较为明显,且随着地震动输入强度的增加,装置的协同作用越发凸显。同时,装置的作用效果与装置本身的缠绕圈数、活动墩的墩高等因素有关,设计时需要根据结构墩高的不同确定装置的合理设计参数,以实现装置的最佳应用效果。

In order to give full play to the seismic potential of the movable support pier and improve the overall longitudinal synergistic effect of the continuous girder bridge,based on the principle of functional separation and synergistic force,a new type of mass rotation wrap rope device is proposed based on the mechanism of wrap rope.Taking a typical three-span continuous girder bridge as an example,the shaking table test is carried out by inputting actual seismic waves with different seismic spectrum characteristics and intensity as excitation,the seismic response with equal pier height model and unequal pier height model are analyzed to explore the synergistic force and shock absorption effect of the device on the continuous girder bridge.Through the test results of the response of the key positions of the structure such as the acceleration response,displacement response and strain response,it can be seen that the effect of the device on the movable bearing pier participating in the overall longitudinal synergistic force of the continuous girder bridge is more obvious,and with the increase of the ground motion input intensity,the synergistic effect of the device becomes more and more prominent,the design intention of the device is realized.At the same time,the effect of the device is related to factors such as the number of wrap rope turns of the device itself,the pier height of the movable bearing pier,etc.The design needs to determine the reasonable design parameters of the device according to different factors such as the pier height to achieve the best effect of the device.