【摘要】 为了研究独塔斜拉桥在强震作用下的地震响应特性,设计制作缩尺比例为1∶30的半漂浮体系独塔斜拉桥结构模型,进行不同地震动作用下多点激励的地震模拟振动台试验.研究结果表明:支座破坏是半漂浮体系独塔斜拉桥缩尺模型在强震作用下的一种主要破坏模式;与只考虑单向水平地震波的情况相比,考虑双向水平地震波同时作用对半漂浮体系独塔斜拉桥的加速度响应影响显著,而对动位移响应的影响较小;在双向水平地震波作用下,主梁跨中会发生不可忽略的竖向加速度响应,卓越周期较长的地震波对半漂浮体系独塔结合梁斜拉桥缩尺模型更具破坏性,强震下斜拉索要承受远大于初始索力的瞬时索力.更多还原

【Abstract】 In order to study the seismic characteristics of cable-stayed bridge with single tower,a 1∶30 scaled model of a semi-floating composite cable-stayed bridge was designed and tested on the shaking tables under multi-support excitations with different strong earthquake waves. The results showthat the bearing damage and failure is one of the main failure modes of the semi-floating composite cable-stayed bridge model under strong earthquake loading. Compared with the case only considering unidirectional horizontal seismic waves,the acceleration responses of the cable-stayed bridge model with the semi-floating system are more affected under the bidirectional horizontal earthquake excitations,but the effect on the dynamic displacement response is less. Under the bidirectional horizontal earthquake excitations,the vertical acceleration at the middle-span of the main girder cannot be ignored. The cable-stayed bridge model with the semi-floating system is more severely damaged under the earthquake waves with the longer predominant period. M eanwhile,the transient forces of the cables are far greater than the initial cable forces.更多还原