单舱地下综合管廊地震动力响应振动台模型试验研究

采用振动台模型试验方法,对EL-Centro地震波作用下单舱地下综合管廊结构动力响应、土体动力响应以及土-结构相互作用机理开展研究。模型试验依托某实际工程为原型,按照1:15的比例尺缩,设计振动台模型试验,输入不同峰值加速度地震波,以此获得管廊结构以及周边土体的动力响应规律。试验结果表明:土体与管廊结构在振动过程中相互制约,存在明显的土-结构相互作用,在强震作用下管廊侧壁和土体出现脱离的情况,单舱管廊结构的运动始终保持了较好的整体性;管廊周边土体由于受到管廊侧壁的约束作用,土体发生不均匀位移或相对位移,动土压力分布形式错综复杂,土拱效应明显;在横向一致地震作用下,管廊结构横向应变随着地震波输入峰值加速度的增强而增大,其中管廊结构中部截面变形最为明显,各截面角点处的变形位移最大,是管廊抗震设计中需要重视的关键部位。

Dynamic Responses Study on Shaking Table Model Test of Single-pile Utility Tunnel

Based on shaking table model test under EL-Centro earthquake wave, model structural dynamic response, soil dynamic response and soil-structure interaction mechanism were investigated. Taking an actual project as a prototype, the shaking table model test was designed according to a certain scale (1:15), and different peak acceleration earthquake waves were input to obtain the dynamic response law of tunnel structure and surrounding soil. The study indicates that soil and tunnel structure restrict each other, and there is obvious soil-structure interaction in the course of vibration. Under strong earthquake excitation, the side wall of pipeline and soil are separated, while the movement of single-pipe tunnel structure always keeps a good integrity; Because the soil around the pipe gallery is affected by the side wall, non-uniform displacement or relative movement of the soil takes place, and the distribution of dynamic earth pressure is complicated, the soil arching effect is obvious as well; Under transverse uniform seismic excitation, the transverse strain of the pipeline structure increases with the rising of the peak acceleration of seismic input. The deformation of the middle section of the pipeline structure is the most obvious, and the deformation displacement at the corner of each section is the largest, which is the key part in the anti-seismic design of the utility tunnel.