承压水开采对天津滨海地铁车站-隧道系统影响的模拟研究

为探索抽水沉降对地铁系统造成的影响,以天津地区软土环境中的地铁车站-隧道系统为例,采用三维渗流-应力耦合数值模拟方法,模拟承压水抽取引起的车站-隧道连接区间沉降情况,研究沉降和差异沉降对整个系统的影响。在一定假设条件下,定量分析地铁车站-隧道系统不同部位的沉降值以及沉降导致的应力集中等现象。结果表明: 1)抽水所在承压水层的压缩量最高, 沉降最大,在向上向下扩展中,压缩量逐渐降低; 2)沉降发生时,车站结构对沉降有一定抵抗,隧道结构抵抗沉降能力较弱,由此引起近站隧道的差异沉降,导致距离车站2 m 附近的隧道顶部产生较大应力集中。

Simulations for Effect of Confined Water Exploitation on Subway Station-tunnel System in Binhai Area of Tianjin

In order to explore the impact of settlement caused by pumping on subway system, three dimensional seepagestress coupled numerical simulation method is used to simulate the settlement caused by confined water exploitation and to study its influence on the station-tunnel system in the soft soil area in Binhai district of Tianjin. Under certain assumptions, the settlement between different parts of metro station-tunnel system and the stress concentration caused are quantitatively analyzed. The results show that: (1) Compression and settlement in confined water layer is the largest, and compression decreases upwards and downwards; (2) When settlement occurs, station structure has certain resistance, while tunnel structure′s resistance is weaker, which causes differential settlement in tunnel near station and large stress concentration at the top of tunnel about 2 m near the station.