泄水式管片衬砌不同泄水方案的流固耦合分析

泄水式管片衬砌是在常规管片衬砌基础上改进的结构形式,可用于TBM施工的高水压隧道工程。本文基于裂隙岩体连续介质流固耦合模型,研究无泄水孔、单环单侧单泄水孔、单环单侧双泄水孔等不同泄水方案下衬砌壁后及围岩内的水压力分布形态、泄流量大小。研究表明:开设泄水孔能明显降低衬砌壁后水压力,泄水孔数量与水压力折减值、泄流量成正向关系,与水压力降低效应增长成反向关系;泄水孔数量变化对靠近泄水孔的衬砌中下部,尤其是泄水孔所在高程,水压降低效应变化明显,而衬砌中上部相差不大;建议泄水孔数量在综合分析设计水压力和水环境保护的基础上确定。

Analysis on Fluid-structure Interaction of Drainage Segment Lining under Different Drainage Schemes

Drainage segment lining is the type of structure improved from conventional segment lining,and it can be used in TBM-excavated high water pressure tunnels.By applying the continuous fluid-structure interaction model of fractured rock mass,the water pressure distributions and flow discharges behind segment liners and in side rock lining were studied under different drainage schemes including no drainage hole,one hole on each side of a ring and two holes on each side of a ring of the segment liner.The results show as follows:The water pressure behind segment lining is reduced obviously by setting drainage holes,and the number of drainage holes is in forward direction to the water-pressure reduction,and flow discharge,and is in opposite direction to the water-pressure reduction effect;the number of drainage holes changes the water-pressure reduction effect obviously in the lower parts of the lining near the drainage holes,especially at the elevation of the drainage holes,but the effect changes only a little in the upper part of the lining.It is suggested that the number of drainage holes should be determined after comprehensively analyzing the designed water pressure and water environment protection.