摘要
在高水头富水区 ,抗水压衬砌设计的关键在于外水压力的计算。深埋隧道排水时 ,沿轴线方向上流入隧道的水量来自于隧道掌子面的前方 ,当隧道施工足够长度后 ,可以认为已施工断面的地下水只从隧道两侧向断面内运动 ,此时可将三维问题处理为二维。对于深埋隧道 ,当其断面远小于水头时 ,可处理为一个点井 ;隧道全断面排水时 ,隧道断面线可处理为定流量边界。首先建立隧道排水的水文地质概念模型 ,采用经验解析法预测隧道的涌水量 ,然后将涌水量代入隧道围岩渗流的剖面二维模型 ,模拟隧道排水时围岩渗流场的分布 ,再采用作用系数的方法计算出隧道衬砌的外水压力。
The correctly design of tunnel lining, in the area with high groundwater table, lies in the accurate calculation of external water pressure. When a tunnel is excavated to a certain length, the groundwater drained from the aquifer ahead of tunnel face can be ignored, and the 3D\|seepage problem can be simplified to 2D\|one. If a deep tunnel's dimension in section is far less than water head, the deep tunnel can be regarded as a horizontal point well. The blow of a deep tunnel can be calculated by analytical method. Taking the outflow rate into seepage's mathematical model, water head of a deep tunnel's aquifer in section can be obtained by numerical method. Then the external water pressure can be obtained by the coefficient according to the water table simulated above.
出处
《水文地质工程地质》
CAS
CSCD
2002年第3期17-19,28,共4页
Hydrogeology & Engineering Geology
基金
国家自然科学基金项目 ( 4 9872 0 82 )
