引汉济渭工程黄三段深埋长输水隧洞排水方案研究

以有效解决深埋长输水隧洞排水问题为目标,按富水性将隧洞沿线围岩划分为中等富水区、弱富水区和贫水区,采用数值方法模拟衬砌周边渗流场,分析了不同排水设计方案对引汉济渭工程黄三段深埋长输水隧洞衬砌外水压力的影响。结果显示,对于高外水压力情况,将排水孔布置于顶拱处仅能降低顶拱附近的外水压力,无法有效降低作用于底板的外水压力,而排水孔沿衬砌周边均匀布置时,可有效降低作用于衬砌上的外水压力。基于此,讨论了各排水方案的适用条件,给出了深埋长输水隧洞排水设计建议。

Study on drainage scheme for long deep-buried water conveyance tunnel of Hanjiang-to-Weihe River Valley Water Diversion Project

In order to solve the drainage problems of deep buried long water transfer tunnels effectively, the surrounding rock along the tunnels is divided into medium rich water area, weak rich water area and poor water area. The influences from different drainage design schemes on the external water pressure acting on the lining of the long deep-buried water conveyance tunnel for Huangsan Section of Hanjiang River to Weihe River Water Transfer Project are analyzed herein by simulating the circumferential seepage field of the lining with the relevant numerical method. The result shows that for the condition of higher external water pressure， if arranging the drain-holes at the arch-crown， only the external water pressure near the arch-crown can be lowered， but the external water pressure acting on the bottom slab cannot be effectively decreased， however， when the drain-holes are uniformly arranged along the circumference of the lining， the external water pressure acting on the lining can be effectively decreased. On the basis of this， the adaptable conditions for all the drainage schemes are discussed， and then the relevant suggestions on the drainage design for the long deep-buried water conveyance tunnel are put forward as well.