悬挂式帷幕基坑涌水量计算及插入深度影响效应研究

Study on Seepage Volume Calculation of Suspended Curtain and Effect of Depth into Soil

为确定悬挂式止水帷幕插入深度和基坑内涌水量、基坑外最大水位降深的关系,从而得出在预定基坑外最大水位降深和基坑内涌水量下的较优悬挂式帷幕的插入深度,根据达西定律和大井简化的均质含水层潜水非完整井的基坑涌水量计算公式,推导出帷幕插入深度、基坑涌水量、基坑外最大水位降深的关系式。将推导的公式进行基坑实例计算并与大卫登可夫和佛兰克的方法进行对比,分析两种计算方法结果的异同点。采用室内模型试验和Midas/GTS/NX数值模拟对悬挂式帷幕基坑地下水渗流进行模拟,对公式推导的结果进行验证,证明文中提出的计算公式与实际情况更接近,并得出结论:基坑外最大水位降深随着帷幕插入深度的增加略有降低,但变化不大,基坑涌水量随着帷幕插入深度的增加逐渐减小。

In order to confirm relationship between flow rate of foundation pit and suspended curtain depth into stratum and relationship between maximum water level reduction of outside the foundation pit, so then finding the optimum value of sus- pended curtain depth into stratum, according to Darcy＇s law and large-well-method, formula was derived. By comparative analy- sis of example of derived formula and Davidenkoff＇ s way, the similarities and differences of the results was discovered. Ground- water seepage in foundation pit was simulated by laboratory model experiment and Midas/GTS/NX, verifying derived formula and coming to conclusion, which maximum water level reduction of outside the foundation pit was discussed slightly with in- creasing of suspended curtain depth into stratum and flow rate of foundation pit was reduced.