对称式基坑渗流涌水量的计算方法

随着地铁、越江隧道等地下工程的日益增多,涌现出了大量的对称式基坑。基于共形映射理论,推导了对称式基坑涌水量计算表达式,并对其计算参数进行分析。研究表明,对称式基坑的单宽涌水量与渗透系数、基坑内外水头差成正比,与(相对)隔水层层顶到坑底的距离和基坑两侧止水帷幕间距的比值、止水帷幕嵌固深度和(相对)隔水层层顶到坑底距离的比值、基坑内外水头差和(相对)隔水层层顶到坑底距离的比值成反相关。

Calculation Method of seepage discharge for symmetric foundation pits

In recent years,with the development of crossing-river tunnels and subways,there are more and more symmetric foundation pits.Based on conformal mapping,the mathematical modeling is built and the expression of seepage discharge in pensile curtain foundation pit is deduced,then calculation parameters of seepage discharge are analyzed.The results showed that the seepage discharge of symmetric foundation pit has direct ratio with permeability coefficient and the water head between the outside and inside of foundation pit.And the seepage discharge of symmetric foundation pit is in inverse correlation to the ratio of the distance between the top of relative impermeable layer to the bottom of foundation pit and the distance between pensile curtains,to the ratio of the embedded depth of pensile curtain and the distance between the top of relative impermeable layer to the bottom of foundation pit,and to the ratio of water head between the outside and inside of foundation pit and the distance between the top of relative impermeable layer to the bottom of foundation pit.