超大矩形深基坑潜水非完整井涌水量计算方法研究

Study on calculating the discharge of the partially penetrated wells in phreatic aquifer in rectangular deep excavation

针对基坑形状直接影响等效半径的取值,从而影响矩形基坑潜水非完整井涌水量计算结果的问题,提出了一种考虑宽长比的等效半径计算方法。在不同宽长比条件下,分别采用规范简化大井法和等效分段法计算矩形基坑的涌水量。结果表明:当基坑宽长比小于0.5时,采用考虑宽长比的规范简化大井法计算的涌水量大于采用未考虑宽长比的规范简化大井法计算的涌水量,基本等于采用不考虑宽长比的等效分段法计算的涌水量,十分接近工程实际抽水量。由此可知:采用考虑宽长比的规范简化大井法计算涌水量更为合理;采用等效分段法计算涌水量可忽略宽长比的影响。

This paper aims to solve the problems that the shape of the foundation pit affects the value of the equivalent radius and thus affects calculation the discharge of the partially penetrated wells in phreatic aquifer in rectangular excavation.A method of calculating the equivalent radius considering the width-length ratio is proposed.Under different width-length ratios,the simplified large-well method and the equivalent subsection method are used to calculate the water inflow respectively.The results show that when the width-length ratio of foundation pit is less than 0.5,the water inflow calculated by simplified large well method with the consideration of width-length ratio is larger than that calculated by the simplified large-well method without the consideration of width-length ratio,which is basically equal to the water inflow calculated by the equivalent subsection method without the consideration of width-length ratio,and is very close to the actual pumping water of the project.It can be seen that it is more reasonable to use the simplified large well method considering the width-length ratio to calculate the water inflow.The effect of width-length ratio can be ignored when the equivalent subsection method is used to calculate the water inflow.