Optimization of multi-well dewatering based on objective function for a subway tunnel

Multi-well dewatering for a subway tunnel is optimized using the Excel software based on optimal objective function and with the primary constraint conditions of groundwater level at the controlling points and the target function of minimum drainage flow.The influenced range of dewater,locating project of dewater well and drainage of a single well are obtained,and the target of minimum drainage flow is also obtained.Dewatering in the Zhangshen tunnel is analyzed with the optimization method.The influenced range of dewatering and the optimized drainage(18 552.6)m~3/d is reduced by 5%,lower than the result calculated with the model of a fully penetrating well in an unconfined aquifer.The dewatering curve is obtained and compared with the simulated finite element analyses and the optimal design is confirmed to be reasonable.