基于目标函数法的基坑降水最优化模型求解与应用

Optimization Model Solution and Application Research of Foundation Pit Dewatering Based on Objective Function Method

为优化基坑降水总涌水量,求取各降水井的最优单井抽水量与最优降水井数,建立了基于目标函数法的基坑降水最优化模型。以河南省西霞院水利枢纽输水及灌区工程渠首倒虹吸段基坑降水工程为例,运用目标函数法建立了倒虹吸段基坑降水最优化模型,调用MATLAB优化工具箱对工程实例的倒虹吸段基坑降水模型进行优化求解,并采用GMS数值模拟软件对优化结果进行验证分析。优化与模拟结果表明:在满足基坑施工要求、保证周围环境安全的条件下,采用Fmincon函数和GA遗传算法优化结果分别比原抽排计划(3个月)减少总涌水量624300 m^(3)和546390 m^(3),对单井抽水量和井的数量方面也能进行合理优化。因此,采用目标函数法调用优化工具箱进行基坑降水优化设计是可行的,能取得很好的优化效果。

In order to optimize the total water inflow of foundation pit dewatering,obtain the optimal single well water yield and the optimal number of dewatering wells,an optimization model of foundation pit dewatering based on objective function method was established in this pa⁃per.Meanwhile,taking the headwork inverted siphon foundation pit dewatering project of Xixiayuan Water Conservancy and Irrigation Area Project in Henan Province as an example,the optimization model of canal foundation pit dewatering in inverted siphon section was established by using the objective function method,and MATLAB optimization toolbox was used to optimize the solution of the canal foundation pit dewa⁃tering model of the project example,and GMS numerical simulation software was used to verify and analyze the optimization results.The opti⁃mization results show that:under the condition of meeting the construction requirements of the foundation pit and the safety conditions of the surrounding environment,compared with the initial scheme,the total water yield can be reduced by 624300 m^(3) and 546390 m^(3) respectively according to the pumping and drainage plan by using the Fmincon function and Genetic Algorithm,and the single well pumping capacity and number of wells can also be optimized more reasonably.Therefore,it is feasible to use the objective function method to call the optimization toolbox to optimize the design of foundation pit dewatering and can achieve good optimization effect.