基坑工程管井回灌优化设计探讨

Study on Optimization Design of Tube Well Recharge for Foundation Pit

摘要:

目前基坑管井回灌设计及优化尚无专门成熟的方法，通过不同基坑回灌类型的分析，提出了基坑管井回灌设计原则及设计流程，并对回灌参数进行了探讨，对回灌可施加的最大压力进行了分析，通过285组基坑水文地质数值模型的计算，对比分析了不同渗透各向异性系数、回灌井结构、回灌井位置和保护建（构）筑物位置下的渗流特征，提出了回灌设计综合指数，从经济、技术及施工难度角度综合评估回灌对保护建（构）筑物以及对坑内降水的双重作用，指导抽灌一体化设计。

关键词:基坑工程;管井回灌;回灌渗流;悬挂式帷幕;单井回灌设计量;回灌设计综合指数;优化设计

Abstract:

Currently, there are no mature design and optimization methods of recharge for foundation pit tube well. Through the analysis on different types of deep foundation pit recharge, the design principle and process are presented and the discussion and analysis are made on the well recharge parameters and maximum recharge pressure. Based on the calculation of 285 sets of hydro-geological model of deep foundation pit, different permeability anisotropy parameters, recharge well types, well locations and seepage featrues under the buildings (structures) being protected are comparatively analyzed to provide the comprehensive index of recharge well design. From the angles of economic, technique and construction difficulty, the comprehensive evaluation are made on double effect of recharge to the buildings (structures) protection and pit dewatering to guide the integration design of pumping and recharging.

Key words:foundation pit engineering; tube well recharge; recharge seepage; hanging curtain; designed recharge flow of single well; comprehensive index of recharge well design; optimization design