高地下水渠道小井降水效果分析

高地下水位深挖方渠道施工中的降水问题,是影响水利工程输水干渠施工进度和效益的一个关键技术问题。本文以哈达山水利枢纽工程输水总干渠为研究对象,对低渗透性地层高地下水、深挖方渠道施工中的小井降水方案进行了试验研究,通过现场单井、双井和井群试验,提出了降水井的井径、井深、井距、降水时间以及抽水设备等参数,并研究了小井布局与结构、降水特性、降水方式和时间以及小井施工中的关键控制指标等,该试验的完成不仅能解决当前工程存在的问题,而且可以为类似工程的施工提供技术依据,并能推进低渗透性地层深井降水理论的发展。

Effect Analysis on Small Well Dewatering of Channel under High Groundwater Level

The precipitation problem in the construction of deeply excavated channel under high groundwater is a key technical problem affecting the construction progress and benefits of water conveying canal in hydro-engineerings.In this paper,the main water conveying canal of Hadashan Hydro Project is used as the research object to study the small well dewatering scheme of low-permeability layer in high groundwater and deeply excavated channel in construction by experiments. By site tests of single-well,double well and well group,the parameters such as well diameter,well depth,well spacing,precipitation time,pumping equipment and so on are proposed.Besides,the layout and structure of the small well,precipitation characteristics,precipitation patterns and time as well as the critical control indicators are studied in the experiments.The completion of the test can not only solve the problem existed in the current engineering,but also provide the technical basis for the construction of other similar projects and push the development of the theory for deep well precipitation in low-permeability layer.