大志山注浆帷幕防治水工程大型抽水试验

Steady-flow pumping test of groundwater blockage by grouting curtain in Dazhishan mine

矿山帷幕注浆防治水工程具有典型隐蔽工程的特点,其施工质量检查鉴定和堵水效果评价一直没有可依照和遵循的标准,现有的单因素评价或多因素混合评价都难以给出定量结论,大型抽水试验是目前最为直接且有效的方法,但因工程复杂费用昂贵,很少使用.本文基于Dupuit稳定井流基本原理,在充分调查、分析矿区生产现状、水文地质条件、帷幕勘察、设计、施工资料的基础之上,设计并成功实施一大型抽水试验,使用单井抽水多个观测孔计算公式求解注浆后复合岩体的等效渗透系数,采用拟"大井法"对矿井深部的涌水量进行预测,其成果直接用于大志山帷幕注浆工程的质量检测与评价鉴定,取得较为满意的效果.

The grouting curtain, with the typical characteristics of underground engineering, has no specific standard to inspect its construction quality and evaluate the effect of grouting, and the quantitative conclusion is difficult to be given by single factor or multiple factors combination, so the large pumping test, which is rarely be implemented in practice because of its expensive and complicated characteristics,could be the most direct and effective method. Based on the basic principle of Dupuit's steady well flow, a large pumping test was designed and completed after the sufficient investigation and analysis of production status, hydrogeological conditions and grouting curtain document of investigation, design and construction about Dazhishan mine.In the test, the equivalent permeability coefficient of composite rock body after grouting curtain was solved by using single well pumping-multiple observation hole calculation formula, and the amount of water in deep was forecasted using 'virtual large diameter well' method, which was used in quality evaluation and appraisal in grouting curtain water plugging engineering in Dazhishan mine, and the results are satisfactory.