上海第⑨层承压水的短滤管减压井试验研究

Experimental Study on Short Filter Tube Relief Well for Confi ned Water in the 9th Layer of Shanghai

上海第二、第三承压水降水及其导致的环境沉降是目前深层地下空间开发中的技术难点,采用短滤管减压井可以增加滤管底与截水帷幕底之间的高差,有助于控制坑外降深和沉降。在上海张江硬X射线工程现场,采用气举反循环工艺成井,进行了不同滤管长度减压试验井的现场抽水试验,对不同滤管长度下减压试验井产生的第二、第三承压含水层的降深进行比较。试验表明,短滤管减压井能较好地控制第三承压含水层降深。试验成果得到了设计采用,对类似工程设计具有一定的指导意义。

The dewatering of the second and third confined water in Shanghai and its environmental settlement caused by it are the technical difficulties in the development of deep underground space at present.The use of short filter tube relief well can increase the height difference between the bottom of filter pipe and the bottom of water cut-off curtain,which is helpful to control the drawdown and settlement outside the pit.At the site of Zhangjiang hard X-ray project in Shanghai,the gas lift reverse circulation technology was used to complete the well,the field pumping tests of pressure reducing test wells with different filter tube lengths were carried out,and the drawdown of the second and third confined aquifers produced by the decompression test wells with different filter tube lengths were compared.The tests show that the short filter tube relief well can control the drawdown of the third confined aquifer.The test results have been used in the design,which has a certain guiding significance for similar engineering design.