高水压下车站基坑注浆堵水及施工效果评价分析

Evaluation and Analysis of Grouting and Water Blocking in Station Foundation Pit under High Water Pressure and Construction Effect

某车站基坑范围内,地质和水文条件极其复杂,砂卵石和板岩地层深厚、地下水丰富、地下水位高,且车站紧邻大桥,这给车站施工带来诸多难题。基于此,依托某地铁车站基坑工程,介绍了高水压下车站周边注浆堵水关键技术,并根据监测结果验证了关键技术的安全性与合理性。研究表明,针对砂卵石较厚,且地下水与水系相通的基坑,施工过程中需要对注浆量、注浆压力进行控制,及对注浆效果进行检验;基坑接头易渗水处可采取钢花管注浆和双重管法旋喷桩施工。研究结果可为类似工程施工提供借鉴与指导。

Station within the scope of geological and hydrological conditions are extremely complex, sandy pebble and SLATE formation, deep groundwater is connected with the river, underground water level is high, and the station next to the river bridge south approach, which bring many difficulties to the station construction. Based on this, relying on a subway station foundation pit project, this paper introduces the key technology of grouting water plugging around the station under high water pressure, and verifies the safety and rationality of the key technology according to the monitoring results. The results show that the grouting quantity and pressure should be controlled and the grouting effect should be checked for the foundation pit with thick sand and gravel and the groundwater is connected with the water system. The joints of the foundation pit joints can be constructed by steel flower pipe grouting and double pipe rotary jet grouting piles. The research results can provide reference and guidance for similar projects.