【摘要】 为精准探测超深基坑地下连续墙接缝渗漏缺陷提出了温度示踪测试方法。该方法是在基坑外侧紧挨超深基坑地下连续墙接缝处打设与混凝土地下连续墙同深度的钻孔，然后在基坑抽水前后分别测试钻孔内不同深度地下水温度，获得地下水温度垂向分布曲线，再根据温度曲线垂向标准形态和由于渗漏造成的温度曲线异常精准判断接缝渗漏位置深度。2个代表性超深盾构井基坑混凝土地下连续墙接缝渗漏探测分析结果表明，精准判定的渗漏缺陷位置都得到了基坑开挖和基坑排水量两个方面直接和间接验证。得出了超深基坑防渗结构体渗漏缺陷引起的地下水垂向温度曲线局部变化恰好是判断渗漏缺陷深度位置的重要依据，且因渗漏处温度变化十分微弱，捕捉微弱温度异常的温度测井仪分辨率和稳定性十分重要。更多还原

【Abstract】 A temperature tracer testing method was proposed to accurately detect leakage defects at the joints of underground diaphragm walls in ultra-deep foundation pits. This method involved drilling holes immediately outside the joints of the underground diaphragm walls of the ultra-deep foundation pit to the same depth as the concrete underground diaphragm wall, and then measuring the groundwater temperatures at different depths inside the holes before and after pumping water from the foundation pit, to obtain the vertical distribution curve of groundwater temperature. Based on the standard vertical pattern of the temperature curve and its anomalies induced by leakage, the leakage depth at the joint was accurately determined. The leakage detection analysis results of the joints of the concrete underground diaphragm wall in two representative ultra-deep shield shaft foundation pits showed that the accurately identified leakage defect locations were directly and indirectly verified by both the excavation process and pumped-water volume of the foundation pit. The local changes in the vertical temperature curve of groundwater caused by leakage defects in the seepage-control structure of ultra-deep foundation pits are an important basis for determining the depth of leakage defects. Moreover, due to the very weak temperature changes at the leakage site, the resolution and stability of temperature logging instruments that capture weak temperature anomalies are crucial.更多还原