Abstract：
Beｃause of freezing method is impermeable and other obvious characteristics, it is more and more used in underground constructions, especially in water bearing ground. But sometimes the frozen wall has permeable “window” because the groundwater is too fast. In order to locating the permeable “window” we can encrypt the measuring point in thermometer holes. Then we can analyse the reason and take the specific measures. Pluging the water channel by ground grouting, quick freezing with liquid nitrogen shows obvious effect. We achieved the desired effect by such measures in the project of Tianjin Metro Line3 North Jiefang Road station.
