The ground freezing method is one of effective ground improvement methods with high applicability and reliability. However, the method may cause some problems to the surrounding ground and structures due to by ground swelling at freezing and ground subsidence at thawing. Consequently, this method requires an adequate management in controlling its effect to surrounding environment. It is therefore important to understand the correlation between the ground condition at freezing and thawing and the behavior of surrounding ground based on some case histories. This paper deals with the field data on a construction work using the ground freezing method in soft clay ground. Examined are the ground displacement of the unfrozen ground adjacent to freezing front caused by the growth of freezing ground and the behavior of earth and water pressures based on the data. Furthermore, the behavior of earth pressure at freezing is compared with that on the excavation-side wall in the earth retaining excavation work. As the results, the correlation between mobilization of passive earth pressure and ground displacement is elucidated.
Urbanization is very intense in Japanese large cities like Tokyo and Osaka. The excavation work is therefore to be performed close to urban facilities for development in deeper underground space. Consequently, it is necessary to control the effect of the construction work to the surrounding ground. Accordingly, applicable excavation and earth retaining methods are sometimes limited. To control the effect to the surrounding ground, it is necessary to examine various countermeasures and evaluate their effects. In the case of earth retaining excavation work, the countermeasures are to increase the stiffness of earth retaining wall and strut, to devise the shape of excavation surface, to perform the excavation in each divided block, or to improve the ground around excavation or at bottom ground.