PURPOSE: To prevent the generation of hazards caused by differential settlement, negative friction and others by burying a plurality of freezing pipes under the poor subsoil of a construction and, at the same time, detecting displacement occurred in the construction and forming freezing layers to control the displacement under the poor subsoil in the vicinity of the freezing pipes from the data.

CONSTITUTION: A plurality of freezing pipes 4... are buried under the poor subsoil 3 from the basement 2a of a building construction 2 and, at the same time, the displacement occurred in the construction 2 is detected, and the poor subsoil 3 in the vicinity of the freezing pipes 4... are respectively frozen and hardened to form freezing layers 5.... Vertical and horizontal displacement occurred in the construction 2 is effectively suppressed and controlled by taking advantage of rigidity of the freezing layers 5.... According to the constitution, deformation of the construction can be effectively suppressed.