Abstract：The strain distribution around the cylindrical cavity is classified into plastic zone and elastic zone. The theories of small deformation and large deformation are adopted in the elastic zone and plastic zone respectively. According to the stress equilibrium equation and conditions of stress and strain，the stress distribution in two zones，radius of the plastic，limited cavity expansion pressure and excess pore pressure are obtained considering large deformation and undrained conditions. The results agree well with those of the in-situ test，which proves that the proposed theory has certain reference value. The calculations show that with the increase of parameter b，the limited cavity expansion pressure increases nonlinearly while the excess pore water pressure is on the contrary.
