Bases on theory of plasticity and the large strain

the early phase of fracture grouting is regarded as the question of cavity expansion in infinite soil. The stress distribution due to the cavity expansion in soil is considered as two zones. The deformation following little deformation in elastic zone and large-deformation in plastic zone is taken into consideration. By using the theory of cavity expansion

hydro-fracture and pore water pressure theory

on the assumption that the sum of initialization stress of soil and increment due to cavity expansion is equal to the pull strength of soil

the soil is fractured by grouting. If the large and small stress of soil is conversion

the second fracture grouting takes place. Based on the above theory

the fracture grouting pressure in saturated soil is given. According to the comparison

the result of the present theory is very near to the those of the engineering practice.