Lateral radiation grouting technique is a new technology to treat the settlement of existing expressway by reinforcing ground while in operation.Grout casting effect needs to be analyzed to ensure traffic safety.Based on the spherical expansion theory for soil

a multiple spherical cavities expansion model was established to assume the grouting process as the half-space spherical cavity expansion.By simplifying the complex geometric condition of lateral radiation grouting as spherical expansion of multiple cavities

and by introducing the theory of spherical expansion to obtain the relation between grouting pressure and expansion radius

the conclusion was obtained that limit grouting pressure exists and softening effect can be found when grouting pressure reachs the limit.Then a method considering both grouting pressure and grouting volume was given to calculate the ground heave due to grouting.According to the field test data

calculation result was compared with the analyzed ground heave with different grouting pressure and grouting gaps.A calculation method for ground heave due to lateral radiation grouting was proposed to provide guidance for grouting design and construction.