Abstract：
As an auxiliary measure of shallow burying subsurface excavation construction, deep-hole grouting in sand gravel stratum covered with shallow soil often cause land upheaval. During subsurface excavation of a Beijing subway station project, the reason for land upheaval during deep hole grouting was analyzed. It was proposed that grouting pressure, grouting sequence, mortar proportion and monitoring shall be key control points when deep hole grouting method was used for strengthen sand gravel stratum. Relevant measures shall be adopted in advance to guarantee the deep hole grouting effect and avoid land upheaval.
