Abstract
Groundwater is widely distributed in various rock and soil media and underground structures. Groundwater seepage inside the silty-fine sand layer causes infiltration erosion, leading to uneven settlement and cracking damage to the foundation and its structures. An analysis was conducted on the mechanisms of flowing soil and piping, and it was pointed out that flowing soil is caused by the effective gravity of sand particles, resulting in the floating and failure of sand particle groups due to the permeability greater than that of sand particles; Pipe surge refers to the migration and loss of movable fine particles, and the formation of water inflow channels through the interior of the silty-fine sand layer. Propose technical measures to improve the physical and mechanical properties of silty-fine sand layers and prevent infiltration damage through grouting. The mechanism of infiltration, splitting and compaction grouting was explained and analyzed, and the grouting materials such as plant glue modified cement sodium silicate, geopolymer, microbial solution, nano silica sol, emulsified asphalt, polyurethane, etc. were discussed and sorted out, aiming to contribute to improving the quality of silty-fine sand layer engineering projects.