Grouting experiment in a completely weathered granite dam abutment: case study on grouting technique and test analysis

Anti-seepage grouting of earth-rock dams is an important aspect of dam construction projects. Completely weathered granite is a typical porous granular soil. Traditional grouting techniques cannot meet the requirements of completely weathered granite grouting. Therefore, pulsating grouting, which combines drilling and grouting, is proposed, and grouting experiments were performed on a completely weathered granite reservoir abutment in combination with traditional clay–cement slurry materials. The results show that single row, 1 m hole spacing of the permeability after grouting was less than 10 Lu. The acoustic wave velocity increased by 17.3–52.5%. Moreover, the core sample was relatively complete, and the compressive strength of the core reached 7.3 MPa on average. The proposed technique significantly reduces the unit cost is applicable to completely and strongly weathered granite and similar formations. Thus, this work provides an engineering reference for these formations.