Grouting diffusion mechanisms is sand based on DEM
Fu Yanbin1，3 Zeng Deqi1 Li Daimao2 Lu Andian2 Qiao Guolong2 Xiong Hao1,3
1. College of civil and Transportation Engineering, Shenzhen University, Shenzhen 518060 China；
2. Guangdong GDH Pearl River Delta Water Supply Co. , Ltd. , Guangzhou 511458 China；
3. Key Laboratory of Coastal Urban Resilient Infrastructures (MOE), Shenzhen University，Shenzhen 518060 China
Abstract：To investigate the macro and microscopic interaction mechanism between slurry and sand particles during the grouting process, discrete element method (DEM) is employed. A sand sample is prepared by compacting gap-graded particles. The effects of diffusion mode, diffusion range and soil strength are analyzed by varying different grouting velocities, as well as the reasons for the surge of grouting pressure. The numerical results show that the diffusion rate gradually slows down and the strength of the soil continues to increase as the slurry particles continues to be injected. As the grouting velocity decreases, the diffusion range of the slurry increases. The moment when grouting pressure surge completely coincides with the contact time of injecting boundary and sand particles, which explains the reason for the sudden increase of grouting pressure. Moreover, the mechanism of the grouting pipe blockage caused by the sand particles back pouring into the grouting pipe in actual engineering is revealed.
