Study on Microscopic Roadbed Grouting Mechanism Based on CFD-DEM Coupling Algorithm

Abstract

Grouting reinforcement technology gradually has been widely used to repair the subgrade settlement diseases, but the current single application of discrete element software or finite element software cannot effectively simulate the grouting process. Therefore, one new method is put forward in the research of grouting based on the CFD-DEM coupling principle. And then, one typical subgrade section in the Shanghai–Nanjing intercity railway is used to simulate the grouting process and diffusion mechanism of slurry from microlevel. Based on the results of site survey, some findings are shown as follows: First, the new method is feasible which integrates the favorable aspects of discrete elements, finite elements, and boundary elements. Second, the greater the grouting pressure, the greater the influence range of grouting, and it shows six petals shape. When the grouting pressure is small, the grouting generally shows penetration or extrusion grouting, and its influence range is small. When the grouting pressure is large enough, it is characterized by splitting grouting, and the influence range of grouting is getting larger and larger. Third, the growth rates of influence range gradually increase with the increasement of grouting pressures, and the reasonable selection of grouting pressures is very important.

Numerical investigation of slurry property effect on grouting and blocking of flowing water in rock fractures

“…The microscopic grouting process is studied by coupling FVM and DEM. 37,38 Chen et al developed a hybrid finite element method coupled with VOF method to simulate the fracture grouting processes in soils. 39 In previous studies, the assumption of slurry viscosity is usually constant or power function, only the temporal variation of slurry viscosity is considered, and the unified viscosity field is used.…”

“…Scholars have also carried out further research by combining various discrete methods with FVM. The microscopic grouting process is studied by coupling FVM and DEM 37,38 . Chen et al.…”

Research on Deformation Mechanisms of a High Geostress Soft Rock Roadway and Double-Shell Grouting Technology

“…Zhang et al proposed a grouting material with low cost and high density for the reinforcement of large-scale floor cracks; the optimal proportion of constituents for the new grouting material (including 1% foaming agent) was 40% of cement, 30% of clay, and 30% of fly ash [14]. Yang et al put forward a new grouting method based on the CFD-DEM coupling principle; one typical subgrade section in the Shanghai-Nanjing intercity railway was used to simulate the grouting process and the diffusion mechanism of the slurry at the microlevel [15].…”