Research on the grouting plugging mechanism of layered jointed rock mass based on the time-varying yield stress of grout

Abstract The key to successfully treating water disasters with grouting is the diffusion range and the grout's ultimate efficient retention in the cracks; the gel qualities of the grout are crucial in this process of diffusion plugging. In earlier research, the time-varying viscosity of grout was given more attention than the yield stress, which is also subject to variation that grout must pass through to migrate. Groundwater migrates and stores through the interlayer opening fissure and vertical connecting fissure in the stratified jointed physical and chemical rock mass. The impact of plugging is only sometimes complete when the grouting is halted after filling the water-conducting crack. The grout will sink and cause grouting plugging faults and failure to meet water control criteria when its dead weight exceeds the yield stress in the vertical fissure. Studying how time-varying yield stress affects the grouting sealing mechanism during grouting is therefore crucial. This work introduces the notion of grouting diffusion decay and establishes a theoretical model based on the time-varying yield stress of grout. The steady pressure time during grouting is the key to ensuring the dispersion and ultimate retention of grout in the space range. The lowest stable pressure time for grouting and the change function for the height of decay are determined. A 3D visualization laboratory test instrument for grouting diffusion decay of layered jointed physical and chemical rock mass is constructed to confirm that the theoretical model is accurate. According to the research findings, the grouting duration can be reasonably planned, and efficiency can be increased while guaranteeing the grouting's sealing effect. This is crucial to developing the theoretical framework of grouting technology.