To explore the characteristics of the seepage grouting process of fractured rock
this study designed a set of rock fracture grouting experimental systems
including slurry supply
data monitoring
and grouting simulation sub-systems. Through the grouting experiment of single fracture sandstone under different grouting pressures (0.3
0.4
0.5 MPa)
the variation of pipeline flow pressure
slurry flow rate
and slurry pressure were analyzed
and the influence of slurry parameters on flow characteristics was discussed by numerical simulation. The experimental results show that the pipeline flow pressure
slurry flow rate
and slurry pressure show a three-stage characteristic of rising-stabilizing-falling. In the stable stage
the three variables positively correlate with the grouting pressure
but the sensitivity to the change in grouting pressure is different. With the increase of grouting pressure
the slurry pressure increases
while the response of slurry flow to the change of grouting pressure gradually decreases (when the grouting pressure increases from 0.3 MPa to 0.5 MPa
the slurry flow increases by 15.3% and 8.1% respectively). When the grouting pressure reaches 0.3 MPa
the flow pressure in the pipeline remains unchanged. The numerical simulation results show that the slurry flow is related to its diffusion form in the fracture. When the diffusion is semi-circular
the slurry velocity decreases
and the flow rate increases. The slurry velocity increases when the diffusion form changes from semicircle to convex. When the diffusion form changes from convex to uniform diffusion
the parameters tend to be stable. The slurry flow rate and flow velocity are inversely proportional to the plastic viscosity of the slurry. The increase of the plastic viscosity enhances the effect
while the slurry yield stress has little effect on the flow rate and flow velocity.