基于地电场响应的多孔岩石注水-注浆模拟试验

采用大型有机玻璃模型对弱胶结多孔岩石注水-注浆过程中地电响应进行室内模拟试验研究。结果表明，自然电位和激励电流响应能很好地反映出试验过程的几个阶段。模型饱和前注水阶段，自然电位缓慢上升，激励电流发生小幅度跃升并稳定；模型饱和后继续注水，自然电位迅速升高到极大值并稳定，激励电流急剧跃升到极大值；停止注水后自然电位和激励电流都下降。注浆过程中，浆液渗流扩散区自然电位大幅度降低，而激励电流则迅速升高到较高数值；停止注浆后，浆液未到达区自然电位恢复到注浆前量值，而浆液充填良好区自然电位降到低于注浆前量值。综合注水-注浆过程中自然电位和激励电流的响应并与试验过程中摄取的数字图像对比分析可以得出，自然电位和激励电流对流体运动具有很好的“可视化”再现和指示流体渗流位置功能，尤其对水和化学浆液有良好的识别能力，用此可以反映注浆工程中浆液扩散情况及检验注浆效果。

Simulation test for water injection and grouting of porous rock based on response of electric field

Carried out water injection and grouting test of porous rock based on response of electric field by large Plexiglas model.It’s shown that variation of natural potential and exciting current well reflected the several stages of the test.Natural potential raised slowly but exciting current directly transited a stable value in water injection process before model saturation;however,they rapidly increased to the maximum after saturation and rapidly declined after stopping water injection.Natural potential was significantly reduced while exciting current fast increased in slurry flow diffusion zone.After stopping grouting,natural potential returned to the initial value in the area where slurry did not reached while dropped below the initial value in slurry spreading zone.It can be drawn that natural potential and exciting current have well function of visual representation and flow position indication to fluids,in particular,they well distinguish the water from chemical grout based on comprehensive analysis of these variation and digital image of slurry diffusion position.It can be used to monitor the slurry diffusion and evaluate grouting effects in actual projects.