速凝浆液岩体倾斜裂隙注浆扩散模型研究

Grouting Diffusion Model of Quick Setting Slurry in Dip Crack Rock Masses

针对以往渗透注浆扩散模型常以水平平板裂隙面为前提,未考虑岩体裂隙面产状对注浆扩散机制的影响问题,选取工程地质灾害处理中常用的水泥-水玻璃双浆液(C S浆液)为速凝类注浆材料,将C S浆液流型看成是具有黏度时变性的宾汉流体进行分析。基于流体力学理论及粗糙裂隙等效水力开度的确定方法,同时考虑了浆液自重作用的影响,建立了恒速率注浆条件下反映浆液黏度时空变化的倾斜裂隙注浆扩散模型。在此基础上,推导了浆液扩散区内的黏度及压力时空分布方程,定量确定了注浆压力与注浆时间及浆液扩散距离的关系。最后,借助于室内试验和有限元分析程序,研究了恒速率注浆时不同裂隙面产状下的浆液扩散规律,并将数值模拟结果与理论计算值进行对比,进一步验证了所建立的注浆扩散模型的有效性和合理性。研究成果可为注浆工程速凝类浆液注浆参数的确定提供借鉴。

With horizontal cracks as the premise,conventional models of penetrative grouting diffusion do not reflect the impact of the occurrence of rock mass cracks on the grouting diffusion mechanism.In view of this,a theoretical diffusion model of grouting in dip cracks at constant grouting rate was established in consideration of the uneven spatial distribution of viscosity based on the theory of fluid mechanics and equivalent hydraulic aperture of rough walled cracks.Quick setting double slurry(cement-sodium silicate slurry),commonly used in engineering geological hazard treatment,was regarded as Bingham liquid with time-dependent behavior of viscosity in static water environment and was chosen as the grouting material.The dead-weight of grouting slurry itself was taken into consideration,Furthermore,the space-time distribution equation of viscosity and pressure in the diffusion region of slurry was derived.And the relations of grouting pressure versus grouting time and grouting diffusion distance were quantitatively determined.Finally,the slurry diffusion characteristics in the presence of different occurrence of cracks at constant grouting rate was studied by means of laboratory tests and finite element analysis procedures.Comparison between numerical simulation results and theoretical calculations verified the validity and rationality of the theoretical model.The results may be constructive to the determination of grouting parameters of quick setting slurry in practical engineering.