不同水灰比水泥净浆流变参数测定及注浆扩散特征

Rheological parameters measurement and grouting diffusion characteristics of cement slurry with different water cement ratios

为了探究不同水灰比水泥净浆的流变参数及注浆扩散特征,采用流变试验和数值模拟等方法,分析不同水灰比水泥净浆的流变性能及流变参数,研究宾汉姆流体在破碎岩体中的注浆扩散特征。研究结果表明:根据水灰比(b)水泥净浆可分为幂律流体(0.4≤b≤0.8)和宾汉姆流体(0.9≤b≤1.3),稠度系数、流变指数和浆液屈服应力随着水灰比的增大而降低;扩散半径与注浆压力、水灰比、裂隙开度分别呈幂函数、指数函数、线性增长关系,扩散范围为以注浆孔轴向为长轴、径向扩散半径为短轴的椭圆状;影响浆液扩散半径的主要因素依次为注浆压力、水灰比、裂隙开度。研究结果可为注浆工艺参数的确定提供参考。

In order to explore the rheological parameters and grouting diffusion characteristics of cement slurry with different water cement ratios,the methods of rheological tests and numerical simulation were used to analyze the rheological properties and rheological parameters of cement slurry with different water cement ratios,and the grouting diffusion characteristics of Bingham fluid in broken rock mass were studied.The results show that according to the water cement ratio(b),the cement slurry can be divided into power law fluid(0.4≤b≤0.8)and Bingham fluid(0.9≤b≤1.3).The consistency coefficient,rheological index and yield stress of slurry decrease with the increase of water cement ratio.The relationship between the diffusion radius and the grouting pressure,water cement ratio and fracture aperture are the power function,exponential function and linear growth,and the diffusion range is elliptic with the axial direction of grouting hole as the long axis and the radial diffusion radius as the short axis.The main factors affecting the slurry diffusion radius are successively the grouting pressure,water cement ratio and fracture aperture.The research results can provide reference for the determination of grouting technical parameters.