【摘要】 首先分析了变态混凝土混合物(MC)的特性,认为碾压混凝土拌合物(RCC)可视作各向同性、孔隙分布均匀的多孔介质,MC浆液可视为幂律型流体.通过仿真发现在重力作用下,MC浆液在RCC中的渗透近似柱形扩散.因此基于柱形扩散理论,假设浆液渗透流动为层流,建立了变态混凝土施工中的注浆模型.运用渗流力学基本定律,推导出浆液扩散半径与注浆压力、渗透系数、稠度系数、流变指数、注浆管半径、注浆时间和孔隙率之间的关系.通过因子分析,研究了各参数对浆液扩散半径的影响,结果表明:注浆压力、流变指数对扩散半径的影响最大,渗透系数的影响次之,稠度系数和孔隙率的影响相对较小.本研究为多管插入式压力注浆施工方法提供了理论依据.更多还原

【Abstract】 Through analyzing the characteristics of metamorphic concrete(MC),it is recognized that the roller compacted concrete(RCC) can be regarded as an isotropic porous media with evenly distributed pore and MC grout as an exponential fluid.According to simulation results,it is found that,under the effect of gravity,MC grout was permeated through RCC in cylindrical diffusion mode.Therefore,based on the cylindrical diffusion theory and the assumption of laminar flow of MC grout,a grouting model for MC construction is established.The relationships among diffusion radius of grout and grouting pressure,effective permeability of RCC,effective viscosity of grout,rheological index of grout,radius of grout pipe,permeation time of grout,porosity of RCC,are deduced according to this model and basic law of fluid mechanics in porous media.The influences of various parameters on the grout diffusion radius are researched based on factor analysis; and it is found that the grouting pressure and rheological index of grout have most important affect on diffusion radius of grout; while the permeability of RCC is less; the viscosity of grout and porosity of RCC are least.The results provide a theoretical basis for a multi-tube and plug-in pressure grouting construction method.更多还原