为研究浆液与岩体的耦合作用机制，采用有限元方法对微裂隙岩体开展单一裂隙注浆数值计算。将连续性方程作为浆液流动的控制方程，将修改后的达西定律用于描述浆液在裂隙中的运动过程。基于弹性力学理论，提出考虑流固耦合效应的微裂隙岩体注浆扩散过程计算方法，研究裂隙开度、岩体弹性模量对注浆扩散距离的影响。研究结果表明： 1）在注浆过程中，裂隙开度由注浆孔附近向浆液扩散锋面处衰减，考虑流固耦合效应时注浆压力的计算误差能够减小30%左右，注浆扩散半径的计算误差可减小15%左右； 2）在注浆设计中应充分考虑流固耦合效应对注浆扩散过程的影响。

The finite element method is used to numerically simulate the grouting of microfractured rock mass, so as to study the coupling mechanism between grout and rock mass. And then the continuous formula is taken as the control formula for grout flow, and the modified Darcy′s law is used to describe the moving process of grout in fractured rock mass. Finally, based on elastic theory, the calculation method for grouting diffusion process in microfractured rock mass is proposed considering the effect of fluidsolid coupling, so as to study the influences of fracture opening and rock mass elastic modulus on grouting diffusion distance. The study results show that: (1) The fracture opening reduces from grouting hole surrounding to frontal surface of grout diffusion during grouting; and the calculation error of grouting pressure can be reduced by 30% and that of grouting diffusion radius can be reduced by 15% when considering the effect of fluidsolid coupling. (2) The influence of fluidsolid coupling on grouting diffusion should be fully considered during grouting design.