Abstract: The slurry-soil coupling effects have a great influence on the process of split grouting. The thickness of grouting vein has an attenuation from the region near grouting hole to the diffusion front. The process of split grouting is simplified into horizontal radiation circle. An equation for slurry motion in split channel is derived using the Newtonian fluid constitutive model. By introducing the force model of semi-infinite space, the governing equation for the thickness of grouting vein is derived. Finally, the spatial distribution equation for the grouting pressure and thickness of grouting vein is obtained. The spatial distribution response of the thickness of grouting vein and the grouting pressure is analyzed. The influence of slurry viscosity and elastic modulus of soil on process of split grouting is analyzed. The results show that the pressure attenuation trend in the radial direction is nonlinear, and that the change rate near the grouting hole and diffusion front is higher than that in other regions. The attenuation trend of thickness of grouting vein is similar to that of pressure. When the slurry viscosity and elastic modulus of soil are smaller, the grouting diffusion radius is larger. By comparing the theoretical model with the engineering example, the theoretical thickness of grouting vein is 1.3 times larger than that of the measured one.