Grouting Effect on Reinforcement of Weathered Granite

In order to better understand the reinforcement effect of completely weathered granite, the influence of grouting pressure, water/cement ratio and sand/soil ratio were investigated based on the response surface method. The effect of these factors on the grout diffusion pattern and reinforcement effect were analyzed by fitting a response surface function. The results showed that, the factors that influenced the reinforcement effect are ranked from sand/soil ratio, grouting pressure and water/cement ratio. The sand/soil ratio had a significant effect on the grout diffusion pattern. Fracture-permeation, fracture-compaction, and fracture occurred successively with the varying of sand/soil ratios. The grouting pressure had a proportional relationship with the reinforcement effect, and the reinforcement increased initially and then decreased as the water/cement ratio ranged from 0.8 to 1.2. The equation of the relationship between the parameters and reinforcement effect was determined. A linear relationship was obtained between the uniaxial compressive strength and the disintegration time. The experimental results were verified by field test and can provide some guidance for grouting engineering in similar strata.