A Research On Laws Between The Lift-Effect And The Mechanism Of Compaction Grouting

Ground lifting companied with compaction grouting has been regarded as a bad effect, which engineers try to avoid. But this effect is helpful to raise structure or the road back to near-original position. The author give a research on this effect firstly to utilize it, bring forward the notion/define of "grouting lifting-force" and "grouting lifting-effect", dissertate the feasibility of applying grouting to raise and underpinning the base of buildings, discuss the relation between the grouting mechanism and lift-effect. Although grouting-lift is a complicated dynamic process, according to the difference of action between the slurry and soil, this process is provided into several static stages in the paper. In every stage, the author expounds the working mechanism and builds the model, to study earth pressure distribution and lift-force magnitude when being grouted. The research indicates that the earth pressure is closely related to the grout pressure, grout depth and the soil character, and that it attenuates in the radial direction and upside. The study also results in the pattern of soil breakage, the maximum of grouting pressure, and relationship between the grouting effect and the grout quantity. Based on this theory, outdoor experiment has obtained good results. A large amount of experimental data about pressure and displacement show that the soil-pressure's distribution and the grout effect accord with theory on the whole. The experiment also proves that it is important that the position and order of grouting holes are arranged properly.