Research of effective parameters to strengthen soil foundations by cement-sand mixture injection method

摘要

High pressure direct injection of high-flow cement and sand mix method is a promising means of soil base consolidation. The method features the injection of cement and sand mix into the ground base under pressure, exceeding the ground structural strength. This causes the continuity of the soil body to break and the void is filled with mortar, which gets solid, forming the solid incompressible inclusions, reinforcing the ground base. The indirect effect is the soil compacting around these inclusions, which is also good for the ground strength. The advantages of this method are the ability to work in highly confined area, no need for expensive equipment and low budget. The method is adapted for the solution of the following geotechnical problems: ground base reinforcement, reinforcement of existing buildings foundations while building nearby structures; reinforcement of shallow foundations under worse geotechnical conditions or their reconstruction; straightening of buildings on raft foundation structures, in the process of construction and through the first years of operation; better bearing capability of piled foundations; reinforcement of foundations with dynamic loads.The article features the results of the set of laboratory and semi-natural experiments on effective parameters of ground base strengthening: ground strengthening scheme, spacing between inclusions, the volume and distance between the injection horizons, effective size and volume of inclusions.