EFFECT OF PUMPING PROCEDURE ON MECHANISMS OF TGC GROUTING

This paper describes a physical modeling of the Thixotropic Gel Compaction (TGC) method using large-scale double-wall calibration chamber and injection systems. Results of injections performed with different pumping procedures (continuous and intermittent) and under different confining stresses are also presented. These results are discussed to evaluate the variation of grouting mechanisms in terms of the vertical displacement, volume change and lateral stress of soil with injection. It has been revealed that the method induces large vertical displacements and volume changes in the soil, as well as increases in the lateral stress. The initial stress state highly influences the mechanisms. The intermittent pumping is more effective than the continuous pumping in improving the soil. However, the pumping procedure does not have any appreciable effect on the increase of lateral stress.