Investigation of Injection pressure during compaction grouting

Abstract

This research presents the results of compaction grouting tests to investigate the effects of injection depth and injection rate on cavity shape and expansion. The one-stage injection tests use real compaction grout injected into a dry, cohesionless soil. The soil response due to injection is evaluated with respect to the injection pressure during grouting and the degree of compaction in the surrounding soil. The results of the experimental program have previously shown that the final shape and volume of the grout bulb and the minimum overburden above which compaction grouting is no longer efficient is dependent primarily on injection depth and grout composition, and to a lesser degree, injection rate, and soil type. The results of this phase of research show that the overburden pressure and injection rate have an effect on the pressure required to initiate and sustain cavity expansion and grout bulb development.