A case study, on the reduction of settlement caused by compaction grouting system

In this study the Compaction Grouting System (CGS) as an injection method by using the low slump mortar was performed to reduce the settlement in an apartment complex experiencing excessive settlement than expected. Field and lab tests were carried out to evaluate the effects and applicability of CGS. From the results of the tests, CGS method was optimized by the control of diagram, space, depth, injection materials and pressure. CGS improves soft ground compositely by the bearing effect of CGS columns and reinforcement of adjacent ground. Considering that the increase of N value is about 3, CGS can be considered as an effective method to increase the bearing capacity as well as to stop the settlement of soft ground. It is also expected to be economic and effective on improvement of ground when it is used in the applicable sites.