Application of cement-mixed gravel reinforced by geogrid for soft ground improvement

The strength of gravel increased dramatically by adding a little amount of cement and equivalent to that of concrete materials. So, the cement-mixed gravel is expected to be effective to be used as bending member. In this paper, we have described the bending member tests as conducted to investigate the bending deformation characteristics and evaluate the reinforcement by geogrid. It revealed that the peak strength of the cement-mixed gravel did not decrease when the specimen reinforced by geogrid. We proposed slab for ground improvement on soft ground additionally, as the application of bending members. Usually, on soft ground, ground-improvement piles used for the support of embankment is often excessive because of the limitation of the deformation between the piles. Therefore, the ratio of the improvement piles could be reduced by using the slab between soil structure and piles. The efficiency was evaluated by conducting shaking table tests of liquefiable soft ground. In the case of using this slab, the deformation of soft ground and embankment was less, so the efficiency of this method was satisfactorily proven.