Proposal of Constructional Countermeasures for the Widening of Embankments with a Focus on Their High Stability

The improvement rate of countermeasures adopted in constructing a second track on an embankment on soft ground is determined empirically due to unknown factors such as the deformation properties of soft ground. In this study, centrifuge model tests were performed to grasp the deformation properties of soft ground for such construction cases. Based on the test result, a new countermeasure was proposed, which has high horizontal support performance and combines deep mixing wall-type ground improvements and cement-mixed gravel. The proposed method having the same improvement rate as deep mixing was confirmed as being able to reduce the deformation of the embankment and the surrounding ground.