Evaluation of effect of insertion of casing by rotation on existing piles

Various issues have been encountered in the removal work of existing piles, such as existing piles being left in the ground, the subsidence of the surrounding ground and the deterioration of the ground environment when reusing the site. However, there are no regulations for the filling material to be injected into the draw holes that form after the removal of existing piles or for the removal work itself. In this study, therefore, in order to evaluate the effect of the insertion by rotation of the casing onto an existing pile as part of the work to remove existing piles, the effect of the stress loaded onto an existing pile when the casing is inserted into the ground using moving-particle semi-implicit–computer-aided engineering and the mechanism of its occurrence are clarified. As a result, it is found that the inner diameter of the casing used, the value of the plastic viscosity of the drilling fluid and the mechanism by which the stress is loaded onto an existing pile can be evaluated such that the destruction of the existing piles can be avoided.