A DETAILED STUDY FOR THE HYBRID APPLICATION OF DEEP MIXING COLUMNS COMBINED WITH WALLS BASED ON THREE DIMENSIONAL FEM ANALYSIS

Abstract

 The hybrid application of deep mixing Columns with walls featuring a new three-dimensional improvement form, based on the combined use of wall-type and pile-type improvements, was developed for application in foundations of high embankments on soft, viscous ground. Compared to conventional methods, this method is advantageous in that it is highly effective in controlling changes in the ground surrounding embankments. To reflect the effects of three-dimensional improvement forms on design, a detailed study using three-dimensional FEM analysis, not generally used for ground improvement design, is conducted. This study reveals that the maximum benefits in control of change can be achieved by locating a wall-type improvement at the top of an embankment slope via three-dimensional FEM analysis using the MuDIAN analysis code. This method is therefore more economical than conventional pile-type improvement. Proof is also given of the ability to use the method for detailed study through simulation of trial works on the Kumamoto Udo Road designed using FEM analysis.