Point Foundation (PF) Method for Foundations and Embankments

Abstract

Conventionally, cement deep mixing (CDM) columns are designed to have constant diameters over the improved depth as this facilitates the construction procedures. However, in cases of spread footings or shallow foundations, this design pattern is less effective in term of stiffness distribution with depth. This paper first briefly introduces principles, construction procedures, and quality control methods of an improved CDM method that can create head-enlarged CDM columns (termed PF). The effectiveness of this improved method over the conventional CDM method in term of settlement reduction is then illustrated by a settlement analysis for an actual shallow footing. Analysis results from the case indicates that by using the same amount of soil-cement mixed volumes, settlement from a footing on PF columns can reduce up to 10 % compared with that from the same footing on CDM columns.