Through FEM calculations

this paper discusses the influence of foundation rigidity and pile shafts on the bearing capacity of the composite ground of saturated loess and mucky soil with deep mixing cement piles under a flexible foundation. The results indicate that reducing foundation rigidity is beneficial to the bearing capacity of the soil between the piles

and that the degree of influence of pile shafts on the bearing capacity of saturated loess is larger than that of mucky soil. Finally

on the basis of the formula to calculate the bearing capacity of compound grounds reinforced with deep jet cement piles under a rigid foundation

two coefficients-foundation rigidity coefficient and soil bearing capacity coefficient are proposed according to the in-situ testing results and FEM calculation results; mean while

the value ranges of those new affecting coefficients are suggested. The formula proposed in this paper have been successfully applied in real projects.