feasibility and crisis of cement deep mixing piles are introduced. The mixing inhomogeneity and discontinuity along pile length in the present construction quality are pointed out. The reasons resulting in quality problem are analyzed as 3 aspects
i.e. severely delayed quality inspecting methods in the code
irrationality of construction techniques
disordered construction supervision. Then 3 kinds of countermeasures and 9 kinds of innovative approaches in construction techniques are put forward.