The working mechanism of reinforced soil-cement mixing diaphragm wall has been analyzed. It is pointed out that the strength of soil-cement must be enough in the reinforced soil-cement mixing diaphragm wall. The strength of soil-cement between the shaped steels must be enough not only to load the shear stress

but also to load inclined section stress along the level. Although the contribution of soil-cement to vertical bending rigidity of the wall is too little to neglect

the compression strength of soil-cement must be enough to be kept integrity and water stop. On the other hand

the side restriction of soil-cement to shaped steels must be strong enough and be kept integrity to keep integral stability of shaped steels.