Many tide breakwaters had been damaged by the impact of a tsunami that occurred due to the Great Tohoku Earthquake in 2011. As a restoration works, a tide breakwater with the length of about 800m and the height of T.P. +14.5m is being constructed in the coast of Katagishi in Iwate prefecture. In which, a special deep-mixing method with large diameter and great depth (DCS method) was applied to the ground that is sandwiched by hard soil layers in order to construct foundation of the tide breakwater. In addition, a real-time contrition management and work completion progress/quality control system is introduced in this paper. As examples of the result obtained in this paper, it was confirmed that the deep-mixing method with the diameter of φ = 2.0 m and the depth of 33.6 m can be performed by applying the DCS method. The introduction of the real-time construction management and work completion progress/quality control system enabled it to ensure shape and quality of improved soil with high accuracy and it was confirmed that information sharing is promptly possible.
