Deep Mixing Method in Japan

Abstract

The Deep Mixing Method (DMM), a deep in-situ soil stabilization technique using cement and/or lime as a stabilizing agent, was developed in Japan and in the Nordic countries independently in 1970s. Due to its wide applicability and high improvement effect, the method has gained increased popularity in many countries. The method has been successfully employed in thousands of projects and the volume of improved soil from 1977 to 2010 exceeded 100 million cubic meters in the Japanese market alone. In the past three to four decades, traditional mechanical mixing has been improved to meet changing needs. Also new types of technologies have been introduced in the last 20 years and put into practice; e.g. high pressure injection and hybrid of mechanical and high pressure injection. The design procedures for various infrastructures were standardized by responsible organizations in Japan and revised several times. The manuscript presents a State of the Art on the Deep Mixing methods in Japan that covers the machinery, design, construction and quality control and assurance of the Deep Mixing Method.