Proposed minimum management strength to ensure INSEM hydration reaction

Joji SHIMA, Yoshikuni AKIYAMA and Takahisa MIZUYAMA

Target strength of sabo soil�]cement is set in accordance with the necessary strength for facilities and parts. However, this does not guarantee the appearance of hydration reaction desirable for the target strength for INSEM material. INSEM method is one of the sabo soil�]cement methods. In order for INSEM material to have a hydration reaction, addition of water is being practiced based on the optimum moisture content. Adding water is necessary when adding cement, because there is not enough amount of water in the amount provided with the optimum moisture content. With the fact in mind, we have conducted a study on the strength range to acquire stable strength of INSEM material. As a result, it is concluded that the minimum amount of cement and the minimum compression strength are required in order to strengthen the whole material by hydration reaction. The minimum unit of cement amount depends on each material; however, the minimum management strength was about the same value as 2.0/mm2. Aiming to produce INSEM material using stable strength quality, we need to set the target strength higher than the minimum management strength value which enables us to recognize the hardening at the point of its appearance through the hydration reaction. Our management of material with the assessed values makes it possible for us to produce the rational and reliable INSEM material.