Development of Strength Improving Technology for Cement-Stabilized Organic Soils

Where soft ground is widely distributed, ground improvement is necessary to ensure safety. Generally, as ground improvement, cement soil stabilization is applied for soft ground. However, cement soil stabilization may not be applicable to peat. This is because the humus contained in peat interferes with the hydration reaction of cement. There are some methods of using special stabilizers for peat, but it may not be possible to use it because the available place is limited or expensive. To solve this problem, the technology to improve strength of soil cement mixed peat was examined. When the cause of the strength decrease was examined, it was found that humic acid inhibited the hydration reaction of cement. Therefore, a cationic insolubilizing material was added so that humic acid did not adsorb on the surface of the cement. As a result, inhibition of hydrate by humic acid is suppressed, and the strength of soil cement with peat was improved. This result showed that cement stabilization of peat is possible using Ordinary Portland cement or slag cement even in places where stabilizers are not available.