Abstract:

Laterite is a kind of special soil which was formed by the laterization in the condition of hot and humid climate with the characteristics of high moisture content, large void ratio, higher strength and lower compressibility. As its special engineering geological properties there will be a larger settlement after construction on the foundation of red soil. Nowadays, the dynamic compaction as a method of ground treatment is widely applied and the deformation of laterite foundation after construction is always studied by field monitoring combined with laboratory test. The main factors which affect the compaction effect and the compaction characteristics of the laterite after compaction are deeply discussed on the base of the compaction test and consolidation test in the laboratory. And the mechanism analysis of factors are made. The experimental results show that the compaction effect has related with the content of clay, the plastic index, the free iron oxide and the compaction effort. The more content of clay, the higher plastic index and the more content of the free iron oxide would lead the worse compaction effect. The compaction effect is also in proportion to the compaction effort. The compression modulus of laterite after compaction is affected differently by the factors such as moisture content, dry density and degree of saturation. When the moisture content of the laterite is greater than 18% and the degree of saturation is close to 100%. The moisture content and dry density can’t reflect the compaction characteristics. Hence, in practical engineering the moisture content of the laterite shuold not be greater than 18% to avoid the larger settlement.

Key words: laterite, compaction characteristics, dynamic compaction, degree of saturation, Guangxi Province