Relationship between consistency and compaction of clay soils (Saint-Petersburg)

Abstract

Clay soils are often found under building foundations, construction properties of which depend on many factors. One of them is the natural soil compaction, which is relevant in the construction classification of soils. This paper analyzes the relationship between the consistency and compaction of clay soils of different genesis and consistency using the Priklonskii soil compaction index. Water saturation of clay soil affects the relative discrepancy between the consistency coefficient and compaction index for soils of different genesis and consistency. It is noted that for soils with the water saturation coefficient lower than one, the consistency coefficient differs from the compaction index. This difference increases with decreasing water saturation coefficient. It is essential that significant differences can also appear when the water saturation coefficient is equal to 0.95 or more, approaching to unity. It is shown that the assessment of the natural compaction of clay soils should be based on their formation conditions. A study of various genetic types of clay soils affecting natural densification and consistency provides a reasonable approach to use of soil densification in the construction classification of soils.