COMPRESSIBILITY OF FIELD COMPACTED CLAY

PING-SIEN LIN, Purdue University

Abstract

This study investigates the compressibility of a plastic Indiana clay (St. Croix) compacted in the field. Correlation among compaction variables and compacted properties was a prime objective. The clay was compacted to three levels of effort and at five levels of water content by two kinds of rollers. As-compacted compressibilities were assessed in the laboratory oedometer, and compaction prestress values were interpreted from the e- log p curves. These values were always less than the nominal roller pressures previously applied to the soil. A regression model for prestress was written in terms of the compaction pressure and an interaction between pressure and compaction water content. Other compacted samples were saturated under three levels of confinement, with the aid of vacuum and back pressure. The subsequent volume changes depended upon the compaction variables, as well as the confinement during saturation. It was possible to develop a correlation among the volumetric strain, the initial void ratio, the compaction water content and the confinement during saturation. Soaked compressibilities were also measured. A similar study on the compressibility characteristics of laboratory compacted samples of the same area soil had been conducted, and the coupling of the relations for field compaction with those previously established for laboratory compaction is reported here.

Degree

Ph.D.

Subject Area

Civil engineering|Cartography

COinS