Strength Assessment of Soil Cement

Abstract

Soil cement is a mixture of soil, portland cement, and water that is compacted and cured to form a pavement base. Due to construction practices and variances in core strengths, questions have arisen concerning quality control and testing protocol. A major concern in this area is strength assessment, which became the main objective of this research.

In order to develop a method that reliably assesses the strength of soil cement base, a laboratory testing program was developed to evaluate the suitability of using the dynamic cone penetrometer based on ASTM D 6951 and molded cylindrical samples based on ASTM D 1632. Testing was done to establish the relationship between the dynamic cone penetrometer and molded compressive strength between 100 and 800 psi.

Based on the results from this research it can be concluded that the molded cylinder specimens should be cured using the sealed plastic bag method, the dynamic cone penetrometer is able to penetrate specimens with strengths less than approximately 800 psi, and a logarithmic function is the best fit for the correlation between the dynamic cone penetrometer and the molded cylinder strength. It is recommended that soil cement cylinders and the dynamic cone penetrometer be considered for quality assurance for the strength assessment of soil cement base.