Piloted Quality Control Techniques Using the Plastic Mold Compaction Device for Cement Stabilized Materials

Abstract

Some highway agencies make heavy use of cement-stabilized materials (i.e., soil-cement) for subbase and base pavement layers. Recently, several soil-cement studies have been funded by highway agencies. Through one of these studies, the plastic mold compaction device (PM Device) was developed, which is designed to compact 2:1 height/diameter specimens inside plastic molds. The most novel aspect of the PM Device is the potential to interface mechanistic-empirical pavement design, laboratory mixture design, and construction quality control/quality assurance (QC/QA) activities. To date, the PM Device has been evaluated with respect to design activities, but little work has been performed to evaluate the PM Device’s effectiveness as a tool during construction. This paper focuses on three pilot projects in which the PM Device was evaluated as a potential QC/QA tool. The PM Device demonstrated merit as a QC/QA tool for A-2-4 classified materials, but the current PM Device does have particle size limitations. The PM Device produced consistent specimen densities with a predetermined compactive effort, provided an indication of cement content of field-mixed material via unconfined compressive strength testing, and correlated favorably with field cores in a limited assessment. The investigations presented need to be supplemented by additional projects to develop a framework for the PM Device to be implemented into an agency QC/QA program.