A laboratory and field study was conducted related to chemically stabilized pavement layers, which is also referred to as soil-cement. Soil-cement practices within MDOT related to Class 9C soils used for base layers were evaluated in this report. The overall objective was to provide draft design and quality control guidance that could be incorporated and/or specified to improve performance of soil-cement base layers. A total of 2,101 tests were performed to evaluate a variety of parameters. Testing included strength versus time, strength variability, compaction, elastic modulus, wheel tracking, and thermal profile measurement. One key component of the research was development of economical thermal profile equipment to evaluate compacted soil-cement during the first few hours of hydration. The primary intention of this equipment is a quality control tool. Another key component of the research was development of equipment that allowed soil-cement to be compacted inside a plastic mold that could be used for laboratory mix design, specimen preparation for pavement layer thickness design, and for quality control. Results indicated the plastic mold compaction approach has many advantages and should be implemented into design and quality control operations. At the present time, widespread use of thermal profiles for quality control is not recommended. Additional study, however, could result in effective implementation of thermal profiles into soil-cement construction projects on a more frequent basis.

US Transportation Collection