For additional information,
visit the Portland Cement Association - Soil Cement

PCA, Southeast Region Consultant Doug Smith, P.G. 394 Elmburg Road Shelbyville, KY 40065 Phone: 502-321-0148 Fax: 502-829-9640 dsmith@cement.org     Andrew Maybee, P.E. CPAT Executive Director 230 Grove Road Collierville, TN 38017 Phone: 901-488-3296 Fax: 770-497-0099 amaybee@pavementse.com     Matt Jeffers Pavement Applications Director Tennessee 8183 Coley Davis Road Nashville, TN 37221 Phone: 615-504-1312 Fax: 770-497-0099 mjeffers@cement.org     North Carolina South Carolina Jerry Reece Cell: 336-508-5921 jreece@pavementse.com Bill DuBose Cell: 803-206-1030 bdubose@pavementse.com     Soil Cement Resources Available: EB236 - Guide to Cement Treated Base (CTB) Cement-treated base (CTB) is a general term that applies to an mixture of native soils and/or manufactured aggregates with measured amounts of portland cement and water that is compacted and cured to form a strong, durable, frost resistant paving material. Other descriptions such as soil-cement base, cement-treated aggregate base, cement-stabilized base are sometimes used. EB003 - Soil Cement Construction Handbook Describes construction operations using mixed-in-place and central-plant-mixed techniques. Includes construction of roads, shoulders, parking and storage areas; recycling of flexible pavements and cement-modified soils.       IS008 - Suggested Specifications for Soil-Cement Base Course Construction

What is Soil-Cement? Soil-cement is an engineered material designed and constructed for various pavement applications or material characteristics. The best soil-cement product is the one best suited to the specific application. Each of these cement-based pavement materials are engineered specifically for their intended purpose as follows: Cement-Modified Soil (CMS) – Many problems can occur during construction when silt and clay soils are encountered, particularly when they are wet. These soils can be soft, plastic, and difficult to compact. CMS is used to improve the engineering properties and construction characteristics of silt and clay soils by reducing the plasticity and enhancing the compaction and strength of the material. With 3 – 5% (by dry weight) of cement used to modify the soil, the final product is an improved construction material. Cement-Treated Base (CTB) – CTB a general term that applies to all hardened soil-cement that meets the project specified minimum durability and strength requirements. The soil-cement can be mixed-in-place (like CMS) using on-site soils or mixed in a central plant using selected aggregate. However, CTB uses more cement than CMS resulting in a strong, durable, frost resistant layer for the pavement structure. Typical cement contents range from 3 – 10% cement, resulting in 7-day unconfined compressive strengths from 300 – 800 psi (2.1 - 5.5 MPa). Full-Depth Reclamation (FDR) – A special case of cement-stabilization is FDR, where aggregate for the cement-stabilized base is obtained by pulverizing and recycling the old asphalt surface and base material. This construction procedure is very similar to mixed-in-place construction, except that there is an aggregate specification for the blend of the pulverized asphalt and old base material. FDR commonly uses 4 – 6% cement and results in 300 – 400 psi (2.1 – 2.8 MPa) unconfined compressive strengths in 7 days. Additional Resources: www.recyclingroads.org Portland Cement Association