DENVER AREA AGGREGATE BASE COURSES

摘要

The aggregate base courses available in the Denver area are typically susceptible to slight variations in moisture content of the material. Pavement failures in the first 10 years of service revealed most of the bases available in the Denver area contain a moisture susceptible silt material as the binder rather than the more moisture stable clay particles. Research revealed that a 2 percent increase in moisture content generally reduces Resilient Modulus values by 25 percent. Solutions to the aggregate failures have included cement treatment of the aggregate base, stabilization of the subgrade, and use of interwoven fabrics between the aggregate base and the clay subgrades. The additional cost of treatments initially discouraged the use of aggregate bases in pavement sections. With the trends of increasing full depth asphalt concrete sections and required subgrade stabilization, the use of treated aggregate bases has become more cost effective in recent years.