Technical Paper on Foam Asphalt TechnologyCold Foam Asphaltic Concrete
Cold foam in-place recycled asphaltic concrete (CFA) is now a well established methodology for in-place recycling of distressed pavements with a successful track record of completed projects throughout California. This track record includes many general engineering and specialty subcontractors with experience in conventional uses of CFA. Initially, projects in California were most commonly applied to rural applications, with Caltrans using CFA successfully on numerous rural highways in northern and southern California. While the application of CFA in California is still not common, successful projects can now be shown by example to interested parties, both private and public agencies, where CFA has successfully been implemented. For those readers that are not familiar with the basic procedure, it consists of grinding and pulverizing the existing pavement section and addition of "foam" bituminous materials, followed by compaction using conventional compaction equipment (sheepfoot compactor, steel drum roller, pneumatic rollers) to construct a new stabilized pavement subgrade over which an asphaltic concrete (AC) overlay is typically applied. Typical treatment depths vary from 6 to 12 inches, with typically 2 to 4 inches of AC overlay to complete the project.
Condor has experience on the largest CFA projects in northern California. These include several major projects in the City of Chico, California as well as projects within Yolo County and San Joaquin County. Condor has performed these services on rural roads without vertical control on the shoulders, as well as city multi-lane and divided streets with vertical control at the medians and curbs. In addition to CFA full depth reconstruction of roadways, Condor has provided alternative full depth reconstruction using lime and cement stabilization when the pavement and subgrade conditions indicate that CFA is not a feasible solution. Condor is one of two firms within Northern California that owns and operates a CFA mix design testing apparatus.
— Oakdale Irrigation District