RECYCLING OF PORTLAND CEMENT CONCRETE PAVEMENT, JOHNSON COUNTY, KANSAS

In recent years there has been increasing interest in recycling construction materials. Surface courses of bituminous pavements are currently being actively recycled all over Kansas. The recycling of portland cement concrete pavements (PCCP) can help alleviate any material disposal problems during construction, especially in urban areas and reduce the consumption or importation of virgin aggregate into aggregate poor areas. Two test sections using the coarser fraction from the original crushed PCCP were placed on K-7 in 1985. One section incorporated a recycled base and standard PCCP construction; another section was designed as a recycled base and recycled PCCP. Two other sections were control sections constructed with regular aggregate. Recycling of PCCP was not as economical on this project as using virgin aggregate. With all of the unknowns, inexperience and close proximity of virgin aggregate, it was not as cost effective as it could be in the western part of the state. The Recycled Base/Recycled Concrete section performed the best overall, but not by a great margin. It performed only slightly better than the control section. No projects are currently planned incorporating recycled PCCP, due to the extensive use of recycled portland cement treated base.