Durability Assessment of Recycled Concrete Aggregates for Use in New Concrete. Phase 1 - Report.

摘要

This research project, started in the 2009-2010 funding cycle, had the primary goal of investigating the long-term durability of concrete incorporating recycled concrete aggregate (RCA) through accelerated laboratory testing. Of particular interest was the possibility of pronounced alkali-silica reaction (ASR), an expansive reaction that results in cracking and a reduction in the service life of concrete structures, in new concrete incorporating RCA which may have active ASR. This area of concern was identified by several states as a major research need in a recent Federal Highway Administration study. Currently the use of recycled concrete as aggregate in the United States is predominately limited to use in pavement base or subbase material and nonstructural fill, with the remainder being landfilled. As the availability of natural aggregate sources is reduced and government initiatives, as well as public demand, push the use of sustainable construction practices, the need for alternative aggregate sources will continue. One of the most logical and environmentally friendly practices is recycling concrete taken out of service into a source of aggregate for new construction.