Evaluate the use of reclaimed concrete aggregate in french drain applications.

PDFTech ReportBDK 78 TWO 977-12Concrete aggregatesRecycled materialsDrainage structuresFines (Materials)PermeabilityEvaluationCompressive strengthHeat of hydrationPhysical propertiesFloridaFlorida. Dept. of Transportation. Office of ConstructionNam, Boo HyunBehring, ZacharyKim, JinyoungChopra, ManojUniversity of Central Florida. Dept. of Civil, Environmental and Construction EngineeringUnited States. Dept. of TransportationUS Transportation CollectionRecycled concrete aggregate (RCA) is often used as a replacement of virgin aggregate in roadfoundations (base course), embankments, hot-mix asphalt, and Portland cement concrete; however, theuse of RCA in exfiltration drainage systems, such as French drains, is uncommon. The primaryconcerns with using RCA as a drainage media are the fines content and the precipitation of calciumcarbonate to cause a reducing in filter fabric (geotextile) permittivity. RCA was tested for its physicaland chemical properties, and aggregate cleaning/washing methods were applied to evaluate the finesremoval processes. The potential for RCA rehydration was evaluated by the use of compressivestrength, pH, heat of hydration, and time of setting tests. Permeability testing on RCA was conductedunder varied testing conditions, such as, percent fines addition, hydraulic gradient, and tubing andpermeameter sizes. In addition, a long-term permeability was monitored to measure the cloggingbuildup due to RCA fines and calcite precipitation