Field performances of chemically stabilized quarry by-products evaluated through accelerated pavement testing

Quarry Byproducts (QB) are generated from quarry operations of blasting, crushing, and screening rocks to produce aggregate materials. QB are mostly less than 6 mm in size, and pose a major environmental and economic challenge for quarries when they accumulate in large quantities. Recent research at the Illinois Center for Transportation evaluated several new sustainable applications to utilize QB, or QB mixed with other recycled materials, in chemically stabilized layers in pavement construction. Seven full scale test sections were constructed to evaluate the use of quarry by-products in base and subbase (i.e. inverted pavements) applications for low and medium volume flexible pavement roads. Test sections were stabilized with 3% cement or 10% Class ‘C’ fly ash, by dry weight. Test sections were constructed over a subgrade with an engineered strength of unsoaked California Bearing Ratio (CBR) of 6%. The constructed test sections were evaluated using accelerated pavement testing and frequent measurement of rutting. This paper presents results for field rutting performance trends of these seven test sections, evaluated in the laboratory and in the field through accelerated pavement testing. Preliminary results indicate satisfactory rutting performance of all the evaluated application, and no surface cracking were observed, which indicates that QB and QB mixed with other recycled materials, such as recycled asphalt pavements and recycled concrete aggregates, can be successfully used as subsurface layers for pavement applications.