Characterization of waste recycled glass as a highway material
The success of glass recycling programs has resulted in an oversupply of waste recycled glass or glass cullet. The properties and strength of glass cullet aggregate mixes are influenced by maximum size of cullet, cullet content in the mix, type of conventional aggregate, and also the debris level in the cullet. A survey of State DOTs was done to determine their experiences with the use of glass cullet. Also, a survey among suppliers of cullet in Texas was done to determine the costs associated with procuring glass cullet. Based on these surveys, glass cullet was identified for use in base course, subbase, subgrade and embankments and also for backfill applications. A test program was devised to test the engineering suitability of glass cullet samples for the above mentioned applications. Stripping tests were also done to determine the adhesion of glass cullet and asphalt in the presence of water. Based on the results of these tests, it was found that glass cullet has properties similar to natural aggregates and could be used as a highway material. Specifications for use of glass cullet by the Texas Department of Transportation were also developed.