Date of Award
Civil and Environmental Engineering
Concrete -- Recycling, Sustainable construction, Building materials -- Recycling, Aggregates (Building materials), concrete recycling sustainability construction recycling
The demolition of concrete structures has made concrete debris the largest portion of the waste stream in the U.S. With landfills becoming scarcer, the need to recycle demolition debris is becoming increasingly relevant. An effective way to recycle this material is to produce recycled concrete aggregate (RCA) and use this material in the reconstruction of buildings and roads. Producing and re-using RCA will reduce landfill waste and save energy by minimizing the production and transport of natural aggregates. The focus of this thesis is to quantify how much energy can be saved by producing and re-using RCA instead of landfilling demolition debris and using natural aggregates. However, in order to do this, a thorough understanding of RCA and the natural aggregates industry must first be addressed. Through literature review, the properties, uses, production, and criteria to use RCA was determined. The availability and energy required to produce and transport natural aggregates was also determined. Three case studies were conducted in order to perform analysis on energy savings associated with RCA. In each case, a building was demolished and RCA was produced and re-used from the demolition debris. All of the energy inputs from the production and transportation of the RCA to its re-use site was calculated. This data was compared to the energy inputs to landfill demolition debris and produce and transport virgin aggregates to those same sites. For each case, energy savings were seen by producing and re-using RCA. However, these savings varied greatly for each case. It was determined that variables such as re-use location, location of the quarry/distribution center and modes of transportation used in shipping were the main contributors for these differences. For this reason, it was determined that this model is effective, but that the difference in the variables can have huge impacts and are all project specific. Therefore, this analysis must be made on a case by case basis to determine if this is a sustaina
Dardis, Joseph M., "Recycling Concrete for Sustainable Construction" (2012). ETD Archive. 371.