Strategized Reduction of Greenhouse Gas Emissions Through Predicting and Extending the Service Life of Concrete Pavements and Bridges

Cracking, permeability, and diffusion are common problems in concrete elements that substantially impact the service life of transportation infrastructure, such as concrete pavements and bridge decks. These properties generally determine the vulnerability of concrete due to chemical attacks, corrosion, freeze-and-thaw cycles, shrinkage, creep, and thermal effects. They may influence later cracking when exposed to adverse environmental conditions. Enhancement of the interfacial transition zone (ITZ) through proper curing and pozzolanic bonding plays a vital role in controlling shrinkage and, thus, reducing early-age cracking and other deficiencies. However, the accelerated nature of transportation projects and constrained lane-closure regulations often require reduced construction time facilitated by fast-setting cementitious materials, which is not practical for applying conventional external curing methods and demands significant cementitious contents. The application of lightweight aggregates is an innovative method to address this problem. The high absorption rate of fine, lightweight aggregates introduces a high potential to preserve water for cement hydration during curing. The pozzolanic properties of porous lightweight aggregate strengthen the ITZ. Further, concrete materials with lightweight aggregates exhibit lower thermal expansion and lower modulus of elasticity, both influential in controlling thermal cracking. Furthermore, the embodied energy and greenhouse gas emissions associated with such applications reduce the environmental footprint of projects.