Restrained shrinkage cracking of self-consolidating concrete roads

Abstract

The present study is dedicated to investigate the liability of continuously reinforced concrete pavement (CRCP) cast with self-consolidating concrete (SCC) to restrained shrinkage cracking and the values of restraint stresses in these pavements. SCC, which is becoming increasingly popular due to its several superiorities over conventionally vibrated concrete (CVC), has higher amounts and rates of shrinkage compared to CVC. The higher risk of restrained shrinkage cracking of SCC is a great cause of concern in pavement construction as the penetration of water, chemicals, and salts increases the risk of corrosion of reinforcement. In the present study, an analytical restraint stress expression was developed for typical CRC pavements by modifying the restraint stress equation developed previously for RC beams. Using this equation, the restraint stresses induced to the longitudinal reinforcement by the rigid pavement, cast with CVC or SCC, were calculated for eight different example sections. These restraint stress values were found to reach up to 50% of the limit stresses of bars, allowed by the design guidelines, when the pavement is cast with SCC. The amounts of longitudinal reinforcement used in typical CRCP roads were found to be more critical when the pavement is cast with SCC.

Keywords

• concrete roads
• restraint stress
• self-consolidating concrete
• shrinkage cracking