CSA Concrete Road Slab Replacements A Review of International Practice and Literature

Calcium sulfoaluminate (CSA) cements present an opportunity to improve upon a number of the shortcomings of ordinary Portland cement (OPC). The fast setting and rapid strength gain characteristics of CSA cements have led to a worldwide uptake in the operational maintenance area. The use in road and airfield pavements is predominately in overnight concrete slab replacements, where time is of the essence and trafficking of slabs is required within a few hours of placement. What is often overlooked, however, is the performance of CSA-based concretes in terms of short term volumetric stability and long term durability properties in road pavements. Further, the potential that exists in reducing CO2 emissions when using CSA cements in place of OPCs in concrete pavement is also overshadowed by operational requirements. With increasing attention on global warming and the role that OPC manufacture plays in contributing to CO2 emissions, pressure on the worldwide cement industry to commit to real reduction targets is ever growing. CSA cements may indeed play a pivotal role in working towards a more sustainable industry for future cement and concrete supply in Australia. A critical review of international practice and literature is synthesised, allowing practitioners in the field to come up to speed with current state of the art, practice and use of CSA-based concrete technologies in road pavements. In particular, the drying shrinkage, abrasion resistance and carbonation behaviours of CSA-based concretes in-situ in the short and long-term will be reviewed. Recommendations will be made for future research into CSA concrete for road pavements based on gaps in the literature