The Effectiveness and Efficiency of Implementing Fast Set Concrete in Reparation and Reinstatement of Concrete Pavements

AUTHORS: Tean, T. S.; and Wong, Z.D.

ABSTRACT: The project management triangle comprises three crucial components: time, cost, and quality, all of which must be carefully balanced by stakeholders in construction projects. In operational domains such as airports, ports, bus depots, and cargo areas, time assumes paramount importance due to the imperative of minimizing construction downtime. This research endeavors to evaluate the advantages of employing fast-set concrete in repair and reinstatement endeavors, focusing on time, cost, and quality considerations. The study utilizes rapid-setting patch cement to produce fast-set concrete, a technology traditionally limited to thicknesses of up to 75mm. Through the dedicated efforts of our research engineers and collaboration with suppliers, a breakthrough was achieved by optimizing the design mix, allowing fast-set concrete to maintain optimal performance at thicknesses of up to 400mm. This modified design mix was successfully employed in fast-set concrete projects at Singapore Changi Airport, resulting in the project's completion with minimal disruption to airport operations. In terms of quality and time, fast-set concrete demonstrates the capability to attain an initial compressive strength exceeding 40MPa within 3 hours, with strength gradually increasing over time. Reconstruction activities were strategically scheduled during off-peak hours or midnight closures, ensuring uninterrupted Changi Airport operations. Despite the relatively higher material costs associated with fast-set concrete compared to conventional concretes, the overall construction expenditure is lower due to the elimination of downtime and disruptions in operational areas.