Geopolymer as underwater concreting material: A review

Underwater concrete is one of the special types of high-performance concrete in the current industry which is commonly used to construct bridges, dams and structures whose foundation is built underwater. In contrast with typical concrete, the implementation of concrete underwater requires different techniques due to the different concrete properties in order to ensure successful implementation. A new material called geopolymer is now widely promoted for its ability to replace ordinary Portland cement (OPC) as a binder due to its green technology. Numerous researches have established that the geopolymer has comparable strength and chemical resistivity compared to OPC. However, to date, only limited researches had been conducted to examine the use of geopolymer as an underwater concreting material. From the review that has been done, it can be concluded that the requirements for underwater concreting material should include washout resistivity, workability and durability in addition to high strength. This review highlights that the geopolymers are proven to provide excellent strength, durability and workability in accordance with the EFNARC standard. Finally, future research opportunities are also presented in this review with regards to the potential of geopolymer in replacing OPC as underwater concreting material.