Challenge of adopting relatively low strength and self-cured geopolymer for road construction application: a review and primary laboratory study

ABSTRACT

In road construction industry, more sustainable construction materials are required. Currently, for modern road pavement rehabilitation and construction, cement is often used as a stabilising agent. With the rapid growth of road traffic and freight, cement usage substantially increases in amount of CO₂ emissions. Hence, how a geopolymer, defined as a future sustainable construction material, can be alternatively used in the road pavement. This paper aimed to reveal the possibility of using geopolymers in road construction. A literature review process and a primary laboratory study were performed. The newly developed concept of a relatively low strength (LS-GP) and self-cured geopolymer may be practical when used as a road stabilising agent. The lower strength requirements of a road construction material in comparison to those of normal concrete application could ease any difficulties with geopolymer production. The available technology for geopolymers cured at an ambient temperature condition could enhance such a possibility. Results from the primary laboratory study confirmed such a concept. An applicable level of alkaline solution concentration led to an increase in strength. While, a high calcium content in standard road base material can rapidly react with alkaline activators, such that a self-cured geopolymer could be used.

KEYWORDS:

• Ambient curing process
• crushed-rock based geopolymer
• geopolymer
• relatively low strength cement
• road pavement construction materials
• self-cured geopolymer

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by TRF Mid-Career Research Grant [Grant Number RSA5980070] and TRF Distinguished Research Professor Grant [Grant Number DPG6180002].