Abstract
This article explores key factors shaping the transition of the precast concrete sector toward net-zero carbon. While not exhaustive, it highlights areas of scientific and technical interest for a specialist audience. The discussion is structured around priority themes: beginning with cement and clinker replacement, followed by production efficiency improvements, rethinking steel usage, carbon sequestration strategies, and, finally, structural optimisation or volume reduction. These areas are often interdependent: for instance, clinker replacement, production efficiency, and structural optimisation are all influenced by the 16 – 18 hour production cycle typical of precast manufacturing. Unlike the readymix sector, precast operates on a fast-paced, low-cost, high-volume model where rapid turnaround is essential to controlling overheads. The sector predominantly uses CEM II/A-L (or LL), incorporating limestone powder, although some manufacturers still rely on CEM I. For structural elements, CEM III/A with up to 50% GGBS is also employed. However, due to the comparable cost of GGBS and CEM I, GGBS is often reserved (correctly) for applications requiring enhanced durability. A major barrier to reducing carbon emissions in precast is the need for early strength gain, which limits the adoption of lower-clinker cements such as calcined clay blends. Addressing this challenge is critical to enabling broader use of low-carbon binders. This article also highlights the contributions of the materials research team at Queen’s University Belfast in supporting the precast industry in Northern Ireland on its path to net-zero.
Keywords
clinker replacement, calcined clays, industrial by products, digitalisation, volume reduction.
DOI
10.5703/1288284318106
Recommended Citation
Nanukuttan, Sreejith; Doherty, Rory; McPolin, Daniel; Soutsos, Marios; and Russell, Mark, "Challenges and Opportunities in Concrete Precast Sector and its Transition to a Net-zero Future" (2025). International Conference on Durability of Concrete Structures. 5.
https://docs.lib.purdue.edu/icdcs/2025/keynote/5
Challenges and Opportunities in Concrete Precast Sector and its Transition to a Net-zero Future
This article explores key factors shaping the transition of the precast concrete sector toward net-zero carbon. While not exhaustive, it highlights areas of scientific and technical interest for a specialist audience. The discussion is structured around priority themes: beginning with cement and clinker replacement, followed by production efficiency improvements, rethinking steel usage, carbon sequestration strategies, and, finally, structural optimisation or volume reduction. These areas are often interdependent: for instance, clinker replacement, production efficiency, and structural optimisation are all influenced by the 16 – 18 hour production cycle typical of precast manufacturing. Unlike the readymix sector, precast operates on a fast-paced, low-cost, high-volume model where rapid turnaround is essential to controlling overheads. The sector predominantly uses CEM II/A-L (or LL), incorporating limestone powder, although some manufacturers still rely on CEM I. For structural elements, CEM III/A with up to 50% GGBS is also employed. However, due to the comparable cost of GGBS and CEM I, GGBS is often reserved (correctly) for applications requiring enhanced durability. A major barrier to reducing carbon emissions in precast is the need for early strength gain, which limits the adoption of lower-clinker cements such as calcined clay blends. Addressing this challenge is critical to enabling broader use of low-carbon binders. This article also highlights the contributions of the materials research team at Queen’s University Belfast in supporting the precast industry in Northern Ireland on its path to net-zero.
