In the face of rising sea levels and the increasing scarcity of traditional construction materials, researchers are turning to innovative solutions to bolster the resilience of coastal and island infrastructure. A recent study led by Liang Cao from the College of Architecture and Civil Engineering at Beijing University of Technology has shed new light on the potential of ferroaluminate cement (FAC) mixed with calcareous sand powder (CSP) to withstand the corrosive effects of seawater.
The study, published in *Case Studies in Construction Materials* (translated from Chinese as “Case Studies in Construction Materials”), explores how FAC-CSP performs in three distinct water environments: freshwater mixing and immersion (FF), freshwater mixing and seawater immersion (FS), and seawater mixing and immersion (SS). The findings reveal that CSP significantly alters the electrochemical properties of the cement in FS and SS environments, enhancing resistivity during the later stages of hydration. “CSP notably increases the resistivity of specimens at the later stages of hydration,” Cao explains, highlighting a key advantage for long-term durability.
While CSP does reduce the initial mechanical properties of the specimens, it contributes to strength enhancement over time. Moreover, seawater immersion compensates for the strength loss induced by CSP, offering a promising solution for marine construction. “Seawater immersion significantly improves the strength of the specimens,” Cao notes, underscoring the potential for this approach in coastal engineering.
The study also delves into the micro-scale interactions between CSP and FAC. In FS and SS environments, specimens exhibit higher ettringite content, a critical hydration product that enhances strength and durability. The presence of CSP promotes more complete hydration of FAC, while seawater immersion increases the bound water content in the specimens. “The adsorption of CSP particles and the ionic contribution of seawater stimulate the formation of additional hydration products around the CSP particles,” Cao elaborates, explaining how these interactions fill gaps and strengthen the cement matrix.
For the energy sector, these findings could have significant implications. Offshore wind farms, desalination plants, and other coastal infrastructure projects often face the dual challenges of material scarcity and seawater corrosion. The use of FAC-CSP could offer a more sustainable and resilient alternative to traditional materials, reducing maintenance costs and extending the lifespan of critical structures.
As the world grapples with the impacts of climate change, innovative solutions like FAC-CSP could play a pivotal role in shaping the future of construction. By understanding the synergistic mechanisms at play, researchers and engineers can develop more robust and durable materials tailored to the unique demands of marine environments. This study not only advances our scientific knowledge but also paves the way for practical applications that could transform the energy sector and beyond.