Engineering has long relied on concrete as its backbone, but the extraction of natural aggregates—sand and gravel—is coming under growing scrutiny for its environmental toll. A new review by Panaligan Tristan Roy, a chemical engineer at Mapúa Malolan Colleges Laguna, suggests that recycled concrete aggregate (RCA) could offer a scalable alternative, one that aligns with circular economy principles and climate-responsive infrastructure.
The study, published in *E3S Web of Conferences* (translated from *E3S Web des Conférences*), highlights a critical challenge: RCA’s performance is often undermined by adhered mortar and weak interfacial transition zones, which raise water absorption and lower mechanical strength. “These aren’t just technical issues,” Roy notes. “They translate directly into cost and reliability concerns for contractors and energy infrastructure planners.”
Yet the review also points to promising solutions. Chemical treatments, bio-based surface modification, and carbonation curing are among the methods showing real potential to enhance RCA performance while enabling carbon storage within cementitious systems. “We’re not just recycling waste,” Roy says. “We’re turning it into a carbon-sequestering building material.”
The commercial implications for the energy sector are significant. As utilities and oil & gas operators expand facilities in tropical regions like the Philippines, the demand for durable, low-carbon construction materials is rising. RCA could reduce reliance on virgin aggregates, cut transport emissions, and align with procurement policies favoring sustainable sourcing.
Still, challenges remain. Field-scale validation under tropical conditions and AI-driven mix optimization are key priorities. Roy emphasizes that success will depend on context-sensitive life cycle assessment and alignment with local standards and logistics.
For industries under pressure to decarbonize, RCA represents more than an environmental gesture—it’s a practical pathway toward resource efficiency. And as Roy’s research suggests, the future of sustainable construction may lie not in extracting new materials, but in reimagining what we already have.