Towards sustainable cement: Review of blended binder systems and performance-based specification strategies

Cement production contributes nearly 8% of global greenhouse gas emissions. Although supplementary cementitious materials (SCMs) offer significant decarbonization potential, their broader adoption is limited by prescriptive standards that constrain binder formulation. This review advocates a performance-based classification framework grounded in measurable outcomes such as strength and durability to support innovation in blended binders. A critical review of global standards highlights compositional limitations and positions ASTM C1157 as a scalable model validated through real-world applications. The study introduces the Environmental Disturbance Index (EDI), a composite metric combining strength, durability, and CO 2 emission to integrate sustainability into binder performance. A techno-economic analysis complements the EDI results, identifying systems with both environmental and cost advantages. The study proposes the STRONG approach to address early-age performance challenges common to high-SCM binders, focusing on synergistic blending, thermal activation, particle refinement, and nano-enhancement strategies. This work offers a roadmap for transitioning to performance-driven sustainable cement-based materials.