Carbon emissions associated with two types of foundations: CP-II Portland cement-based composite vs. geopolymer concrete

ABSTRACT The cement industry is the second-largest single industrial emitter in the world and therefore has an important role to play in reducing the intensity of its carbon emissions: participation of the sector is important to contribute to the goal of the Paris Climate Change Agreement to limit global warming. One of the strategies for reducing the carbon footprint of the cement industry is substitution of Portland cement, which is a component of the concrete mix widely used as a construction material worldwide. Geopolymer cement has emerged as an alternative for Portland cement, with several advantages. This study applied the Life Cycle Assessment methodology to quantify the carbon emissions associated with 1m3 of two types of concrete (concrete PC-II cement-based Portland cement vs. geopolymer concrete). Geopolymer concrete presented almost 43% less carbon emissions, while also presenting high physic-chemical performance. It was verified that geopolymer concrete has the potential to help mitigate climate change, and can be employed as part of the plan to minimize the emissions associated with the construction sector.摘要 水泥行业是全球第二大单一工业排放源，因此在降低自身碳排放强度方面肩负重要责任。该行业的参与对实现《巴黎气候变化协定》限制全球变暖的目标具有关键意义。降低水泥行业碳足迹的策略之一，是对硅酸盐水泥（Portland cement）进行替代——该材料是全球范围内广泛用作建筑材料的混凝土混合料的核心组分。地质聚合物水泥（geopolymer cement）已成为硅酸盐水泥的替代方案，具备多项显著优势。本研究采用生命周期评估（Life Cycle Assessment）方法，量化了两种混凝土（以硅酸盐水泥为基材的PC-II型水泥混凝土与地质聚合物混凝土）每立方米的相关碳排放量。结果表明，地质聚合物混凝土的碳排放量较前者低近43%，同时拥有优异的理化综合性能。研究证实，地质聚合物混凝土具备助力减缓气候变化的潜力，可作为降低建筑行业相关碳排放方案的组成部分予以应用。