Life Cycle Assessment and Impact Correlation Analysis of Fly Ash Geopolymer Concrete

• Published in: Materials 2021-12, Vol.14 (23), p.7375
• Main Authors: Shi, Xiaoshuang, Zhang, Cong, Liang, Yongchen, Luo, Jinqian, Wang, Xiaoqi, Feng, Ying, Li, Yanlin, Wang, Qingyuan, Abomohra, Abd El-Fatah
• Format: Article
• Language: English
• Subjects: Carbon; Carbon dioxide; Caustic soda; Cement; Climate change; Compressive strength; Concrete mixing; Construction industry; Correlation analysis; Curing; Design; Emission analysis; Emissions; Energy consumption; Environmental impact; Fly ash; Geopolymers; Greenhouse gases; Impact analysis; Impact factors; Inventory; Life cycle assessment; Multivariate analysis; Parameter sensitivity; Portland cements; Sodium; Sodium hydroxide; Sodium silicates; Variance analysis
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma14237375

Geopolymer concrete (GPC) has drawn widespread attention as a universally accepted ideal green material to improve environmental conditions in recent years. The present study systematically quantifies and compares the environmental impact of fly ash GPC and ordinary Portland cement (OPC) concrete under different strength grades by conducting life cycle assessment (LCA). The alkali activator solution to fly ash ratio (S/F), sodium hydroxide concentration (CNaOH), and sodium silicate to sodium hydroxide ratio (SS/SH) were further used as three key parameters to consider their sensitivity to strength and CO2 emissions. The correlation and influence rules were analyzed by Multivariate Analysis of Variance (MANOVA) and Gray Relational Analysis (GRA). The results indicated that the CO2 emission of GPC can be reduced by 62.73%, and the correlation between CO2 emission and compressive strength is not significant for GPC. The degree of influence of the three factors on the compressive strength is CNaOH (66.5%) > SS/SH (20.7%) > S/F (9%) and on CO2 emissions is S/F (87.2%) > SS/SH (10.3%) > CNaOH (2.4%). Fly ash GPC effectively controls the environmental deterioration without compromising its compressive strength; in fact, it even in favor.