Fracture Behavior of Steel Slag Powder-Cement-Based Concrete with Different Steel-Slag-Powder Replacement Ratios

• Published in: Materials Vol. 15; no. 6; p. 2243
• Main Authors: Zhuo, Ke-Xian, Liu, Guo-Tao, Lan, Xue-Wei, Zheng, Dong-Ping, Wu, Si-Quan, Wu, Pei-Zong, Guo, Yong-Chang, Lin, Jia-Xiang
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 18.03.2022; MDPI
• Subjects: Aggregates; Aluminum; Calcium oxide; Cement; concrete; Concrete mixing; Crack opening displacement; Fracture mechanics; fracture performance; Fracture testing; Fracture toughness; Lime; Mechanical properties; Metal powders; Particle size; replacement ratio; Slag; Steel; steel-slag powder; Tensile strength; China; concrete; replacement ratio; steel-slag powder; fracture performance
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma15062243

The influence of different replacement ratios of steel-slag powder as cement-replacement material on the fracture performance of concrete is studied in this paper. A three-point bending fracture test is carried out on slag powder-cement-based concrete (SPC)-notched beams with steel-slag powder as cementitious materials, partially replacing cement (0%, 5%, 10%, 15%, and 20%). Load-deflection curves and load-crack-opening displacement curves of SPC-notched beams with five different replacement ratios of steel-slag powder were obtained. The effects of different steel-slag-powder replacement ratios on the fracture properties (fracture energy, fracture toughness, and double-K fracture parameters) of the SPC were analyzed and discussed. The results showed that the incorporation of appropriate steel-slag powder can affect the fracture performance of SPC. Compared with concrete without steel-slag powder, adding appropriate steel-slag powder can effectively improve the bond performance between aggregate and matrix because the steel-slag powder contains hydration activity substances such as calcium oxide and aluminium trioxide. The fracture energy and fracture toughness of SPC increased and then decreased with the increase in steel-slag-powder replacement ratios, and the SPC concrete showed best fracture performance with a 5% steel slag powder replacement ratio. Its fracture energy increases by 13.63% and fracture toughness increases by 53.22% compared with NC.