Effect of Microstructure on the Mechanical Properties of Steel Fiber-Reinforced Recycled Concretes.
MATERIALS 2022;
15:ma15114018. [PMID:
35683316 PMCID:
PMC9182112 DOI:
10.3390/ma15114018]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 05/26/2022] [Accepted: 05/29/2022] [Indexed: 12/10/2022]
Abstract
A steel fiber-reinforced recycled concrete (SFRRC) is a porous material, and its macromechanical properties are affected by its microstructure. To elucidate the change rules and internal mechanisms of the mechanical properties of SFRRCs, the mechanical properties and failure modes of SFRRCs were studied at different water–cement ratio, replacement rate of recycled concrete aggregate (RCA), and steel fiber content. Moreover, the microstructures of the interface transition zones (ITZ) of the SFRRC specimens were tested by scanning electron microscopy and mercury intrusion, and the effect of the microscopic pore structure on the macromechanical properties of SFRRC was analyzed. The research results showed that an appropriate amount of steel fibers could reduce the size and number of cracks in the ITZ and improve the pore structure of an SFRRC. Based on the fractal dimension, porosity and other factors, the quantitative relationship between the macromechanical properties and microscopic pore structure parameters of SFRRCs was established.
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