Multi-scale study on mechanical property and strength prediction of aeolian sand concrete. (30th June 2020)

• Record Type: Journal Article
• Authors: Li, Yugen; Zhang, Huimei; Liu, Guangxiu; Hu, Dawei; Ma, Xiangrong
• Is Part Of: Construction & building materials. Volume 247(2020)
• Publication Date: 2020-06-30
• Subjects: Aeolian sand concrete -- Mechanical properties -- Influence mechanism -- Multi-scale -- Strength prediction; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.118538
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: It is the best for strength and workability with 20% replacement of aeolian sand. Influence mechanism of aeolian sand on strength of concrete is revealed. Effect of aeolian sand on strength is due to its chemical and physical properties. Strength prediction model for ASC agrees well with the test results. Abstract: The aim of this work is to promote the utilization of aeolian sand for concrete production. The workability and mechanical property of aeolian sand concrete (ASC) is studied. The effect mechanisms of aeolian sand on the mechanical property of concrete are revealed from multiple scales. For the macro scale, use the pressure tester to test the compressive strength. For the mesoscopic, use the scanning electron microscope (SEM) to observe the structure of the interface transition zone (ITZ) and the nuclear magnetic resonance (NMR) to test the pore structure. Meanwhile, the distribution of chemical bonds is analyzed by the Fourier transform infrared (FT-IR) spectrometer and the microstructure of hydration products are characterized by the SEM for the microscopic. The results show that using parts of aeolian sand can improve the working and mechanical property of concrete. The physical influence mechanism is that it perfects the gradation of the aggregate and increases the density of concrete, reduces the effect of aggregate size and micro-region bleeding, improves the structure of ITZ and pores. For the chemical, it may accelerate the hydration reaction speed of cement and change the microstructure of hydration products. Finally, a strength prediction model of ASC is established based on the published and tested data, which agrees well with the tested result.