Parameter inversion and microscopic damage research on discrete element model of cement-stabilized steel slag based on 3D scanning technology

Shuyong Wang; Guoxin Chen; Lingkai Zhang

doi:10.1016/j.jhazmat.2021.127402

Parameter inversion and microscopic damage research on discrete element model of cement-stabilized steel slag based on 3D scanning technology

J Hazard Mater. 2022 Feb 15;424(Pt A):127402. doi: 10.1016/j.jhazmat.2021.127402. Epub 2021 Oct 1.

Authors

Shuyong Wang¹, Guoxin Chen², Lingkai Zhang¹

Affiliations

¹ Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention, Xinjiang Agricultural University, Urumqi 830052, Xinjiang, China; College of Hydraulic and Civil Engineering, Xinjiang Agricultural University, Urumqi 830052, Xinjiang, China.
² Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention, Xinjiang Agricultural University, Urumqi 830052, Xinjiang, China; College of Hydraulic and Civil Engineering, Xinjiang Agricultural University, Urumqi 830052, Xinjiang, China. Electronic address: xjbnchgx@163.com.

PMID: 34879585
DOI: 10.1016/j.jhazmat.2021.127402

Abstract

The macro- and micro-physical properties of cement-stabilized steel slag (CSS) base materials in a highway project were studied. A discrete element model of CSS with a real steel slag shape was constructed using Particle Flow Code 3D and 3D scanning technology. The sensitivity between the macro- and micro-parameters of the sample was explored, and a nonlinear regression equation was established to analyze the relationship between these parameters. Uniaxial compression simulation tests were conducted on CSS with steel slag contents of 0%, 10%, 30%, and 50%. By combining contact calculation, crack location, energy tracking, acoustic emission (AE) monitoring, and other program systems, the macro- and micro-mechanical properties and micro-crack evolution law of the samples in the failure process were analyzed in terms of strength, energy, and fracture damage. The damage mechanism of CSS was also revealed. Results showed that with the increase in steel slag content, the elastic modulus and peak stress of the samples increased, the Poisson's ratio decreased, and the post-peak stress curve steepened, indicating obvious brittle failure characteristics. With the increase in steel slag content, the crack initiation stress, thickness of the fracture surface, and number of internal micro-cracks in CSS increased exponentially. In the uniaxial compression test, AE intensity underwent five stages, in which the peak moment of AE intensity exhibited hysteresis compared with the moment of the peak stress. Absorption and release phenomena of strain energy were observed in the process of specimen failure. When the steel slag content increased, the total strain energy absorbed by the specimen increased. When the absorbed energy exceeded the bond strength, the bond ruptured with the release of energy. The main crack of the sample penetrated and stretched to the direction of strain energy release to form a macroscopic fracture surface.

Keywords: Cement-stabilized steel slag; Macromechanics; Microscopic damage mechanism; Parameter sensitivity; Three-dimensional scanning; Uniaxial compression.