Modeling and simulation of dynamic unloading of prestressed rockmass

Liang Wu, Xiaorui Xiang, Yang Chen, Karrech Ali, Junru Zhou, Ming Chen

Research output: Contribution to journalArticle

Abstract

During the excavation of deep rock, a sudden change in boundary conditions will cause the in-situ stress on the excavation surface to release instantaneously. This disturbance propagates in the form of an unloading stress wave, which will enlarge the damage field of surrounding rock. In this paper, the dynamic unloading problem of the in-situ stress in deep rock excavation is studied using theoretical, numerical, and experimental methods. First, the dynamic unloading process of rock is analyzed through adopting the wave equation, and the equivalent viscous damping coefficient of the material is taken into consideration. Calculations show that there is significant tensile strain in the rock bar when the strain rate is above 10-1 s-1. With an increase in the length or damping coefficient, the wave state will change from an underdamped to an overdamped state. Second, implicit and explicit solvers of the finite element method are employed to simulate rock unloading processes, which can be used to verify the theoretical results from one-dimensional to three-dimensional stress states. Finally, the dynamic unloading experiment of a one-dimensional bar is used to further verify the validity and accuracy of the theoretical analysis.

Original languageEnglish
Pages (from-to)421-443
Number of pages23
JournalCMES - Computer Modeling in Engineering and Sciences
Volume120
Issue number2
DOIs
Publication statusPublished - 1 Jan 2019

Fingerprint

Unloading
Modeling and Simulation
Rocks
Damping
Excavation
Verify
Stress Wave
Dynamic Process
Strain Rate
Dynamic Problem
Coefficient
Wave equation
Theoretical Analysis
Damage
Disturbance
Finite Element Method
Boundary conditions
Three-dimensional
Tensile strain
Wave equations

Cite this

Wu, Liang ; Xiang, Xiaorui ; Chen, Yang ; Ali, Karrech ; Zhou, Junru ; Chen, Ming. / Modeling and simulation of dynamic unloading of prestressed rockmass. In: CMES - Computer Modeling in Engineering and Sciences. 2019 ; Vol. 120, No. 2. pp. 421-443.
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Modeling and simulation of dynamic unloading of prestressed rockmass. / Wu, Liang; Xiang, Xiaorui; Chen, Yang; Ali, Karrech; Zhou, Junru; Chen, Ming.

In: CMES - Computer Modeling in Engineering and Sciences, Vol. 120, No. 2, 01.01.2019, p. 421-443.

Research output: Contribution to journalArticle

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