Peridynamic investigation on crack propagation mechanism of rock mass during excavation of tunnel group in cold regions

Abstract

An extended ordinary state-based peridynamic model was developed to investigate the crack propagation of surrounding rock due to tunnel excavation. The frost heave effect on the crack surface was described by an equivalent pressure density. Two numerical examples were conducted to verify the effectiveness and robustness of the proposed model. Moreover, the influence of frost heave pressure, buried depth and rock elastic modulus on damage characteristics of the surrounding rock was investigated. The results demonstrate that massive microcrack damage will be formed at the invert when the tunnel is excavated in a deeply buried rock mass or soft rock stratum.

HIGHLIGHTS

• A peridynamic model of rock mass under excavation and frost heave was constructed.

• Damage characteristics of surrounding rock could be simulated efficiently.

• Frost heave load was exerted on the crack surface by an equivalent pressure density.

• The effects of frost heave load, buried depth and rock elastic modulus were studied.

Keywords:

• Ordinary state-based peridynamics
• rock mass
• crack propagation
• frost heave pressure
• cold region tunnels
• excavation damage zone

Disclosure statement

The authors report there are no competing interests to declare.

Additional information

Funding

This work was supported by the Fundamental Research Funds for the Central Universities (No. 2242022k30062), and the National Natural Science Foundation of China (No. 51578142).