Results 21 to 30 of about 1,853 (153)

Wellbore Breakouts Prediction from Different Rock Failure Criteria

Journal of Engineering, 2020
One of the wellbore instability problems in vertical wells are breakouts in Zubair oilfield. Breakouts, if exceeds its critical limits will produce problems such as loss circulation which will add to the non-productive time (NPT) thus increasing loss in ...
Aows Khalid Neeamy, Nada Sabah Selman
doaj   +1 more source

Analysis of plastic zones in surrounding rocks around a circular tunnel considering the effect of intermediate principal stress and heterogeneity [PDF]

MATEC Web of Conferences, 2019
Based on a modified Mohr-Coulomb criterion with a non-uniform coefficient, a calculation method of plastic zone boundary of surrounding rocks in a circular tunnel in non-uniform stress field is established.
Deng Shuxin, Zheng Yonglai, Feng Lipo, Tuan Le Van, Yue Cuizhou, Wu Zhuorui   +5 more
doaj   +1 more source

Centrifugal loading finite element method for slope stability under damage-seepage coupling effect

Yantu gongcheng xuebao, 2019
An elasto-plastic damage seepage coupling model for rock based on the Mohr-Coulomb criterion is established to analyze slope stability. The stress return method in the principal stress space is given for the Mohr-Coulomb criterion under damage effect to ...
XU Meng-fei 1, JIANG An-nan 1, DUAN Long-mei 2, JIAO Ming-wei 2, HU Xue-feng 2
doaj   +1 more source

Study on fracture parameter calibration and failure characteristics of rock with hole and crack

Deep Underground Science and Engineering, EarlyView.
The SIF and plastic zone equations for a single hole and crack have been derived. The model's failure state leads to the identification of four types of cracks. The plastic zone increases with increased brittleness and decreased crack length. Abstract Cracks within the surrounding rock of roadways significantly affect their stability and failure ...
Shaochi Peng, Wensong Wang
wiley   +1 more source

Temperature‐dependent shear behavior and constitutive model of the rock–concrete interface

Deep Underground Science and Engineering, EarlyView.
Shear tests were conducted to investigate the temperature‐dependent shear behavior of the rock–concrete interface, highlighting the interaction between the surrounding rock and the lining during tunnel fires. Under experimental conditions, concrete exhibited greater temperature sensitivity than rock, with the shear fracture surface transitioning from ...
Hongbin Chen, Yujing Jiang, Rui Pan, Bin Wang, Sunhao Zhang, Jinge Zhang, Xianzhuang Ma   +6 more
wiley   +1 more source

Neural Prediction of Tunnels’ Support Pressure in Elasto-Plastic, Strain-Softening Rock Mass

Applied Sciences, 2018
The prediction of the support pressure (Pi) and the development of the ground reaction curve (GRC) are crucial elements of the convergence–confinement procedure used to design underground structures. In this paper, two different types of artificial
Ali Ghorbani, Hadi Hasanzadehshooiili, Łukasz Sadowski   +2 more
doaj   +1 more source

A Coupled Elastoplastic Damage Model for Clayey Rock and Its Numerical Implementation and Validation

Geofluids, 2020
This paper presents a new constitutive model for describing the strain-hardening and strain-softening behaviors of clayey rock. As the conventional Mohr-Coulomb (CMC) criterion has its limitation in the tensile shear region, a modified Mohr-Coulomb (MMC)
Shanpo Jia, Zhenyun Zhao, Guojun Wu, Bisheng Wu, Caoxuan Wen   +4 more
doaj   +1 more source

Investigation on hard‐rock breaking performance and auxiliary mechanism of picks assisted with both‐sided high‐pressure water jets

Deep Underground Science and Engineering, EarlyView.
This paper investigates the high‐pressure water jet‐pick combined rock‐breaking mode (HPC), which employs high‐pressure water jets to precut grooves on both sides of the picks. The rock‐breaking patterns and performance of the HPC method are obtained, and the auxiliary rock‐breaking mechanism of water jet grooving is revealed.
Jingjing Lu, Jiancheng Xiao, Hui Zhou, Xiao Ma, Congcong Hou, Jian Cui, Fujian Yang   +6 more
wiley   +1 more source

Generalized Matsuoka–Nakai criterion considering hydrostatic pressure dependence in the brittle–ductile region

Deep Underground Science and Engineering, EarlyView.
Three sets of strength data were selected, including hydrostatic pressure independent within the brittle region (HPI‐B), hydrostatic pressure dependent within the brittle region (HPD‐B), and hydrostatic pressure dependent within the brittle–ductile region (HPD‐BD). For HPI type, the failure envelope within the deviatoric plane remains constant.
Jiacun Liu, Junjie Xiao, Dongping Liu, Ying Xu   +3 more
wiley   +1 more source

Slip versus dilation tendency parameter space as a tool for prospecting structurally controlled geothermal systems in greenfield: insights from the greater Ruhr region

Deep Underground Science and Engineering, EarlyView.
This study highlights that with the static and time‐dependent evolution of slip versus dilation tendency parameter space, structurally controlled deep geothermal systems can be selected within areas of higher permeability and lower seismic hazard. Abstract Faults play a vital role in the Earth's hydraulic system by facilitating fluid flow when dilating
Michal Kruszewski, Alessandro Verdecchia, Oliver Heidbach, Rebecca M. Harrington, David Healy   +4 more
wiley   +1 more source