Results 31 to 40 of about 2,122 (176)

Experimental study of mechanical properties of highly-stressed rocks under true triaxial unloading conditions with different unloading directions

Shuiwen dizhi gongcheng dizhi
During the excavation process of deep rock masses, the surrounding rock stress field forms alternating zones of stress increase (loading zones) and stress decrease (unloading zones) near the excavation surface, which can easily trigger instability and ...
Qian XIANG, Ke WANG, Lei WENG, Weijun YOU, Zhaofei CHU, Zeyu LI   +5 more
doaj   +1 more source

Cryogenic Fracturing of Wellbores Under True Triaxial-Confining Stresses: Experimental Investigation [PDF]

SPE Journal, 2018
Summary A laboratory study of cryogenic fracturing was performed to test its ability to improve oil/gas recovery from low-permeability reservoirs. Our objective is to develop well-stimulation technologies using cryogenic fluids [e.g., liquid nitrogen (LN)] to increase permeability in a large reservoir volume surrounding wells.
Cha, Minsu, Alqahtani, Naif B, Yao, Bowen, Yin, Xiaolong, Kneafsey, Timothy J, Wang, Lei, Wu, Yu-Shu, Miskimins, Jennifer L   +7 more
openaire   +3 more sources

Mechanical parameter evolutions and deterioration constitutive model for ductile–brittle failure of surrounding rock in high-stress underground engineering

Underground Space
The deep surrounding rock is usually in the true triaxial stress state, and previous constitutive models based on the understanding of uniaxial and conventional triaxial test results have difficulty characterizing the degradation and fracture process of ...
Zhi Zheng, Ronghua Li, Qiang Zhang, Xiaohua Huang, Wei Wang, Shuling Huang   +5 more
doaj   +1 more source

Research on the mechanical characteristics of granite failure process under true triaxial stress path

Rock and Soil Mechanics, 2021
The true triaxial loading and unloading tests on granite were conducted to obtain the mechanical characteristics of the granite in the construction area of an underground cavern.
LIU Jie, ZHANG Li-ming, CONG Yu, WANG Zai-quan   +3 more
doaj   +1 more source

3D (Bio) Printing Combined Fiber Fabrication Methods for Tissue Engineering Applications: Possibilities and Limitations

Advanced Functional Materials, EarlyView.
Biofabrication aims at providing innovative technologies and tools for the fabrication of tissue‐like constructs for tissue engineering and regenerative medicine applications. By integrating multiple biofabrication technologies, such as 3D (bio) printing with fiber fabrication methods, it would be more realistic to reconstruct native tissue's ...
Waseem Kitana, Indra Apsite, Leonid Ionov   +2 more
wiley   +1 more source

Effect of true triaxial principal stress unloading rate on strain energy density of sandstone

Scientific Reports
Deep rock are often in a true triaxial stress state. Studying the impacts of varying unloading speeds on their strain energy (SE) density is highly significant for predicting rock stability.
Zhixi Liu, Guangming Zhao, Xiangrui Meng, Qingheng Gu   +3 more
doaj   +1 more source

True triaxial tests on unsaturated soils with suction-controlled condition

Yantu gongcheng xuebao, 2019
Based on the new true triaxial apparatus of Xi’an University of Technology, the pedestal of the pressure chamber is installed with a high-air-entry-value ceramic disk and porous plate is placed on the top of the specimens.
ZHENG Fang 1, SHAO Sheng-jun 1,2, ZHANG Bo 1, SHE Fang-tao 1
doaj   +1 more source

Probability prediction of true‐triaxial compressive strength of intact rocks based on the improved PSO‐RVM model

Deep Underground Science and Engineering, EarlyView.
In this work, we propose an improved particle swarm optimization (PSO) algorithm and develop an improved PSO‐relevance vector machine (RVM) model as a substitute for traditional true‐triaxial testing. The model's high prediction accuracy was validated through comparisons with two other machine learning methods and five three‐dimensional Hoek–Brown type
Qi Zhang, Maohui Wang, Ning Wang, Yixin Shen, Xuzhen He   +4 more
wiley   +1 more source

A multifunctional shear apparatus for rocks subjected to true triaxial stress and high temperature in real-time

Journal of Rock Mechanics and Geotechnical Engineering
Deep engineering disasters, such as rockbursts and collapses, are more related to the shear slip of rock joints. A novel multifunctional device was developed to study the shear failure mechanism in rocks. Using this device, the complete shear–deformation
Jun Zhao, Xia-Ting Feng, Jia-Rong Wang, Liang Hu, Yue Guo   +4 more
doaj   +1 more source

Effect of confining pressure on fracture characteristics and mineralogical behavior of tight sandstone specimens after hydraulic fracturing

Deep Underground Science and Engineering, EarlyView.
Hydraulic fracturing in tight sandstone and fracture propagation characteristics using backscattered electron‐scanning electron microscope (BSE‐SEM) images. Abstract This study focuses on hydraulic fracturing experiments conducted under triaxial conditions on tight sandstone specimens from Shivpuri district, Madhya Pradesh, India.
Pankaj Rawat, Narendra Kumar Samadhiya
wiley   +1 more source