Results 141 to 150 of about 63,012 (308)

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

Failure characteristics and the energy criterion of rock with a through‐going joint under true‐triaxial unloading conditions: Insights from the DEM model

Deep Underground Science and Engineering, EarlyView.
The rock failure mode is significantly influenced by the contributing factors, such as the joint inclination, the initial confining pressure, and the unloading point. We found six typical rock failure modes after a large number of numerical tests. Abstract Excavation unloading damages rock masses, with preferential failure along geological defects in ...
Fei Liu, Changhui Liang, Sijia Liu, Yongjun Zhang, Luo Wang   +4 more
wiley   +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

Review and prospects of shear test of bolted rock joints

Deep Underground Science and Engineering, EarlyView.
The laboratory shear test equipment, test method, and numerical simulation of bolted rock joints were summarized. The shortcomings and limitations of the current research were analyzed, and the research prospects were proposed. Abstract Rock bolting is a critical approach in geotechnical engineering for supporting weak rocks.
Shulin Ren, Fan Yang, Manchao He, Yong Yuan, Zhigang Tao   +4 more
wiley   +1 more source

Application of traction drives as servo mechanisms [PDF]

The suitability of traction drives for a wide class of aerospace control mechanisms is examined. Potential applications include antenna or solar array drive positioners, robotic joints, control moment gyro (CMG) actuators and propeller pitch change ...
Loewenthal, S. H., Rohn, D. A., Steinetz, B. M.   +2 more
core   +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

The damage and failure mechanism of prestatically loaded rock during medium‐strain rate cyclic impact loading

Deep Underground Science and Engineering, EarlyView.
Based on experimental results and theoretical analysis, an established rock damage accumulation model that comprehensively considers the preapplied static load, impact peak value, impact frequency, and impact times. Abstract To study the rock damage mechanism under high static loading and superimposed medium strain rate cyclic impact loading, a series ...
Wei Wang, Hanpeng Wang, Zicheng Wang, Xinyuan Xie, Yunhao Wu, Jinhou Zhang, Dekang Sun   +6 more
wiley   +1 more source

Critical expansion points: Mechanical signs of surrounding rock instability

Deep Underground Science and Engineering, EarlyView.
This study proposes the Rock Bearing‐Expansion Model (RockBEM) with critical expansion points (CEPs) to quantify post‐peak damage stages in deep‐buried rock masses via plane strain compression test (PSCT). CEP hysteresis&interval ratios reveal bearing performance dynamics and failure severity, advancing mechanistic insights into deep underground rock ...
Jiaqi Wen, Chang Deng, Haijun Wang, Lei Tang, Jihong Yu   +4 more
wiley   +1 more source

Study of the energy efficiency of various drive systems of an innovative implantable left ventricular assist device. [PDF]

Sci Rep
Jasinski R, Tesch K, Dabrowski L, Rogowski J.   +3 more
europepmc   +1 more source

Multiple injection techniques to stimulate complex fracture networks in coal reservoirs: A case study on gas disaster reduction of subsurface coal mine in southwest China

Deep Underground Science and Engineering, EarlyView.
An experimental device for physical simulation of hydraulic fracturing, comprising: a load‐bearing mechanism with multiple interconnected plates that collectively form an sample chamber; a load‐generating mechanisms, with multiple load‐generating mechanisms arranged within the experimental chamber.
Delei Shang, Farui Shi, Jun Lu, Minghui Li, Cunbao Li, Heping Xie   +5 more
wiley   +1 more source