Results 31 to 40 of about 9,272 (117)

Static and dynamic mechanical properties and macro-micro coalburst prevention mechanisms of water-immersed coal

Meitan kexue jishu
Hydration weakens the macro-mesoscopic mechanical properties of burst-prone coal, enhances the stress wave energy reflection-refraction capability of the coal, and reduces the risk of impact energy release in water-injected roadways.
Aiwen WANG, Dewei FAN, Yishan PAN, Lianpeng DAI, Chaoran LI, Kailei YANG, Wei ZHANG, Xingfa LIU, Hanqi LIU, Chuang LU   +9 more
doaj   +1 more source

Experimental Investigation and Mechanism Analysis on Rock Damage by High Voltage Spark Discharge in Water: Effect of Electrical Conductivity

Energies, 2020
High voltage spark discharge (HVSD) could generate strong pressure waves that can be combined with a rotary drill bit to improve the penetration rate in unconventional oil and gas drilling.
Zhixiang Cai, Hui Zhang, Kerou Liu, Yufei Chen, Qing Yu   +4 more
doaj   +1 more source

Fracture mechanism of granite under the combined action of high voltage electric pulse and high stress

Meitan xuebao
The fracture mechanism of granite under the combined action of unidirectional static stress and high voltage electric pulse is systematically studied by means of experiment and numerical simulation.
Yuelang GUO, Fengpeng ZHANG, Jikai GAO, Yuanhang ZHOU, Chuanyi LIU, Qiqi HAO   +5 more
doaj   +1 more source

Effect of Aggregate Gradation on Reducing Reflection Crack

Journal of Engineering and Sustainable Development, 2010
e rehabilitation of cracked flexible pavement roads by overlaying, without any improvement, is rarely a durable solution, as the cracks rapidly propagate through the new asphalt layer.
Qais S. Kareem
doaj  

Using borehole radar detecting hydraulic fracturing crack in near horizontal holes in coal mine

Frontiers in Earth Science
Currently, hydraulic fracturing technology is widely implemented for controlling the surrounding rock and enhancing permeability in low-permeability coal seams.
Jiang Bici, Jiang Bici
doaj   +1 more source

Presenting a Statistical Model of Fatigue Prediction for the Effect of Loading Frequency on Reflective Cracks Propagation on Asphalt Layers Improved by Geosynthetics [PDF]

Journal of Rehabilitation in Civil Engineering
So far, several methods have been proposed for delaying the reflective cracks in pavements. Despite substantial money spent annually on these types of maintenance methods to control reflection cracking in road pavement, none of them has successfully ...
Saeid Asadi, Gholamali Shafabakhsh
doaj   +1 more source

Analysis of the Fatigue Crack Propagation Process of the Stress-Absorption Layer of Composite Pavement Based on Reliability

Applied Sciences, 2018
The stress-absorption layer in cement concrete pavement delays the development of reflection cracks and is good at fatigue resistance. Laboratory investigations of the anti-crack performance of the high viscous asphalt sand stress-absorption layer ...
Yazhen Sun, Ting Yan, Changyu Wu, Xiaofang Sun, Jinchang Wang, Xuezhong Yuan   +5 more
doaj   +1 more source

Forward Simulation and Complex Signal Analysis of Concrete Crack Depth Detection Using Tracer Electromagnetic Method

Buildings
Cracks are the most typical faults of concrete structures, and their extension can lead to structural fracture. However, when cracks develop inside a structure, the most important depth information is invisible and difficult to measure.
Yulei Wang, Shengxing Zhang, Yu Jia, Lei Tang, Jin Tao, Hui Tian   +5 more
doaj   +1 more source

CRACKS IN ROADWAY COVERING: METHODS FOR IMPROVEMENMT OF CRACK RESISTANCE

Наука и техника, 2011
Crack formation is presently considered as an actual problem in the global practice. The paper provides various approaches pertaining to improvement of asphalt-concrete composition with the purpose to prevent formation of temperature and fatigue cracks ...
I. I. Leonovich, I. S. Melnikova
doaj  

Influence of notch hole wall defects on crack propagation under notch blasting

Baozha yu Chongji
The defective cracks were prefabricated on the wall of the notch holes by using polymethyl methacrylate (PMMA) material, which were parallel or vertical to the notch, and the distance from the defective cracks to the hole center was 2, 3, and 4 mm.
Yuhang CHENG, Feng LIU, Wei DAI, Zhengde ZHU, Rujie BI, Changxin PAN   +5 more
doaj   +1 more source