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Chai J.,Xi'an University of Science and Technology | Chai J.,Key Laboratory of Western Mine Exploitation and Hazard Prevention | Qiu B.,Xi'an University of Science and Technology | Qiu B.,West Virginia University | And 3 more authors.
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2012

To explore the rock deformation in coal mine by the monitoring of embedded fiber Bragg grating (FBG) through deep borehole, an experimental physical simulation model was built for simulating the strata compression and subsidence process. Additionally, a prefabricate concrete bar with three embedded FBG sensors was designed to simulate deep borehole, and was placed in the physical model. The deformation of the prefabricate concrete bar during strata compression and subsidence processes was measured by the wavelength changes of FBG sensors, and was compared to the strain changes monitored by a resistance strain gauge located on the prefabricate concrete bar at the same location. The test results show that the FBG monitoring system has the advantages of high sensitive, reliable and stable, etc, and can realize the real-time monitoring of rock deformation. It is proved that the FBG monitoring system is an efficient method for measuring and understanding deformation of deep rock strata through a surface borehole.


Zheng F.,Xi'an University of Science and Technology | Lu J.-T.,China Coal Xian Design Engineering Co. | Gao L.,Xian Power Supply Bureau | Yun B.-J.,Xian Xirui Protection and Control Co.
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2010

This paper designs a scheme of redundant network communication based on IEC60870-5-103 transmission protocol and embedded ucLinux platform, which is applied to microcomputer-based relay protection devices. The scheme adopts a pair of Ethernet ports, one of which is the other's standby in hardware design, and makes use of socket programming in Linux system and data sharing or backup to achieve redundant network communication aiming at several host computers in software design. The basic application function of protocol 103 is analyzed, and aiming at the special problem about the application function in redundant network communication, the solutions to the practice of application function are proposed. The application in protection devices indicates that the scheme can improve the reliability of communication.


Chai J.,Xi'an University of Science and Technology | Zhu L.,Xi'an University of Science and Technology | Zhu L.,China Coal Xian Design Engineering Co. | Zhang D.-D.,Xi'an University of Science and Technology | And 5 more authors.
Meitan Xuebao/Journal of the China Coal Society | Year: 2013

To prevent the continuing settlement deformation of unconsolidated strata caused by groundwater dewatering, using the method of the long-term water injection of multi-borehole the settlement deformation of unconsolidated strata was controlled. The fiber Bragg grating sensors was used for the real-time strain monitoring of unconsolidated strata and a mathematical model for the compression settlement induced strain calculation was proposed which can assist understanding the effect of water injection on the ground settlement. Four water wells' (Z2, Z4, Z5, Z6) water injection process in the depth of 138.80-171.40 m, as well as water level monitoring system of four water injection well in the depth of 114.00 to 176.40 m and fiber Bragg grating monitoring system were introduced in this study. With the increase in water injection, unconsolidated strata compressed state is improved by the transition of the stress state from compressive stress to tensile stress. The wavelength change of fiber Bragg grating sensors and the trend of the water level at the same stratigraphic are synchronous. When water injection rate increase for each 1000 m3, the unconsolidated strata increases 1.715 micro-strain. Monitoring results show that it can control the development of the settlement of unconsolidated strata when the water injection quantity for each borehole reaches 3.79-6.00 m3/h and the annual water injection rate reaches 132973.23 m3.


Zhang J.-X.,China University of Mining and Technology | Jiang H.-Q.,China University of Mining and Technology | Miao X.-X.,China University of Mining and Technology | Zhou N.,China University of Mining and Technology | Zan D.-F.,China Coal Xian Design Engineering Co Ltd
Caikuang yu Anquan Gongcheng Xuebao/Journal of Mining and Safety Engineering | Year: 2013

In this paper, we analyzed the surrounding rock deformation features of retained entry and the action mechanism of gob-side support body based on the strata movement characteristics in solid backfill mining. The main factor influencing the deformation and instability of the support body is the lateral force caused by tamping operation. A mechanical model of support body stability influenced by lateral force was established, and the width calculation formula of the support body was deduced. The deformation of the support bodies of different widths was analyzed using numerical simulation method with relevant parameters of Huayuan mine. The result shows that the deformation of the support body can be effectively controlled when its width is more than 2.5 m and it is supported by bolts together with bands and net. The field test proves that the technology is successful and effective; the mechanical model of support body stability as well as the width calculation formula is rational.


Yang Z.,China Coal Xian Design Engineering Co. | Wang J.-D.,Northwest University, China | Lin D.-J.,China Coal Xian Design Engineering Co.
Journal of Natural Disasters | Year: 2011

This paper takes the project example about loess cut side slope along Zhengzhou -Xi' an high-speed Passenger transportation special line as a background, establishes a dynamic analysis computation model of orbital-road-bed-loess side slope by using numerical simulation software FLAC. And disturbed degree and stability of the loess side slope was analyzed for different train-speed. The result indicates that the train speed is faster, the loess side slope perturbation degree is more intense and the stability coefficient of the loess side slope is smaller.


Song Y.-J.,Chang'an University | Lei S.-Y.,Chang'an University | Liu X.-K.,China Coal Xian Design Engineering Co.
Meitan Xuebao/Journal of the China Coal Society | Year: 2012

Rock creep process is the result that the internal stresses of rock constantly adjusts, hardening and damage effect gradually grow and take mutual effect. By means of classic element combination modeling ideas, the rock initial yield strength was regarded as the stress threshold of the creep hardening, and rock's long-term strength served as the stress threshold of damage softening, introduced hardening function and damage variable that could reflect the effect of rock hardening and damage effect. Established nonlinear creep model of rock that could comprehensively reflect the creep mechanism. The fitted results of the test data show that nonlinear rheological model not only can effectively describe the creep process of rocks, but also can reflect creep hardening and damage softening mechanism in the creep process of rocks.


Zhang J.,Xi'an University of Architecture and Technology | Xiao B.,China Coal Xian Design Engineering Co. | Du H.-X.,Xi'an University of Architecture and Technology | Wang L.,Xi'an University of Architecture and Technology | And 2 more authors.
Advanced Materials Research | Year: 2012

Based on emergy theory and calculation methods of emergy values, the environmental support due to pollutants emission was estimated in the DaLiuTa coal mine located in the northern China. The negative effects of waste emission were analyzed from changes of production scale in the mine ecosystem. Moreover, the impacts on environment and potential effects on human health caused by pollutants emission from coal mining wastes were assessed using an index of disability adjusted life years (DALYs) in emergy unit so that sustainability of the mining ecological systems was evaluated on a uniform standard. © (2012) Trans Tech Publications, Switzerland.


Qian S.Z.,China Coal Xian Design Engineering Co.
Applied Mechanics and Materials | Year: 2014

This paper experiments on typical Malan loess, performs consolidated quick direct shear tests under different water contents by conventional direct shear apparatus, then analyzes the effects of water content on shearing strength parameters, namely cohesion and internal friction angle. The results show that cohesion decreases linearly as the water content increasing, and the relation could be obtained by data fitting. However, internal friction angle keeps basically stable with the increase of water content. Finally, based on the force analysis for micro particles, the changing rules of cohesion and internal friction angle with water content were deeply explained. © (2014) Trans Tech Publications, Switzerland.

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