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Li C.-Y.,Xian University of Architecture and Technology | Zhou Q.-H.,Xian University of Architecture and Technology | Lu M.-X.,Xian Municipal Engineering Design and Research Institute Co. | Zhu T.,Changan University
Chang'an Daxue Xuebao (Ziran Kexue Ban)/Journal of Chang'an University (Natural Science Edition) | Year: 2014

This paper is aimed at building the model of non-motorized accessibility to evaluate urban planning or transportation planning scheme. Using the energy consumption as the accessibility impedance, this paper established multi-section impedance function, and the non-motor vehicle traffic accessibility mathematical model (NABE model). Comparing the various accessibility model calculation results, this paper found that NABE model could embody the influence of the motorized traffic facilities on non-motor vehicle traffic circle. When impedance increases, NABE accessibility model can reflect the trends of accessibility changing; When impedance is close to zero, this model can also express non-motor vehicle traffic accessibility under extreme condition. The characteristics above make up for problems of the traditional model in describing the non-motor vehicle traffic accessibility. In brief, if's mone reasonable to apply NABE model to the evaluation of traffic planning scheme. Source

Like Q.,Xian University of Science and Technology | Jun D.,Xian University of Science and Technology | Juntian Z.,Xian Municipal Engineering Design and Research Institute Co.
Electronic Journal of Geotechnical Engineering | Year: 2015

The research on the temperature inside the rock and the characteristics of the distribution and evolution of stress can not only contribute to the understanding of the mechanism of the microwave assisted rock breakage, but also provide scientific basis for the designing of microwave devices. The study takes the wave-absorbing pyrite and the wave-transparent calcite as the object of study, adopts finite element technique to calculate the temperature distribution and stress distribution of the rock particles, and considers the impact of irradiation time, power density, and particle size. The result shows that under different irradiation time, temperature distributions of the rock particles are similar. The temperature inside the pyrite changes little, while the temperature of calcite decreases in a hyperbolic curve from inside to outside. The stress concentration phenomenon exists in the conjunction of minerals. The greater the temperature gradient is, the higher the thermal stress is in the conjunction of minerals. The microwave of higher power can create greater temperature gradient and higher thermal stress inside the rock within extremely short irradiation time. Therefore, it is suggested to use high-power microwave in the microwave assisted rock breaking. When the size of the rock is fixed, the smaller the pyrite crystal is, the smaller the temperature gradient is, the lower the thermal stress is, and the more difficult the rock breaking is. © 2015 ejge. Source

Zhou Y.-C.,Changan University | Hu S.-N.,North China University of Water Conservancy and Electric Power | Song L.,Xian Municipal Engineering Design and Research Institute Co. | Li Z.-Q.,North China University of Water Conservancy and Electric Power
Jiaotong Yunshu Gongcheng Xuebao/Journal of Traffic and Transportation Engineering | Year: 2013

The temperatures of steel-concrete composite beam cross-sections under nature condition were tested, the formulae of steel-concrete composite beam interfacial shear force, shear stress, relative slide strain and deformation, flexural deformation curvature were derived by using temperature gradient calculation model and elastic theory. Analysis result shows that there is temperature difference in the cross-section, and the temperature distribution of concrete flange slab is uneven. The maximum interfacial shear force is at the midspan and decreases to zero at the end of beam. The maximum interfacial shear stress, relative slide strain and deformation are at the end of beam and decrease to zero at the midspan. Interfacial force and deformation are linearly proportional to temperature difference, and the slope is associated with the temperature distribution modes of concrete slab. The temperature distribution mode and thickness of concrete slab are the main influence factors of interfacial force and deformation. Source

Pei J.-Z.,Changan University | Chen Y.,Xian Municipal Engineering Design and Research Institute Co. | Wang B.-G.,Changan University
Zhongguo Gonglu Xuebao/China Journal of Highway and Transport | Year: 2011

In order to analyze dynamic response characteristics of asphalt pavement under multi-axle moving load, a three-dimensional finite element model of asphalt pavement was established by field investigation. The influences of axle load with uniform distribution of single rear axle, dual rear axles and three rear axles and the axle load with non-uniform distribution of three rear axles and the three rear axles vehicles with impending front axle on pavement were studied respectively. Results show that the effect of each axle on pavement is independent when the wheelbase of multi-axle vehicle is bigger than 3 m. Increase of number of axle makes the vertical displacement of pavement superpose and makes the maximal shear stress and compressive stress of pavement change inconspicuously. The influence of the middle axle of three rear axles vehicle on the vertical displacement of pavement is the greatest which increases by 23.7% and 18.2% compared with those of the front axle and rear axle respectively. Besides, the middle axle and rear axle has certain influence on the shear stress of pavement, but each axle has almost no influence on the maximal compressive stress of pavement. The research results indicate that the non-uniform distribution of axle load of multi-axle vehicle has significant influence on pavement failure. Source

Chen J.,Changan University | Chen J.,Xian Municipal Engineering Design and Research Institute Co. | Yang S.-W.,Changan University
Xi'an Jianzhu Keji Daxue Xuebao/Journal of Xi'an University of Architecture and Technology | Year: 2011

Vehicles of 4-direction streams wanting to pass the double-crossing continuously must choose different way according to the information from the display monitor. It is discovered that running rate V85, the path top rake, reaction time of driver, the distance from the branch end to the stop line as well as vehicles' characteristics are important factors affecting the opportunity of information conversion. Obtained through the computation analysis, regardless of the choice of the upper crossing or the lower crossing, the opportunity determining the information conversion is the same, i.e., the vehicles arriving at the stop line can pass the crossing continuously if the green time is also left over time T, and after the information display monitor's information changes, the vehicles choose in the T time through the upper formation way just right travel to the upper stop line, while the upper formation's green light opening at that time(necessary to wait while the information light turning from green to red if the lower way was adopted). Source

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