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Zheng J.,Yanshan University | Sun H.,China Railway Shanhaiguan Bridge Group Co. | Jiang C.,Third railway survey and design institute group corporation
2011 International Conference on Multimedia Technology, ICMT 2011 | Year: 2011

Transverse vibrations of bridges stirred by train affect the bridge's safety and comfort of the train. For simply supported beam, the paper deduces the response of the beam under a fixed harmonic load, uniform constant load or uniform moving harmonic load. The conclusion is that the response of the beam under uniform moving harmonic load is only about half of the response under a fixed harmonic load, which makes it reasonable that the train translates into a fixed harmonic load. Then a simplified analysis method of the bridge's vibration is obtained. The Example shows the feasibility of this simplified analysis. © 2011 IEEE. Source

Ma H.,Dalian Jiaotong University | Lu G.-Q.,China Railway Shanhaiguan Bridge Group Co. | Zhang J.,Dalian Jiaotong University
Dongbei Daxue Xuebao/Journal of Northeastern University | Year: 2013

The finite element method is applied to solve the wheel-frog contact problem existing in the Datong-Qinhuangdao line. Several wheel-frog contact models with different standard were established, and the standard rail section using the 75 kg/m rail. The elastic-plastic calculation was carried out to analyze the distribution and change laws of the von Mises stress and contact patch. When the wheels pass the frog, the contact paths and ride comfort were also analyzed. The results show that the contact patch of wheel and frog is narrow and long. The von Mises stress is larger than material yield strength and makes the wheel and frog enter the plastic deformation stage, which causes serious wheel-frog abrasion. The von Mises stress at 360~480 mm distance from theoretical nose has larger change. When the wheel with standard profile runs from worn frog wing rail to point rail, the contact patch in point rail is ahead of that in wing rail in the longitudinal direction. It makes the rolling radius difference of different contact point become large and causes serious wheel-frog abrasion. The wheels pass the standard frog smoothly, while the wheel has large vertical displacement when passing worn frog which makes the wheel-frog impact. The research provides a certain theoretical basis for the antifriction measures and design of wheel and frog used in the heavy haul railway. Source

Wang X.-R.,China Railway Shanhaiguan Bridge Group Co. | Zhang Y.,University of Sichuan | Liu Y.,General Research Institute for Nonferrous Metals, China | Yan J.-T.,The Forth Company of 404 Company Ltd
Yejin Fenxi/Metallurgical Analysis | Year: 2015

The standard sample of microalloy was used as an example to collect the whole-spectrum data by laser-induced breakdown spectroscopy technique. The application of Origin 9.0 software in data processing in plasma emission spectrum analysis (such as the deduction of spectral background, the fitting of spectral profile fitting and multiple overlapping peaks) was introduced detailedly. Al(I) 396.152 nm was used for Lorentz fitting. Some important information including peak area, the peak width at half height and peak height could be obtained by the Lorentz fitting curve. Based on the peak width at half height and the simplified Stark field broadening formula, the electron number density in plasma was estimated, i. e., 2.74×1016 cm-3. In addition, the spectral interference of triple overlapped and undivided peaks of Mn element at 402.8-403.8 nm was corrected by the multiple-peak fitting function. The parameter information such as fitting function was also provided. The quantitative analysis could be conducted according to the peak height and peak area. © 2015, Central Iron and Steel Research Institute. All right reserved. Source

Sun J.-L.,Yanshan University | Liu H.-M.,Yanshan University | Li Y.-Y.,China Railway Shanhaiguan Bridge Group Co. | Peng Y.,Yanshan University
Kang T'ieh/Iron and Steel | Year: 2015

The horizontal vibration mechanism of hot tandem rolling mill was studied, and the relationship between the horizontal vibration and the rolling process parameters was obtained. Considering the gap between the bearing chock and the housing, the offset of work roll and backup roll, and the nonlinear damping, the nonlinear dynamic model of horizontal vibration of strip rolling mill was established, and the relationship model of horizontal vibration and rolling process parameters was also established. Then, the online horizontal vibration test was carried out on the F2 rolling mill of some steel plant. The test result shows that the horizontal vibration of the work roll is very strong, with an amplitude up to 4.5 g in the middle and later periods and more than 5 g at the end phase, and the main vibration frequencies are 40 Hz and 118 Hz. At the same time, based on the model established, the vibration simulation in the rolling process was made to investigate the effect of strip thickness, rolling speed and tensile stress on horizontal vibration. The simulation results show that: the acceleration amplitude of horizontal vibration is 4.8 g in the simulation, which agrees with the measured results, thus validating the model established. When the strip thickness is thinner, the influence on the horizontal vibration is larger; the influence of rolling speed on the horizontal vibration is strong, and the influence of tension on the horizontal vibration is small compared to other factors. ©, 2014, Chinese Society for Metals. All right reserved. Source

Liu M.-H.,China Communications Construction Company Ltd. | Sun P.,China Communications Construction Company Ltd. | Hu G.-R.,China Railway Shanhaiguan Bridge Group Co. | Li G.-L.,China Communications Construction Company Ltd.
Bridge Construction | Year: 2016

The Qingzhou Ship Channel Bridge of the Hong Kong-Zhuhai-Macao Bridge is a double-pylon cable-stayed bridge and the pylons of the bridge are the reinforced concrete frame structures. Through careful study of the architectural landscape effect of the bridge, the bracing system connecting the columns of a pylon of the bridge is designed into the "Chinese Knot" style cross bracing of steel structure (hereinafter referred to as the knot style bracing). The shape of the knot style bracing is irregular, the dimensions are large and the design, manufacturing and installation of the bracing are difficult and technically complex. The section of the bracing is the box section of variable depth and with rounded corners. When the bracing is connected with the concrete columns, the combined force transmission way of the "compression bearing-shear transferring" and the connecting boxes are applied. The interior and exterior surfaces of the bracing are protected by the paint coating system and the bracing is also provided with the all-directional maintenance accesses and maintenance facilities. The structural calculation and analysis show that the force conditions of the knot style bracing are safe. The bracing is manufactured and installed in segments. In the manufacturing, special measures have been taken to ensure the global shape of the bracing and in the installation, the pre-embedded segments and bracing segments are installed respectively. © 2016, Wuhan Bridge Research Institute. All right reserved. Source

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