Dynamic Performance Analysis on High-Speed Railway Continuous Girder Bridge

2011 ◽  
Vol 280 ◽  
pp. 186-190
Author(s):  
Shou Tan Song ◽  
Ji Wen Zhang ◽  
Xin Yuan
Keyword(s):  
High Speed ◽  
Moving Load ◽  
Damping Ratio ◽  
Dynamic Performance ◽  
Wheel Load ◽  
Dynamic Coefficients ◽  
Bridge Structures ◽  
Continuous Girder Bridge ◽  
Girder Bridge ◽  
Dynamic Performance Analysis

The dynamic performance of continuous girder under the train in a series of speed is studied through examples, and the main conclusions are given in the following. The resonance mechanism of continuous girder is similar to simply supported beam. The vehicle wheel load forms regular moving load series, which induces periodical action and resonance of the bridge. The damping ratio of bridge itself has less effect on the amplitude at the loading stage, but significant effects appear when the load departs from the bridge. The count of continuous spans also has less impact on the dynamic coefficients, so three continuous spans can be adopted for calculation and analysis. Span and fundamental frequency have significant influence on dynamic coefficients of bridge structures. To extend the span of the bridge structure can reduce the dynamic coefficient while keeping its frequency invariant. The fundamental frequencies of different bridges are corresponding to certain resonant speeds, which calls for the attention in the design.

Dynamic interaction between the two-axle vehicle and continuous girder bridge with considering vehicle braking force

2014 ◽  
Vol 36 (1) ◽  
pp. 49-60 ◽  
Author(s):  
Nguyen Xuan Toan
Keyword(s):  
High Speed ◽  
Rapid Development ◽  
High Strength ◽  
Dynamic Interaction ◽  
Inertia Force ◽  
Bending Vibration ◽  
Girder Bridges ◽  
Bridge Structures ◽  
Continuous Girder Bridge ◽  
Girder Bridge

Nowadays, the structures of continuous girder bridges are becoming more and more popular with the rapid development of highway networks in many nations around the world, including Vietnam. High strength materials are commonly used to construct the bridge structures, so they are very slender and sensitive to the effects of dynamic loads, especially in the cases that vehicles run with high speed or brake suddenly on the bridges. In this paper, the author would like to introduce the study of a model of dynamic interaction between two-axle vehicle and continuous girder bridge. The model of a two-axle vehicle consists of three masses, taking into account the inertia force and friction force between the tires and the bridge surface due to vehicle braking. Vertical reaction forces of axles which change with time make bending vibration of beam increase significantly. The results of the experiment on the Hoaxuan Bridge and the analysis of the computerized model indicate that dynamic factors are substantial when vehicle brakes suddenly on bridge.

Structure design and dynamic performance analysis of a high speed miniature lathe

2013 ◽  
Vol 9 (2) ◽  
pp. 119
Author(s):  
Hua dong Yu ◽  
Li meng Wang ◽  
Xiao zhou Li ◽  
Jin kai Xu ◽  
Qing yong Shi
Keyword(s):  
Performance Analysis ◽  
High Speed ◽  
Dynamic Performance ◽  
Structure Design ◽  
Dynamic Performance Analysis

scholarly journals Measurement Research of Motorized Spindle Dynamic Stiffness under High Speed Rotating

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Xiaopeng Wang ◽  
Yuzhu Guo ◽  
Tianning Chen
Keyword(s):  
High Speed ◽  
Production Efficiency ◽  
Dynamic Stiffness ◽  
Damping Ratio ◽  
Dynamic Performance ◽  
Machining Accuracy ◽  
Motorized Spindle ◽  
Response Curves ◽  
Tool Technology ◽  
High Speed Machine

High speed motorized spindle has become a key functional unit of high speed machine tools and effectively promotes the development of machine tool technology. The development of higher speed and more power puts forward the stricter requirement for the performance of motorized spindle, especially the dynamic performance which affects the machining accuracy, reliability, and production efficiency. To overcome the problems of ineffective loading and dynamic performance measurement of motorized spindle, a noncontact electromagnetic loading device is developed. The cutting load can be simulated by using electromagnetic force. A new method of measuring force by force sensors is presented, and the steady and transient loading force could be measured exactly. After the high speed machine spindle is tested, the frequency response curves of the spindle relative to machine table are collected at 0~12000 rpm; then the relationships between stiffness and speeds as well as between damping ratio and speeds are obtained. The result shows that not only the static and dynamic stiffness but also the damping ratio declined with the increase of speed.

Analysis on Dynamic Performance of Hydrodynamic Tilting-Pad Gas Bearings Using Partial Derivative Method

2008 ◽  
Vol 131 (1) ◽  
Author(s):  
Yang Lihua ◽  
Qi Shemiao ◽  
Yu Lie
Keyword(s):  
Analytical Method ◽  
Gas Turbines ◽  
High Speed ◽  
Dynamic Performance ◽  
Gas Bearings ◽  
Dynamic Coefficients ◽  
Tilting Pad ◽  
Dynamic Performances ◽  
Perturbation Frequency ◽  
San Andres

Tilting-pad gas bearings are widely used in high-speed rotating machines due to their inherent stability characteristics. This paper advances the analytical method for prediction of the dynamic performances of tilting-pad gas bearings. The main advantage of the analytical method is that the complete set of dynamic coefficients of tilting-pad gas bearings can be obtained. The predictions show that the perturbation frequency has the strong effects on the dynamic coefficients of gas bearings. In general, at lower perturbation frequency, the equivalent direct stiffness coefficients increase with frequency, whereas equivalent direct damping coefficients dramatically reduce. For higher perturbation frequency, the dynamic coefficients are nearly independent of the frequency. Moreover, the equivalent dynamic coefficients of four-pad tilting-pad gas bearing obtained by the method in this paper are in good agreement with those obtained by Zhu and San Andres [(2007), “Rotordynamic Performance of Flexure Pivot Hydrostatic Gas Bearings for Oil-Free Turbomachinery,” ASME J. Eng. Gas Turbines Power, 129(4), pp. 1020–1027] in the published paper. The results validate the feasibility of the method presented in this paper in calculating the dynamic coefficients of gas-lubricated tilting-pad bearings.

scholarly journals High-Speed Train-Track-Bridge Dynamic Interaction considering Wheel-Rail Contact Nonlinearity due to Wheel Hollow Wear

2019 ◽  
Vol 2019 ◽  
pp. 1-18 ◽  
Author(s):  
Chao Chang ◽  
Liang Ling ◽  
Zhaoling Han ◽  
Kaiyun Wang ◽  
Wanming Zhai
Keyword(s):  
High Speed ◽  
Synthesis Method ◽  
Dynamic Interaction ◽  
High Speed Train ◽  
Train Track ◽  
High Speed Railway ◽  
Long Span ◽  
Continuous Girder Bridge ◽  
Girder Bridge ◽  
Track Bridge

Wheel hollow wear is a common form of wheel-surface damage in high-speed trains, which is of great concern and a potential threat to the service performance and safety of the high-speed railway system. At the same time, rail corridors in high-speed railways are extensively straightened through the addition of bridges. However, only few studies paid attention to the influence of wheel-profile wear on the train-track-bridge dynamic interaction. This paper reports a study of the high-speed train-track-bridge dynamic interactions under new and hollow worn wheel profiles. A nonlinear rigid-flexible coupled model of a Chinese high-speed train travelling on nonballasted tracks supported by a long-span continuous girder bridge is formulated. This modelling is based on the train-track-bridge interaction theory, the wheel-rail nonelliptical multipoint contact theory, and the modified Craig–Bampton modal synthesis method. The effects of wheel-rail nonlinearity caused by the wheel hollow wear are fully considered. The proposed model is applied to predict the vertical and lateral dynamic responses of the high-speed train-track-bridge system under new and worn wheel profiles, in which a high-speed train passing through a long-span continuous girder bridge at a speed of 350 km/h is considered. The numerical results show that the wheel hollow wear changes the geometric parameters of the wheel-rail contact and then deteriorates the train-track-bridge interactions. The worn wheels can increase the vibration response of the high-speed railway bridges.

Finite Element Analysis and Optimization of Structure for Large Blanking Machine Equipment during High-Speed Blanking

2011 ◽  
Vol 697-698 ◽  
pp. 176-181
Author(s):  
Shu Bo Xu ◽  
K.K. Sun ◽  
Cai Nian Jing ◽  
Guo Cheng Ren
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Optimal Design ◽  
High Speed ◽  
Dynamic Performance ◽  
Design Stage ◽  
Beam Structure ◽  
Element Analysis ◽  
Blanking Process ◽  
Dynamic Performance Analysis

This paper reviews the background and significance to investigate the high-speed speed blanking process modeling simulation and optimization of large blanking machine equipment for CNC uncoiling, leveling and shearing line. And a powerful tool has been providing to of heavy machinery optimal design specifications. The finite element model of beam structure has been established by using a three-dimensional modeling software UG NX4.0 CAD and finite element analysis software ANSYS. Then the static and dynamic characteristics results of the whole beam structure have been simulated. On the basis of analysis results, the optimal static and dynamic performance of square cross-section of the beam structure has been obtained. Drawings at the design stage of large blanking machine equipment for NC uncoiling, leveling and shearing line, the use of finite element theory and modal analysis theory, the structure of the blanking machine static and dynamic performance analysis and prediction using optimal design method for optimization, the new machine to improve job performance, improve processing accuracy, shorten the development cycle and enhance the competitiveness of products is very important.

Structure Analysis and Optimization for High-Speed Vertical Machining Tool Table

2011 ◽  
Vol 120 ◽  
pp. 197-202
Author(s):  
Fei Zhang ◽  
Dong Qiang Gao ◽  
Zhi Yun Mao ◽  
Jiang Miao Yi ◽  
Huan Lin
Keyword(s):  
Performance Analysis ◽  
High Speed ◽  
Dynamic Performance ◽  
High Speed Machining ◽  
Static Stiffness ◽  
Performance Requirements ◽  
Overall Performance ◽  
The Cost ◽  
Dynamic Performance Analysis ◽  
Ansys Workbench

In order to meet high-speed machining center’s overall performance requirements, there are four different worktable structures established in SolidWorks, and they are carried out static analysis in ANSYS Workbench to calculate their static stiffness, so that find out the best structure. In meeting the worktable stiffness, the best structure is optimized in ANSYS Workbench, then the worktable’s quality reduces 8.43% in the original foundation and the cost also decreases, which is a basis for worktable’s dynamic performance analysis.

Sign in / Sign up

Export Citation Format

Share Document