Dynamic Analysis of Non-Uniform Continuous Girder Bridge under Moving Vehicle

2011 ◽  
Vol 243-249 ◽  
pp. 1634-1637
Author(s):  
Zhi Gang Chen ◽  
Zi Lin Peng

For non-uniform continuous bridge in actual projects, the theoretical analysis and field testing of the dynamic response under moving vehicle are carried out. Firstly, Euler-Lagrange equation is applied to derive the vibration equation of three-axle vehicle. Then one obtains the dynamic analysis model by using the finite element method and the vehicle-bridge interaction equation based on the displacement coordination relationship of the contact between wheels and bridge. Lastly, numerical solutions are presented according to the dynamic response of the bridge, compared with the real values. The results show that: the roadway roughness and vehicle speed strongly influence the impact factor.

2013 ◽  
Vol 671-674 ◽  
pp. 1399-1402
Author(s):  
Ying Sun ◽  
Jian Gang Sun ◽  
Li Fu Cui

To study the impact of floating roof on seismic response of vertical storage tank structure system subjected to seismic excitation, select 150000m3 storage tanks as research object, and the finite element analysis model of storage tanks with and without floating roof were established respectively. The seismic response of these two types of structure in different site conditions and seismic intensity were calculated and the numerical solutions were compared. The results show that floating roof has little impact on base shear and base moment in different site conditions and seismic intensity. Floating roof can effectively reduce the sloshing wave height. The influence of floating roof on dynamic fluid pressure decreases with the increase of seismic intensity, which is less affected by ground conditions.


2014 ◽  
Vol 580-583 ◽  
pp. 1212-1217
Author(s):  
Qi Song ◽  
Jia Qi Guo ◽  
Wen Hua Chen ◽  
Ping Guo

Zhengyangmen gate tower is a national emphasis cultural relic unit along the north-south axis of Beijing, which is above the Beijing metro line 2. Based on dynamic analysis model of gate tower and the position of gate tower and subway, the dynamic response characteristics of gate tower induced by Beijing metro line 2 are calculated, and compared with the in-site vibration test data.


Author(s):  
Ali Asghar Jafari ◽  
Nader Vahdat Azad

In this paper, the effects of various parameters influencing on the dynamic response of composite bridge are investigated by FEM method. Herein composite bridge with one, two and four degree of freedom for vehicle has been studied. The corresponding Equations of motion are integrated numerically by applying the Newmark’s method. The models were verified by analytical and numerical solutions available for isotropic bridge. The speed of the vehicle, mass ratio, bridge damping on the dynamic deflection and acceleration and effect of composite bridge layup have been analyzed. Bridge damping can significantly decrease the acceleration of the structure, and it is true particularly for higher values of the speed parameters. Dynamic deflection is not influenced by damping changes; however, it also reduces with the increase of the damping ratio. Bridge damping has negligible effect on the vehicle acceleration. The bridge acceleration generally increases with the mass parameter. The vehicle acceleration increases much steeply and reaches much higher values for large mass parameters.


2012 ◽  
Vol 170-173 ◽  
pp. 1361-1366 ◽  
Author(s):  
Zhao Bo Meng ◽  
Teng Fei Zhao ◽  
Shi Cai Cui ◽  
Jie Jin

Taking Xi’an Bell Tower and metro line 2 as research background, at first, according to the theory of Euler-Bernoulli beam in Winkler foundation, the analysis model of train-track-foundation system was established, and then, time-history curve of metro-induced loading acts on tunnel structure is obtained by using Matlab produce platform. Secondly, two-dimensional finite element model of the structure-soil-tunnel interaction model was established using ANSYS. Taken loading time delay into consideration for the first time, dynamic response law of the bell tower under the metro-vibration loading is obtained. Finally, the impact of metro line 2 on Xi’an Bell Tower was evaluated according to the Technical specification for protection of historic buildings against man-made vibration.


2021 ◽  
Vol 15 (2) ◽  
Author(s):  
Petr Jančík ◽  
Tomáš Hyhlík

This article presents the kinematic and dynamic analysis of a dam break flow based on data obtained from numerical solutions by the smoothed particle hydrodynamics (SPH) method. The method and original algorithms necessary for correct pressure evaluation are thoroughly described. The pressure evaluation method consists of data reading using virtual sensors and filtration in the time domain using the weight function. A simple convergence study showing the independency of the evaluated parameters of spatial resolution is presented together with validation of the introduced methods and algorithms using a simple hydrostatic problem and experimental data available in the literature. We focus on two parameters that describe the problem: distance of the downstream vertical wall from the edge of the liquid column and the column’s height to width ratio. We found that the impact can be divided into three consecutive phases characterized by specific kinematic (flow patterns) and dynamic (exerted pressure and forces) behavior and different roles of the investigated parameters during these phases. During the early stages of an impact, the column’s distance from the vertical wall plays a major role. A dependency between the column distance and the force peak in this stage was identified in the form of a power function. In the second stage, when a rolling wave emerges, the vertical wall position influences the shape of the wave and the pressure distribution on the wall. The total force is greater in this phase for lower column height to width ratios due to the higher total momentum of the liquid. In the third stage, when the rolling wave impacts the liquid surface, the employed methodology with two-dimensional solution and free-surface approach seems to reach its limits of applicability. A more complex modelling would be necessary to capture this phase of the impact properly.


1971 ◽  
Vol 93 (1) ◽  
pp. 310-316 ◽  
Author(s):  
S. Dubowsky ◽  
F. Freudenstein

The theory developed in Part I has been applied to the determination of the dynamic response of the Impact Pair under various operating conditions. Simulation techniques, as well as approximate methods used in control theory, have been used for this purpose.


2011 ◽  
Vol 108 ◽  
pp. 105-110 ◽  
Author(s):  
Hong Bing Gao ◽  
Zhao Jian Yang

Take one large miner high electric draught shearer for example. According to the lumped mass method, the gear’s moment of inertia of the shearer’s cutting part was equivalent to the gears connecting the output shaft of the electric cutting motor, the stiffness of central shaft and coupling was equivalent to the output elastic shaft of the electric cutting motor, and the dynamic analysis model of the elastic shaft of the cutting part was set up. Based on this model, the lagrange equation was built. The critical speed of the elastic shaft system, the motion situation on main vibration and harmonic vibration mode, motor shaft’s angular displacement, angular velocity, and angular acceleration’s dynamic response process under the condition of step loads were all analyzed and obtained. The critical speed provided theoretical basis for choosing the working speed of every shaft system of the shearer. The hollow elastic shaft had a protective effect to cutting motor’s damping and overload. The research results provided theoretical basis for the design of the elastic shaft of large miner high shearer.


2021 ◽  
Vol 21 (3) ◽  
pp. 353-360
Author(s):  
Duong Nguyen Thi Bach ◽  
Dan Nguyen Anh

Now, the field experiments according to the non-destructive test method are developing widely in diagnostics and verification of structural engineering. To research and apply the impact vibration test, one of these non-destructive methods, the construction of the design dynamic analysis model is significant. The paper goes into research on the formulas to determine the dynamic spring coefficients according to Japanese and Vietnamese standards. Then, apply calculations for dynamic analysis models of pile foundations built in the Binh Thuan sea area. The impact vibration test in the field shows the appropriate formula for calculating the coefficient of dynamic springs in Binh Thuan, Vietnam.


2010 ◽  
Vol 32 (4) ◽  
pp. 222-234 ◽  
Author(s):  
Nguyen Viet Khoa ◽  
Tran Thanh Hai

In this paper an idea for crack detection of a multi-cracked beam-like structure by analyzing the vibration measured directly from the vehicle is presented. The crack model is adopted from fracture mechanics. The dynamic response of the bridge-vehicle system is measured directly from the moving vehicle. When the vehicle moves along the structure, the dynamic response of the vehicle is distorted by the cracks at their locations. These distortions are generally small and difficult to be detected visually. In order to detect the cracks, Wavelet Transform - an effective method of detecting such small distortions was adopted. The existence of the cracks can be revealed by large values (peaks) in the wavelet transform. Locations of the cracks can be determined by positions of the peaks and the vehicle speed. Numerical results show that the method can detect cracks as small as 10 % of the beam height with noise level up to 5%. The proposed method is applicable for low velocity-movements while high velocity-movements are not recommended.


2013 ◽  
Vol 353-356 ◽  
pp. 1718-1723
Author(s):  
Teng Fei Zhao ◽  
Zhao Bo Meng ◽  
Jie Jin ◽  
Xi Feng Li

Taking Xian Bell Tower and metro line 6 as research background, at first, according to the theory of Euler-Bernoulli beam in Winkler foundation, the analysis model of train-track-foundation system was established, and then, time-history curve of metro-induced loading acts on tunnel structure is obtained by using Matlab software. Two-dimensional finite element model of the structure-soil-tunnel interaction model was established using software Ansys,. Taken loading time delay into consideration for the first time, dynamic response law of the bell tower under the metro-vibration loading is obtained. Finally, the impact of metro line 6 on Xian Bell Tower was evaluated according to the Technical specification for protection of historic buildings against man-made vibration. Xi'an Bell Tower timber structure is safe when two trains running of the line 6.


Sign in / Sign up

Export Citation Format

Share Document