Go to the main menu
Skip to content
Go to bottom
REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Interaction and multiscale mechanics
Journal Basic Information
Journal DOI :
Editor in Chief :
J. S. Chen / Y.B. Yang / C. S. David Chen
Volume & Issues
Volume 3, Issue 4 - Dec 2010
Volume 3, Issue 3 - Sep 2010
Volume 3, Issue 2 - Jun 2010
Volume 3, Issue 1 - Mar 2010
Selecting the target year
Effect of road surface roughness on indirect approach for measuring bridge frequencies from a passing vehicle
Chang, K.C. ; Wu, F.B. ; Yang, Y.B. ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 299~308
DOI : 10.12989/imm.2010.3.4.299
The indirect approach for measuring the bridge frequencies from the dynamic responses of a passing vehicle is a highly potential method. In this study, the effect of road surface roughness on such an approach is studied through finite element simulations. A two-dimensional mathematical model with the vehicle simulated as a moving sprung mass and the bridge as a simply-supported beam is adopted. The dynamic responses of the passing vehicle are solved by the finite element method along with the Newmark
method. Through the numerical examples studied, it is shown that the presence of surface roughness may have negative consequence on the extraction of bridge frequencies from the test vehicle. However, such a shortcoming can be overcome either by introducing multiple moving vehicles on the bridge, besides the test vehicle, or by raising the moving speed of the accompanying vehicles.
Nonlinear dynamic response analysis of a long-span suspension bridge under running train and turbulent wind
Wang, S.Q. ; Xia, H. ; Guo, W.W. ; Zhang, N. ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 309~320
DOI : 10.12989/imm.2010.3.4.309
With taking the geometric nonlinearity of bridge structure into account, a framework is presented for predicting the dynamic responses of a long-span suspension bridge subjected to running train and turbulent wind. The nonlinear dynamic equations of the coupled train-bridge-wind system are established, and solved with the Newmark numerical integration and direct interactive method. The corresponding linear and nonlinear processes for solving the system equation are described, and the corresponding computer codes are written. The proposed framework is then applied to a schemed long-span suspension bridge with the main span of 1120 m. The whole histories of the train passing through the bridge under turbulent wind are simulated, and the dynamic responses of the bridge are obtained. The results demonstrate that the geometric nonlinearity does not influence the variation tendency of the bridge displacement histories, but the maximum responses will be changed obviously; the lateral displacement of bridge are more sensitive to the wind than the vertical ones; compared with wind velocity, train speed affects the vertical maximum responses a little more clearly.
Identification of beam crack using the dynamic response of a moving spring-mass unit
An, Ning ; Xia, He ; Zhan, Jiawang ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 321~331
DOI : 10.12989/imm.2010.3.4.321
A new technique is proposed for bridge structural damage detection based on spatial wavelet analysis of the time history obtained from vehicle body moving over the bridge, which is different from traditional detection techniques based on the bridge response. A simply-supported Bernoulli-Euler beam subjected to a moving spring-mass unit is established, with the crack in the beam simulated by modeling the cracked section as a rotational spring connecting two undamaged beam segments, and the equations of motion for the system is derived. By using the transfer matrix method, the natural frequencies and mode shapes of the cracked beam are determined. The responses of the beam and the moving spring-mass unit are obtained by modal decomposition theory. The continuous wavelet transform is calculated on the displacement time histories of the sprung-mass. The case study result shows that the damage location can be accurately determined and the method is effective.
Stochastic space vibration analysis of a train-bridge coupling system
Li, Xiaozhen ; Zhu, Yan ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 333~342
DOI : 10.12989/imm.2010.3.4.333
The Pseudo-Excitation Method (PEM) is applied to study the stochastic space vibration responses of train-bridge coupling system. Each vehicle is modeled as a four-wheel mass-spring-damper system with two layers of suspension system possessing 15 degrees-of- freedom. The bridge is modeled as a spatial beam element, and the track irregularity is assumed to be a uniform random process. The motion equations of the vehicle system are established based on the d`Alembertian principle, and the motion equations of the bridge system are established based on the Hamilton variational principle. Separate iteration is applied in the solution of equations. Comparisons with the Monte Carlo simulations show the effectiveness and satisfactory accuracy of the proposed method. The PSD of the 3-span simply-supported girder bridge responses, vehicle responses and wheel/rail forces are obtained. Based on the
rule for Gaussian stochastic processes, the maximum responses of the coupling system are suggested.
Dynamic response of an elastic bridge loaded by a moving elastic beam with a finite length
Cojocaru, Eugenia C. ; Irschik, Hans ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 343~363
DOI : 10.12989/imm.2010.3.4.343
The present paper is concerned with vibrations of an elastic bridge loaded by a moving elastic beam of a finite length, which is an extension of the authors` previous study where the second beam was modeled as a semi-infinite beam. The second beam, which represents a train, moves with a constant speed along the bridge and is assumed to be connected to the bridge by the limiting case of a rigid interface such that the deflections of the bridge and the train are forced to be equal. The elastic stiffness and the mass of the train are taken into account. The differential equations are developed according to the Bernoulli-Euler theory and formulated in a non-dimensional form. A solution strategy is developed for the flexural vibrations, bending moments and shear forces in the bridge by means of symbolic computation. When the train travels across the bridge, concentrated forces and moments are found to take place at the front and back side of the train.
Vibration simulation of a multi-story high-speed railway station
Gao, Mangmang ; Xiong, Jianzhen ; Xu, Zhaojun ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 365~372
DOI : 10.12989/imm.2010.3.4.365
Station is an important building in high-speed railway, and its vibration and noise may significantly affect the comfort of waiting passengers. A coupling vibration model for train-structure system is established to analyze and evaluate the vibration level of a typical waiting hall under dynamic train load. The motion of a four-axle vehicle with two suspension system is modeled in multi-body dynamics with linear springs and dampers employed. The station is modeled as a whole finite element structure which is 113 m in longitudinal and 163.5 m in lateral, and the stiffness of the station foundation is considered. According to the assumptions that both wheel and rail are rigid bodies and keep contact to each other in vertical direction, and the wheel/rail interaction and displacement coordination in horizontal direction is defined by the simplified Kalker creep theory, the vehicle spatial vibration model has 27 degrees-of-freedom. An overall analysis procedure is made of the train moving through the station, by which the dynamic responses of the train and the station are calculated. According to the comparison between analysis and test results, the actual connection status between different parts of the station is estimated and the vibration level of the waiting hall is evaluated.
Assessment of traffic-induced low frequency sound radiated from a viaduct by field experiment
Kawatani, M. ; Kim, C.W. ; Nishitani, K. ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 373~387
DOI : 10.12989/imm.2010.3.4.373
This study is intended to assess low frequency sound radiated from a viaduct under normal traffic. The bridge comprises steel box girders and wide cantilever decks on which vehicles pass. The low frequency sound and the acceleration response of the bridge under normal traffic are measured to investigate how bridge vibrations affect the low frequency sound observed near the bridge. Observations demonstrate that strong relationships exist between frequency characteristic of bridge`s acceleration response and the sound pressure level of low frequency sound. A noteworthy point is that the dynamic feature of the sound pressure level is mostly affected by dynamic feature of the span locating near the observation point.
Vibration analysis of CFST tied-arch bridge due to moving vehicles
Yang, Jian-Rong ; Li, Jian-Zhong ; Chen, Yong-Hong ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 389~403
DOI : 10.12989/imm.2010.3.4.389
Based on the Model Coupled Method (MCM), a case study has been carried out on a Concrete-Filled Steel Tubular (CFST) tied arch bridge to investigate the vibration problem. The mathematical model assumed a finite element representation of the bridge together with beam, shell, and link elements, and the vehicle simulation employed a three dimensional linear vehicle model with seven independent degrees-of-freedom. A well-known power spectral density of road pavement profiles defined the road surface roughness for Perfect, Good and Poor roads respectively. In virtue of a home-code program, the dynamic interaction between the bridge and vehicle model was simulated, and the dynamic amplification factors were computed for displacement and internal force. The impact effects of the vehicle on different bridge members and the influencing factors were studied. Meanwhile the acceleration responses of some of the components were analyzed in the frequency domain. From the results some valuable conclusions have been drawn.
Performance evaluation of steel and composite bridge safety barriers by vehicle crash simulation
Thai, Huu-Tai ;
Interaction and multiscale mechanics, volume 3, issue 4, 2010, Pages 405~414
DOI : 10.12989/imm.2010.3.4.405
The performance of full-scale steel and composite bridge safety barriers under vehicle crash is evaluated by using the nonlinear explicit finite element code LS-DYNA. Two types of vehicles used in this study are passenger car and truck, and the performance criteria considered include structural strength and deformation, occupant protection, and post-crash vehicle behavior. It can be concluded that the composite safety barrier satisfies all performance criteria of vehicle crash. Although the steel safety barrier satisfies the performance criteria of occupant protection and post-crash vehicle behavior, it fails to satisfy the performance criterion of deformation. In all performance evaluations, the composite safety barrier exhibits a superior performance in comparing with the steel safety barrier.