GLORIA

GEOMAR Library Ocean Research Information Access

X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • World Scientific Pub Co Pte Ltd  (12)
Material
Publisher
  • World Scientific Pub Co Pte Ltd  (12)
Person/Organisation
Language
Years
  • 1
    Online Resource
    Online Resource
    Flutter Stability of a Long-Span Suspension Bridge During Erection in Mountainous Areas
    World Scientific Pub Co Pte Ltd ; 2020
    In:  International Journal of Structural Stability and Dynamics Vol. 20, No. 09 ( 2020-08), p. 2050102-
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd, Vol. 20, No. 09 ( 2020-08), p. 2050102-
    Abstract: In mountainous areas, more challenges are expected for the construction of long-span bridges. The flutter instability during erection is an outstanding issue due to flexible structural characteristics and strong winds with large angles of attack. Taking the suspension bridge as an example, the flutter stability of the bridge with different suspending sequences was investigated. First, the dynamic characteristics of the bridge during erection were computed by the finite element software ANSYS, along with the effects on flutter stability discussed. Then, different aerodynamic shapes of the bridge girder during erection were considered. The aerodynamic coefficients and the critical flutter state were determined by wind tunnel tests. Based on the above analysis, some structural measures are proposed for improving the flutter stability of the bridge during erection. The results show that the flutter stability of the bridge during erection is related to the suspending sequence and the aerodynamic shape of the girder. Owing to the structural dynamic characteristics, the bridge has better flutter stability when the girder segments are suspended symmetrically from the two towers to the mid-span. Considering the construction requirement that the bridge deck should be laid without intervals, this structural superiority is seriously weakened by the unfavorable aerodynamic shape of the girder. In order to improve the flutter stability of the bridge during erection, an effective way is to adopt some temporary structural strengthening measures.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455420501023
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2020
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 2
    Online Resource
    Online Resource
    Dynamic Amplification Factors of an Arch Bridge Under Random Traffic Flows
    World Scientific Pub Co Pte Ltd ; 2023
    In:  International Journal of Structural Stability and Dynamics
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd
    Abstract: Among large-span bridges, arch bridges have relatively high stiffness, which may lead to large dynamic amplification factors (DAFs). The DAFs suggested by current codes mostly originate from common simply supported beam bridges. Previous DAF studies on dynamic vehicle–bridge solutions for arch bridges have mainly focused on one or two side-by-side vehicles. However, complex traffic flows with randomness rather than one or two vehicles act on bridges. DAFs that consider the effects of random traffic flows have not previously been reported. In this study, a random traffic–bridge vibration solution was established to explore the DAFs of arch bridge components. The randomness of the traffic parameters and road roughness was explored. The randomness of the external excitation, including traffic flow and road roughness, resulted in random dynamic responses and DAFs of the arch bridge components. Normal distributions could be used to fit the DAF distributions of each arch bridge component under random vehicle spacing, weight, speed, and road roughness. Under random traffic parameters, the coefficients of variation of the DAFs exceeded the 5% accepted level. The shortest suspenders were more sensitive to the randomness of the traffic flow parameters. Both the mean and coefficient of variation of the DAFs increased with worsening of the road conditions. The influence of the randomness of the road roughness on the DAFs of arch bridges must be considered, particularly for the shortest suspender. The 95% upper confidence limits of the DAFs for all components may be greater than the suggested values in the code.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455424500640
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2023
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 3
    Online Resource
    Online Resource
    Dynamic Analysis of a Coupled System of High-Speed Maglev Train and a Flexible Long-Span Continuous Rigid Frame Bridge
    World Scientific Pub Co Pte Ltd ; 2023
    In:  International Journal of Structural Stability and Dynamics Vol. 23, No. 15 ( 2023-09-30)
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd, Vol. 23, No. 15 ( 2023-09-30)
    Abstract: The dynamic characteristics, deformation and installation accuracy of the bridge structure will have a greater impact on the response of maglev system. This study performs the dynamic analysis of a flexible long-span continuous rigid frame bridge induced by high-speed maglev train. To achieve this, the spatial coupling analysis model is first established. Then, the influence of track irregularities and speed on the maglev system is analyzed. In addition, the mechanism of vertical resonance of the bridge and vehicle under the action of harmonic loads at low speed is also studied by a semi-analytical approach. The results show that the influence of the long-span bridge deformation on car-body vertical acceleration is greater than that of track irregularity. The resonance exists between train and the long-span bridge at low speed. When the frequency of the harmonic loads is consistent with the basic frequency of the bridge, it will cause the bridge resonance. The resonant speed range of the rigid car-body is 20–40[Formula: see text]km/h. During bridge design, it shall be avoided that the basic frequency of the bridge is consistent with that of the vehicle.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455423501742
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2023
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 4
    Online Resource
    Online Resource
    Random Characteristics of Vehicle-Bridge System Vibration by an Optimized Pseudo Excitation Method
    World Scientific Pub Co Pte Ltd ; 2020
    In:  International Journal of Structural Stability and Dynamics Vol. 20, No. 05 ( 2020-05), p. 2050069-
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd, Vol. 20, No. 05 ( 2020-05), p. 2050069-
    Abstract: The pseudo excitation method (PEM) is improved for its efficiency by incorporating the self-adaptive Gauss integration (SGI) technology as a new combining integration. The PEM can transform the random rail irregularities into some pseudo harmonic excitation, which is a mature approach to deal with the random excitation for vehicle–bridge systems. The SGI was used to distinguish the significant from the insignificant parts of an integral section for the random excitation frequency on the stochastic response of the system, thereby reducing the computational effort required for the random vibration analysis of the system. Also, the SGI can intelligently handle the recognized integral section, by subdividing the important sections into several necessary frequency points, making rough decomposition, and allowing the unimportant regions to be eliminated. Based on selected frequency points, the deterministic pseudo harmonic excitations were generated, and then the standard deviation (SD) of the time history for the system was calculated by the PEM. The vehicle subsystem was simulated as a 23-degree of freedom model, and the bridge subsystem as a three-dimensional finite element model. The time-varying power spectral density (PSD) plots of the system were presented. Besides, the cumulative distribution function (CDF) of the response was calculated using Poisson’s crossing assumption. The random characteristics for the vehicle–bridge vibrations for different speeds and rail irregularities were calculated.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455420500698
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2020
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 5
    Online Resource
    Online Resource
    Vortex-Induced Vibration of a Tall Bridge Tower with Four Columns and the Wake Effects on the Nearby Suspenders
    World Scientific Pub Co Pte Ltd ; 2020
    In:  International Journal of Structural Stability and Dynamics Vol. 20, No. 09 ( 2020-08), p. 2050105-
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd, Vol. 20, No. 09 ( 2020-08), p. 2050105-
    Abstract: With the increasing span of suspension bridges, the towers have higher heights and have become more flexible, and so do the nearby suspenders. Not only are the towers easy to be affected by winds, but also the nearby suspenders by the wake flow of the towers. To enhance the structural stiffness, a bridge tower may be designed with more columns, but this design may lead to strong aerodynamic interference among the columns, complicating the wind-induced behaviors of the tower and nearby suspenders. In this paper, wind tunnel tests and numerical simulations were carried out to investigate the vortex-induced vibration of a tall bridge tower with four columns, and the wake effects on nearby suspenders. The results show that the displacement response at the tower top increases with the increasing wind speed. No obvious lock-in region is observed, as different cross-sections of the tower show different vortex shedding characteristics. The vortex shedding characteristics are determined mainly by the aerodynamic forces acting on the leeward columns. In the wake of the tower, the aerodynamic forces of the suspenders have the same dominant frequencies as the shedding frequencies of the vortices from the tower. The frequencies may approach the natural frequencies of the suspenders, causing possible wake-induced vibration that should be avoided for a good design.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455420501059
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2020
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 6
    Online Resource
    Online Resource
    An Efficient Dimension-Adaptive Numerical Integration Method for Stochastic Dynamic Analysis of Structures with Uncertain Parameters
    World Scientific Pub Co Pte Ltd ; 2021
    In:  International Journal of Structural Stability and Dynamics Vol. 21, No. 03 ( 2021-03), p. 2150035-
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd, Vol. 21, No. 03 ( 2021-03), p. 2150035-
    Abstract: This paper presents a novel dimension-adaptive numerical integration method for dynamic analysis of structures with stochastic parameters subjected to deterministic excitations. First, an efficient dimension-adaptive algorithm is proposed to detect the importance of each random parameter involved in the structural model, based on which the quadrature nodes used for numerical integration can be collocated more reasonably. Then, the Gaussian quadrature formulas are used to evaluate the structural response statistics. To further improve the robustness and efficiency of the proposed method, the dimension-adaptive integration is only used to calculate the structural displacement response statistics. The velocity and acceleration response statistics are further evaluated using the finite difference formulas based on the concept of stochastic difference. Such a strategy is especially attractive when evaluating the response statistics of the derivative processes requires more quadrature nodes than that of the original process. Finally, two numerical examples encountered in civil engineering, including a shear frame with stochastic parameters subjected to a seismic ground motion and an Euler beam with unidimensional stochastic field of material properties (discretized via the Karhunen–Loève expansion) subjected to a moving load are studied to illustrate the performance of the proposed method. Via the numerical results, the accuracy and efficiency of the proposed method are verified.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455421500358
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2021
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 7
    Online Resource
    Online Resource
    Dynamic Response Analysis of Train–Vehicle–Bridge System Under Train-Induced Winds
    World Scientific Pub Co Pte Ltd ; 2023
    In:  International Journal of Structural Stability and Dynamics Vol. 23, No. 12 ( 2023-07-30)
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd, Vol. 23, No. 12 ( 2023-07-30)
    Abstract: For rail-cum-road bridges with single-level arrangement, there are not only dynamic interference, but also aerodynamic interference between trains and vehicles, which means that the train-induced winds generated by high-speed trains are non-negligible for vehicles. In this work, the test method of moving vehicle model is used to test the aerodynamic characteristics of vehicles under train-induced winds. Then, the model of coupled vibration of train–vehicle–bridge system considering train-induced winds is established. Finally, taking a rail-cum-road bridge with single-level arrangement as an example, the coupled vibration of train–vehicle–bridge system considering train-induced winds is analyzed, and the influence of train-induced winds, lateral spacing between trains and vehicles on train–vehicle–bridge system is discussed. The results show that train-induced winds decrease with the increase of the lateral spacing between trains and vehicles. Without considering train-induced winds, the moving train has a greater impact on the vertical response of the vehicle, and a smaller impact on the lateral response of the vehicle. When considering train-induced winds, the lateral response of the vehicle increases significantly, but decreases with the increase of the lateral spacing. In addition, road conditions and the setting of anti-dazzle plates can change traffic safety under train-induced winds.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455423501328
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2023
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 8
    Online Resource
    Online Resource
    Intelligent Surface Cracks Detection in Bridges Using Deep Neural Network
    World Scientific Pub Co Pte Ltd ; 2023
    In:  International Journal of Structural Stability and Dynamics
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd
    Abstract: Cracking is one of the most common bridge diseases. If bridge cracks are not repaired: in time, they may cause gradual changes to the concrete structure, which can seriously affect its strength. A network called YOLOv5-TS is what we suggest to detect intelligently bridge surface cracks in images. To improve the network performance, we integrate SPPCSPC into the original YOLOv5 network to ensure adaptive image output and obtain receptive fields of various sizes. Meanwhile, transposed convolution is incorporated to improve the capacity of the network for learning weights on its own and reduce characteristic information loss. In response to the diverse morphology of bridge cracks, cracks are identified according to their mechanical causes crack inclination, and divided into four categories: horizontal cracks (0[Formula: see text]–20[Formula: see text] ), low-angle cracks (20[Formula: see text]–45[Formula: see text] ), vertical cracks (70[Formula: see text]–90[Formula: see text] ) and high-angle cracks (45[Formula: see text]–70[Formula: see text] ). Experiments on the ZJU SYG crack data set confirm that the proposed YOLOv5-TS has a better crack intelligent identification effect on bridge surface images than other compared baselines. The best performance of YOLOv5-TS is found in mAP@0.5 (0.752), mAP@0.5:0.95 (0.518), and recall (0.794), thus demonstrating the model’s practical value.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455424500469
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2023
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 9
    Online Resource
    Online Resource
    Dynamic Interaction Analysis of High-Speed Maglev Train and Guideway with a Control Loop Failure
    World Scientific Pub Co Pte Ltd ; 2022
    In:  International Journal of Structural Stability and Dynamics Vol. 22, No. 10 ( 2022-08)
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd, Vol. 22, No. 10 ( 2022-08)
    Abstract: The fault of a control loop can occur when a high-speed maglev train is running on guideways, which will affect the dynamic responses of the maglev train and guideway and is one of the controlling cases in the design of guideway functional parts. To study the dynamic response of the vehicle and guideway when a control loop failure occurs, first, a spatial coupling vibration model, which includes the three-dimensional (3D) maglev trains, guideways, piers and electromagnetic force based on the proportional-derivative (PD) controller, is proposed, and the electromagnetic force model for a control loop failure is presented. Second, the effectiveness of the coupling vibration model is verified based on the measured results of the Shanghai maglev line (SML). Finally, the dynamic responses of maglev train and guideway are discussed under a suspension magnet or guidance magnet with a control loop failure, and the influences of the location of the fault, the weight of the vehicle and the preload of the guidance system are analyzed. The most disadvantageous load value acting on the functional parts in case of magnet failure is obtained. The results show that the dynamic responses of the maglev train with a control loop failure will vary due to the location of the fault on trains and guideways, the weight of vehicle and the lateral preload. Although a control loop failure has little influence on the dynamic response of the guideway, the suspension force or guidance force on guideway will increase suddenly, and this sudden force is far larger than the vehicle static load or lateral preload of guidance magnets.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455422410127
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2022
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
  • 10
    Online Resource
    Online Resource
    Random Dynamic Analysis of Wind-Vehicle-Bridge System Based on ARMAX Surrogate Model and High-Order Differencing
    World Scientific Pub Co Pte Ltd ; 2023
    In:  International Journal of Structural Stability and Dynamics Vol. 23, No. 02 ( 2023-01-30)
    Details
    In: International Journal of Structural Stability and Dynamics, World Scientific Pub Co Pte Ltd, Vol. 23, No. 02 ( 2023-01-30)
    Abstract: To investigate the stochastic characteristics of vehicle-bridge (VB) system under crosswind, an efficient method which combines AutoRegressive Moving Average with eXogenous inputs (ARMAX) model, high-order differencing (HOD) and important sample was proposed in this paper. First, the wind turbulence spectra relative to a moving vehicle and equivalent static gust load method were adopted to simplify the turbulent wind field of VB system, and a wind-vehicle-bridge (WVB) model was established and verified. Then, an analysis framework for WVB system based on ARMAX model was proposed, and HOD method and important sample were used to improve the prediction performance of the surrogate model. Prediction accuracy and calculation efficiency of proposed AMRAX model were verified and compared by Monte Carlo simulation (MCS). Finally, the impacts of vehicle speed and wind velocity on the stochastic characteristics of train response were discussed. Results indicate that the HOD method has significantly improved the prediction performance of ARMAX model for lateral response of trains, and the train responses predicted by ARMAX model based on HOD and important sample show perfect agreement with target results. Compared with MCS, the calculation efficiencies of proposed ARMAX model are improved by about two orders of magnitude. The extreme values of the train response with different vehicle speed and wind velocity gradually obey right skewness distribution, especially the lateral acceleration.
    Type of Medium: Online Resource
    ISSN: 0219-4554 , 1793-6764
    URL: Article
    DOI: 10.1142/S0219455423500219
    Language: English
    Publisher: World Scientific Pub Co Pte Ltd
    Publication Date: 2023
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
    Online Resource
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...