Bridges’ Dynamics
Bridges’ Dynamics

Author: George T. Michaltsos Ioannis G. Raftoyiannis

Publisher: Bentham Science Publishers

Published: 2012-07-09

Total Pages: 288

ISBN-13: 1608052206

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Bridges’ Dynamics covers the historical review of research and introductory mathematical concepts related to the structural dynamics of bridges. The e-book explains the theory behind engineering aspects such as 1) dynamic loadings, 2) mathematical concepts (calculus elements of variations, the d’ Alembert principle, Lagrange’s equation, the Hamilton principle, the equations of Heilig, and the δ and H functions), 3) moving loads, 4) bridge support mechanics (one, two and three span beams), 5) Static systems under dynamic loading 6) aero-elasticity, 7) space problems (2D and 3D) and 8) absorb systems (equations governing the behavior of the bridge-absorber system). The e-book is a useful introductory textbook for civil engineers interested in the theory of bridge structures.

Topics in Dynamics of Bridges, Volume 3
Topics in Dynamics of Bridges, Volume 3

Author: Alvaro Cunha

Publisher: Springer Science & Business Media

Published: 2014-07-08

Total Pages: 146

ISBN-13: 1461465192

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Topics in Dynamics of Bridges, Volume 3: Proceedings of the 31st IMAC, A Conference and Exposition on Structural Dynamics, 2013, the third volume of seven from the Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Structural Dynamics, including papers on: Vibration Monitoring Damping Damage Detection Health Monitoring Dynamic Behavior Dynamic Modeling Human-Induced Vibration

Dynamic Behavior of Composite Adjacent Pre-Stressed Concrete Box Beams Bridges
Dynamic Behavior of Composite Adjacent Pre-Stressed Concrete Box Beams Bridges

Author: Hajir A. Ali

Publisher:

Published: 2022

Total Pages: 0

ISBN-13:

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Composite adjacent box beams have been utilized to construct bridges as accelerated bridge constructions. These bridges are constantly subjected to the effect of a moving load as vehicles passing over them. Dynamic load allowance (DLA) is a reliable approach to show the amount of that vehicle-bridge interaction. The allowable value of the load allowance factor is 1.33 in AASHTO LRFD (2017), the Bridge Design Specifications. Many researchers have shown that the dynamic load allowance (DLA) value of AASHTO LRFD (2017) does not necessarily yield to a satisfactory account for the dynamic response of highway bridges under moving load. In addition, there is no comprehensive data about adjacent box beams bridges regarding the dynamic load allowance (DLA). Therefore, there is a need to perform a detailed dynamic analysis of vehicle-induced vibration to accurately estimate the dynamic load allowance (DLA) values. This dynamic analysis should include the influence of the most important dynamic parameters, which are related to both the vehicle and bridge circumstances. A field assessment platform was implemented; two adjacent concrete box beams bridges that were dynamically evaluated under the effect of the vehicle-bridge interaction. Then, based on the collected field data, the dynamic load allowance (DLA) values were calculated for all installed instruments under the effect of numerous load cases. The influence of vehicle weights, speeds, brakes, and road roughness conditions on the values of the load allowance factor (DLA) was conducted. In addition, a full scale finite element analysis was performed to complement the field investigation by looking at other dynamic parameters. Finite element method was utilized to model the adjacent box beams bridge of Fairmount Rd according to the asconstructed drawing and ODOT bridge design manual. After modeling, the bridge model was calibrated and validated to analytically investigate the effect of other dynamic parameters on the behavior of this bridge when it is subjected to a moving vehicle. Moving load included two kinds of analysis, the model analysis, and the dynamic analysis. Hence, a parametric study was performed to investigate the effect of an adjacent concrete box beams bridge span length, skew angle, depth, width, and the effect of the material properties of its girders on the values of the dynamic load allowance (DLA). Results of this study illustrate that the dynamic effect of adjacent box beams bridges subjected to moving truck is too important. Under the effect of vehicle-induced vibration, the dynamic load allowance (DLA) values undergoing the effect of most of the investigated parameters were higher than the design limit of AASHTO LRFD (2017). The dynamic load allowance (DLA) value is considerably affected by the speed of the vehicle, road roughness condition and truck braking, skew angle, and stiffness. An empty truck can increase the values of the allowance factor (DLA). Furthermore, the longer the span length of a bridge, the lower recoded dynamic load allowance (DLA) values were. Depth and width of an adjacent box beams bridge and deck thickness have no effect on the values of the dynamic load allowance (DLA).

Bridge Loads
Bridge Loads

Author: Colin O'Connor

Publisher: CRC Press

Published: 2000-08-03

Total Pages: 368

ISBN-13: 1135805091

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This book provides a detailed summary of bridge loads from an international perspective. The authors cover all aspects from the methodology behind the calculation of bridge loads and the complex interactions between loads and bridges, to economic considerations. A wide range of bridge loads are covered, including highway vehicle loads, pedestrian l

Effect of Design Parameters on the Dynamic Response of Bridges
Effect of Design Parameters on the Dynamic Response of Bridges

Author:

Publisher:

Published: 2000

Total Pages: 39

ISBN-13:

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Engineers and researchers have long recognized the importance of vehicle-induced vibration with regard to the response and service life of bridges. In spite of the recognition of the importance and role of dynamic response in deterioration and fatigue damage, the use of current design practices can still result in bridges with undesirable dynamic response characteristics. The primary objective of this study was to develop a procedure for representing moving loads on a bridge model within the context of a commercially available computer code. Such an evaluation might reveal ways to improve design procedures to mitigate unacceptable dynamic response. To achieve this goal, it was necessary to employ a moving load, and, thus, a secondary objective was to develop a procedure for representing moving loads on a bridge model within the context of a commercially available computer code. A third objective was to evaluate the relative effects of various parameters that have a substantial effect on dynamic response. Finite element models of typical bridge structures were developed using ANSYS, a commercially available computer code. A feature of this program, the ANSYS Parametric Design Language (APDL), was employed to represent moving loads with various characteristics. The algorithm developed to represent transient loads in the finite element beam model solution provided results essentially identical with those determined from theory. The relative influence of various design and load parameters was investigated using a finite element model of a section of an actual bridge. Midspan displacements of the bridge were calculated and normalized with respect to the static displacement. Changes in displacement attributable to modifications of the bridge characteristics and to loading parameters were determined.