Dynamic Behavior of Composite Adjacent Pre-Stressed Concrete Box Beams Bridges
Author: Hajir A. Ali
Publisher:
Published: 2022
Total Pages: 0
ISBN-13:
DOWNLOAD EBOOKComposite 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).