Experimental and numerical investigation of the wind effects on long span bridge decks

Iman, Ashtiani Abdi
Long span bridges are susceptible to wind. Hence it is important to study their wind-induced vibrations to avoid any probable structural failures. In this thesis, the results of an experimental and computational investigation of the aerodynamic characteristics of trapezoid bridge deck cross-sections with three different aspect ratios (10, 12 and 15) and four different side angles (75º, 60 º, 45 º and 30 º) are analyzed and presented. The flow around rigid fixed bridge deck models is investigated to obtain the relevant aerodynamic coefficients and the vortex shedding frequency and Strouhal number. Two dimensional unsteady Reynolds Averaged Navier-Stokes equations are solved using commercial CFD software at different Reynolds numbers. The numerical results are compared with the experimental data obtained by testing the model bridge decks geometries in a low speed wind tunnel. The results of this study demonstrate that the models aerodynamic parameters except their lift coefficient are almost dependent on the aspect ratio. In addition, the influence of side angle on all aerodynamic parameters has to be taken in account.


Improvement of computational software for composite curved bridge analysis
Kalaycı, Ahmet Serhat; Topkaya, Cem; Department of Civil Engineering (2005)
In highway bridge construction, composite curved girder bridges are becoming more popular recently. Reduced construction time, long span coverage, economics and aesthetics make them more popular than the other structural systems. Although there exist some methods for the analysis of such systems, each have shortcomings. The use of Finite Element Method (FEM) among these methods is limited except in the academic environments. The use of commercial FEM software packages in the analysis of such systems is cumb...
Effects of vertical excitation on seismic performance of highway bridges and hold-down device requirements
Domaniç, Kemal Arman; Caner, Alp; Department of Civil Engineering (2008)
Most bridge specifications ignore the contribution of vertical motion in earthquake analyses. However, vertical excitation can develop significant damage, especially at bearing locations as indeed was the case in the recent 1999 İzmit Earthquake. These observations, combined with recent developments in the same direction, supplied the motivation to investigate the effects of vertical component of strong ground motion on standard highway bridges in this study. Reliability checks of hold-down device requireme...
Evaluation of scouring reliability at bridge abutments
Yanmaz, Ali Melih (2012-04-26)
Serious scouring may take place around bridge abutments during floods, which can lead to considerable damage or structural collapse. Design of abutment footings must, therefore, rely on the estimation of maximum possible depth of scour through the bridge opening. Deterministic scour-prediction equations are based on simplified assumptions and they do not account for randomness of the scouring variables, which leads to an unavoidable risk in footing design. This study is concerned with the development of a n...
Caner, Alp; Shaban, Nefize (null; 2017-01-05)
A standard highway bridge has usually multi simple spans supported over piers by elastomeric bearings in Turkey. The bearings usually do not provide a positive connection but in contact with girder and pier by only gravitational forces. In this study, a model test bridge of about ½ scale have been shaken under low to moderate earth quakes to determine the change in response of the bridge with different seismic isolation configurations. Three configurations of bearings are elastomeric bearings, lead core bea...
Scour and scour protection at bridge abutments
Kayatürk, Şerife Yurdagül; Göğüş, Mustafa; Department of Civil Engineering (2005)
Bridge failures are mainly caused by scouring the bed material around bridge foundations during flood. In this study, scour phenomenon around bridge abutments is experimentally studied. Effect of abutment size, location and size of the collars placed around the abutments, time evaluation of scour hole around the abutment, scour characteristics of abutment and pier interaction were experimentally investigated. Scour measurements were conducted in a rectangular channel of 30 m long and 1.5 m wide filled with ...
Citation Formats
A. A. Iman, “Experimental and numerical investigation of the wind effects on long span bridge decks,” M.S. - Master of Science, Middle East Technical University, 2011.