Published online on May 2020
Amir Fatollahzadeh, Morteza Naghipour, Mehdi Hamidi
Abstract:Cable-stayed bridges play a key role in the sustainable development of regions. In recent years, various kinds of these bridges, in terms of cable arrangement, have been built. Due to harsh conditions of their surroundings, several hazards always threat cable-stayed bridges one of which is the progressive collapse phenomenon which may give rise to disastrous events like disproportionate deformations or entire collapse and huge damages. This paper, consequently, aims to determine the effect of geometrical characteristics of this type of bridge on progressive collapse and introduce the best arrangement to deal with it. For an investigation of this phenomenon, assessment is carried out by non-linear time history analysis using SAP2000v17. The axial force of adjacent cables, therefore, will be evaluated within 0.1 second-step under specific load combination proposed by PTI recommendation in order to compare it with the ultimate limit. It can be concluded that the dimension of the deck and height of pylons do not have any significant impact on the behavior of the structure against progressive collapse. In addition, the evaluation of different arrangements of cables made it clear that Semi Harp and Fan arrangements can resist better against the subsequent failure of other cables compared with the Harp arrangement.
International Journal of Bridge Engineering, Vol. 8, No. 1, 2020: pp. 1-14
Osama Mohammed Elmardi Suleiman, Mahmoud Yassin Osman, Tagelsir Hassan
Abstract:Finite element (FE) method is presented for the analysis of thin rectangular laminated composite decks plates under the biaxial action of in – plane compressive loading. The analysis uses the classical laminated plate theory (CLPT) which does not account for shear deformations. In this theory it is assumed that the laminate is in a state of plane stress, the individual lamina is linearly elastic, and there is perfect bonding between layers. The classical laminated plate theory (CLPT), which is an extension of the classical plate theory (CPT) assumes that normal to the mid – surface before deformation remains straight and normal to the mid – surface after deformation. Therefore, this theory is only adequate for buckling analysis of thin laminates. A Fortran program has been developed. New numerical results are generated for in – plane compressive biaxial buckling which serve to quantify the effects of lamination scheme on buckling loading. The results indicate that the symmetric laminate is stiffer than the anti – symmetric one. This phenomenon is caused by coupling between bending and stretching which lowers the buckling loads of symmetric laminate.
International Journal of Bridge Engineering, Vol. 8, No. 1, 2020: pp. 15-34
Abstract:In this study, the effects of the vertical ground motion on the seismic response of the skewed RC bridges were investigated. First, the considered bridge was modeled. Then, the nonlinear time history analysis was used to evaluate the seismic response of the skewed RC bridge at two states with and without applying the effect of the vertical ground motion. The results of studies indicated that the application of the vertical ground motions in the seismic design of bridges was very important. Also, the application or non-application of vertical ground motions had no significant effect on the amount of base shear of the studied RC skew bridge. Moreover, the application of the vertical ground motions caused a significant increase in the bridge response in its vertical direction than non-application.
International Journal of Bridge Engineering, Vol. 8, No. 1, 2020: pp. 35-52
Atteshamuddin S. Sayyad, Yuwaraj M. Ghugal
Abstract:A great deal of literature is available on the flexural analysis of composite beams, plates and shells using higher order shear deformation theories. However, a limited research work is available on the flexural analysis of arches made up of functionally graded (FG) type composite materials using higher order theory. Therefore, flexural analysis of FG arches subjected to uniform load is the main focus of the present study. A trigonometric curved beam theory considering the effects of transverse shear and normal stresses is applied for the flexural analysis of two hinged FG arches. Material properties of FG arches are varied through the thickness according to the power-law distribution. The present theory imparts the sinusoidal variation of normal strain and cosine distribution of shear strain through the thickness. It satisfies the zero shear stress conditions on the top and bottom surfaces of the arch using constitutive relations. Equilibrium equations of the theory are derived within the framework of the principle of virtual work. Analytical solutions for the flexural analysis of two hinge arches are obtained using Navier’s technique. The non-dimensional displacements and stresses are obtained for different radii of curvature and various values of power law coefficients. The results of present theory are compared with those of EBT, FSDT and PSDT theories. The numerical results presented in this study will be useful for the reference of future research in this area.
International Journal of Bridge Engineering, Vol. 8, No. 1, 2020: pp. 53-70
Osama Mohammed Elmardi Suleiman Khayal
Abstract:Failure analysis of laminated composite decks structures has attracted a great deal of interest in recent years due to the increased application of composite materials in a wide range of high-performance structures. Intensive experimental and theoretical studies of failure analysis and prediction are being reviewed. Delamination, the separation of two adjacent plies in composite laminates, represents one of the most critical failure modes in composite laminates. In fact, it is an essential issue in the evaluation of composite laminates for durability and damage tolerance. Thus, broken fibers, delaminated regions, cracks in the matrix material, as well as holes, foreign inclusions and small voids constitute material and structural imperfections that can exist in composite structures. Imperfections have always existed and their effect on the structural response of a system has been very significant in many cases. These imperfections can be classified into two broad categories: initial geometrical imperfections and material or constructional imperfections.
International Journal of Bridge Engineering, Vol. 8, No. 1, 2020: pp. 71-85