Published online in September 2017
Ricardo Fabeane, Moacir Kripka, Zacarias M. Chamberlain Pravia
Abstract: The present study aimed to supply parameters that lead to optimized design in composite bridges. To achieve the proposed objectives has been formulated an optimization problem which aims to reduce the cost of bridge cross section by varying the dimensions of the steel girders. The implementation of the proposed formulation has been done by creating a design routine in MS Excel and using the Solver to find the optimized sections to the girders. The specification used in the analysis and design of the girders has been the AASHTO (2012), and the cases studied are of simple span bridges with different spans and a variable number of steel girders in its cross section. The results obtained enabled identification of parameters aimed at the optimized design of composite bridges, showing that the use of criteria based on optimization techniques can lead to a significant reduction in the cost of the structures.
International Journal of Bridge Engineering, Vol. 5, No. 2, 2017: pp. 1-20
Md Ashiquzzaman, Bora Bozkurt, Li Hui, Ahmed Ibrahim, Will Lindquist, Riyadh Hindi
Abstract: In order to construct a wider bridge deck, it is usual to extend the bridge deck past the exterior girders. Construction of these overhangs may result in a number of issues for both steel and concrete girder bridges. Bridge contractors prefer to place the bridge screed and finishing machine on the overhang during concrete placement in order to make placement and finishing operations easier. This construction methodology could be dangerous resulting in excessive exterior girder rotation leading to a loss in deck thickness and over stress in the girders. Excessive overhang loads on the girders may cause local instabilities, global buckling, or both. In this research, the effect of overhang construction loads on the rotation of exterior plate girders during deck construction was studied. Two plate girder bridges were monitored in the field during construction in the state of Illinois and the rotation values were replicated using finite element analysis. The rotation results obtained from the field and finite element analysis of plate girder bridges showed small exterior girder rotation during bridge deck construction. These results could be used to justify relaxed bracing requirements for exterior girders during construction.
International Journal of Bridge Engineering, Vol. 5, No. 2, 2017: pp. 21-33
Rahul Kalyankar, Nasim Uddin
Abstract: This research paper focuses on simulation of vehicle bridge interaction using the spatial method of finite element modeling in order to obtain Dynamic Amplification Factor (DAF). The Simplified 3 Dimensional Finite Element Model (3D SFEM) of already verified vehicle bridge interaction was used for obtaining the DAF of US girder bridges. The effects of single and multiple heavy vehicles on the DAF of Prestressed Concrete I Girder Bridge was obtained using 3D SFEM heavy vehicle bridge interaction. Along with the number of vehicles, the effect of variable vehicle velocities and their positions on the DAF was studied. In addition to this, the combination of 3 Axle and 5 Axle vehicles over the bridge were used for obtaining DAF of the US Girder Bridges. The DAF was obtained for random vehicle scenarios where truck could travel over bridge without any synchronization. Using these variables, the true representative DAF of the bridge was obtained. From these multiple variable scenarios, an attempt was made to present the 3D SFEM as an alternative to 3D Finite Element Modeling (3D FEM) of US girder bridges, and multiple axle vehicles, so that the spatial method can be used to predict reliable responses using vehicle bridge interaction.
International Journal of Bridge Engineering, Vol. 5, No. 2, 2017: pp. 35-55
Razaq Ferhadi, Honar Issa
Abstract: Khani bridge in Zakho / Iraqi Kurdistan is under construction on Khabour River. The bridge has one simply-supported span of 63m and designed to have a non-prismatic post-tensioned concrete single-cell box girder section. This bridge, which consists of two box girders (Girder 1 for left side and Girder 2 for right side) encountered an excessive deflection during construction after removing the shores and caused a uniform deflection along the span with a maximum deflection of more than 47cm in the middle for Girder 1 bridge and 67 cm for Girder 2. This paper investigates the cause of this failure and provides the evidence to be a lessen-learned for the future of post-tensioned concrete industry in the area and improve the local bridge construction practice and management.
International Journal of Bridge Engineering, Vol. 5, No. 2, 2017: pp. 57-80
Hussain Hararwala, Savita Maru
Abstract: This paper deals with the linear static analysis of Cable Stayed Bridges with different shapes of pylons under its own weight. The cable stayed bridge is one of the modern bridges which were built for the longer spans. Therefore, there is a need of study on the behaviour of the pylons before implementing it in actual practice. For this study, the different shapes of Pylons have been compared with the bridge span dimension and other parameters are kept unvarying. The different shapes of Pylons considered for Cable Stayed Bridge are A type, H type, inverted Y type, Single pylon, Diamond shaped, Pyramid Shaped, U-Shaped & Hexagonal Shaped. The height of the pylon remains same for all the models of Cable Stayed Bridge with different shapes of Pylons. The modelling of bridge has been prepared using SAP 2000 software. For this study, the arrangement of cable stay has been taken as semi fan type as well as fan type. The study reveals the following points regarding to the behaviour of Pylons such as the Axial Force in Pylon, Bending Moment in Pylon, and Shear Force in Pylon & Deflection at the top of Pylon. This study will be helpful for make an appropriate choice for the shape of Pylon used for Cable Stayed Bridge in particular conditions.
International Journal of Bridge Engineering, Vol. 5, No. 2, 2017: pp. 81-102
Osama Mohammed Elmardi Suleiman Khayal
Abstract: A composite material can be defined as a combination of two or more materials that gives better properties than those of the individual components used alone. In contrast to metallic alloys, each material retains its separate chemical, physical, and mechanical properties. The two constituents are reinforcement and a matrix. The main advantages of composite materials are their high strength and stiffness combined with low density when compared to classical materials. Micromechanical approach is found to be more suitable for the analysis of composite materials because it studies the volume proportions of the constituents for the desired lamina stiffness and strength.
International Journal of Bridge Engineering, Vol. 5, No. 2, 2017: pp. 103-111
Abstract: Trail bridge technology is a cost effective technology that significantly enhances access to trade, markets, education, health services and improves the livelihoods of rural, poor peoples and thus contributes to poverty alleviation in Nepal. With lack of road access in past and present, foot bridge technology carries a larger scope contributing to the development of country. With the significant contribution from locals, NGOs and INGOs like Helvetas Swiss Inter co-operation, trail bridge construction in Nepal has now got a paramount importance. Still, foot bridge technology suffers from critical and challenging aspects of longevity and safety. The evolution of the modern trail bridges has been characterized by epic struggles to achieve the aim of development at local level. There have been many failures, conflicts from “people’s war” along the way, but progress continues. This article focuses and analyses a long history of modern trail bridges of Nepal which created a way to improved livelihoods, enhanced access and prosperity.
International Journal of Bridge Engineering, Vol. 5, No. 2, 2017: pp. 139-147
Rohit Kumar Mittal, Krishna Sai Vutukuru
Abstract: Arch bridges are the oldest structural monuments that are symbols of heritage and culture which needs to be protected. These bridges have been servicing on road, railway and waterway networks. The arch essentially works in compression, made possible by the horizontal reactions at the abutments which produce a normal force throughout the arch. Damage on masonry structures mainly relates to cracks, foundation settlements, material degradation and displacements. When cracks occur, generally they are localized, splitting the structures in macro blocks. Dynamic based methods to assess the damage are an attractive tool to this type of structures because they are non-destructive methods and are able to capture the global structural behavior. After detection of damage it is also equally important to select appropriate method of retrofitting which is provided through this paper.
International Journal of Bridge Engineering, Vol. 5, No. 2, 2017: pp. 113-138