Issue 2: May-Aug. 2022

Sarika Modak, Pramod Belkhode, Prasahant Maheshwary

Abstract: This study demonstrates the structural analysis and design of RCC box type bridge using manual approach (i.e. MDM method) and by computational approach (Staad-pro) using IRS - CBC codes. The structural elements (top slab, bottom slab, side wall) were designed to withstand Ultimate Load criteria (maximum bending moment and shear force) due to various loads (Dead Load, Live Load, LL surcharge, DL surcharge) and serviceability criteria (Crack width) and a comparative study of the results obtained from the above two approach has been carried out to validate the correctness of the results. Further, it was also observed that the analysis using manual calculation becomes very tedious and cumbersome and for a complex type of structure, thus it is quite a complex task to perform the analysis manually, so the use of computational method (Staad Pro and excel sheet) becomes the obvious choice for design. The results obtained using MDM method shows a good agreement with the results obtained from computational methods. Bridges are the structural components that are required for the efficient movement of Trains and locomotives and under earth embankment for crossing of water course like streams across the embankment as road embankment cannot be allowed to obstruct the natural water way. Bridges can be of different shapes such as arch, slab and box. These can be constructed with different material such as masonry (brick, stone etc.) or reinforced cement concrete. Since bridge pass through the earthen embankment, these are subjected to same traffic loads as the road carries and therefore, required to be designed for such loads. The cushion depends on rail profile at the bridge location.

International Journal of Bridge Engineering, Vol. 10, No. 2, 2022: pp. 1-14

Geetha Mackaanthottiyil Padmanabhan, Girija Krishnamma

Abstract: The development in transportation requires the faster accomplishment of various tasks, including the bridge superstructure construction. In the present study, the authors developed the twin-T shape as a standardized and modularized cross-section for prestressed post-tensioned girders of the highway bridge deck, especially across railways, based on established R & D results. This paper also focused on the solution to the longitudinal crack in the multi-girder bridge deck. The enhanced features adopted in study, like the evolved girder shape, integrating top slab and shear key and usage of high-performance concrete, reduce the depth and increase cost-effectiveness, durability and safety. High strength high-performance concrete (HS-HPC) of M75 grade is necessary for casting the girder of cross-section to satisfy the design requirements. The cross-section developed is suitable to make bridges spanning from 15m to 45m. The authors conducted an experimental study on two girder specimens of similar features of prototype girders, using the M55 mix. The modelling, simulating the experimental studies, was developed through the ABAQUS software, and the same was calibrated and validated with the experimental results.

International Journal of Bridge Engineering, Vol. 10, No. 2, 2022: pp. 15-36

Mohammad Barkhordary, Saied Tariverdilo, Afshin Movaffaghi

Abstract: Using thermal elastomeric bearings, reinforced with thin steel shims and without thick ends plates and no bending requirements in quasi-isolation design, instead of conventional seismic isolators, potentiate bridge deck to slid on its bearings during moderate to strong earthquakes. Employing potential of that fusing mechanism between substructure and superstructure which could dissipate energy through friction is called quasi isolation system. However, as quasi-isolation design benefits from that sliding, deck displacement pushes the bridge toward deck unsetting as an extreme unacceptable damage. Interestingly, the elastomeric bearing sliding behavior affected strongly by bearing geometric and elastomeric material hardness. Although, friction coefficient between elastomeric material and bearing concrete seat has been studied in many previous literatures but, consideration effects of elastomeric material hardness and some special bearing geometry on quasi isolated bridges, haven’t been studied till this paper. This study shows the elastomer hardness, bearing geometry and friction coefficient (CoF) effect on deck unsetting safety, which may violate current support length calculations.

International Journal of Bridge Engineering, Vol. 10, No. 2, 2022: pp. 37-59

Ali Zahmatkesh, Amir Baghban, Ahmad Eslami

Abstract: Nowadays, concrete is used more often than before due to its strength, durability and other desirable properties. Plasticizers and superplasticizers are used to increase performance by decreasing the amount of water in concrete. In the present study, the effect of polycarboxylate superplasticizer (PCEs) on the properties of concrete was investigated. The specimens were made with a constant mix design and the desired superplasticizer was added to it with 0.3, 0.5 and 0.7% of the cement weight. Compressive and flexural strength due to flexural of concrete specimens were measured at the ages of 7, 14, 28, and 90 days. The results showed that, increasing the amount of PCEs to a certain degree, increases the flexural and compressive strength of the specimens, especially at low ages, and then, the strength will be decreased at high amounts of PCEs. Also, the specimens’ fracture angle will be changed by increasing the PCEs.

International Journal of Bridge Engineering, Vol. 10, No. 2, 2022: pp. 61-70

Nazim Abdul Nariman, Bindesh Nunia, Shazada Omer, Elham Kamal

Abstract: The aim of this study is the prediction of deck vibration of a suspension bridge. Abaqus finite element program is being adopted to simulate the response of a suspension bridge under a strong wind. Twenty-five models based on the study of five variables are being generated to determine the vertical and torsional vibrations of the deck. A design sampling method is considered to prepare the models for numerical simulations. The regression model for the vertical and torsional vibrations of the deck would be generated supporting on three terms for their equations. The linear terms, quadratic terms, and interaction terms are utilized to represent the response of the structural system under the wind. The results of the regression models show that the prediction of the deck vibrations is an excellent representation of the numerical simulations for the same responses to a ratio of 93.47% and 92.71% for both vibrations. The regression model technique can be used further to undergo optimization for the design of the suspension bridge due to the efficiency of the regression model tool.

International Journal of Bridge Engineering, Vol. 10, No. 2, 2022: pp. 71-81