Bridge Structures - Volume 20, issue 3-4

Authors: Mahmoud, Khaled M.

Article Type: Editorial

DOI: 10.3233/BRS-240229

Citation: Bridge Structures, vol. 20, no. 3-4, pp. 93-94, 2024

Authors: Ouanani, Mouloud | Sandjak, Khaled | Tiliouine, Boualem

Article Type: Research Article

Abstract: The progressive failure of the nonlinear irregular Cable-Stayed Bridges (CSBs) under Spatial Variability of Ground Motions (SVGM) counting seismic wave propagation, incoherence effect and site-response effect is investigated. A spectral representation method is used in order to develop a computer code. This code is used to simulate SVGM time histories to be compatible with an overall coherency function and a target response spectrum, A three-dimensional Finite Element Model (FEM) of an asymmetric bridge: the Beni Haroun cable-stayed bridge (CSB) (North Eastern Algeria) is developed in order to include the effects of the main components of SVGM on response parameters in …terms of variations of absolute maximum vertical displacements and flexural moments along the deck and on height of short and tall pylons of study CSB, in particular, nonlinear bridge response quantities are examined in terms of rotational ductility demands at the ends of the short and tall piers of the bridge under all components of SVGM. The numerical results are comforted with those obtained assuming uniform seismic excitations. The analysis results reveal, among others, that the bridge responses are very sensitive to the SVGM, with site-response effects being more critical for bridge response than those of incoherence components and wave propagation. As a general trend, it is showed that the assumption of uniform excitation results in much lower ductility demands on bridges than incoherence and site SVGM components and that the latter should be considered for the seismic response assessments and progressive seismic failure studies of irregular cable-stayed bridges. Show more

Keywords: Irregular cable-stayed bridges, non-linear behaviour, SVGM, wave passage, incoherence effect, site effect, Progressive failure

DOI: 10.3233/BRS-240225

Citation: Bridge Structures, vol. 20, no. 3-4, pp. 95-110, 2024

Authors: Li, Jie | Hou, Yazhao | Liu, Wei | Luo, Jun | Wang, Bangrui

Article Type: Research Article

Abstract: Based on a single box seven chamber steel box continuous bridge, a plate element model of the bridge is established using finite element software for asphalt paving on the wide steel box girder bridge deck. The distribution of instantaneous high-temperature temperature field during asphalt paving is analyzed in detail. On this basis, the shear lag effect of paving temperature load and its influencing factors are studied. The results indicate that there are significant temperature changes in the paving layer and steel box girder during the asphalt paving process. The temperature field of the steel box girder in the paving area …is significantly affected by the paving temperature. After the temperature of the steel box girder reaches 103°C, the temperature decrease rate of the flange plate is greater than that of the box chamber temperature. The temperature drop rate at the junction of the top plate, web plate, transverse partition, and flange plate is faster than in other areas. During the first 1000 seconds of paving, the temperature of the paving layer rapidly decreases, with a maximum rate of decrease reaching 21°C/min, and then the rate of temperature decrease gradually decreases. From the beginning of asphalt paving to the middle of the span, the shear lag coefficient at the edge web of the middle span gradually increases from 0.83 to 1.09. The shear lag coefficient of the middle web gradually decreased from 1.12 to 1.05, and then increased to 1.09. After asphalt paving to the mid span, the shear lag coefficients at the edge and middle web plates suddenly change to 0.64 and 0.79, respectively. Subsequently, the shear lag coefficients of the two gradually increased to 0.80 and 1.01, respectively. At the time of 3000 seconds of paving, the steel box girder experiences maximum stress. At this moment, when the temperature of the paving material is higher, the wind speed is lower, the paving thickness is greater, and the paving speed is higher, the stress in the paving area will be greater. However, under the maximum stress, the temperature of the mixture, paving thickness, and paving speed have little effect on the shear lag coefficient of the top plate in the paving area. Show more

Keywords: Wide steel box girder, asphalt paving on bridge deck, instantaneous high temperature, temperature field, shear lag effect

DOI: 10.3233/BRS-240227

Citation: Bridge Structures, vol. 20, no. 3-4, pp. 111-125, 2024

Authors: Lagerkvist, Johan | Berrocal, Carlos Gil | Carlsson, Fredrik | Rempling, Rasmus

Article Type: Research Article

Abstract: Bridges must be designed to ensure safety for all users. At the same time, the design should be performed with an appropriate risk level. In Sweden, Soil-Steel Composite bridges (SSCB) are the most common bridge type. For SSCB, local verification of Load Model 1 in Eurocode is most often governing the design. The objective of this study was to investigate whether local verification of LM1 load case could be modified without decreasing the agreed risk level in Eurocode. Weight in motion measurements from real traffic were extrapolated with Rice formula. Monte Carlo simulations were used to simulate the 1000-year return …period event to obtain the acceptable risk level as prescribed in Eurocode. The results show that the local verification of LM1 is conservative, considering the acceptable risk level in Eurocode. With a modified implementation of local verification, this paper shows that a potential saving of up to 14% in terms of economic cost and CO2 -equivalents is possible. A modified implementation of local verification of LM1 in Eurocode for SSCB is proposed, which could reduce the climate impact by up to 14% associated to the construction of new SSCB in Sweden. Show more

Keywords: Soil-steel composite bridges, climate reduction, probabilistic risk analysis, Monte Carlo simulations, rice formula

DOI: 10.3233/BRS-240228

Citation: Bridge Structures, vol. 20, no. 3-4, pp. 127-140, 2024

Authors: Shedge, Hrishikesh N. | Kumar, Manoj

Article Type: Research Article

Abstract: Integral abutment bridges (IABs) are a family of jointless bridges that have gained popularity owing to their simplified designs and sustainable construction practices. IABs are small- and medium-span bridges that do not have expansion joints or bearings, thereby reducing the cost of maintenance. The span of IABs is primarily dependent on the magnitude of the thermal stresses considered during the design process. However, the adoption of IABs has been limited globally because of the inherent complexity of the design caused by the large number of indeterminacies originating from rigid connections and soil-spile interactions. This has led to variations in the …design of IABs among transportation agencies worldwide. This literature review aims to highlight the variations in major IAB projects constructed worldwide. Additionally, the bibliographic analysis performed for IABs identified key topics studied by researchers, which are discussed in detail in the current state-of-the-art. The objective of this literature survey is to provide practical bridge designers and researchers with an understanding of previous and ongoing developments in IABs. Show more

Keywords: Integral abutment bridge (IAB), H-pile, soil-spring interaction, dynamic analysis, thermal displacements, bridge span

DOI: 10.3233/BRS-240226

Citation: Bridge Structures, vol. 20, no. 3-4, pp. 141-155, 2024