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Purpose – The purpose of this study is to develop a numerical framework to predict the time-dependent probability of failure of a bridge subjected to multiple vehicle impacts. Specially, this study focuses on investigating the inter-relationship between changes in life-cycle parameters (e.g., damage size caused by vehicle impact, loss of initial structural capacity, and threshold intervention) and bridges probability of failure.

Design/Methodology/Approach – The numerical procedure using MATLAB program is developed to compute the probability failure of a bridge. First, the importance and characteristics of life-cycle analysis is described. Then, model for damage accumulation and life cycle as a result of heavy vehicle impacts is discussed. Finally, the probability of failure of a bridge subjected to vehicle impacts as a result of change in life-cycle parameters is presented.

Findings – The results of study show that damage size caused by both vehicle impacts and loss of initial structural capacity have a great impact on the long-term safety of bridges. In addition, the probability of failure of a bridge under different threshold limits indicates that the structural intervention (e.g., repair or maintenance) should be undertaken to extend the service life of a bridge.

Research Limitations/Implications – The damage sizes caused by heavy vehicle impacts are based on simple assumptions. It is suggested that there would be a further study to estimate the magnitude of bridge damage as a result of vehicle impact using the full-scale impact test or computational simulation.

Practical Implications – This will allow much better predictions for residual life of bridges which could potentially be used to support decisions on health and maintenance of bridges.

Originality/Value – The life-cycle performance for assessing the time-dependent probability of failure of bridges subjected to multiple vehicle impact has not been fully discussed so far.

The aerodynamic load caused by high-speed train operation may lead to severe vibration of the pedestrian bridge, thus causing great safety hazards. Therefore, this study aims to investigate the aerodynamic loading characteristics of a pedestrian bridge when a high-speed train passes over the bridge, as well as to evaluate the vibration response of the aerodynamic loads on the bridge structure.

High-speed trains are operated at three different speeds. The aerodynamic pressure load characteristics of high-speed trains crossing a pedestrian bridge are investigated by combining a nonconstant numerical simulation method with a dynamic modeling test method, and the vibration response of the bridge is analyzed.

The results show that when a high-speed train passes through the pedestrian bridge, the pedestrian bridge interferes with the attenuation of the pressure around the train, so that the pressure spreads along the bridge bottom, and the maximum positive and negative pressure peaks appear in the center area of the bridge bottom, while the pressure fluctuations in the bridge entrance and exit areas are smaller and change more slowly, and the pressure attenuation of the bridge bottom perpendicular to the direction of the train’s operation is faster. In addition, the pressure fluctuation generated by the high-speed train will lead to a larger vertical response of the bridge structure in the mid-span position, and the main vibration frequency of the bridge structure ranges from 8 to 10 Hz, and the maximum value of the vertical deformation amplitude is located in the mid-span region of the bridge.

This paper analyzes the flow field distribution around the train and at the bottom of the bridge for the evolution of the flow field when the train passes through the bridge at high speed, and conducts a finite element dynamic analysis of the bridge structure to calculate the vibration response of the bridge when the train passes through at high speed, and to evaluate the comfort of the passengers passing through the high-speed railroad bridge.

It evaluated the seismic vulnerability based on fewer factors by presenting the effectiveness of seismic and structural parameters. The proposed method first demonstrated the effect of earthquake ground motion inputs on predicting the slight, moderate, extensive and collapse limit states and confirmed the method’s efficiency. The fragility curves illustrated with the approach of the present study are compared with the traditional techniques, such as analytical methods.

Based on the different macro- and micro-structural characteristics and the earthquake records, achieving a certain relation from regression analysis using artificial neural networks (ANNs) is difficult. With this background in mind, the present study aimed to compare the proposed model of the considered bridge with the analytical and ANN results. After statistical analysis and estimation of the most effective factors in predicting responses from the proposed approach, two-parameter two- and three-dimensional fragility curves are extracted.

Due to the structural differences between horizontally curved bridges, the methodology does not require any classification of bridge classes to predict responses. For a specific L/R of the bridge, the parameters cumulative absolute velocity (CAV) and Sa (T1) can provide a good estimate of the seismic fragility curves, and the proposed approach with less parameter assignment also leads to good results. With less computational effort, fragility curves can be illustrated.

The proposed method demonstrated the ability to accurately estimate the occurrence and non-occurrence limit states while maintaining a low computational cost and the derivation of a curved bridge’s seismic fragility curve.

To develop an analysis methodology to evaluate the dynamic behaviour and fatigue assessment of highway bridges due to vehicle passage on irregular pavement surfaces. The approach considers the non-deterministic nature of the parameters of the vehicle-bridge system using Monte Carlo simulations.

In the proposed approach, 11 vehicle-bridge system parameters are modelled as random variables with predefined probability distributions. The dynamic analysis considers the vehicle-structure-pavement interaction, in which road surface roughness is defined based on the use of the power spectral density function, as an expression of the road surface random irregularities. Based on the results of the dynamic analysis, a fatigue assessment is performed. To demonstrate the applicability of the methodology, a case study of a 40-m-span steel-concrete composite highway bridge was selected, considering two levels of pavement quality.

The results reveal that vehicle speed, sprung masses, bridge mass and rear axle and tire stiffness are the parameters that most influence vertical displacement, bending stress and fatigue life. Numerical simulations showed that the pavement deterioration reduced fatigue life by up to 98.6%, increasing the failure probability.

The dynamic behaviour and fatigue of a highway bridge are evaluated by means of vehicle-structure interaction analyses, in which the randomness of 11 parameters of the vehicle-bridge system is simulated. This includes dynamic parameters of the suspension and tires, whose variability is rarely considered due to the difficulty in obtaining sample data.

A bridge network is a major capital asset that requires continuing investment in order to maintain the network within acceptable limits of safety and serviceability. Ranking and prioritizing procedures have been widely used by several departments of transportation to select bridges for intervention and to distribute the available funds among competing projects. The available ranking and prioritizing procedures have various drawbacks, and an improved, rational ranking and prioritizing procedure is needed. The paper aims to address these issues.

The requirements and characteristics of an innovative ranking and prioritizing method are identified during interviews with professionals involved in bridge management. Based on these requirements, multi‐attribute utility theory (MAUT) is selected to develop the method. A technique to develop utility functions based on the analytical hierarchy process (AHP) is discussed. A hierarchy structure that captures the decision‐making elements is presented. A case study is used to demonstrate the applicability and the validity of the proposed ranking method.

The research findings have identified the decision objectives and the criteria essential to rank and prioritize bridge projects, and these are included within a framework to rank and prioritize bridge projects while incorporating experts' input in the process.

The proposed framework includes weights for the various objectives and recommends utility functions to evaluate the different attributes. In addition, the framework provides flexibility to adjust the weights and to modify the utility functions to reflect network‐specific characteristics. This method can be used by departments of transportation to rank bridges in a network, even incorporating conflicting criteria, and it can be integrated within an already implemented bridge management methodology.

Ranking and prioritizing projects are essential steps in bridge management. Current methods for ranking and prioritizing bridge projects are associated with various drawbacks. This paper proposes an innovative ranking method for bridge networks, based on MAUT. This theory provides flexibility for the decision makers in expressing their degree of satisfaction with each bridge attribute.

Infrastructure maintenance management has become a challenge field for civil engineers and government managers because of the increasing number of deteriorated structures, their complicated spatial locations, the improved service requirements, the limited maintenance budgets and so on. Therefore, maintenance management approaches have been developed for civil infrastructures such as bridges and roads over the past several decades, but most of such approaches focused on one specific structure only – project‐level maintenance management. Now, there are increasing demands and appropriate conditions for network‐level maintenance management for civil infrastructure systems. Aims to explore such a maintenance management approach by integrating and applying the current information technologies, which include the database management system, geographic information system, genetic algorithm and the Internet. Several possible applications of each technology are discussed for solving real‐world problems.

This paper aims to obtain the further and overall generation about the static characteristics of the structure for the better application of the structure.

Through nonlinear finite element simulation, serials of comparative analyses are performed on this structure and other three assumed structures, which illustrate the effect of the main part of the structure on the structural static properties. Meanwhile, adopting the first order method, spatial cable force optimization makes the structural mechanic more rational.

Under same level stress, this three‐main‐truss and three‐cable‐plane bridge could save almost 38.8 percent vertical chords materials consumption at least. In contrast, this bridge has a lower lateral torsional stiffness, considering the key to raise the lateral and torsional stiffness is enhancing axial stiffness of plane bracing, the suitable plane bracing members area is twice as the original area. After rational optimization, the cable tension ratio between the mid‐cable plane and the two side‐cable planes ranges from 1.09 to 1.14.

The work in this paper of the comparative analysis could give other engineers a way to a deep analysis method for the structural analysis, especially in civil engineering. The conclusions would provide other designers some applied advice.

Bridge lines represent a way for designers to expand their business, because typically designer merchandise is supplied to a limited number of stores. With bridge lines, the prices are lower and the line can be supplied to more stores. The bridge line market has been rapidly evolving in recent years. Retailers are paying close attention to this sector, particularly in the light of the stagnant demand for more expensive designer ready‐to‐wear collections. Despite the general economic recession, the culture of wearing fashion in the 1990s has paved the way to the growth of bridge lines.

The potential threats of extreme events to highway bridges have received increased attention from government agencies, the engineering and construction communities, and the traveling public. These events include terrorist attacks as well as human‐induced and natural hazards such as earthquakes, explosions, fires, floods, and hurricanes. To respond to the potential threats on highway bridges, a research project was conducted to identify rapid bridge replacement processes, techniques, and needs for improvements.

To achieve the research objectives, a detailed case study of previous bridge replacement following an extreme event was conducted. The case study was performed using a three‐step approach. First, the research team reviewed the literature related to the case. Second, the research team interviewed the people who were involved with the case via the telephone. Third, the research team conducted a written survey to gain knowledge about the previously unanswered questions and additional information related to the case.

After studying the case, lessons learned were identified first. Then, the research team determined the processes that were used in the rapid bridge replacements and the needed improvements so that the research community could investigate new technologies to advance current practices.

The lessons learned could be of benefit to government agencies who are responsible for development of the enhanced emergency response plans for highway bridges, and engineering and construction communities who are responsible for design and reconstruction of the damaged bridges. The development of new technologies, if successful, will ultimately enhance the capability of rapid bridge replacement after extreme events.

The purpose of this evaluative study is an attempt to understand the bridging programme by drawing on the work of Wadsworth and to prove that a place still exists for bridging programmes within the University of Johannesburg and the higher education sector in South Africa.

The research study is both quantitative and qualitative in nature. An interpretative naturalistic approach is used to understand the thinking and experiences of the students in the bridging programme.

This study reveals, first that a causal relationship exists between the length of the bridging programme and how long students take to successfully complete the national diploma in engineering. Second, that bridging programmes can contribute to the success of engineering students who want to successfully complete their engineering studies within the designated timespan. Third, that, if designated staff are utilized in the teaching of the bridging programmes, students are able to receive the necessary support which enables them to successfully complete the national diploma in engineering.

This research reveals that bridging programmes, implemented over an extended period, are valuable because they allow student access to higher education and lay a solid foundation by equipping them with the knowledge and skills necessary for success in mainstream diplomas such as the national diploma in engineering. These programmes put into practice the shift of policy emphasis from “access” to “success”, which has implications not only for the University of Johannesburg but also for the higher education sector in South Africa.