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Summary Seismic fragility assessment of highway bridges is a technique to predict the probability of the structure reaching a certain level of damage under a given seismic excitation. Vulnerable structural components have significant contributions to the failure probability of a bridge system. The effect of elastomeric isolators on the seismic fragility of highway bridges has been discussed in the literature; however, the impact of different types of rubber bearings, including natural rubber bearing, high‐damping rubber bearing, and lead rubber bearing has not been investigated yet. The objective of this study is to address this problem in detail. Seismic fragility of isolated bridges is analytically estimated by considering pier and isolation system as two major vulnerable components. Results showed that the isolation system is more fragile than the bridge pier. This finding represents those scenarios where the structure (and especially its seismic isolation system) is designed only according to the usually adopted probabilistic seismic hazard assessment, with a frequently insufficiently too short useful life. The bridge isolated by natural rubber bearing, which has the lowest lateral stiffness and energy dissipation capacity among considered bearings, is the most vulnerable system, and the bridge quipped with HDRB has the minimum risk to undergo damage. Copyright © 2016 John Wiley & Sons, Ltd.

In order to address and optimize the issues in the current assessment of bridge bearing capacity, such as the heavy workload associated with processing bridge data, the tedious modeling process, the inability to automatically calculate sub-item correction coefficients, and the lack of automatic report output and key data analysis functions, this paper has developed a cloud-based rapid calculation and analysis system for highway bridge bearing capacity. Firstly, the system is capable of quickly establishing finite element models and conducting detailed finite element calculations and analyses. Subsequently, based on field test data, it automatically calculates checking coefficients for each item and compares and analyzes the bridge’s bearing capacity. Utilizing a cloud network platform enables more convenient and rapid creation of bridge tasks and projects, key data statistical analysis, automatic report output, among other functions. Examples demonstrate that the system achieves data fusion, statistics, result verification which shifts highway bridge bearing capacity evaluation towards networking and automation while enhancing efficiency and quality in carrying capacity evaluation work.

Structural Health Monitoring (SHM) of civil engineering structures is experiencing an increasing progress in the last decades. The present work focuses on the static behavior of a highway bridge due to environmental temperature effects. The goal of the present study was to test the applicability of the satellite-based synthetic aperture radar interferometry (InSAR) for deformation monitoring of a large, curved highway bridge and to compare the obtained results with alternative measurement techniques like classical geodesy surveying and with an advanced computer simulation. Such a comparison is quite rare and provides an important insight into the accuracy, efficiency and limitations of the InSAR technique in the context of SHM. Especially interesting was the question whether the InSAR technique is suitable for blind monitoring of a cluster of bridges in the region of interest. The present study shows that a pre-knowledge about each structure can be very important for a reliable interpretation of the InSAR measurement results. The second challenge of the study was to overcome several objective difficulties of combining and comparing quite different monitoring techniques that result from different sampling rates, measurement points and other specific features and sensitivities. Nevertheless, a suitable approach has been developed and implemented in the present study for the InSAR and total station measurements, providing new results and important knowledge about novel SHM techniques.

On May 22, 2021, a 7.4 magnitude earthquake struck Maduo County (34.59° N, 98.34° E), Qinghai Province, China, with a focal depth of 17 km. The earthquake occurred near the northern boundary of the Bayan Har block. Two highway bridges, including the Yematan bridge, collapsed. Based on the analysis of the seismic damage characteristics of the Yematan bridge, a finite element model of a three-span simply supported girder bridge was established. Nonlinear analyses were performed using the bedrock wave at the bridge site during the earthquake and the seismic safety evaluation wave of the bridge as inputs to analyze the causes of seismic damage of the bridge. The results show that the large beam displacement owing to the velocity pulse and the low-frequency components of ground motion are the main causes of the bridge damage.

With the rapid development of transportation, highway bridges as a transportation hub have played an important role and become the link of economic development in the region. In recent decades, my country has built many types of highway bridges. During the construction and operation of these bridges on highways, many inspection activities are required to ensure the quality of construction and operational safety. This article mainly introduces the highway bridge test detection technology and various application methods based on big data. This paper uses big data to detect the dynamics of the highway bridge structure and establish a load test model. The model is solved by the energy-releasing method to strengthen the rigid structure of the highway bridge, evaluate the road condition, and use historical data to revise the model to improve the accuracy of the highway bridge load. The experimental results in this paper show that the highway bridge detection technology based on big data reduces accidents by 23%, and the test and evaluation results under big data show that the performance of highway bridges is excellent and meets the design.

Restrainers, being of relatively low cost and easy to install, are often used to prevent unseating of bridge spans. The potential of using superelastic shape memory alloy (SMA) restrainers in preventing such failure has been discussed in the literature; however, the impact of such smart restrainers with optimized configurations in reducing the failure probability of bridge components and system as well as the long-term economic losses given different earthquake scenarios has not been investigated yet. This study presents a probabilistic seismic fragility and long-term performance assessment on isolated multi-span simply-supported bridges retrofitted with optimized SMA restrainers. First, SMA restrainers are designed following the displacement-based approach and their configuration is optimized. Then, seismic fragility assessment is conducted for the bridge retrofitted with optimized SMA restrainers and compared with those of the original bridge and the bridges with elastic restrainers (steel and CFRP). Finally, long-term seismic loss (both direct and indirect) are evaluated to assess the performance of the retrofitted bridges in a life-cycle context. Results showed that among three considered restrainers, SMA restrainers make the bridge less fragile and help the system lower long-term seismic loss. The design event (DE, 2475-year return period) specified in Canadian Highway Bridge Design Code (CHBDC, CSA S6-14 2014) may underestimate the long-term seismic losses of the highway bridges. Under DE, the damage probability of the bridge retrofitted with optimized SMA restrainers experiencing collapse damage is only 0.7%. Under the same situation, its expected long-term loss is approximate 17.6% of that with respect to the unretrofitted bridge.

Based on the theory of highway vehicle-bridge coupled vibration analysis, a program for vehicle-bridge coupling vibration analysis of highway bridges is developed using Intel Visual Fortran language. An accurate finite element model of the axle was established by measuring the parameters of the axle test model. And an experimental system of vehicle-bridge coupled vibration was designed. Then, based on theoretical analysis and experimental research, the reliability of the analysis program and test system was verified and analyzed the influence factors of vehicle-bridge coupling vibration test were analyzed, including carriageway location, vehicle-bridge mass ratio and bridge support form were discussed. The results show that: a lateral shift of 10 cm at different lane positions has little effect on the dynamic response of the axle. The axle mass ratio is an important factor affecting the dynamic response of the axle. With a vibration response being most obvious when the mass ratio is between 0.10 and 0.16 during the test process, the vertical acceleration response of bridge bearing 1 model (one end pad bearing, the other end roller bearing) was shown to be significant. This research will provide a helpful reference for others to analyze highway vehicle-bridge coupled vibration in the laboratory.

The present study was aimed at assessing more accurately the seismic vulnerability and performance of highway bridges in an earthquake-damaged area. Based on mathematical statistics (data collection) and a probability model, (i) survey data for 2134 bridges in 22 highway sections (47 sub-sections) affected by the Wenchuan earthquake on May 12, 2008 were obtained and analysed, (ii) Gaussian and exponential regression models were developed, (iii) the empirical seismic-damage vulnerability function, plane, surface and curve model of the 22 highway sections with sample number and failure ratio were established, and (iv) a regression parameter matrix was constructed considering the empirical seismic-damage data. Using the method of probability exceedance, the bridge vulnerability curve models considering the seismic-damage exceedance probability of each section were analysed, and a parameter matrix model (mean seismic-damage index) was proposed to evaluate and predict the seismic vulnerability of regional bridges. Based on creating the actual seismic-damage sample database, vulnerability point-cloud models of the 22 highway bridges were constructed, and the vulnerability probability matrix, function, curve and point-cloud model of each highway section can be used to evaluate and estimate the vulnerability of regional bridges in the future.

At present, highway and bridge projects in China are in full swing. In the process of multi project construction of highway and bridge, it is of great significance to study the project scheduling. On the basis of fully analyzing the specific characteristics of multi projects in highway and bridge construction, this paper studies the problem of “fixed duration resource balance (RB)” based on genetic algorithm (GA). Combined with the specific characteristics of multi projects in highway and bridge construction, it establishes an optimization model, and proposes the process of GA to solve the problem of multi RB in construction projects. When considering the multi project resource balance optimization (RBO) problem of highway and bridge construction, the GA is used to solve the problem. The results show that the model is effective for the multi project RB problem of highway and bridge construction. At the same time, it proves that it has great advantages to consider the RB of multiple projects of highway and bridge construction from the new perspective of resource scheduling cost.

Bridges are one of the most critical and costly structures on road networks. Thus, their integrity and operation must be preserved to prevent safety concerns and connectivity losses after seismic events. Recent large-magnitude earthquakes have revealed a series of vulnerabilities in multi-span highway bridges. In particular, skewed bridges have been severely damaged due to their susceptibility to developing excessive in-plane deck rotations and span unseating. Although seismic design codes have been updated to prescribe larger seating lengths and have incorporated unseating prevention devices, such as shear keys and cable restrainers, research on the seismic performance of skewed bridges with passive energy-dissipation devices is still limited. Therefore, this study focuses on assessing the effectiveness of implementing hysteretic dampers on skewed bridges. With that aim, dampers with and without recentering capabilities are designed and incorporated in representative Chilean skewed bridges to assess their contribution to seismic performance. Three-dimensional nonlinear finite element models, multiple-stripe analysis, and fragility curves are utilized to achieve this objective. The results show that incorporating bidirectional dampers can effectively improve the seismic performance of skewed bridges at different hazard levels by limiting in-plane deck rotations independently of their skew angle. Additionally, the influence of external shear keys and damper hysteretic behavior is analyzed, showing that these parameters have a low influence on bridge performance when bidirectional dampers are incorporated.