Hasil untuk "Bridge engineering"

Junqing Xue, B. Briseghella, F. Huang et al.

Abstract Due to the superior mechanical properties and durability, the ultra-high performance concrete (UHPC) has been widely used for the design of various types of structures, while research on its performance has been rapidly growing in the last five years. While the application of UHPC in bridge engineering is limited due to its higher cost, relatively little is known about the mechanical behavior of UHPC in different bridge components. In order to inform future research needs, this paper provides a comprehensive review of the properties of UHPC and its application in bridge engineering. Applications in various bridge components, such as the piers, girders, decks, and link slabs used for jointless bridges have been summarized. This review also discusses future research on optimized UHPC mix designs considering economic cost and its applications in both jointed and jointless bridges.

Zhiguo He, Wentao Li, H. Salehi et al.

Mi Zhou, Wei Lu, Jianwei Song et al.

Abstract Ultra high performance concrete (UHPC) is a type of cement-based composite, which is the most innovative product in concrete technology during the last 30 years. The advantages of UHPC compared with the common concrete, such as superior mechanical performance, excellent anti-seismic property and resistance against environmental degradation are introduced in the paper. The paper begins by briefly introducing its history of development and technical performance. Then, the research and application situation of UHPC in bridge engineering are discussed and many practical applications in bridge bearing component, bridge deck pavement and bridge joints are summarized. Moreover, the paper analyzes advantages and shortcomings of UHPC and the constraints for the application of UHPC in bridge engineering. In addition, the performance of UHPC in seismic resistance and anti-explosion is briefly summarized. Based on these works, prediction of UHPC further research in the future is prospected.

B. Graybeal, E. Brühwiler, Byung-Suk Kim et al.

Abstract Ultrahigh-performance concrete (UHPC) offers significant potential to address a variety of needs in bridge design, construction, and performance enhancement. Bridge owners have shown willi...

Song Honghong, Yang Gang, Liao Haijiang et al.

N. Vatin, Gunasekaran Murali, Lei Wang et al.

Ultra-high-performance concrete (UHPC) is a form of cementitious composite that has been the most innovative product in concrete technology over the last three decades. Ultra-high-performance concrete has been broadly employed for the design of numerous forms of construction owing to its excellent mechanical characteristics and durability, and studies on its behavior have grown fast in the last decades. While the utilization of ultra-high-performance concrete in bridge engineering (BE) is limited owing to its high costs, little is recognized about the utilization of UHPC in various BE elements. As a result of these issues, a comprehensive review of the current UHPC development trends should be conducted to determine its present state and perspective. This study presents a review of the state-of-the-art UHPC applications in BE. This review also discusses the current status, limitations, challenges, and areas for the further investigation of UHPC in BE. The aim of this research to help various construction stakeholders understand the distinctive characteristics, benefits, and barriers to the broad utilization of ultra-high-performance concrete applications. The understanding of UHPC will aid in increasing its entire market share in both the national and worldwide building sectors.

Chunxiang Qian, Wenxiang Du, Yudong Xie et al.

With the growing demand for large-scale infrastructure development in China—such as deep-sea, deep-underground, and urban subsurface projects—combined with the widespread use of general-purpose raw materials, there is an urgent need for more precise crack control technologies in concrete. This need stems from the imperative to reduce unnecessary material consumption and environmental impact caused by excessive safety margins. To address this, a set of governing equations that account for the mutual feedback between temperature and humidity was first proposed. A non-constant form of the diffusion coefficient was introduced, alongside latent heat terms and unsteady-state heat source terms, to establish a hygrothermal coupling model. This model was further enhanced by incorporating the effects of creep relaxation, reinforcement constraint, structural restraint, and thermal conduction characteristics of formwork, thereby forming a comprehensive multi-field coupling evaluation framework that encompasses the temperature field, moisture content field, strain field, and cracking index field. Subsequently, the proposed theoretical framework was applied to representative engineering scenarios, including large-scale concrete foundation slabs, bridge bearing platforms, large-area long-span side walls and prefabricated tunnel segments. The accuracy and reliability of the model were validated through comparisons between simulation results and field-monitored data. The results demonstrate that this method effectively overcomes the technical limitations of traditional concrete crack prediction models, particularly those relying on constant parameter assumptions and decoupled field interactions. It offers a practical and robust approach for engineering applications, providing a novel perspective for precision crack control in concrete and contributing to the broader goals of sustainability and resource efficiency.

Shangkai Liu, Kai Tong, Fengmin Chen et al.

The reliability of high-strength bolted connections is critical to the safety of large-scale engineering structures. This study proposes a non-contact quantitative method for detecting bolt loosening based on the self-magnetic flux leakage (SMFL) effect. Systematic experiments were carried out on M14-12.9 bolts, using nine independent specimens tested under six torque levels, to reveal the intrinsic relationship between bolt preload and the “magnetic valley” feature of the surface leakage field. For quantitative evaluation, the absolute value of the differential peak magnetic field, |ΔPMF|, is defined as the core feature parameter. The results show that, in the reference specimen group, |ΔPMF| exhibits a pronounced linear relationship with the applied torque (<i>R</i>² > 0.96), and the corresponding linear regression parameters display good consistency across the nine specimens (RSD ≈ 4%). Comparative tests on two additional bolt specifications clarify how bolt strength grade and geometric size influence the detection sensitivity and linearity. To address lift-off effects, measurements on a representative specimen at four lift-off heights were used to construct a simplified bivariate linear compensation model, which significantly reduces lift-off-induced bias within the working range <i>h</i> = 10–16 mm. Finally, a hierarchical diagnostic scheme for bolt loosening that incorporates lift-off compensation is established on the basis of |ΔPMF|, providing a feasible approach for rapid assessment of bolt loosening under complex service conditions.

Yueyue Gao, Zuo Xiao, Minghuan Cui et al.

Organic solar cells (OSCs) exhibit complex charge dynamics, which are closely correlated with the dielectric constant (ɛr) of photovoltaic materials. In this work, a series of novel conjugated copolymers based on benzo[1,2‐b:4,5‐b′]difuran (BDF) and benzotriazole (BTz) is designed and synthesized, which differ by the nature of π‐bridge from one another. The PBDF‐TF‐BTz with asymmetric furan and thiophene π‐bridge demonstrates a larger ɛr of 4.22 than PBDF‐dT‐BTz with symmetric thiophene π‐bridge (3.15) and PBDF‐dF‐BTz with symmetric furan π‐bridge (3.90). The PBDF‐TF‐BTz also offers more favorable molecular packing and appropriate miscibility with non‐fullerene acceptor Y6 than its counterparts. The corresponding PBDF‐TF‐BTz:Y6 OSCs display efficient exciton dissociation, fast charge transport and collection, and reduced charge recombination, eventually leading to a power conversion efficiency of 17.01%. When introducing a fullerene derivative (PCBO‐12) as a third component, the PBDF‐TF‐BTz:Y6:PCBO‐12 OSCs yield a remarkable FF of 80.11% with a high efficiency of 18.10%, the highest value among all reported BDF‐polymer‐based OSCs. This work provides an effective approach to developing high‐permittivity photovoltaic materials, showcasing PBDF‐TF‐BTz as a promising polymer donor for constructing high‐performance OSCs.

Shanshan Wu, Mohd Zamri Ramli, S. P. Ngian et al.

This paper reviewed the application of parametric building information modelling (BIM) in bridge engineering, highlighting its contributions to improving workflows, fostering interdisciplinary collaboration, enhancing interoperability, and optimizing design processes. It examined how parametric modeling facilitated rapid design exploration and simulation-driven optimization through flexible, rule-based relationships. Case studies illustrated the use of parametric techniques to create customizable bridge components and assemblies, which enhanced decision-making through seamless integration with analysis tools. Furthermore, this study discussed forward design, an emerging trend that improved collaboration efficiency and cost control by establishing early computational definitions, as opposed to following traditional document-driven design methods. It also emphasized the importance of open standards, such as Industry Foundation Classes (IFC), for information exchange, noting the need to extend these standards for specialized infrastructure domains. Finally, it outlined future research directions, including scalability, multimodal data integration, and generative design, aiming to fully leverage the potential of BIM throughout the lifecycle of bridges. Parametric BIM boosts teamwork and speeds up bridge design, leading to more efficient construction processes. Customizable bridge components allow for better decision-making and integration with engineering analysis tools. Open standards can enhance information sharing, paving the way for more innovative bridge design approaches. Parametric BIM boosts teamwork and speeds up bridge design, leading to more efficient construction processes. Customizable bridge components allow for better decision-making and integration with engineering analysis tools. Open standards can enhance information sharing, paving the way for more innovative bridge design approaches.

Jinhua Wang, Nengzhong Lei, Xiaolin Tang et al.

Taking the shield construction of Xiamen Metro Line 2 tunnel side-crossing the Tianzhushan overpass and under-crossing the Shen-Hai Expressway as the engineering background, FLAC3D 6.0 software was used to examine the deformation of adjacent structures based on shield construction parameters in upper-soft and lower-hard strata. The reliability of the numerical simulation results was verified by comparing measured and predicted deformations. The study results indicate that deformation of the pile will occur during the construction of the tunnel shield next to the pile foundation. The shape of the pile deformation curve in the horizontal direction is significantly influenced by the distance from the pile foundation to the adjacent tunnel’s centerline, as well as by soil bin pressure, grouting layer thickness, and stress release coefficient. During the tunnel shield construction beneath the expressway, increasing the soil bin pressure, the grouting layer thickness, and reducing the stress release coefficient can effectively minimize surface deformation and differential settlement on both sides of the deformation joints between the bridge and the roadbed. The practice shows that, by optimizing shield construction parameters in upper-soft and lower-hard strata, the deformation of nearby bridges and pavements can be kept within allowable limits. This is significant for reducing construction time and costs. The findings offer useful references for similar projects.

Junwei Wang, Fuqiang Zhao, Zihan Guo et al.

Composite rubber bearing is an important supporting component in bridge structure system, its aging and shear performance will affect the safety of the whole structure. However, due to the complexity of LRB specifications and sizes, the shear properties of aging LRB under different parameters were studied. In this study, the thermal aging and shear tests of 12 LRBs of the same specifications were first carried out, and the test results were taken as a reference, and the finite element model was established to select the constitutive model and determine the parameters, and finally the constitutive model and parameters consistent with the test were determined. Then, LRBs with different shape coefficient, diameter and number of layers were established, and shear simulation was carried out respectively to compare with the shear performance of the test supports, and the changes of parameters such as maximum shear force, energy dissipation, equivalent shear stiffness, initial sliding displacement and sliding distance generated by LRBs of different specifications at different shear stages were studied. The results show that for LRB of the same specifications, aging does not affect the maximum shear force, but the hardness and energy dissipation of rubber material increase with the aging time, and the initial sliding distance decreases with the aging time. For LRB with different parameters, under the same aging time, the maximum shear force and energy dissipation increase with the increase of shear deformation, and the equivalent shear stiffness decreases with the increase of shear degree. The maximum shear force, energy dissipation and initial shear stiffness of LRB increase with the increase of shape coefficient and diameter. The number of layers of the LRB does not affect the maximum shear force, but the energy dissipation increases with the increase of the number of layers, and the equivalent shear stiffness decreases with the increase of the number of layers. The larger the shape factor, diameter and layer number of LRB, the more likely it is to slip. Therefore, the influence of bearing parameters on the shear performance of LRB should be considered comprehensively when designing LRB in actual engineering.

LUO Shixin, LUO Hongming, ZOU Fei et al.

Highway spoil features a wide range of particle sizes and poor gradation, and their strength characteristics serve as key factors affecting the stability of spoil slopes. To explore the relationship between fractal characteristics of particle size and strength, this study examined 21 spoil sites along the Guizhou section of the Duyun‒Shangri-La Expressway. Based on the field investigation, particle size analysis tests, and laboratory shear tests, the particle composition and shear strength parameters of spoil were obtained. Based on fractal theory, the fractal characteristics of particle size under different gradation scaling methods were analyzed, and the relationship between shear strength parameters and the fractal dimensions of particle size was discussed. A formula for estimating the shear strength parameters of spoil was established. The results show that the particle composition of spoil varies significantly depending on their source and degree of weathering. Spoil from roadbeds and strongly weathered spoil generally exhibit unimodal distributions, while spoil from tunnels and with moderate weathering tend to exhibit bimodal distributions. The fractal dimension shows a strong correlation with both the internal friction angle and the fine particle content (mass percentage of particles smaller than 5 mm). When the fine particle content is ≤20%, the fractal dimension increases with the increasing of fine particle content, while the internal friction angle decreases with increasing fractal dimension. When the fine particle content exceeds 20%, the fractal dimension decreases with increasing fine particle content, and the internal friction angle increases with increasing fractal dimension. The proposed estimation formula for shear strength parameters was validated through case studies, and the strength parameters can be estimated based on particle composition, providing a reference for the stability assessment of spoil sites.

Laiping Fang, Qi Meng, Yuan Zhang et al.

Designing mitochondria-targeting phototheranostic agents (PTAs), which can simultaneously possess exceptional and balanced type-I photodynamic therapy (PDT) and photothermal therapy (PTT) performance, still remains challenging. Herein, benzene, furan, and thiophene were utilized as π bridges to develop multifunctional PTAs. STB with thiophene as a π bridge, in particular, benefiting from stronger donor-accepter (D-A) interactions, reduced the singlet-triplet energy gap (ΔES1-T1), allowed more free intramolecular rotation, and exhibited outstanding near-infrared (NIR) emission, effective type-I reactive oxygen species (ROS) generation, and relatively high photothermal conversion efficiency (PCE) of 51.9%. In vitro and in vivo experiments demonstrated that positive-charged STB not only can actively target the mitochondria of tumor cells but also displayed strong antitumor effects and excellent in vivo imaging ability. This work subtly established a win-win strategy by π bridge engineering, breaking the barrier of making a balance between ROS generation and photothermal conversion, boosting a dual enhancement of PDT and PTT performance, and stimulating the development of multimodal imaging-guided precise cancer phototherapy.

Jie Yang, Quan-Xin Li, Zesheng Li

Maojun Duan, Fenghui Dong, Jiaqing Wang

As the core course of civil engineering, the teaching quality of bridge engineering and the learning effectiveness of students are crucial for the construction of bridge engineering. The traditional teaching of bridge engineering courses tends to be teacher-centered, with learning as a supplement, and therefore is commonly referred to as teacher-centered. This article analyzes the drawbacks of the teacher-centered teaching model and proposes a student-centered holographic teaching method in the teaching practice of bridge engineering courses. By reconstructing the learning content and constructing a holographic information field from a comprehensive perspective of digital, physical, and humanistic aspects, a teacher–student learning community guided by teachers and deeply participated in by students is established. From the perspective of integrating life experience, professional knowledge cognition, and engineering philosophy thinking, the learning effect of students is made high order, innovative, and challenging. The improved analytic hierarchy process (AHP) was used to evaluate the student-centered holographic teaching concept, and the results showed that adopting a multidimensional and multi-level holographic teaching method has great practical significance in promoting the establishment of student knowledge systems and the development of diversity.

Siyuan Zhang, Bo Yu, Ruipu Li et al.

To deeply explore the development path of intelligent construction of bridge engineering safety management under the background of intelligent construction in China’s construction industry, based on the technical characteristics of bridge engineering and the difficulties of safety management, this paper analyzes the current situation and implementation path of intelligent development of bridge engineering in China, discusses the supporting role of modern information technology on intelligent safety management of bridge engineering, and finally analyzes the future development challenges of intelligent safety management of bridge engineering. To provide a reference for the safety management of future bridge engineering projects and rapidly improve the overall safety production level of the industry.

Ji Qian, Peiyun Zhang, Yongqiang Wu et al.

The corrosion of reinforced concrete (RC) is one of the most serious durability problems in civil engineering structures, and the corrosion detection of internal reinforcements is an important basis for structural durability assessment. In this paper, the appropriate frequency required to cause excitation signals in the specimen is first analyzed by means of frequency dispersion curves. Subsequently, the effectiveness of five damage indexes (DIs) is discussed using random corrosion in finite elements. Finally, guided ultrasonic wave (GUW) tests are conducted on reinforcement and RC specimens at different corrosion degrees, and the test results are verified using a theoretical corrosion model. The results show that the larger the covered thickness is at the same frequency, the higher the modal order of the GUW in the frequency dispersion curve is, and the smaller the group velocity is. The SAD is the most sensitive to the corrosion state of the reinforcement compared with the other DIs, and it shows a linear increasing trend with the increase in the corrosion degree of the reinforcement. The SAD values of the RC specimens showed a three-stage change with the increase in the corrosion time, and the time until the appearance of corrosion cracks was increased with the increase in the covered thickness. It can be seen that increasing the covered thickness is an effective method to delay the time until the appearance of corrosion cracks in RC specimens.

Yuanliang Yang, Yi-Chen Zhu, C. Cai

The concept of digital twins in bridge engineering is still vague and even confused with the Bridge Information Model (BrIM). Therefore, this study provides a detailed review of 42 papers related to digital twins in bridge engineering, focusing on a proper definition, key features and creation techniques for bridge digital twin (BDT). The paper also compares BDT and BrIM from the perspectives of their elements, features, fidelity, services provided, and degree of development. The applications of BDT at different life cycle stages are identified, and the related technologies are analyzed in detail. The results show that the research clusters of BDT are divided into geometric model generation, finite element model updating, and management and are focused on the operation and maintenance phase while lacking attention in the design and construction phase. Besides, a reference framework of BDT based on the life cycle of bridges is proposed, and directions for future research are suggested.

Hui Yan, Yaning Wang, Yan Yan et al.

Wind loads can endanger the safety and stability of bridges, especially long-span cable-supported bridges. Therefore, it is important to evaluate the potential wind loads during the bridge design stage. Traditionally, wind load evaluation is performed by wind tunnel testing, which is relatively expensive. With the development of computational fluid dynamics and high-performance computing, numerical simulations are becoming more accessible for designers. However, the costs required for accurate numerical results are still high, especially for high-fidelity simulations. Under this condition, searching for a more efficient method to evaluate the wind loads in bridge wind engineering has become a new goal. It seems that flow visualization is a good entry point. Although flow visualization techniques have been developed in recent years, it remains difficult to extract velocity and pressure fields from images. To address this problem, physics-informed neural networks (PINNs) have been developed and validated. This study establishes a PINN to investigate the two-dimensional viscous incompressible fluid flow passing a generic bridge deck section. Two cases with different Reynolds numbers are tested. After careful training, it is found that the PINN can accurately extract the velocity and pressure fields from the concentration field and predict the drag and lift coefficients. The results demonstrate that PINNs are a promising method for extracting useful flow information from flow visualization data in engineering applications.