Abstract: This paper proposes a novel fully prefabricated composite deck system to achieve green and accelerated construction in bridge engineering. Ultra-high-performance concrete (UHPC), which has ...

Abstract: Ground-penetrating radar (GPR) is one of the most commonly used technologies for condition assessment of concrete bridge decks. However, there have been no fully automated algorithms to visualize the data collected with this technique. In such context, the current paper presents a method for a full automation of GPR data visualization and analysis. Based on the background removal, depth correction, synthetic aperture focusing technique (SAFT), and interpolation algorithms, this automated method produces a plan view map of amplitude of GPR signals. In the obtained map, two types of information are observed at the same time. First, as the strongest reflectors of electromagnetic energy, rebars will appear as the most visible. Second, the areas of corrosive environment and, thus, likely corrosion, will be detected as having low amplitude rebar reflections. As a proof of concept, the proposed method was implemented for two bare concrete bridge decks and two concrete bridge decks with asphalt overlays. In all cases, the results obtained were excellent where the maps pinpointed the areas affected by corrosion. These areas were confirmed by other methods of evaluation, such as electrical resistivity (ER), half-cell potential (HCP), chloride analysis of core samples, or visual inspection. With the demonstrated performance, the proposed method is expected to be an excellent alternative to the available methods of GPR data evaluation and visualization. In the future, it should be improved to provide an indication of corrosion severity/probability at each deck location.

Abstract: Marine plastics pollution (MPP) is an alarming problem affecting many countries, particularly in the Asia-Pacific region, and generated mostly from land-based sources. Five Asian countries (i.e. China, Indonesia, the Philippines, Vietnam and Sri Lanka) have been identified as the largest sources of MPP globally. This article presents two cases studies focused on the two largest polluters: China and Indonesia. Both countries face similar challenges in dealing with plastic pollution. They have weak legal and institutional frameworks in place to deal with MPP. The two case studies also show that there have been more creative and effective measures taken at the domestic level by local governments and non-state actors, many of which involve partnerships among different stakeholders. This article argues that governance efforts to address MPP require an ‘all hands-on deck’ approach, involving multi-level and multi-actor strategies and targeted regulatory and non-regulatory measures. However, our findings also suggest that most efforts should be directed at the subnational level, from which the problem mainly originates. This article proposes a number of legal and policy recommendations, based on the lessons learned from the case studies, which can be instrumental in reducing the global MPP crisis.

Abstract: Steel and steel-concrete composite girders are two types of girders commonly used for long-span bridges. However, practice has shown that the two types of girders have some drawbacks. For steel girders, the orthotropic steel deck (OSD) is vulnerable to fatigue cracking and the asphalt overlay is susceptible to damage such as rutting and pot holes. While for steel-concrete composite girders, the concrete deck is generally thick and heavy, and the deck is prone to cracking because of its low tensile strength and high creep. Thus, to improve the serviceability and durability of girders for long-span bridges, three new types of steel-UHPC lightweight composite bridge girders are proposed, where UHPC denotes ultra-high performance concrete. The first two types consist of an OSD and a thin UHPC layer while the third type consists of a steel beam and a UHPC waffle deck. Due to excellent mechanical behaviors and impressive durability of UHPC, the steel-UHPC composite girders have the advantages of light weight, high strength, low creep coefficient, low risk of cracking, and excellent durability, making them competitive alternatives for long-span bridges. To date, the proposed steel-UHPC composite girders have been applied to 14 real bridges in China. It is expected that the application of the new steel-UHPC composite girders on long-span bridges will have a promising future.

Abstract: We have modeled the dynamic loading of a semi-wagon body when it is fixed by a viscous coupling relative to the deck of a railroad ferry. The relevance of this research relates to the fact that the movement of wagons by sea on railroad ferries is accompanied by the effect of significant magnitudes of loads on the load-bearing structures of their bodies. The numerical values of these loads are significantly higher than those that act on a wagon under operation along a railroad. In addition, the current scheme does not ensure the reliability of Fastening the body and thus causes damage to its structural elements. This necessitates conducting unplanned repairs of wagons that are transported on railroad ferries. It is therefore proposed to improve the scheme of fixing a wagon relative to the deck of a railroad ferry. In order to mitigate the effect of loads exerted by chain couplers on a wagon body, it is suggested that they should be connected by a flexible link, rather than rigid, by installing a specialized device ‒ a damper between a body and a deck.To simulate the dynamic loading of a wagon body taking into consideration the proposed technical solutions, a mathematical model has been constructed and the magnitudes of accelerations acting on the body have been determined. The model accounts for the movement of a railroad ferry with wagons under side rocking motion as one of the main types of vessel fluctuations. It was established that it becomes possible, by taking into consideration the proposed scheme of fixing a wagon body relative to the deck, to reduce the magnitude of its dynamic loading by 30 %.We have also determined the dynamic loading on a wagon body by computer simulation in the programming environment CosmosWorks. Numerical values and the fields of deployment of semi-wagon body's accelerations have been determined. The constructed models were verified based on an F-criterion. The present research will contribute to maintaining the bearing structures of wagons' bodies when they are transported on railroad ferries, as well as improving the efficiency of their operation along International transport corridors

Abstract: The objective of the research described in the paper was the structural development of a FRP composite bridge deck intended for manufacturing and application in road bridges in Poland, mainly for redecking the deteriorated bridge slabs. The appropriate shape of the sandwich bridge deck panel, its overall structure, constituent materials and the associated cost-effective manufacturing technology were determined following a comprehensive analysis of the similar solutions recently developed worldwide. In the first stage three different small-scale deck panel prototypes were designed and fabricated, assuming the various core configuration of the sandwich structure. Based on manufacturing tests and initial static tests the feasibility and stiffness of all prototypes were assessed to select the optimal deck solution in terms of material, structure and technology. In the second stage of the research a full-size 2.0 × 5.0 m bridge deck panel was designed taking into account the bridge loading according to Eurocode 1. The full-size bridge deck prototype was subjected to a series of static load tests simulating the relevant load. The tests confirmed the appropriate stiffness and load carrying capacity of the novel FRP bridge deck panel, quite similar to performance characteristics of other FRP bridge decks implemented worldwide. However, the necessary technological and research works on the novel sandwich bridge deck panel in order to increase its safety level were also outlined.

Abstract: Concerns about harmful exhaust emissions from ships have been an issue. Specifically, the emissions at ports are the most serious. This paper introduces a hybrid power system that combines conventional diesel generators with two different energy storage systems (ESSs) (lithium-ion batteries (LIB) and supercapacitors (SC)) focused on port operations of ships. To verify the proposed system, a bulk carrier with four deck cranes is selected as a target ship, and each size (capacity) of LIB and SC is determined based on assumed power demands. The determined sizes are proven to be sufficient for a target ship through simulation results. Lastly, the proposed system is compared to a conventional one in terms of the environmental and economic aspects. The results show that the proposed system can reduce emissions (CO2, SOX, and NOx) substantially and has a short payback period, particularly for ships that have a long cargo handling time or visit many ports with a short-term sailing time. Therefore, the proposed system could be an eco-friendly and economical solution for bulk carriers for emission problems at ports.

Abstract: The slippage damage caused by weak interlaminar bonding between cement concrete deck and asphalt surface is a serious issue for bridge pavement. In order to evaluate the interlaminar bonding of cement concrete bridge deck and phosphorous slag (PS) asphalt pavement, the shear resistance properties of the bonding layer structure were studied through direct shear tests. The impact of PS as a substitute of asphalt mixture aggregate, interface characteristics, normal pressure, waterproof and cohesive layer types, temperature and shear rate on the interlaminar bonding properties were analyzed. The test results indicated that the interlaminar bonding of bridge deck pavement is improved after asphalt mixture fine aggregate was substituted with PS and PS powder, and the result indicated that the shear strength of grooved and aggregate-exposed interfaces is significantly higher than untreated interface, the PS micro-powder or anti-stripping agent can also improve the adhesion between layers when mixed into SBS asphalt. This study provided important theoretical and practical guidance for improving the shear stability of bridge deck pavement.

Abstract: Coastal bridge damage has become a severe issue of concern in the recent past with the destruction of a considerable number of bridges under the impact of waves during tsunami and storm surges. These events have become more frequent, with waves reaching the bridge deck and causing upliftment and destruction. Past studies have demonstrated the establishment of various theoretical equations which works well for the submerged deck and regular wave types but show much scatter and uncertainty in case of a deck that is above still water level (SWL). The present study aims to generate a solitary wave to represent an extreme wave condition like a tsunami in the numerical wave tank modeled using the open source computational fluid dynamics (CFD) model REEF3D and to study the vertical impact force on the coastal bridge deck. A parametric study is carried out for increasing wave heights, girders spacing and depth for varying airgaps to analyze the effect of these parameters on the peak vertical impact force. It is observed that increasing the girder spacing and girder depth is effective in reducing the peak vertical impact force for the cases considered.

Abstract: To investigate the mechanism of base-metal cracking on diaphragm cutout in a self-anchored suspension bridge with orthotropic steel deck (OSD), multi-scale finite element models were established to...

Abstract: Orthotropic steel deck (OSD) bridges have gained increasing popularity around the world during the past 20 years. The steel deck pavement is one of the major components of an OSD bridge and a well-...