This paper addresses the lifecycle cost assessment of a steel girder bridge considering the material costs and maintenance activities along the bridge's lifecycle. A reference highway bridge case ...study is chosen. It was initially designed using carbon steel S355. Two more steel grades are included in the comparison: high strength carbon steel S460 and duplex stainless steel EN 1.4162. For each design option, fatigue appears to be the driving design criterion for the following critical welded details: transversal stiffeners, cope holes and full penetration butt welds in the flanges. In addition to ultimate limit state verifications, specific attention is therefore given to fatigue through the use of different verification methods: the well-known nominal stress method and the hot spot stress method. It is concluded that the net present value of the lifecycle cost of the stainless steel option is attractive compared to painted the carbon steel options.
•Comparative design of a highway girder bridge was performed.•Designs made of S460 and EN 1.4162 were compared to the initial design of S355.•Ultimate, serviceability and fatigue limit states are considered.•Life cycle cost assessments are carried out for each design.•The feasibility of each option is discussed.
Der sechsstreifige Ausbau der A3 zwischen dem AK Fürth/Erlangen und dem AK Biebelried führte zum Neubau eines Überführungsbauwerks ohne Mittelunterstützung mit 70 m lichter Weite. Als Ergebnis eines ...Realisierungswettbewerbs wurde ein integrales Bogenfachwerk als Auftaktbauwerk ausgewählt. Die innovative Verknüpfung von Bogen und Fachwerk führte zu einem sehr effizienten und robusten Tragwerk und einer äußerst flachen Überspannung der Autobahn. Bei der Planung wurden alle Aspekte der Nachhaltigkeit berücksichtigt – Wirtschaftlichkeit, Dauerhaftigkeit, Umweltverträglichkeit und Ästhetik. Innovative Details wie eine Bordsteinlinienentwässerung oder eine besondere Gestaltung der Untersicht mit gevouteten Fertigteilen führten zu einem Maximum an Funktionalität und Dauerhaftigkeit in Kombination mit guter Gestaltung. Für diesen Beitrag zur Formenvielfalt im heutigen Brückenbau erhielt das Bauwerk den Deutschen Ingenieurpreis Straße und Verkehr 2023 in der Kategorie Baukultur.Herrn Prof. Dr.-Ing. Thomas Ummenhofer zur Vollendung seines 60. Lebensjahres gewidmet
Abstract
In the trend of information technology, BIM Technology has been widely used in the design, construction and maintenance stages of bridge engineering activities with its own advantages. At ...present, BIM Technology has made further development to realize the bridge life cycle information. In view of the shortage of information carrier in the application of EBS in BIM life cycle, this paper proposes a 2-dimensional EBS coding system component decomposition coding system. The 2-D EBS coding system is composed of component information and subsidiary information. Through the practical application of Shapotou Yellow River Bridge in Ningxia, the possibility of 2-D EBS coding system in bridge life cycle information integration, exchange and storage is further verified. It provides a link role for bridge life cycle informatization, and has strong engineering practice significance.
•Effects of UHPC and stud diameters on shear behaviors of headed studs are studied.•Specimens with identical geometry showed different post-peak behaviors and large slip.•Existing formulae of shear ...capacity of headed studs are evaluated by data of collected 120 push-out specimens.•Formulae in existing codes overestimated the shear capacity of headed studs in UHPC.
Featuring high compressive and tensile strengths, ultra-high performance concrete (UHPC) is an efficient and durable alternative for conventional concrete in steel–concrete composite sections. However, few experimental studies to date have involved large diameter (≥ 25 mm) headed studs, UHPC with compressive strengths larger than 130 MPa, and relatively low strength but cost-effective UHPC. This study investigates the shear performance of steel headed studs embedded in UHPC through pushout tests with 24 specimens. Specimens included headed studs with diameters of 16 mm, 19 mm, 22 mm, and 25 mm, and either UHPC with compressive strength of 152.5 MPa or a cost-effective UHPC with a strength of 85.7 MPa (named as HPC hereafter). The results showed that smaller-diameter specimens (16 or 19 mm) failed with stud shank fracture, while the larger-diameter specimens (22 or 25 mm) failed at welding lines. Compared to HPC, UHPC did not notably increase the performance of headed shear strength. The load response consisted of a linear stage, a softening stage, and a post-peak stage lasting up to a slip of 10 mm or greater, with high variability in post-peak response among specimens with identical parameters. A global database of 120 push-out test specimens from this study and references was established, covering concrete strengths from 23.5 MPa to 152 MPa. The formulae given by AASHTO LRFD Bridge Design Specification, Eurocode-4, and Chinese code GB50017-2003 overestimated the shear capacity of headed studs by 52 %, 5 % and 53 %, respectively. The equation for the slip modulus slightly overestimated the slip modulus of headed studs. In conclusion, this study broadened the ranges of concrete strength and diameter of headed shear studs, and revealed that the existing equations of predicting shear capacity and slip modulus need improvement.
Abstract Investigations of extreme buffeting responses on long-span bridges suggest revisiting the current design guidelines as these might be non-conservative. For such purposes, the full long-term ...analysis is the most accurate methodology. Despite its well-known advantages, the method is not the standard practice in bridge design, mainly due its high computational demand. Recent studies have contributed to make the analysis feasible by employing enhancing strate-gies such as machine learning and efficient simulation techniques. The results are promising, and the computational effort can be reduced to a fraction of the original formulation. It’s necessary that the more accurate long-term methods are included in the design guidelines for long-span bridges. In the Norwegian Handbook for bridge design, only a simplified methodology is recommended, which exposes a gap between research and engineering practice that must be fulfilled. Therefore, this paper presents a set of recommendations for implementing the full long-term analysis based on our experience with the calculations from the Sulafjord bridge, a 2800m single span suspension bridge currently in design and feasibility stage. The objective is to provide recommendations to back-up the abovementioned regulating effort and contribute to close the gap between academia and engineering practice.
•Different failure modes were observed depending on the presence of reinforcement.•Better structural performance can be obtained for specimen with UHPC slab.•Grooved joint improves the interface ...shear capacity of UHPC specimens.•A shear strength equation for UHPC-substrate construction joint is proposed.
As an advanced cement-based composite material, ultra-high - performance concrete (UHPC) has been widely used in bridge engineering due to its superior mechanical properties and durability. One of the most efficient bridge structures consists of composite beams with precast UHPC girders and cast-in-place concrete slabs. There is limited knowledge, however, about the shear behaviour of UHPC-substrate construction joints. In order to address this issue, this study is carried out to examine the shear-friction behaviour of joints between precast UHPC girders and cast-in-place concrete slabs by means of push-off tests, varying slab type, shear reinforcement ratios and interface treatments. Experimental analysis indicates that reinforcements across the joints could significantly improve the ultimate shear resistance of an interface to a UHPC substrate with a groovedsurface. Additionally, the shear stress of the interface is also affected by the cast-in-place slab type. The surface treatment of the grooved surface was also found to be an efficient method for improving the shear capacity of an interface between a precast UHPC girder and a cast-in-place concrete slab. Finally, to predict the interfacial shear strength between precast UHPC girders and cast-in - place concrete slabs, a more precise equation, based on the AFGC 2013 design guideline, was proposed and validated by experimental results presented in this paper and beyond. The proposed design equation could lead to safer and more reliable design of such type of bridge joints.
•Kriging model is used to accelerate the heuristic optimization.•A continuous box-girder pedestrian bridge with a low embodied energy is sought.•Kriging obtains a coefficient of variance of 3.67% ...improving the conventional method.•Kriging with N = 50 increases the optimum energy by 2.54%•Kriging shows a reduction in the computational cost of the 99.06%
Structural optimization is normally carried out by means of conventional heuristic optimization due to the complexity of the structural problems. However, the conventional heuristic optimization still consumes a large amount of time. The use of metamodels helps to reduce the computational cost of the optimization and, along these lines, kriging-based heuristic optimization is presented as an alternative to carry out an accelerated optimization of complex problems. In this work, conventional heuristic optimization and kriging-based heuristic optimization will be applied to reach the optimal solution of a continuous box-girder pedestrian bridge of three spans with a low embodied energy. For this purpose, different penalizations and different initial sample sizes will be studied and compared. This work shows that kriging-based heuristic optimization provides results close to those of conventional heuristic optimization using less time. For the sample size of 50, the best solution differs about 2.54% compared to the conventional heuristic optimization, and reduces the computational cost by 99.06%. Therefore, the use of a kriging model in structural design problems offers a new means of solving certain structural problems that require a very high computational cost and reduces the difficulty of other problems.
•Performance-based design framework of bridge structures under vehicle-induced fire accidents is presented.•Fire-resistance levels and relative evaluation standards for different fire scenarios are ...defined.•Risk analysis-based maintenance cost calculation method of bridge fires is established.•A typical case study for performance-based design of bridge structures under vehicle-induced fire accidents is carried out.
Although structural robustness under different fire scenarios has been widely studied in numerous engineering projects, performance-based method still needs to be further defined for better design of bridge structures under fire accidents. This paper presents a practical framework for the performance-based design of bridge structures under vehicle-induced fires. Fire scenarios, structural-thermal analysis method, fire-resistance levels, and a risk analysis-based maintenance cost evaluation process are all defined in detail. The applicability and rationality of this design process are illustrated through a typical case study. The results of the case study demonstrate that the initial properties of the bridge structure can satisfy the defined fire-resistance levels properly, while additional measures for decreasing the burning time are still needed to limit the fire maintenance cost in an acceptable level. The proposed performance-based design process can be widely used in engineering practice.
Abstract The integral bridge with steel-concrete composite girder will be affected by wind load in the natural environment, so the buffeting effect of wind on the integral bridge with steel-concrete ...composite girder cannot be ignored. In order to solve the above problems, the numerical simulation analysis on the wind load on integral bridge with steel-concrete composite girder based on cloud platform is carried out. Before the buffeting analysis of the bridge, the wind environment condition should be calculated. Taking the integral bridge with steel-concrete composite girder as an example, based on empirical formula, the influence of girder size change on static wind load and static wind load under different wind speeds are calculated and analyzed. With the help of Davenport fluctuating wind’s power spectrum, the fluctuating wind field of integral bridge with steel-concrete composite girder under certain wind speed is simulated by harmonic synthesis method, the wind load value of integral bridge with steel-concrete composite girder is simulated, and the structural design of bridge is carried out, in order to ensure the scientificity and safety of bridge design. The numerical simulation can correctly react the test law, and can predict the wind resistance of the structure with the existing model.
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