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Steel plate girders are susceptible to web buckling due to slender web. This phenomenon creates an undesirable failure mode and limits their ultimate load capacity. The use of fiber-reinforced polymer (FRP) composite materials offers a good prospect of strengthening the slender web of plate girders to avoid web buckling. This paper presents the details of experimental testing of steel plate girders with nonrigid end posts. These girders were tested in three-point bending. The end shear panels of the girders were strengthened by glass FRP (GFRP) pultruded section stiffeners or glass fiber fabric composite. GFRP stiffeners were applied either vertically or along the compression diagonal in the shear panel. All strengthened panels failed by web shear buckling associated with a breakdown of the employed strengthening scheme. It was found that the shear capacity of the panel remained unchanged by replacing the steel stiffener with GFRP stiffeners in the end panel. The critical buckling load of the strengthened panels increased up to 44% compared to the unstrengthened panel. The shear capacities of the panels strengthened by the glass fabric composite and diagonal GFRP pultruded section were the highest and similar to each other. Both these panels resisted a 50% larger shear compared to the unstrengthened panel. The positions of the plastic hinges in all tested panels were the same due to the same ratio of panel length and depth of the web. [ABSTRACT FROM AUTHOR]

To investigate the effects of a trapezoidal sleeper track (TST) on the vibration and noise of rail transit viaducts, the wheel–rail interaction model was first built according to the vehicle–track coupling dynamics theory. Subsequently, the vibration responses of the viaduct were analyzed using the beam–slab finite element method, and its radiated noise was calculated using the acoustic boundary element method. The modeling method was verified based on the test data of a 3 × 40 m continuous rigid frame bridge. Taking the Jialing River Bridge of Chongqing Rail Transit Line 9 as the background, the control effects of the TST on the vibration and noise of the viaduct and the effective laws of different track parameters on the bridge noise were analyzed. Results show that the simulated and measured values are in good agreement; for example, the modeling methods are reliable; the radiated noise of the viaduct is influenced by the vibration responses under the action of train load, which are jointly determined by dynamic wheel–rail force (external excitation) and displacement admittance (self-vibration characteristics); compared with embedded sleeper track (EST), the TST can reduce the overall vibration acceleration level and sound pressure level of the box girder web plate by 13.9 dB and 7.8 dB, respectively; the stiffness of the damping path is the primary factor influencing the noise of the elevated box girder, followed by the sleeper thickness and the fastener stiffness; taking the bottom plate as an example, the stiffness of the damping pad is reduced by 1 and the overall sound pressure level can be reduced by approximately 3 dB; the sleeper thickness is increased by 1, and the overall sound pressure level can be reduced by 1–2 dB; and the fastener stiffness is reduced by 1, and the noise reduction is within 1 dB. [ABSTRACT FROM AUTHOR]

This article discusses the use of digital methods, such as building information modeling (BIM) and structural health monitoring (SHM), in the maintenance management of a highway bridge in Germany. The goal is to combine these tools to create a comprehensive digital platform that organizes knowledge, incorporates real-time measurements, and provides feedback to the structural model and designer. The bridge is described in detail, including its dimensions and construction history. The monitoring system installed on the bridge measures various variables, including strain, vibration, inclination, displacement, temperature, and traffic loads. The article emphasizes the importance of a holistic understanding of the bridge's behavior and the need for collaboration between industry, academia, and federal institutions to address the challenges of digital bridge management. The authors express their willingness to share data and collaborate with others in the field. [Extracted from the article]

Plate girders are typically formed by the built-up of I-shaped plates. It is vulnerable and weak in resisting buckling. In this study, FE analysis models were developed to evaluate the flexural performance of a hybrid composite post-tension (HCPt) plate girder. The HCPt plate girder is made of double-web and in-fill concrete with pre-stressed tendon to prevent shear web buckling and improve flexural resistance. The sensitivity of design parameters to the performance of the girder was also investigated through a parametric study using four different configurations. The selected parameters are span length, steel grade, concrete grade, and level of pre-stressed force. The statistical analysis was performed using linear multiple regression model to predict the girder's flexural load and displacement. The results showed that web shear buckling was eliminated for models with in-fill concrete and pre-stressed tendon and failed by bending. Failure of the girder with double web was demonstrated by the combination of bending and web shear buckling. The concrete in-fill prevents the web plate from buckling and the beams generally fail in bending with high ductility. The load capacity of the hybrid composite plate girders with pre-stressing improved by 76% and 44% compared to conventional single-web plate girders and double-web plate girders, respectively. [ABSTRACT FROM AUTHOR]

The suspended monorail is a new mode of rail transit with light weight, medium speed and low cost. It has a lightweight and aesthetically pleasing structure but has obvious limitations when spanning obstacles such as rivers and valleys. From the perspective of structural force and operational safety, this paper puts forward a new composite beam structure scheme, in which track piers and track beams are erected on the main beam of a cable-stayed bridge, overcoming the limitations of conventional suspended monorail spanning ability. To investigate the complex force situation and the load transfer path at the junction of the main beam of the cable-stayed bridge and the track beam piers, finite element models of steel box girder section and concrete box girder section were established using ANSYS software. The results showed that, in the steel box girder section, the pier load was mainly transferred to the diaphragm and the middle web directly connected to it. Among them, the diaphragm load experienced relatively uniform stress, while the middle web's stress was mainly concentrated within a 2-meter radius centered around the pier, which could be mostly transferred to the steel girder bottom plate. 58% of the pier's axial force was transferred to the directly connected diaphragm. During the transfer of the pier column's transverse bending moment, 58. 8% of the shear force was transferred to the directly connected diaphragm. During the transfer of the pier column's longitudinal bending moment, 53. 4% of the shear force was transferred to the middle web. In the concrete box girder section, the pier load was mainly transferred to the concrete web and diaphragm directly connected to it. The concrete stress was mainly concentrated within a 2-meter radius centered around the joint surface, and the pier load was basically transferred within about 0. 5 meters below the joint surface. 68. 8% of the pier's axial force was transferred to the directly connected diaphragm. During the transfer of the pier column's transverse bending moment, 86. 4% of shear force was transferred to the directly connected diaphragm. During the transfer of pier column's longitudinal bending moment, 44. 6% of shear force was transferred to the middle web. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Architecture & Civil Engineering is the property of Chang'an Daxue Zazhishe and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Steel bridge designers and erectors primarily rely on approximate methods, such as 1D line girder analyses and 2D grid analyses. For curved or skewed bridges, this can give erroneous indications of the structure's true behaviour. Refined methods of analysis, such as 3D shell modelling, aim to bring a significant change in the practice of bridge engineering. By moving the industry away from simplistic design assumptions, refined analysis methods lead to more accurate, less conservative results, which in turn brings true benefits such as improved structural safety and increased economy. In this paper, several case studies on curved plate girder and tub girder bridges are presented, which cover the full bridge life cycle, from erection of the steel structure and placement of the concrete deck, down to live load analyses using influence surfaces and load rating. The case studies will be modelled with mBrace3D, a dedicated FEA software for curved steel bridges. [ABSTRACT FROM AUTHOR]

Effective width, as presented in Eurocode 3 is analysed. Efforts have been made to distinguish between the behaviour of the various structural parts acting as wide flanges. Different mechanical models are adopted: for the bridge deck plate between girders, for the cantilever deck part, and for the bottom plate of box girders with the presumption to reflect more adequately their actual participation in the complex girder work at bending. Also, the interaction between girders in a superstructure at loading is simulated as far as possible in order to replace to some extent a sophisticated spatial analysis. The Eurocode 3 way of presenting the matter is preserved. The results obtained are compared with the corresponding Eurocode parts and an assessment on the reported differences is given. The goal is to supply the designers with extended understanding the effects arising from the shear lag phenomenon. [ABSTRACT FROM AUTHOR]

Damage identification, both in terms of size and location, in bridges is important for timely maintenance and to avoid any catastrophic failure. An earlier experimental study showed that damage in a steel box girder orthotropic plate can be successfully detected using the measured vibration acceleration data. In this study, the wavelet packet decomposition (WPD) method is used to analyze the measured vibration acceleration responses and then the estimation of the permutation entropy (PE) on the re-constructed signals. A damage index is then defined based on the permutation entropy difference (PED) between the damaged and the healthy conditions to detect the location and size of the damage. The method is further validated through the finite element (FE) model of a steel box girder and the computed vibration acceleration responses when subjected to the sinusoidal excitations at different frequencies. In addition, the robustness of the methodology under different white noise interference conditions is also verified. The results show that the proposed methodology can effectively identify the location of human-made damage and accurately estimate the degree of damage under different frequencies of sinusoidal excitation. The method has shown a strong anti-noise property. [ABSTRACT FROM AUTHOR]

Lateral torsional buckling reduces the moment capacity of steel I-girders. To redress this weakening, one approach is to replace the conventional plate flange with a rectangular tube, which has higher lateral stiffness and is thus helpful to resist lateral buckling. At the same time, web openings are introduced to enable services to pass through, but this causes a reduction in strength. Girders with tubular flange plus web openings have not yet been discussed in the literature. In this paper, finite-element method modelling is used to fill this gap, studying different slenderness classifications, as well as parameters such as size of web openings, spacing and location. The results for a solid web are found to be more comparable to the Eurocodes for steel structures than the American Institute of Steel Construction codes, enabling good prediction of the flexural capacity. By introducing web openings, the flexural capacity is reduced by 10–20%, closer to the higher side for openings with large diameters located near the compression flange. Openings with an oval shape have less reduction in strength, whereas the square is unfavourable. Tubular flange girders, even if perforated, provide flexural strength enhancement and a considerable reduction in material compared with plate flange girders. This section also behaves better in relation to carbon dioxide emissions. [ABSTRACT FROM AUTHOR]

The dynamic response of a railway bridge depends on several parameters; the primary parameter is the fundamental natural frequency of vibration of the bridge itself. It is considered a critical parameter of the bridge as the driving or the forcing frequencies arising from moving trains may coincide with the fundamental frequency of the bridge and initiate a resonant response amplifying the bridge load effects. This condition may adversely affect the stresses experienced on bridge members and, consequently, the remaining fatigue life of the structure. Because the train adds additional time-varying mass to the bridge, this introduces a time-varying change in the bridge's fundamental natural frequency of vibration. As a result, train critical speeds will have a certain range depending on the train configuration. This article presents a simplified method using a power-law relationship to predict the frequency characteristics of a bridge as a function of the train-to-bridge mass ratio. The method is presented in a generalized form, which enables the frequency characteristics to be determined for any given combination of trains and simply supported bridges of short to medium span typically found on the UK rail network. The method is then demonstrated in a case study of a single-span, simply supported plate girder bridge. By considering the BS-5400 train traffic types, the proposed method is used to calculate bridge frequency effects, dynamic amplification, and train critical speed bandwidth for each train type. The simplicity of the proposed method, as it does not require any complex computational modeling, makes it an ideal and effective tool for the practicing engineer to carry out a quick and economical assessment of a bridge for any given train configuration. [ABSTRACT FROM AUTHOR]

Steel plate girders have been employed as structural bridge parts since the 19th century. They are typically made up of built-up sections in the shape of I-beams. Web and flange plates withstand shear force and bending moment, respectively. However, plate girders are vulnerable to shear buckling. Shear buckling resistance is increased by adding reinforced vertical stiffeners and, in some cases, longitudinal stiffeners. Nevertheless, these stiffeners are sometimes not enough to prevent extreme shear buckling and only delay the shear buckling of slender web panels. This study investigated a hybrid composite post-tension (HCPt) plate girder by experiment and finite element (FE) analysis. The structural performance of the HCPt plate girder was tested using three specimens: a double-web plate girder, an in-fill concrete double-web plate girder and an in-fill concrete double-web plate girder with prestress. Results showed that the steel web filled with concrete presented preferable strength and behaviour to the hollow steel web because of the concrete in-fill. It had high load capacity, strength and ductility. The concrete in-fill prevented the steel web plate from buckling, and beams generally failed in a ductile manner. Applying prestressing techniques reduced deflection under external loads, increased the load-carrying capacity and enhanced its flexural behaviour by 126% compared to the double web plate girder. The failure mode was changed from web shear buckling in a double web girder to bending in a hybrid composite plate girder, with an improvement of web shear buckling by 88%. The FE analysis result showed excellent consistency with the experimental result. [ABSTRACT FROM AUTHOR]

This paper presents a study on the explosion protection of prestressed concrete box girder, which is a commonly used in concrete bridges. The explosion protection tests of four prestressed box beams were designed with 1:5 scale. In order to evaluate the explosion performance of different protective layers, steel plate, ultra‐high‐performance concrete (UHPC) layer, and composite protective layer were used to protect the box girder. The experimental results revealed that under the effect of deck explosion, local penetrating failure occurred in the top plate of the box girder, which exhibited characteristics of punching failure. The web and bottom plate of the box girder as a whole exhibited bending characteristic. Compared with the unprotected box girder, the damage of the top plate of the protected box girder was less severe, whereas the damage of the bottom plate was greater. In working conditions 2–4, the UHPC protective box girder suffered less damage to the top plate, whereas the other protective box girders suffered more. The explosion dynamic responses of the box girder were compared, and the influences of different protective layers on the explosion dynamic response of box girder were studied. Based on the box girder damage, the protective efficiency of each protective layer under near‐explosion was studied. Based on the explosion tests, three‐dimensional numerical analysis model of box girder explosion was established. The accuracy of the numerical simulations of the box girder explosion were verified by comparing with the experimental failure data. Through the numerical results, the explosive energy dissipation capacity of different protective materials was compared and analyzed. Finally, based on the dynamic response of the box girder under different working conditions, the sensitivity of the protective layer to the dynamic responses of the box girder were studied. The analysis showed that the UHPC layer was sensitive to the change of prestress and explosion damage area of the box girder but had little influence on the rebars stress and the overall response of the box girder. [ABSTRACT FROM AUTHOR]

This study evaluates the mechanical performance of composite girders with corrugated steel webs via finite element modeling in ABAQUS. Utilizing corrugated steel webs enhances structural efficiency and material economy. The research delves into shear-bending interactions, analyzing load capacity, deflection trends, and failure mechanisms. ABAQUS simulations provide insights for design optimization of these girders in engineering contexts. The findings advance understanding of composite girders with corrugated webs, fostering more effective and sustainable construction practices. The investigation focuses on using corrugated plates to bolster the shear zones in plate girders. theoretical analyses of girders with corrugated web plates demonstrate their shear zone reinforcement capabilities. Different thickness of trapezoidal corrugated steel webs in girder specimens (4, 8, 12, 16, 20 and 24 mm) underwent two-point load testing to study the corrugation's interaction with the girders. Trapezoidal patterned corrugated web specimens against one control beam shows corrugation's significant impact on girder stability, enhancing ultimate load capacity and delaying buckling. A numerical analysis using confirmed the corrugated web's role in increasing buckling resistance. [ABSTRACT FROM AUTHOR]

The mountain area is faced with complex coJdjtions sucn as vertical and horizontal valleys, complex geologd topography, Vmny earthquake fault zones, high seismic intensityfriBk ecologyBkcriangeable climate. The traditional concrete bridgee heavy weilrhigh consumption of sand and gravel materials, large structural dimensions of steel box composite bridges, high steel consumption, and poor overall horizontal performance of steel plate composite beams, which are not suitable for mountain construction conditions. Thejefore, based onthe construction environment and application requirements of highway bridges in mountainous areas, the structural scheme of steeHX-steel pete composite beam is put forward in this paper, and the design 50 m landaTa-span steel box-steel plate composite beam is studied. Jrfl®iesu[ts show that the steel box-steel plate composite beam structure scheme is adopted, which has excellent mechanical characteristics of steel box girder and k simple structure of steel plate girder. It has the mechanical characteristics of balancidtransverse force and excellent longitudinal force", so it is a reasonable choice for small radius curved beam bridge in a mountainous area, so it is a reasonable choice for small radius curved beam bridge in a mountainous area. The steel box-steel plate composite beam adopts the integrated technology of manufacture, transportation and installation, which can better meet the road transport conditions in the mountain area. The longitudinal assembly of the manufacturing unit as the installation unit can ensure the rapid and high-precision installation of the construction site, and the assembly construction of the bridge in the mountain area has been realized. The technical and economic comparison shows that the mechanical performance of steel box-steel plate composite beam is similar to that of steel box beam and obviously better than that of steel plate girder. The steel consumption and construction period of steel box- steel plate composite beam are similar to that of steel plate girder, and are significantly less than that of the steel box girder. Therefore, the steel box- steel plate composite beam is a good choice for mountain bridge construction. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the reasonable flexural functions of ultra-wide box girders, reveal the mechanism of the shear lag effect, and improve the analysis theory of ultra-wide box girders. Considering a single-box three-chamber thin-walled box girder as an example, starting from an uneven transfer of shear flow, the flexural displacement function of the curved box girder under the influence of shear deformation of each plate was derived according to the flexural theory of a thin-walled box girder, balance equation of a thin-walled microelement plate, and theory of plane stress. The energy variational method was used to analyze the flexural displacement function, providing a theoretical solution for the shear lag effect of the curved box girder. A displacement correction of the cantilever plate displacement function was performed by comparing the calculation results for the shear lag coefficients. The results indicated that under the shear deformation of each plate, the flexural displacement functions of the wing and web plates of the box girder no longer satisfy the assumption of plane section. The flexural displacement function is a quadratic function of the transverse wing plate, and the web height is the sum of the first- and third-order functions. The theoretical calculation results agree sufficiently well with the experimental results, proving that the flexural displacement function of the box girder under the influence of the shear deformation of each plate is reliable. [ABSTRACT FROM AUTHOR]

This study solves the following tasks: a comparative analysis of theoretical, computer, and experimental data on the bending of experimental beams is given, the influence of various forms of reinforcement on the strength and stability of beams with a corrugated web is determined; the deformability of a beam with a corrugated web with perforations and without perforations in the elastic and elastic-plastic stage is studied. Experimental studies of models have allowed establishing the main characteristics of the load-bearing capacity, the features of the loss of stability of shelves and corrugated webs with various methods of reinforcing perforations. The given test results showed the necessity and economic feasibility of the work carried out to identify the optimal ways of reinforcing perforations, to meet the requirements of technologists for passing equipment within the construction height of the beams, reducing the consumption of steel for their reinforcement and reducing the complexity of production. The conducted mathematical modeling, laboratory tests, and the performed dispersion analysis allow the study to draw conclusions about the effectiveness of the improved BGS-3 and BGS-5 models and about the need to develop recommendations for introducing two proposed options for reinforcing the perforations of the BGS-3 and BGS-5 models. [ABSTRACT FROM AUTHOR]

I-section girders with different types of steel in the flanges and web (fyf > fyw, respectively) are known as transverse hybrid girders. These have proven to be more economical than their homogeneous counterparts. However, the use of hybrid configurations in the longitudinal direction of the element has yet to be studied. This paper uses optimization techniques to explore the possibility of constructing transverse and longitudinally hybrid (TLH) steel girders. The optimization objective is to minimize the manufacturing cost, including seven activities besides the material cost. The geometrically double symmetric I-girder design subjected to a uniform transverse load is performed using Eurocode 3 specifications. Nine case studies are implemented, varying the element span (L) and the applied load. The results show that establishing various configurations along the length of the element is beneficial. The optimum number of transition points is six, meaning the girder will have four configurations, i.e., one central and three others symmetrically distributed toward each half of the element. The optimum position for the first transition would be at 0.24 ∗ (L/2), the second at 0.40 ∗ (L/2), and the third at 0.60 ∗ (L/2). The optimum extreme configuration is usually homogeneous (fyf = fyw = 235 MPa). The others increase the steel quality in the plates, maintaining hybrid arrangements to reach the central one that usually remains with S700 steel for the flanges and S355 for the web. The study shows that TLH configurations are more effective for elements with larger spans. By applying the formulated design recommendations in a different case study, the manufacturing cost dropped by over 50% compared to the traditionally designed element and by more than 10% relative to the optimized element with a homogeneous configuration. The study's limitations and encouraging results suggest future lines of research in this area. [ABSTRACT FROM AUTHOR]

The shear capacity of steel beams is important for safe and efficient design in construction. Existing approaches have not accurately predicted the ultimate shear resistance of plate girders, but machine learning (ML) has emerged as a new technique to address this challenge. The Lazy Predict Python library automates the model selection and hyperparameter tuning process. In a recent study, up to 42 ML models based on Lazy Predict were applied to two datasets from 100 test results of varying specimens conducted by previous researchers. The XGB regressor model proposed in this study provided the highest performance, achieving an adjusted R squared of 0.9262 and 0.9417 R squared for the first dataset and an adjusted R squared of 0.9513 and 0.9692 R squared for the second dataset outperforming the other ML techniques in scikit-learn library. The values obtained from each test data were multiplied by the specimen's estimated shear capacity using a theoretical technique, and these were compared with experimental results. The maximum shear force resulting from the proposed modified equation was calculated using two standards, EC3 and AISC proposal, to estimate the ultimate shear force. This study demonstrates that ML techniques can improve predictions of shear capacity in steel beams, which is crucial for safe and efficient construction design. The recommended model exhibited an appropriate level of accuracy in calculating the shear capacity of steel beams based on test data from earlier research and the current study. The datasets and codes utilized in this study can be freely accessed at https://github.com/amrrashed/Shear-Capacity-of-Steel-Beams-with-Flat-Webs-by-Using-Optimised-Regression-Learner-Techniques. [ABSTRACT FROM AUTHOR]

Corrugated web girders with plate flanges have been widely applied in buildings and bridges due to the large shear capacity of the corrugated web (CW). However, experiments on corrugated web girders with tubular flanges are limited. Accordingly, this paper explores, through four full-scale small-size experimental tests used on buildings, the shear behavior of a type of girder formed with a CW, concrete-filled tubular flange, and bottom flat plate flange (CWGCFTF) with different CW thicknesses, wavelengths, and concrete strengths. Based on the imprecise results of one current test, a novel simple support device is proposed to improve the accuracy of the shear test of the CWGCFTF. The test results also show that the shear ratios of the tubular flange to the entire cross-section range from 15–18% when the loading reaches that of the corresponding shear stress to 80% of the shear yield strength of the CWs. Moreover, local buckling appears at the top surface of the steel tube with the CW shear buckling failure of the CWGCFTF under the shear tests. At the end, a theoretical equation of the shear ratio of the CW to the whole cross-section is derived, and a shear yield strength equation of the CWGCFTF is proposed and verified by comparisons with the test results. [ABSTRACT FROM AUTHOR]

The manufacturing process of steel plate girders generates residual stresses and geometrical imperfections in the flange and web plates that constitute them. These imperfections must respect the manufacturing tolerances that are presented in the regulation. In the present work several stages of the manufacturing process are studied, being these the thermal cutting of the plates, the assembling of the beam and the flange‐web welding process. This work is also accompanied by several results in terms of residual stresses and geometric imperfections of an experimental study and is made the confrontation of those results with the theoretical information available on the prEN 1993‐1‐14 and with the results obtained by numerical models that simulate the thermal processes of the plates cutting and welding. [ABSTRACT FROM AUTHOR]

The patch-loading resistance behaviors of Q690 high-strength steel (HSS) plate girders at elevated temperatures were investigated through a parametric study. The finite element (FE) simulation method was validated with 35 experimental results from the literature. The effects of elevated temperature, web width–height ratio, loading length, and web slenderness were investigated, where 512 FE models were included. A clear reduction in ultimate strength caused by the reduction in mechanical properties was observed with increasing temperature. The effect of elevated temperatures on the stress distribution on the web was negligible. The validation of design procedures in EN 1993-1-5 and AISC 360-16 was conducted, where the elevated temperature material properties of Q690 HSS were used. The results indicated that the current specifications were overly conservative to be used directly to predict the ultimate strength of the Q690 HSS plate girder at elevated temperatures. Accordingly, a design method based on EN 1993-1-5 was proposed. The formula in EN 1993-1-5 for determining the critical buckling factor was modified by introducing an amplification factor. The strength reduction function in EN 1993-1-5 was adjusted using the modified critical buckling factor. To determine the optimal undetermined constants in the strength reduction function, statistical calibration involving 400 combinations of 2 undetermined constants was performed for each pre-determined temperature. Two formulas with temperature as a variable were proposed to determine these undetermined constants directly. Based on the comparison, the accuracy of the proposed design method was better than those of the design methods in EN 1993-1-5 and AISC 360-16. [ABSTRACT FROM AUTHOR]

Web shear buckling of steel plate girders limits their load-carrying capacity in bending. Several analytical models have been suggested in the literature to estimate the shear capacity of plate girders. This paper presents a critical evaluation of several of these analytical models using the data of experimentally tested plate girders available in the literature. It was found that these analytical models make a conservative estimation of critical buckling strength for plate girders with larger slenderness and/or aspect ratios. Although the predicted ultimate shear strength varied across the different analytical models, no particular trend was identified to show that the aspect and/or slenderness ratios influenced the shear strength. A parametrically conducted analysis indicated that the threshold slenderness ratio (to cause buckling in the web panel) decreases with increasing yield strength and aspect ratio. The paper proposes simplified guidelines for the preliminary sizing of steel plate girders by avoiding shear buckling. It has been shown that the sizes of plate girders determined using the proposed guidelines satisfy design requirements for both flexure and shear. [ABSTRACT FROM AUTHOR]

The problem of vibration in urban rail transportation has become a current research hotspot. When a train passes through a bridge line at high speed, it interacts with the rail, leading to vibration energy transfer and causing issues such as vibration and noise in the line infrastructure. To propose a more targeted vibration-damping track structure, it is necessary to explore the vibration characteristics of urban rail transit bridge lines and understand the regulations governing the distribution of vibration energy. This paper employs the theory of vehicle–rail–bridge interaction to establish a coupled dynamics model for a subway A-type vehicle–integral ballast bed–box girder bridge. Based on the proposed model, the transmission characteristics and distribution of vibration energy in the rail–bridge system are systematically analyzed and the influence of the parameters of the track structural components on the power flow of the system are investigated. The results of this study indicate that low-frequency vibration energy in the track system of urban rail transit bridges is primarily concentrated within the track structure, whereas high-frequency vibration energy is mainly focused on the rail. The fastener, as a component connecting the rail and the overall roadbed, has different effects on the peak value of the power flow and the accumulation of vibration energy in various components such as the rail, the overall roadbed, the top plate of the box girder bridge, and the bottom plate in different frequency bands due to its own stiffness and damping. An appropriate increase in fastener damping is beneficial for reducing the accumulation of low-frequency vibration energy in the track structure. [ABSTRACT FROM AUTHOR]

Recently, the construction of composite steel plate girder bridges that uses precast concrete deck planks has significantly increased due to their ease of construction, rapid installment, relatively low cost, and lightweight. Recent structural failures have been reported for this type of bridge system, which include the total collapse of one section of the Mexico City Metro Overpass in May 2021. The bridge collapse killed 23 people, and dozens were injured. This study provides an overview of the causes of the failure of the Mexico City Metro Overpass. It highlights important structural deficiencies that are currently overlooked in design codes and could cause future catastrophic collapses in existing bridges that utilize the same type of bridge. Therefore, a detailed finite-element model of a composite steel girder bridge that uses precast deck planks was established. The bridge dimensions, properties, and loading conditions that were used in this study were obtained from the Mexico City Metro Overpass parameters with some modifications. The performance of the bridge structure was investigated under different conditions with consideration of joint deterioration between the precast concrete planks. The results indicated that the deterioration in the transverse joints due to long-term exposure to moisture, environmental conditions, and vibrations affected the amount of force that was transferred between the concrete deck and the bare steel girder and, therefore, hindered the composite action. The gradual loss of composite action could cause a significant increase in the demands that are imposed on the bare steel section and result in high deflections in the bridge deck. Further deterioration in the transverse joints could be ongoing due to the repetitive vehicle loading on the compromised composite girder. Vibrations and exposure of the cracked joints to moisture and weather could worsen these conditions. Catastrophic failure of the bridge could occur if the deterioration issues were not observed and addressed in a timely manner. This study concludes by providing recommendations for design considerations to improve bridge performance, extend service life, and prevent such failures. The collapse of the Mexico City Metro Overpass killed 23 people and injured many others and inspired this study. The system used in this bridge is a composite plate girder with full-depth precast concrete (FDPC) deck, a recent system that allows rapid construction. The best way for engineers to prevent repeating these accidents is to understand the factors that lead bridges to fail. This study starts by exploring the causes of failure in bridges when focusing on the expected deterioration effects in the long run. Simulation techniques are employed to build a model for a bridge that is similar to the system that collapsed in the Mexico City Metro Overpass. It was used to understand the factors that led to the collapse under the moving train load. The results showed that adhering to current design codes and guidelines is not sufficient to prevent the failure of a bridge. This is a serious issue, because the codes are expected to provide the minimum requirements that guarantee the safety of structures during their service life. Therefore, this study concludes by providing recommendations for design considerations to improve bridge performance, extend service life, and prevent such failures. [ABSTRACT FROM AUTHOR]

For steel structures service in corrosive environments, corrosion reduces the mechanical properties and effective thickness of the structural steel, which has a significant effect on the durability of steel structures. Titanium–clad bimetallic steel (TCBS), a bimetallic material composed of titanium alloy and carbon steel with excellent corrosion resistance has been suggested to solve the corrosion issue. The TCBS consisting of the TA1 titanium cladding and Q235 carbon steel substrate was introduced in the plate girder as the web to improve durability in this study. The stress–strain properties and failure performance of TCBS and Q235 carbon steel were discussed. Notably, the separation between the cladding and the substrate in the TCBS was observed during the necking stage in the tensile coupon test. Welding method between TCBS web and Q235 carbon steel flange was suggested for processing the plate girder, which was validated to be appropriate according to the experimental results. No crack in welding and TCBS web of plate girder was observed during the patch loading test. A numerical parametric study on the ultimate resistance of TCBS plate girder subjected to patch loading was conducted using the finite element software ABAQUS, in which three different key parameters were included. A comparison between the numerical and predicted results indicated that the design equations suggested in EN 1993–1–5 were too conservative to be directly used for predicting the ultimate resistance of the TCBS plate girder under patch loading, which was caused by the strain–hardening effect and yield plateau of the structural steel. The current design equations were modified to effectively predict the resistance properties of TCBS plate girders. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Harbin Institute of Technology. Social Sciences Edition / Haerbin Gongye Daxue Xuebao. Shehui Kexue Ban is the property of Harbin Institute of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aims to investigate the local elastic buckling behavior of simply-supported prismatic web plates under pure shear loading. Comprehensive finite element analysis is conducted to analyze the effects of various geometric parameters, such as tapering ratio, aspect ratio, and web slenderness, on the local elastic buckling behavior with simply-supported boundary conditions. An eigenvalue analysis is conducted to determine web plates' natural frequencies and corresponding shape modes with varying geometric parameters. Particular attention is given to the effect of the slenderness ratio, since current formulas do not consider the impact of the slenderness ratio on the elastic shear buckling coefficient. A sensitivity analysis is conducted to examine the importance of the web slenderness ratio for estimating the critical buckling coefficient of a prismatic plate under pure shear loading. Finally, a formula of the elastic local critical buckling coefficient for a simply-supported prismatic web considering the web slenderness effect is proposed, which can be used in international codes. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical performance of a polyester fiber concrete continuous rigid frame bridge during construction and the spatial stress distribution of the 0# block box girder, with a focus on the backdrop of the bridge in Pipa Zhou, Jiangxi Province. Stress monitoring at critical cross-sections during bridge construction was combined with FE simulations to analyze the stress and alignment deviation variations along the cantilevered construction process of the bridges. Subsequently, after validating the accuracy of the whole bridge model, the actual internal force of the box girder cross-section was extracted to act on the 0# block box girder solid model, and the spatial force of the 0# block box girder under the state of maximal cantilever and the completed bridge was further investigated. The results indicate that during cantilever construction, the top, and bottom plates of the box girder were subjected to compression, with the bottom plates having relatively low compression stress close to the critical values for compression and tension. Attention should be paid to controlling tensile stress application. After reaching a quarter of the bridge's span in construction, the alignment deviation of the main beam increases, necessitating enhanced monitoring and adjustments of the main beam elevation. Furthermore, FE analysis shows that under maximum cantilever and the completed bridge states, the stress variations of the top and bottom plates of the 0# block box girder remain consistent, with the top plate stress varying by no more than 2.5 MPa and the bottom plate stress varying by approximately 1 MPa. Moreover, the 0# block box girder shrinkage cracks were mainly located in the bottom and web plate, and the number of cracks in the 0# block box girder with polyester fibers was reduced compared to the cracks in the ordinary concrete box girder. [ABSTRACT FROM AUTHOR]

Corrugated steel flat plates have a number of benefits over conventional steel flat plates, including better buckling strength, a greater load capacity, a longer fatigue life, and cheaper construction costs. Corrugated plates have thus been used in a variety of civil engineering projects, including bridges, industrial structures, and steel coupling beams. To further enhance these properties, the web can be constructed as a core composed of two outside flat plates and a middle-corrugated panel. In this research, finite element software (ABAQUS 2017) was used to examine the effectiveness of steel plate girders containing various web types (flat plate, zigzagly corrugated plate, and core web with zigzagly corrugated panel). A large number of simply supported beam specimens were simulated and investigated under a three-point load in order to determine how the type of web affects the performance of girders under shear and flexural loadings. Three shear span-to-depth ratios (a/d) of 1.0, 1.83, and 2.5 were examined. Corrugation depth's impact on girder performance was also explored. The results of the study demonstrated that replacing flat plate web with corrugated plate having a zigzag shape improved the performance of the girders in regards to ultimate load and ductility. Additionally, when a core web was utilized, the performance of the girders was further improved. When compared to a steel girder with a flat web, the ultimate loads for girders with a core web and girders that only consisted of a corrugated plate web increased by 47% and 21%, respectively. [ABSTRACT FROM AUTHOR]

High‐strength steel materials (steel grades of S500 ‐ S960) gaining prominence in civil engineering, especially for large‐span bridges. In the case of bridges, the application of hybrid girders combining low‐ and high‐strength steel materials is an effective and economical solution. The hybrid girders generally consist of webs comprised of low‐strength steel and flanges made of high‐strength steel. In Europe, apart from some minor practical applications and research results in Sweden, these structure types are completely new solutions in bridges, and the theoretical background of their stability design is missing from the current European standardized design provisions. To determine the theoretical background of this girder type and to develop the design theories for application purposes it is essential to execute experimental laboratory test programs. Analyzing the local buckling and plastic behavior of hybrid steel plate girders through experiments is essential to have an approopriate knowledge on the geometrical and structural imperfections of the hybrid girders. Therefore, in the present paper the measurement of geometric imperfection on 14 welded hybrid steel box‐section girders with varying geometry is presented and their results are evaluated and discussed. The flanges of the examined hybrid girders are made of S700 or S500, the web of the specimens consists of S355 steel grade. The measured imperfection values are evaluated based on the steel grade and geometric parameters such as plate width or thickness. Using the measured imperfection, a numerical model will be developed to predict the bending and shear resistance of the specimens. [ABSTRACT FROM AUTHOR]

Steel plate girders with I‐section are frequently used in industrial buildings and bridge design as prismatic members that means as members with parallel flanges and rectangular webs. The structural efficiency can significantly be achieved if such members are designed with tapered webs that means with non‐rectangular webs. Depending on the flange inclination and the moment diagram, the stress in the webs of tapered plate girders is significantly affected also as known as Résal effect. Furthermore, the structural efficiency of plate girders can be improved if the flat webs are replaced by corrugated webs. The gain in out‐of‐plane stiffness due to the corrugated webs reduces the buckling sensitivity of the web. As tapered plate girders with sinusoidally corrugated webs under shear forces have not been subject of research up to now, a numerical investigation on the shear force resistance of such girders has been made. The most important findings are presented. It can be stated that the shear force resistance of tapered girders with corrugated webs cannot accurately be predicted by the existing calculation models for prismatic members. [ABSTRACT FROM AUTHOR]

Transverse stiffeners are used in steel plate girders with slender webs to provide lateral support to the web along the span and thus increase the plate girder shear resistance. Furthermore, transverse stiffeners anchor the tension field, resulting in axial compression in the stiffener. Despite this, it is widely assumed that the design axial force provided by the FprEN 1993‐1‐5 [1] for the transverse stiffeners is significantly greater than that observed in experimental testing and numerical simulations. The results of 550 nonlinear numerical simulations of plate girders loaded in shear up to failure are presented. Shear resistance and axial stiffener forces are evaluated while the effects of a wide parameter range as web aspect ratio and thickness, flange‐to‐web area ratio, and steel grade are investigated. The numerical results are compared to the European standard design values. Finally, a statistical analysis of the set of results is presented. The numerical analyses show that the axial forces installed in the intermediate transverse stiffeners are significantly lower than those specified by FprEN 1993‐1‐5 [1]. [ABSTRACT FROM AUTHOR]

Current offshore topside platforms are steel intensive structures, made of a variety of steel products such as plates, rolled beams, welded plate girders, and welded and seamless tubes. These structures are complex and generally designed using S355 steel grade mainly due to raw material availability, experience and knowledge when using this steel grade. In this study an optimisation of two offshore platforms is made by replacing the standard S355 steel with high strength steel in order to achieve a lightweight and optimised design with the same structural performance. The study has been carried out considering the full life cycle of an Oil&Gas topside platform and an Offshore substation topside, using as reference two topside structures built in the North Sea. Results indicate that for the same structural performance, by using high strength steel there is a reduction of the total weight which may reduce the overall life cost of the topside platforms, in particular fabrication and installation costs. [ABSTRACT FROM AUTHOR]

Longitudinal stiffeners are widely used in plated structures to prevent buckling of the slender plate elements and, therefore, to increase the load bearing capacity of these structures. There has been extensive research in the past regarding the shapes, sizes, and placement of these longitudinal stiffeners, however, there has been little research to make comparison between the different stiffener shapes across different numbers of stiffeners. The presented study compares the use of a single open stiffener, single closed stiffener, as well as the use of two open stiffeners. A numerical parametric study was conducted, considering different stiffener types, rigidities, and aspect ratios of the plates, for the cases of pure bending and compressions. The results of the study confirm that using a single closed stiffener or two open stiffeners is almost always more advantageous than the use of a single open stiffener. Furthermore, the study highlighted that it might be more advantageous to use two open stiffeners instead a single closed one. [ABSTRACT FROM AUTHOR]

Plate girders with I‐section frequently require large web openings to accommodate ducts and pipes in buildings and bridges. It is known that the critical load equivalent to an unperforated plate can be achieved by an appropriate reinforcement of the web opening. The majority of the investigations on thin‐walled webs with web opening under shear loading has been focused on web slendernesses ranging between 200 to 360. Three tests on plate girders with a web slenderness of 416 are presented that contain web openings. The effect of an all‐around reinforcement (hollow section) of the web opening is studied in three‐point bending tests. The tests are calculated with finite elements accounting for imperfections that had been measured before testing. A parametric study is performed to evaluate different types of reinforcements for high web slendernesses. [ABSTRACT FROM AUTHOR]

Assessment of the structural behaviour of steel and steel‐concrete composite plate girders exposed to web shear buckling is essential when it comes to their implementation involving heavy loads and/or long spans. In this paper, numerical model of a benchmark steel‐concrete composite girder capable of capturing this phenomenon has been developed using the ABAQUS software. The developed finite element model, based on a series of large‐scale girders planned to be tested in the future, has been evaluated and elaborated on. That includes the implementation of appropriate analysis procedures, element types and contact behaviour in the study of the post‐critical buckling behaviour of steel and steel‐concrete composite plate girders. The advantages and disadvantages as well as recommendations for the future use of the investigated modelling strategies have been scrutinized. In the end, this study demonstrates the parameters with the most significant influence on the structural behaviour of composite girders exposed to shear loading. [ABSTRACT FROM AUTHOR]

The corrosion of structural steel has a significant impact on the durability of plate girders servicing in marine environments. A high-performance configuration for a steel plate girder with a titanium–clad bimetallic steel (TCBS) web was suggested to eliminate the adverse effects of corrosion on the durability of bridges and industrial structures serving in corrosive environments. The patch-loading resistant experiment on the hybrid TCBS plate girder was innovatively conducted to clarify the feasibility of using TCBS in components with large deformation. Moreover, a numerical modeling method was suggested to research the patch-loading resistance response of hybrid TCBS plate girders. Based on the numerical analysis, a parametric study was performed to clarify the nonlinear bearing response of the hybrid TCBS plate girders subjected to patch loading, which included the effects of the stress–strain property of the structural steel, loading length, aspect ratio, and height-to-thickness ratio. Numerical results showed that current standards underestimated the ultimate bearing capacity of hybrid TCBS plate girders. Therefore, a suggestion for further improving the design methods of TCBS plate girders was recommended. Additionally, the research results of this paper yielded experimental evidence for the engineering application of bimetallic materials. [ABSTRACT FROM AUTHOR]

This research work presents the stress behavior of rib-deck weld joints in Orthotropic Steel Deck (OSD) railway bridges. It is essential to determine the most vulnerable load mode of the wheels for fatigue failure of OSD bridges and to improve the fatigue resistance of the welded rib-deck connection. Fatigue performance largely depends on the weld stress. Double-sided welds for rib-deck welds improve fatigue performance. The fatigue behavior of the rib-deck double-sided weld joint has been compared with the single-sided one. This study used Abaqus software to create the global shell model and the solid submodel of the OSD. The results of the structural stress-based finite element analysis indicated that when the center line of the front axle pair of a locomotive coincides with the center line of the midspan of the bridge, the most severe loading condition occurs. The rib near the main girder experiences the maximum structural stress in the weld toe of the rib-deck joint. Moreover, the rib-deck double-sided weld joints have 43.7% less structural stress compared to single-sided weld joints at the root of the weld, and this improves the performance during fatigue of OSDs. [ABSTRACT FROM AUTHOR]

High-stiffener-web combined opening girders used on passenger ships are prone to plastic hinge failures around the opening area and overall instability under combined and vertical loads, exhibiting complex buckling behaviors. In response to such situations, a series of numerical simulations and experiments on combined opening girders were conducted, considering several affecting factors such as opening shapes, initial crack defects, strengthening measures and stiffener web dimensions. On the basis of the verification of the reliability of the numerical method, the load-bearing characteristics of the combined open plate girders were investigated. It is concluded that the lumbar round opening can lead to localized plastic hinge failure phenomena, complicating the buckling behavior. In contrast, the inclusion of stiffeners can significantly improve the load-bearing capacity after the point at which instability occurs in the original specimen. In addition, detailed relationships between deformation trends and external loads are illustrated, which can be used as a reference for the optimal design of combined opening plate girders in actual ship structures. [ABSTRACT FROM AUTHOR]

This study aims to provide an effective method to study the behavior of a steel–concrete composite deck. First, the structural characteristics of the composite deck and the challenges arising in the computational analysis of the structure using general software are described. Then, an LPGE element that combines the plate element and the girder element into one element to conveniently construct the model with high computation efficiency is proposed. Based on the principle of multivariate field function, the constraint matrix for the plate and girder and the stiffness matrix for the LPGE are derived. The LPGE method is used to study the behavior of the composite deck through the computation of a steel truss arch bridge. The computation results are compared with the results obtained in ANSYS and the test results to verify the correctness and effectiveness of the LPGE method. The results of the paper offer references for the analysis of steel–concrete composite decks. [ABSTRACT FROM AUTHOR]