bluuebunny/crossref_metadata_2025 huggingface dataset:
Author Characteristics for Major Accounting Journals: Differences among Similarities 1989–2009
Authors: Fogarty Timothy J. , Jonas Gregory A.
Published: May 2013

Many academic accountants have explicit or implicit motivations to publish their research in the best journals in the discipline. However, whether the chances of success are better at some of these journals is unknown. This paper examines the archival record to find differences within the authorship of three such publications (The Accounting Review, Journal of Accounting Research, Journal of Accounting and Economics) over a recently completed 20-year period. The journals do not differentiate according to the authors' doctoral training, but are differently sensitive to place of faculty employment. The journals are equally receptive to non-U.S. authors, but different in their receptivity to recently graduated and frequently appearing authors. Although areas of change over time are noted, both among journals and within each journal itself, the record also shows a good deal of consistency in other relationships over the 20-year period.
Thoracoabdominal Wall Defect with Complete Ectopia Cordis and Gastroschisis: A Case Report and Review of the Literature
Authors: Pepper Michael A. , Fishbein Gregory A. , Teitell Michael A.
Published: May 2013

Ventral wall defects are extremely rare anomalies that are likely caused by the failure of the ventral wall to close during week 4 of development. We report a case of severe thoracoabdominal wall defect including complete thoracic ectopia cordis and gastroschisis. This combination represents a novel constellation of findings in a single patient. This unique case further demonstrates an anatomically normal heart with age-appropriate development and an intact diaphragm. We review the literature of other reports and discussions of entities that share overlapping features with this case.
Laser scribing on HOPG for graphene stamp printing on silicon wafer
Authors: Butikova Jelena , Polyakov Boris , Dimitrocenko Lauris , Butanovs Edgars , Tale Ivars
Published: May 2013

Highly oriented pyrolytic graphite (HOPG) was scribed by pulsed laser beam to produce square patterns. Patterning of HOPG surface facilitates the detachment of graphene layers during contact printing. Direct HOPG-to-substrate and glue-assisted stamp printing of a few-layers graphene was compared. Printed graphene sheets were visualized by optical and scanning electron microscopy. The number of graphene layers was measured by atomic force microscopy. Glue-assisted stamp printing allows printing relatively large graphene sheets (40×40 μm) onto a silicon wafer. The presented method is easier to implement and is more flexible than the majority of existing ways of placing graphene sheets onto a substrate.
An unexpected position of the dialyses catheter during routine x-ray examination: a case of the double superior vena cava
Authors: Atalić Bruno , Sabo Goran , Toth Jurica
Published: May 2013

This paper presents a case of a 55 year old male patient, who after hospitalization at the Intensive Care Unit, due to acute renal failure, at first had a central venous catheter inserted through his right subclavian vein, and then a dialysis catheter inserted through his left subclavian vein. A routine X-ray examination confirmed that the central venous catheter was visualised in the expected position of the right atrium, which was reached via superior vena cava. The dialysis catheter was not visualised in the expected position of the right atrium, but in the surprising location of the left ventricle, with its line continuously passing by the left sternal edge instead of crossing the middle line in order to enter the superior vena cava, thus raising a concern over its misplacement and possible side-effects (abstract image photo). Due to the absence of pneumo- or haemato-thorax, as the most common signs of the venous rupture, the possible explanation was an anatomical variation. Dialysis catheter displacement in the left internal thoracic vein was proposed as another possibility. Literature research explained it as a case of double superior vena cava, which was confirmed by analysis of the computerised tomography pulmonary angiogram.
An all-fibre multi-parameter sensor for composite structures based on a chirped fibre Bragg grating
Authors: Zhan Y. , Li L. , Yang F. , Gu K. , Wu H. , Yu M.
Published: May 2013

An all-fibre multi-parameter sensor for composite structures based on a chirped optical fibre Bragg grating (CFBG) has been studied theoretically and experimentally. The principle of multi-parameters sensing with a single CFBG is based on that the centre wavelength and the FWHM (full width at half maximum) in the reflection spectrum of a CFBG vary linearly with the temperature and/or the axial stress. A wavelength matched optical fibre long period grating (LPG) and another wavelength matched reference CFBG (CFBGR) have been used to interrogate the signal of the sensor CFBG (CFBGS). The temperature and strain of the composite structure have been monitored real-time with one CFBG as a single sensor head. The temperature resolution of 0.12°C and the strain resolution of 1.1μɛ for a composite structure have been realized in experiments. The experiment results agree well with the theoretical analyses.
Upgrading Techniques for Quay Walls
Authors: Douairi Mohamed , de Gijt Jarit
Published: May 2013

The rapid expansion of trade has led to fast growth of handling of goods in many ports. The ports are the catalysts of development of trade and this will result in large future effects.

The increase of ship numbers and sizes will challenge ports in every aspect. Ports have to adapt to the upcoming changes by increasing capacity in every dimension.

Quay walls are one of the most essential components of port infrastructure and with growing volumes of cargo and increasing vessel sizes, the demand on these structures is increasing. Efficient transfer at the quay wall interface is required for the commercial and operational success of any terminal or port. This paper comprises many options for creating extra depth in front of quay walls. Not all presented options have been used in practice.
Load testing result analysis of the Latvian bridges
Authors: Paeglite Ilze , Paeglitis Ainers
Published: May 2013

The paper presents results obtained from the bridge dynamic load tests for a period of more than 50 years. The main values obtained from the load testing are - the vertical displacement of the deck including dynamic load factor, the natural frequency of the bridge, the dynamic increment and the logarithmic decrement. The obtained results show that the natural frequency depends highly on the length of the span, static scheme of the bridge, type of the span cross-section, structural materials, construction methods and bearing type. It was found that the dynamic increment did not depend on the natural frequency, but was dependent on the logarithmic decrement. The logarithmic decrement showed dependency on the length and the types of the span structures.
Rehabilitation strategies for steel and movable bridges in Rotterdam
Authors: Reusink Jaco , Heller René
Published: May 2013

Recently a new Dutch Design Code Series (NEN8700) has been issued, prescribing minimum reliability requirements for existing building structures according to Dutch law. First practical experiences with this codes have shown that especially for prewar and historic bridges it is nearly impossible to fulfil these minimum requirements in conjunction with Eurocode bridge design loading requirements, without executing elaborate strengthening programmes. However preliminary studies have indicated that a significant difference in traffic count and axle loading exists between urban traffic and highway traffic. This paper reflects project experiences of the last decades rehabilitation and replacement programmes of older urban movable steel bridges. The movable bascule Leuvebrug is the first Rotterdam bridge recalculated by the new NEN8700 code, as a result bridge replacement, earlier based on codes for new bridges, was no longer considered necessary.
Management of overweight vehicle traffic on road bridges
Authors: Zandonini Riccardo , Debiasi Emiliano , Zonta Daniele
Published: May 2013

Bridges in service in most Western Countries were built according to codes with design loads that are now inconsistent with today’s traffic demands. Currently, transportation agencies do not know how to respond to transit applications on their bridges. This contribution focuses on the legal issues entailed by overweight/oversize load permits issued by transportation agencies. Indeed, correct decision-making should consider the legal liabilities involved in possible catastrophic events. In this paper we illustrate how this problem is addressed by the Department of Transportation of the Italian Autonomous Province of Trento (APT), a medium-sized agency managing approximately one thousand bridges across its territory. In their basic approach, APT does not authorize movement of overweight loads unless it is demonstrated that their effect is less than that of the nominal design load. When this condition is not satisfied, a formal evaluation is carried out in an attempt to assess a higher load rating for the bridge. If, after the reassessment, the rating is still insufficient, the bridge is classified as sub-standard and a formal evaluation of the operational risk is performed to define a priority ranking for future reinforcement or replacement.
Influence of High Axial Tension on the Shear Strength of non-shear RC Beams
Authors: Joergensen Henrik B. , Hoang Linh C. , Fabrin Lars S. , Maagaard Joergen
Published: May 2013

This paper deals with the influence of high axial tension on the shear strength of beams without shear reinforcement. An experimental program with shear-tension tests was carried out. The experimental results have been used to evaluate the applicability of the Eurocode 2 (EC2) design formula in cases with large normal forces. In addition, the experiments have been used to evaluate an extension of the plasticity based Crack Sliding Model (CSM) to cover cases with large normal forces. The test results show, that even in the present of very high axial tensile stresses and strains, the member is still able to carry significant shear stresses. The analysis reveals that the EC2 formula is over conservative in this regard.
Concrete Slab Strengthening with CFRP Textile Reinforced Shotcrete
Authors: Zwicky Daia
Published: May 2013

This paper reports on a new strengthening system for concrete elements, being composed of carbon- fiber reinforced polymer fabrics (CFRP fabrics) embedded in shotcrete. The strengthening system was evaluated in a test series on full-scale single span slab strips of 6 m length, on a non-strengthened reference specimen and two slab strips with different strengthening ratios. The paper discusses the test results with regard to serviceability limit state (flexural stiffness, crack widths, and admissible loads for given deflection limits), and to ultimate limit state (strengthening ratio, behavior at rupture, post-peak bearing capacity, and ductility). It concludes with some analytical considerations on the structural behavior and bearing capacity of the new strengthening system.
Fibre-Reinforced Plastic (FRP) deck substitution of a fatigue damaged steel deck
Authors: Van Ijselmuijden Kees , Tromp Liesbeth
Published: May 2013

This paper presents three options to replace a fatigue damaged steel deck with an infusion Fibre Reinforced Polymer (FRP) deck. Current traffic loading is now heavier than in the 1970’s, so a deck sensitive to fatigue loading will be controlled by a more onerous loading regime. The project task is to replace the original damaged steel deck with a lighter deck and thereby relieve the main girders. The additional benefits of substituting the damaged steel deck is, that the original deck will not have to be repaired and also the FRP deck has lower stresses than the steel deck so therefore less fatigue sensitive.
Mechanical Behaviour of Laminated Carbon Fibre Grid with a Large Cross- sectional Area in New Strengthening Method
Authors: Miyauchi Katsuyuki , Shimoeda Hiroyuki , Kobayashi Akira
Published: May 2013

A new strengthening method of an existing bridge pier by using carbon fibre grid and polymer cement mortar was developed. Carbon fibre grid with a large cross-sectional area will be needed for a strengthening of an existing bridge pier. Therefore, in the strengthening by the new method, two or three layers of carbon fibre grid will be laminated. Accordingly, it is necessary to clarify the mechanical behaviour of both laminated plates of carbon fibre grid with a large cross-sectional area and a reinforced concrete member strengthened by the new method. A four-point static loading test was carried out to investigate the mechanical behaviour of the beams, with three layers of carbon fibre grid, strengthened by the new method. From the test results, it is cleared that bending theory may be used to the reinforced concrete member strengthened by using laminated plates of carbon fibre grid and polymer cement mortar.
Damage Assessment of Concrete Structures exposed to Fire
Authors: Annerel Emmanuel , Taerwe Luc
Published: May 2013

During a fire, concrete structures behave in most cases very well. It could therefore be of economic interest to repair the damaged structures, as costs for demolition and rebuilding can be avoided and the building can be reused faster. To assess the remaining loadbearing capacity in a scientific based way, information is necessary about the temperature distribution inside the concrete element and the residual material properties of both concrete and steel. But, at least of equal importance is a fundamental insight in how a concrete structure could behave during a heating cycle, as indirect actions due to thermal restraints can occur and cause significant cracking. These effects should be noticed during a visual inspection of the structure, however, cracks introduced by internal thermal restraints are not visible from the concrete surface. In this paper, fundamental knowledge is given about the effect of heating and cooling on the compressive strength of concrete. Diagnosis tools are discussed to obtain the temperature distribution, especially in the neighborhood of the reinforcement. Those techniques are based on the physico-chemical transformations of the cement matrix and the aggregates that occur during heating. To determine the effect of thermal restraints on the structural behavior, a methodology based on finite element methods is illustrated.
Structural retrofitting of older German road tunnels – Possibilities to fulfil current requirements regarding structural fire protection
Authors: Kaundinya Ingo
Published: May 2013

This paper deals with possibilities to update existing road tunnels in order to fulfill up to date requirements regarding structural fire protection. Besides the upgrading of tunnels with structural fire protection systems (like e.g. fire protection sheets) there is also the possibility of numerical investigations. In research projects carried out on behalf of the Federal Highway Research Institute (BASt) numerical investigations for the proof of sufficient structural fire protection have been done for common road tunnel types. Additionally the influence of different fire loads and fire durations on the bearing capacity of the structures have been investigated. The results of these research projects have been used to define a procedure how to investigate existing tunnels regarding structural fire protection. The research results have also been the basis for a current update of national standards for tunnel construction.
Assessing the structural safety of underground frame structures subjected to fire loading
Authors: Zeiml Matthias , Amouzandeh Aram , Ring Thomas , Zhang Yiming , Lackner Roman
Published: May 2013

A nonlinear analysis tool to assess the structural safety of underground frame structures under fire loading is presented. The material and numerical model is validated by comparison of the numerical results with experimental data from large-scale fire experiments. Benchmark examples (real tunnel cross-sections) are analyzed, illustrating the advantages of the nonlinear over a linear-elastic analysis regarding an economic reinforcement design as well as the realistic prediction of the deformation behavior. Future work focuses on introduction of the realistic, nonlinear analysis tool in engineering practice as well as in design guidelines.
Tunnels under Fire – Higher Safety Due to Current FEM Practice
Authors: Müllers Ingo , Böing Tobias
Published: May 2013

Tunnels are key elements in modern traffic networks. Therefore, potential consequences of their failure due to fire can be very high. A failure of a tunnel can lead to disproportionate cascade effects affecting the whole urban infrastructure system. Having this in mind, it is absolutely important to design tunnels against fire adequately. Hence, restraints due to thermal flux into the tunnel section, the effects of spalling of the concrete cover and decreasing material resistance of concrete and reinforcement have to be considered during the calculation. The authors show how tunnels can be designed taking all these circumstances into account by using modern FE-codes. The design procedures are conducted following strictly the existing codes (Eurocodes 1 and 2). Furthermore, it is shown that today plane as well as spatial structure subjected to fire can be analysed adequately.
Case Study: Dealing with Reliability and Availability on Refurbishments
Authors: Eikelenboom Dirk , Allas Gordon
Published: May 2013

The case study aims to investigate how to approach R&A-related uncertainties in refurbished structures. In this specific project, the refurbishment comprised two parts. In the first part (western and central locks), the failure data of the existing structure elements were excluded due to lack of failure and inspection data. In the second part (eastern locks), failure data were included by following these steps:

(Quick) Failure Mode, Effects, and Criticality Analysis (FMECA) to establish critical parts of the structure;

Set up inspection programme for critical parts and translate inspection results to failure data;

Use failure data in the Fault Tree Analysis to determine how they affect the design;

Adapt the design until RA demands are met.

Despite realistic availability figures for the new structure elements, these figures in the first part do not represent the availability of the complete structure due to incomplete data. The second part, however, provides useful availability figures for the entire structure (existing and new). This approach allows the contractor to guarantee the reliability and availability of the whole refurbished structure.

Although this is common practice in the automotive and aerospace industry, this approach is relatively new for civil structures. The designers thus require a different mindset during the design process.
A simplified method for the quick assessment of bridge decks
Authors: Papasotiriou Nikos
Published: May 2013

This paper presents a quick but accurate method for the assessment of bending moments and deflections in simply supported bridge decks by the use of distribution coefficients under the action of Load Model 1 (LM1) as per, EN 1991-Part 2: Traffic loads on bridges. The current work builds on previous research presented by the author and Ryall M. J. [1] as the assessment of stress resultants and displacements in bridge decks by the use of distribution coefficients.

The method named as D-type is based in the assumption that the bridge deck can be analysed as a continuum or semi-continuum and can be defined by the use of characterizing parameters α and θ which model the flexural and torsional rigidities of the deck and they are unique for a particular orthotropic deck. The loads are analysed in harmonic components and the width of the deck and the distance of the load from the edge of the deck are considered as controlling factors. A simple distribution factor D is defined, relating the maximum overall longitudinal bending moment due to the design vehicle load to the peak of the transverse distribution across the deck.

A computer program has been developed and used to carry out a parametric study resulting in distribution coefficient values for a wide range a bridge decks due to a variety of live loading specifications. The results can be presented in the form of tables or charts. The program also enables the user to analyse a single bridge deck and obtain a transverse distribution profile of the shear forces, bending moments, torsion moments, rotations and deflections at a given section under the action of various traffic loadings specifications.
Train-bridge interaction influence on the safety of a short span railway bridge
Authors: Rocha João Miguel , Henriques Abel , Calçada Rui
Published: May 2013

The behaviour of short span railway bridges is known to be particularly difficult to predict due to the complex coupled train-track-bridge system, as well as for being particularly sensitive to resonant phenomena. The objective of this paper is to evaluate the safety of this type of structure inserted in high speed railway lines, bearing in mind the real variability of the parameters that influence the bridge dynamic response. This requires the definition of variables related to the structure, the train, the track and also the wheel-rail contact. Simulation techniques are used to evaluate the structural safety. The system behaviour is assessed by analysing the results obtained using two distinct methods: the moving loads method and the train-bridge interaction method. This allows assessing the influence of the train-bridge interaction effects on the dynamic response of the bridge, confirming ist importance for the analysis of short span structures, particularly under resonant speeds.
A Numerical Investigation for Optimization of the Load Carrying Capacity of a Swiss Rockfall Protection Gallery
Authors: Khasraghy Sara Ghadimi , Kishi Norimitsu , Vogel Thomas , Alvarez Manuel
Published: May 2013

A variety of natural hazards can endanger the built environment and the lifeline in the Alpine areas of Switzerland. Due to climate changes, rockfall events are among the increasing hazards over the last decades. Rockfall protection galleries are one of the few adequate structural measures, which provide the required safety against falling rocks. They are typically composed of reinforced or post- tensioned concrete slabs covered by a soil cushion layer. Many of the existing galleries in Switzerland were built in the 1970s and 1980s. An accurate evaluation of their load carrying capacity is important for the decision-making on their strengthening and possible further use.

Recent developments allow improving the energy absorption and thus the performance of these structures through the use of alternative cushion materials.

The present paper covers a numerical investigation of the impact load carrying capacity of an existing rockfall protection gallery, which is situated below the Lopper cliff at the shore of Lake Lucerne in Switzerland. The numerical results obtained from explicit finite element analyses indicate that the gallery may not be able to perform satisfactorily if it is subjected to the maximum impact energy resulting from an extreme rockfall event with a return period of 100 years. In addition, the possibility of improving the performance of the gallery is examined through a comparison of the slab responses when covered by three different cushion materials, namely gravel, sand, or a so-called Three-Layered Absorbing System (TLAS). The comparison confirms that the performance of the gallery can be optimized by using a cushion material with a better energy absorption capacity than the original gravelly soil, which is currently in place covering the gallery.
An Early Warning Approach for Monitored Bridges Based on the HLM Indices
Authors: Qu Bing , Xiao Rucheng , Sun Bin , Zhang Liwen , Yu Qianhui
Published: May 2013

An early warning method based on the HLM indices for monitored bridges is proposed in this paper. Only three basic values, the highest value, the lowest value and the mean value in each periodicity (daily periodicity, weekly periodicity, lunar periodicity, etc.), are reserved in this method. These values are categorized and added to corresponding sub-tables of the periodical database. Based on these three key values, a series of mathematical models of early warning indices is established to make a statistical analysis of bridge behavior. The indices include the load-carrying capacity index, loading intensity index, volatility index and directional movement index. This method has already been successfully applied to Yufeng bridge health monitoring system in China’s Jiangsu Province and achieved fine results.
Bridge Health Monitoring: A Proposal to Preserve Egyptian Bridge Network
Authors: Yehia Ebtisam , Khalil Ayman , Elbehairy Hatem , Abdelrahman Amr , Essawy Ahmed
Published: May 2013

In the last few decades, Bridge Health Monitoring (BHM) has become a major demand to preserve the bridge wealth worldwide. BHM is a process aiming at providing accurate and in-time information concerning structural condition and performance. In order to establish BHM system in Egypt, accurate definition and classification of bridges, common defects, and available resources are required. The bridge network in Egypt consists of more than fifty thousand bridges and about 50% of these bridges were built before 1970. These bridges need to be evaluated to ensure their safety and serviceability to maintain their function and efficiency. In this paper, an investigation was carried out on a sample of Egyptian bridges in the ownership of the General Authority of Roads and Bridges (GARBLT) included 1249 bridges. The bridge sample under concern is classified according to their construction date, construction material, statical system, span length, bridge location and deck type. In addition, finite element (FE) models were generated for a selected number of bridges to extract its dynamic properties (frequencies, modal shapes). Changes in dynamic properties for several defect scenarios were estimated. More detailed FE models for common bridge types through group of shell element models expressing damage propagation at high flexural zones were developed. Modal properties corresponding to each damage step were extracted. Different damage indicators were adopted and calculated at each damage step providing tables indicating deterioration propagation. Deterioration tables for each bridge were considered a database to establish bridge management system (BMS) to prioritize maintenance, repair and rehabilitation (MR&R) activities. Prioritization of bridges was performed through proposed model solved by genetic algorithm (GA) software. Results proposed by GA solver were compared to traditional prioritization methods in order to indicate prioritization efficiency and will be discussed in another paper.
Extreme action effects in reinforced concrete bridges from monitoring
Authors: Treacy Mark A. , Brühwiler Eugen
Published: May 2013

The need to maximise the lifetime of existing road bridges necessitates clear and efficient tools for engineers to perform structural safety verifications based on monitored data. This study develops methodologies for ultimate limit safety (ULS) verification of reinforced concrete elements using directly measured action effects. The paper incorporates results from a prestressed concrete highway bridge in Switzerland equipped with a structural health monitoring (SHM) system. The design considerations for the monitoring regime are presented. Estimates of the extreme traffic action effects for a given return period are obtained from daily block maxima results using a generalised extreme value approach. A number of factors are found to have a significant effect on the observed results, most notably the duration of monitoring.
Study on applicability of high durability friction grip joints with high strength countersunk head bolts for steel bridge structures
Authors: Tabata Akiko , Kanaji Hidesada , Kurono Yoshihide , Yamaguchi Takashi
Published: May 2013

The authors focused on the high strength bolted friction grip joints with countersunk head bolts which can finish the surface of the connection plate flat smoothly and prevent from functional depression due to corrosion. Firstly we carried out Finite Element Analysis in order to evaluate the contact pressure of double shear connected friction joints with countersunk heads varying the angle of countersunk head. Secondly, we have compared the slip strength of the joints which has the optimum countersunk head angle with that of the joint with the normal high strength bolt through the standard slippage test considering variation of plate thickness and the yield strength of the base and splice plates. As a result, it was concluded that the slip strength of the joints with countersunk heads exceeds the required design slip strength which has specified in JSHB and that its slip coefficients is about 10% lower than that with normal head bolts.
Dynamic Serviceability and Traffic Safety Assessment and Upgrading of Historic Railway Bridges
Authors: Majka Michal
Published: May 2013

The paper discusses the application of modern computational dynamic analysis to the assessment of the dynamic performance of historic railway bridges. The phenomena, such us dynamic amplification, serviceability-critical bridge and train accelerations, as well as bridge-train interaction and resonance are outlined and discussed. The background to the current serviceability requirements, based on the UIC and Eurocode recommendations is provided and these requirements are discussed. This is followed by applications demonstrating the use of the advanced dynamic analysis in the assessment of railway bridges. Examples include historic bridges that were analysed to assess safe operational speeds, based on the serviceability criteria. Means of improving the dynamic performance of these bridges are examined and discussed.
Study on Slip Behaviour of High Strength Bolted Friction Type Joint with Extremely Thick Plates by Using Finite Element Analysis
Authors: Takal Toshikazu , Peng Xue , Sun Honghe , Yamaguchi Takashi
Published: May 2013

High strength bolted friction type joints are commonly used to join members of steel bridge structures. Recently, such joints have become larger, because members of bridges tend to be large to seek structural simplicity. Since large members consist of extremely thick plates, large size joints are needed with many bolts in a line, containing thick plates including splice plates. It is of concern that many bolts and thick plates affect the slip behaviour of such large size joints. So, FEA focused on joints with many bolts and thick plates is carried out. Based on the results, it is clear that a non-uniform distribution of friction force exists. And, it is also shown that a certain combination of thicknesses of connected plates and splice plates has the large capacity of slip resistance. It is concluded that such results can be explained by the influence of the additional bending moment due to thick plates.
Analysis on modal frequency variation of a cable-stayed bridge based on monitoring data
Authors: Sun Limin , Zhou Yi
Published: May 2013

Although modal parameters are common indexes of structural global conditions, they would be influenced by environmental factors, such as temperature, wind and traffics; therefore it is necessary to investigate the correlations of these environmental factors and the structural modal parameters. Based on the 5 years' monitoring data recorded by Donghai Bridge Structural Health Monitoring System (DBSHMS), this paper studied the first two bending modal frequencies of the main navigation channel bridge (MNCB). The spectral analysis showed that the variation of modal frequencies possessed some dominant cycles such as 1 year, 1 week, 1 day, 12 hours and so on. By correlation analysis and regression analysis, the paper discussed the reasons for those dominant cycles of modal frequency variation from the viewpoint of temperature and traffic loading's effects.
Static and Dynamic Analysis of the Railway Bridge on the Line Devínska Nová Ves - Štúrovo (The Red Bridge) at km 51.368
Authors: Turinic Lubomir , Huekl Martin
Published: May 2013

Toward the end of 2011 a static and dynamic analysis of the railway bridge situated at km 51.368 of the line Devínska Nová Ves – Štúrovo have been carried out. Calculations were performed to assess the bridge carrying capacity with regard to the load imposed to it by rail traffic and to analyse the effects of various burden types on its stress state, particularly on its rail deck and its main beams. The dynamic analysis investigated the effects of service load at various speeds to determine critical points of the structure. The evaluated stress range spectra resulting from a train passage have served to determine the residual life of the Red Bridge structure.
Testing the Properties of Structural Cast Steel (Flußstahl) in Old Railway Bridges
Authors: Hołowaty Janusz , Wichtowski Bernard
Published: May 2013

The long-term use of steel bridges leads to changes in the mechanical properties of their structural steels. This issue is demonstrated in a study of cast steels from four railway truss bridges built in 1875. The tests for each bridge involved: an analysis of the chemical composition, determination of hardness and toughness, along with yield strength and ultimate strength. These tests made it possible to calculate the degree of degradation and current mechanical properties of the steels.
Fatigue Assessment of Steel Bridge Superstructures, the Netherlands
Authors: Breider Janwillem , Nagtegaal Gerland , Tuinstra Dimitri
Published: May 2013

RWS has appointed the Managing Contractor (MC) in 2009 to manage the renovation of eight steel highway bridges in the Netherlands. Part of that project exists of fatigue assessment of the existing structures and strengthening works. The MC has used a fatigue analysis tool to assess the fatigue damage in the superstructures. The tool is used to automate the analysis process. Assessing the bridges with the detailed load model results in less fatigue damage compared to standard Eurocode fatigue load models and limits the magnitude of repairs on the bridges, but also results in large amounts of data to be processed. The automated fatigue analysis tool allows the structural engineer to conduct an extensive detailed fatigue analysis in a few hours time, and delivers ample results to give insight in the fatigue behaviour of the bridges.
Safety Standard for Existing Structures
Authors: Steenbergeen Raphaël
Published: May 2013

A safety philosophy for evaluating and upgrading existing structures is of great value. For a large part of the existing infrastructure and buildings the design life has been reached or will be reached in the near future. These structures need to be reassessed in order to find out whether the safety requirements are met. Not only for new structures but also for the existing stock the Eurocodes are starting point for the assessment of the safety. However, it would be uneconomical to require all existing buildings and civil engineering works like bridges to comply fully with these new codes and corresponding safety levels. The assessment of existing structures differs from the design situation on three main points. Increasing safety levels usually involves more costs for an existing structure than for structures that are still in the design phase. The remaining lifetime of an existing structure is often less than the standard reference period of 50 or 100 years that applies to new structures. For an existing building or bridge structure actual measurements with respect to geometry, material properties and behaviour under normal or design circumstances may be made in order to reduce uncertainty. In the design philosophy both economic arguments and limits for individual human safety play a role. This paper gives guidelines for establishing reliability indices for existing structures.
Assessment of existing bridges based on probabilistic methods – Background and proposal for a practical approach
Authors: Braml Thomas , Wurzer Otto , Morgen Karl
Published: May 2013

The maintenance of existing civil engineering structures is becoming ever more important. The consequence of this is that the realistic assessment of existing structures both from a static - design point of view as well as in respect of the remaining service life will be one of the main tasks of engineers in the future. Amongst the various scientific methods for assessing the load bearing capacity and serviceability are probabilistic calculation methods. Using these methods, it is possible, based on stochastic models for the loads and resistances to determine, in particular, the failure probability or the reliability of civil engineering structures. The report presents a practical procedure for the assessment of existing structures with the help of probabilistic calculation methods. The advantages of these methods are demonstrated using the example of a 440 m long existing prestressed concrete bridge.
Probabilistic approach to fatigue assessment of stay cables
Authors: Baussanron Julien , Sørensen John Dalsgaard , Toft Henrik Stensgaard , Yalamas Thierry
Published: May 2013

In structures submitted to repeated variable loads, initiation and growth of cracks in the material are one of the most common causes of the deterioration of structures, especially in combination with corrosion. Under variable amplitude and repeated loads, some local cracks initiate on critical points of the structures, develop into critical cracks and failure due to fatigue.

Many parameters used for predicting times to failure of structure due to fatigue are uncertain and their variations have a big influence on the real lifetime. This paper will focus on a global methodology to take into account main sources of variability in fatigue prediction for stay cables in cable stayed bridges. The first step of this methodology is to model the variability of each parameter. Loading is one of the most important sources of variability. Another important source of variability is the fatigue strength of the material. Probabilistic Wöhler curves are fitted using available data, and used to represent the variability of material fatigue behaviour. Finally, the reliability is assessed using Monte Carlo simulations.
Investigation of concrete structures in Serviceability limit state using energy principles
Authors: Hagsten Ears German , Fisker Jakob
Published: May 2013

In this paper, a method concerning analysis of reinforced concrete structures in the serviceability limit state (SLS) is discussed. The method is based on elastic energy principles, combined with simple assumptions with respect to concrete mechanics.

This approach allows for a direct implementation of the choices, made in relation to the design of the structure with respect to the ultimate limit state (ULS). Hence, a rational link between the two states is established.

The approach is appropriate for the design of new structures and assessment of existing structures.

The method and the link between the choices made regarding the ULS and the state of stress in the SLS is compared with tests on reinforced concrete disks and beams, respectively. Fairly good agreement between theory and tests is achieved.
Determination of Accidental Actions for the Remaining Lifetime of Bridges
Authors: Kunz Claus
Published: May 2013

Existing bridges have sometimes to be evaluated considering ship impact. Using present codes for accidental actions would often lead to rehabilitation measures or to new structures which might not be efficient regarding the rareness of the serious ship collision events to bridges. Therefore a method has been developed to determine ship collision forces as time-dependent action for the remaining lifetime of an existing bridge. This method, called remaining life expectancy concept, is based on the design concept of the Eurocodes which is a reliability-based design procedure. It considers the principles of the common maintenance strategies and allows the safe and economic verification of existing bridges considering their experienced lifetime. The contribution explains the methodology of modern ship impact determination by combining a load model with a probabilistic model as it is used for the design of new bridges. The adaption to remaining lifetime adapted dynamic impact forces is shown.
Sensitivity Study for Computational Assessment of Prestressed Concrete Bridges
Authors: Borkowski Gregor , Baur Michael
Published: May 2013

A current challenge for civil engineers is the conservation of existing infrastructures which includes maintenance, assessment and, if necessary, strengthening according to new code requirements. For the evaluation of the actual load carrying capacity and the remaining service life, detailed knowledge of the material properties and a realistic structural model is required. If necessary, the latter has to be adjusted for existing structures by in-situ measurements and inspections. In this paper, the structural behaviour of a concrete hollow box girder bridge is investigated by nonlinear analysis with a 3D finite element model. Based on these results a sensitivity study is performed by variation of material properties.

In a previous case study it was shown how eccentrically arranged traffic loads are inducted into the bridge-system and in which way the maximum stressing of a cross section could be calculated. For this, a 3D finite element model with the assumption of nonlinear material behaviour was used.

In a first step the redistribution of section forces in the transverse and longitudinal direction of the structural system due to nonlinear material behaviour is discussed. It will be shown in which way the force flow is influenced by nonlinear material behaviour in comparison to a linear elastic analysis. Second, the ultimate limit state (ULS) is discussed by means of a sensitivity analysis.

Finally, the influence of the used material assumption and the statical system in nonlinear calculations to the load bearing capacity is discussed. This might help in the judgement whether the service life of a bridge can be reached or a strengthening is necessary.
Probabilistic Reliability Assessment of Industrial Heritage Bridges
Authors: Sýkora Miroslav , Holický Milan , Marková Jana
Published: May 2013

Methods for reliability assessment of bridges registered as industrial heritage are developed taking into account principles of EN 1990, ISO 13822 and ISO 2394. A proposed probabilistic procedure allows for consideration of new information obtained from inspections or monitoring and satisfactory past performance. Application of general principles is illustrated in the assessment of a reinforced concrete road bridge. The study reveals that reliability assessment of bridges registered as industrial heritage can be based on probabilistic methods. Modelling of degradation processes seems to be a key issue of the reliability analysis.
Structural Design of the Vroenhoven Bridge, Riemst, Belgium
Authors: Dister Vincent , Bols Bart , Ney Laurent
Published: May 2013

The once-standing, now-demolished bridge of Vroenhoven had become an obstacle for water traffic due to the enlargement the Canal Albert to a clearance gauge for vessels up to 9000 tons, linking Liège and Antwerp. The existing bridge and nearby bunker were classified in 1995 as unique remnants of the battle on 10 May 1940 when Germany invaded Belgium. In spite of this classification, the government decided to replace the existing bridge. The new project consists of two distinct large-scale elements: a bridge and building. The building enabled the conservation of the classified bunker. The new bridge is a cable-stayed bridge with a total length of 195m including 3 spans. The width of the composite bridge deck is 18,24m.

This article will describe the principle characteristics of the project and the ways in which the conservation of a classified feature significantly influenced the phasing of the construction, and the design consequences.
Partially in situ protection of a historic building and a design case combined
Authors: Zhao Xuqian , Shen Chun , He Sixiang , Xia Lin
Published: May 2013

The use of external walls of a historic building as the decorative walls of the new high-rise building is presented here. In situ protection of historic walls has become very difficult due to the restrictions of the construction site, as well as the excavation of the foundation pit. At present, there is lack of similar experience in China. In this paper, a new design method through specific construction measures, computational analysis and experimental verification, is used to ensure that the external walls of the historical building and the new building are connected to each other firmly throughout the entire construction phase. The deformation, strain and dynamic characteristics of the external wall are monitored during the construction process. The latest monitoring data are used to adjust the calculation model and the design method to provide a reliable safety guarantee in the entire construction phase. The design method proposed in this paper will be useful for conservation of historic buildings in situ.
Tunneling underneath historical buildings of Delft
Authors: Mortier Hans , Delfgaauw Steven
Published: May 2013

In the city of Delft, the existing two track railway viaduct will be replaced by a 2,4 km four track railway tunnel. The tunnel runs through the historic city centre and replaces a railway flyover, which divides the town in two parts. The shallow tunnel is executed using a top down building sequence using diaphragm walls. The alignment of the tunnel is projected below two structures of historic value. One of these structures is a still functioning windmill, called The Rose, built in the 16th century. The other structure is a medieval tower, The Beguine Tower, which was part of the fortification wall that surrounded the city of Delft at that time. To pass below both structures with the tunnel works, two different execution methods were defined.

Below both structures temporary reinforced concrete slabs were cast, and after hardening of these slabs the subjacent foundations were separated from the structures above, which – in the mean time

- were taken over by an alternative foundation. Then, the historical buildings were moved in such a way, the diaphragm walls and future tunnel deck could be built at that location. Finally, both the mill and the tower were replaced back to their original location, but now on top of the new tunnel deck. Then, the top down construction process of the remaining tunnel works took place.

The article will focus upon execution techniques, allowed deformation criteria and the design models applied.
Fatigue safety examination of a riveted railway bridge using data from long term monitoring
Authors: Brühwiler Eugen , Bosshard Max , Steck Pirmin , Meyer Christian , Tschumi Marcel , Haldimann Senta
Published: May 2013

Long term monitoring of structural elements of a 115 years old riveted railway bridge structure of high value as cultural heritage has been conducted. Monitored values were exploited by Rainflow analysis and served as the basis for the fatigue safety verification. As the locations of measurements are generally not identical with the cross sections of verification, measured strains were translated to the relevant verification cross section by means of factors that were determined by structural analysis. Using these values, all fatigue relevant structural details were first verified with respect to the fatigue limit. Then, damage accumulation calculation according to the Palmgren-Miner Rule was performed for those elements where the fatigue limit check was not fulfilled. Sufficient fatigue safety could finally be verified for the entire riveted structure and additional service duration of at least 50 years for this riveted structure could be validated.