bluuebunny/crossref_metadata_2025_split huggingface dataset:
13.11: DSM design approach for hot‐rolled steel angle columns
Authors: Dinis Pedro Borges , Camotim Dinar , Vieira Luís 
Published: September 2017

ABSTRACTThis work reports the latest results of an ongoing investigation on the Direct Strength Method (DSM) design of hot‐rolled steel equal‐leg angle columns with fixed and pinned (cylindrical or spherical hinges) supports and short‐to‐intermediate lengths, i.e., buckling in flexural‐torsional modes. It extends the scope of similar studies carried out by the authors for cold‐formed (higher leg width‐to‐thickness ratios) steel angles with the same characteristics. After reviewing (i) the most relevant findings unveiled in the studies concerning hot‐rolled steel angles, including the role played by residual stresses in eroding their ultimate strength, and (ii) the available experimental and numerical failure load data, comprising fixed‐ended and pin‐ended columns with several geometries (cross‐section dimensions and length) and reported by various researchers, the paper briefly addresses the mechanical reasoning behind an efficient DSM‐based design approach proposed by the authors in the context of cold‐formed steel (slender legs) short‐to‐intermediate angle columns. Then, the available failure load data is used to assess the quality of their estimates provided by this DSM design approach, including the determination of the corresponding Load and Resistance Factor Design (LRFD) resistance factors. It is shown that the proposed design approach can be also successfully applied to predict hot‐rolled steel angle column failure loads, leading to LRFD resistance factors above the value currently prescribed, for compression member design, by the North American Specification (ϕc=0.85).
13.13: Earthquake loss assessment of steel moment‐resisting frames designed according to EC8
Authors: Macedo Luís , Castro José Miguel 
Published: September 2017

ABSTRACTThe development of damage in buildings is implicit in the seismic design process. However, stakeholders and building owners generally have the perception that code design provisions ensure safe and minor damaged buildings for any seismic intensity level. It is therefore crucial to provide support decision information, which can help stakeholders and building owners taking informed selection of design opinions. Most recent design and assessment standards/guidelines define several performance levels seeking to ensure that structures exhibit appropriate behaviour and protection at different seismic intensity levels. Moreover, for steel moment‐resisting frames (MRFs), EC8‐3 defines the building performance acceptance criteria at different performance levels by ensuring that local deformation demands are lower than pre‐defined local deformation capacities. The main objective of the research presented in this paper is to evaluate the expected direct economic seismic losses of steel moment‐resisting framed structures designed according to Eurocode 8. To this end, the PEER PBEE methodology with the improvements proposed by [1] was implemented and used. A set of 30 archetype buildings, representative of the current building stock, were designed according to Part 1 of Eurocode 8 (EC8‐1) using three different behaviour factors (q). The EC8 proposed upper limits for the behaviour factor (q) and the behaviour factor obtained from an Improved Force‐Based Design (IFBD) procedure have been used [2]. The expected economic losses and its disaggregation were evaluated for the EC8‐1 and EC8‐3 seismic intensity levels, allowing in this way to characterize the performance with improved seismic performance metrics which can help stakeholders and building owners to take their decisions.
13.16: Design of tension components: Revision and further development of EN 1993‐1‐11
Authors: Annan Rachid , Bechtold Martin , Friedrich Heinz , Kemmler Roman , Misiek Thomas , Numminen Veikko , Ruff Daniel C. 
Published: September 2017

ABSTRACTThe paper gives an introduction as well as background information on proposed changes and amendments in EN 1993‐1‐11 “Design of structures with tension components”, implemented during the ongoing revision. Due to some deficits in the currently applicable standard this revision is not only limited to some restructuring and editorial changes, but includes also major technical changes in the following fields: safety concept and structural analysis, actions and loads, robustness and reparability, design of tension components and design of clamps and saddles.
14.05: A mehcanical model of composite floor systems under internal column‐removal scenarios
Authors: FU Qiu Ni , TAN Kang Hai , YANG Bo 
Published: September 2017

ABSTRACTSlabs play a vital role in enhancing structural capacity to resist progressive collapse. However, there are only some qualitative suggestions rather than quantitative provisions in the current codes and design guides concerning the beneficial effect of slabs to mitigate under progressive collapse. Therefore, a mechanical model for calculating load‐carrying capacities of floor systems against progressive collapse is timely and necessary. In this paper, a new mechanical model is proposed to quantify load‐carrying capacities of 3D composite floor systems for internal column removal scenarios. The assumptions, simplifications and failure criteria of the model, which are based on the results of validated numerical analyses and other researchers’ tests, are introduced first. After that, the derivations of the proposed model are discussed. Then, the static load‐displacement responses obtained from this model are compared with the test results. Good agreement is obtained between the model and the test results.
15.05: The experiment of H‐shaped beams with continuous restraint on upper flange
Authors: Sano Tatsuhiko , Ikarashi Kikuo , Ohnishi Yuki , Shirai Daigo 
Published: September 2017

ABSTRACTThis study aims to investigate the elastic–plastic behavior of H‐shaped beams with continuous, complete restraints on the upper flange through a static loading test, and to understand the effect of restraint and the influence of raising the neutral axis. In the loading test, the upper flange is restrained using a restraint device with four hinges. The shifting of the neutral axis position is simulated by increasing the shape of the upper flange. The following conclusions are drawn from the results: (1) The continuous, complete restraint on the upper flange significantly increases the maximum strength and the plastic deformation capacity of the beam with respect to the lateral buckling. The buckling waves are observed close to the fixed end. (2) The continuous, complete restraint on the upper flange slightly increases the maximum strength and plastic deformation capacity of the beam in the local buckling of the web, and has no effect on the beam considering the local buckling of the flange. (3) The elastic web local buckling of the H‐shaped beams with a continuous, complete restraint on the upper flange occurs easily because the neutral axis shifts its position. The plastic deformation capacity of the beam may have been reduced.
15.10: Probabilistic analysis of steel columns under blast induced loads
Authors: Karlos Vasilis , Solomos George , Larcher Martin 
Published: September 2017

ABSTRACTA growing interest for the design of structures to sustain blast induced loads has been observed in recent years due to the worldwide rise of terrorist bombing attacks. The blast parameters that are essential for design can be located in various publically available blast design manuals, where the proposed graphs and equations are based on a large experimental database established several decades ago. The degree of uncertainty in the determination of these parameters is significant, as a result of the unstable nature of explosives, the efficiency of the measuring equipment and the large pressure and impulse values involved in the blast phenomena.These uncertainties have been identified in the current study which focuses on the response of steel open sections under blast induced loads and addresses the influence of such uncertainties on the flexural response of axially loaded structural members. The variation of structural and load parameters was considered in the design procedure by utilizing a reliability‐based assessment methodology. A probabilistic approach was followed and the reliability of the column was defined with respect to limit states proposed in various blast design manuals. Probability curves are constructed, by using single‐degree‐of‐freedom models, showing the cumulative probability distribution of reaching a certain capacity with respect to a selected limit state. This way instead of a deterministic safe‐unsafe criterion in design, the probability of damage is introduced in relation to the applied axial load, which provides a valuable insight to the behaviour of structural members subjected to an explosion.
15.11: Lab testing and modelling of thermal break assemblies: Mitigating structural penetrations in building envelopes
Authors: Hamel Scott , Peterman Kara 
Published: September 2017

ABSTRACTThe large temperature differentials between inside and outside spaces in Alaska (>100°F) has triggered the use of thermal‐break details for envelope point protrusions for decades, mostly to prevent condensation on interior structural members. This has been done, however, using engineering judgment, and, prior to this study, no experimental or computational analysis has been conducted on the effectiveness of these details.This study outlines a series of thermal and structural tests of thermal bridges and thermal break details for steel sections protruding through the building envelope such as for canopies or rooftop mechanical units. The results of the experimental data will be correlated with thermal finite‐element models to provide insight on the modelling parameters. The results show that some details, while decreasing the potential for condensation, actually increases the overall heat flow through the detail, when compared to the control condition with no thermal break.
15.12: On imperfection‐sensitivity evaluation of BMRF systems: Buckling and post‐buckling responses
Authors: Lotfollahi Mehrdad , Alinia Mohamad Mehdi , Taciroglu Ertugrul 
Published: September 2017

ABSTRACTSensitivities of the buckling and post‐buckling responses of braced moment resisting frame (BMRF) systems to initial imperfections in their gusset‐brace sub‐systems are studied. Previously, the effects of imperfection amplitude and type have not been evaluated in requisite detail, and only a general recommendation—which is given as a function of the bracing element's length—has been utilized. Here, highly detailed (centimeter scale) three‐dimensional finite element models are employed in parametric sensitivity analyses to quantify the effects of imperfections on the responses of BMRFs with diagonal and X‐bracing subsystems. The results are discussed and amendments are proposed to the existing empirical equations for evaluating the buckling and post‐buckling capacities of imperfect bracings. The parametric studies showed that while an increase in the imperfection amplitude can dramatically decrease the initial buckling load of BMRFs, this causes only moderate decreases in their post‐buckling strengths, and their ultimate states remain nearly unaltered.
15.13: Discrete sizing optimization of trussed steel portal frames according to Eurocode 3
Authors: Van Mellaert Roxane , Mela Kristo , Tiainen Teemu , Heinisuo Markku , Lombaert Geert , Schevenels Mattias 
Published: September 2017

ABSTRACTThis paper presents a new method to find the global solution of combined truss‐frame sizing optimization problems taking into account all relevant Eurocode constraints. The approach is based on a reformulation of the optimization problem as a Mixed‐Integer Linear Programming problem (MILP) which is solved by means of a branch‐and‐bound method. A portal frame that consists of both beam and truss elements is adopted as a test case. The optimal sections of the portal frame have to be selected from a square hollow sections catalog. The design of the portal frame has to meet the requirements prescribed by the Eurocodes. These requirements are adopted as constraints by reformulating them as or approximating them by a linear equation. Not only the Eurocode constraints related to member strength and stability but also all Eurocode constraints related to the joints of the structure are taken into account during the optimization. As a consequence, a post‐processing step to account for other constraints is avoided, therefore optimality is retained and additional engineering time is reduced. The optimization results are presented and the influence of the different Eurocode constraints on the optimal design is discussed.
15.15: Dynamic Analysis of Steel‐Concrete Composite Building Floors Subjected to Human Rhythmic Activities
Authors: Campista Fernanda Fernandes , da Silva José Guilherme Santos 
Published: September 2017

ABSTRACTThis work aims is to investigate the structural dynamic response of steel‐concrete composite floors, when subjected to rhythmic human activities, based on experimental tests and numerical modelling, from the point of view of human comfort. The main focus of this paper is to study the effect of the dynamic interaction between the occupants and the floors, representing these people by SDOF biodynamic models (mass‐spring‐damper systems), in order to better evaluate the dynamic response and the vibration serviceability states. This way, the investigated structural model is related to a steel‐concrete composite building which is composed of three floors used for aerobics classes, with dimensions of 20m × 20m, a total area of 1200m2 (3 × 400m2) and a ceiling height of 4m. The numerical modelling of the structure was performed by ANSYS program and was based on the finite element method (FEM). In order to evaluate the dynamic response of the investigated steel‐concrete composite building, accelerations associated with 32 individuals practicing rhythmic activities were experimentally obtained to introduce them into the finite element model. Thus, the dynamic response of the building floors was evaluated in terms of the peak accelerations, RMS and VDV values, according to human comfort criteria and considering situations of the design practice.
16.03: Structural analysis of the historical Széchenyi: chain bridge in Budapest
Authors: Kövesdi Balázs , Dunai Péter , Dunai László 
Published: September 2017

ABSTRACTThe superstructure of the historical Széchenyi chain bridge in Budapest was reconstructed several times in the history and currently the renewal of the bridge is under design. The independent static check and expertizing tasks of the renewal process were completed by the Budapest University of Technology and Economics Department of Structural Engineering. During the project numerous specific interesting structural problems and modeling specialties turned out, which comes from the layout of the old historical structure, from the long time traffic and from the corrosion, which required a detailed structural analysis. The current paper presents the typical failure modes observed on similar historical chain bridges all over the word, which gives an impression on their weak‐points to be checked with special attention. To determine the load carrying capacity of the renewed structure and to check the fatigue performance of the old structural details a detailed numerical model is developed. The global model was used to simulate the structural behavior of the whole structure. Local models are used to model the effect of corrosion, the friction between the chains and the pin, and to model all the uncertainties in the design procedure using probabilistic design. The application of advanced analysis methods and design tools on a historical steel structure are discussed in the paper.
16.05: Evaluation of simplified models for short span bridges: Based on a measured train crossing and included substructure
Authors: Brandstetter Georg , Schobesberger Felix , Fink Josef 
Published: September 2017

ABSTRACTIn recent times numerous studies concerning bridges under dynamic loading through train crossing were made. It was found out that there are significant deviations of the measured field results and the results determined by simulations using conventional beam models for bridges with short spans (up to 10m). It was shown that a simply supported beam is not a sufficient model for these structures, since the influence of the subsoil and the substructure cannot be neglected for short bridges.The main goal of this article is to achieve a better accordance between the measured and the calculated results. Therefore, the model of the simply supported beam is expanded at both supports by: vertical springs and additional nodal masses. Also, different models for the load are examined. To evaluate the quality of this models, an acceleration measurement of a 4m span bridge during a train crossing is used.It is shown that the measured accelerations can be predicted with acceptable accuracy with an extended beam model by including the load distribution through the rails and the ballast layer (by the method suggested in Eurocode 1).
16.07: Flange buckling resistance of trapezoidal web girders: Experimental and numerical study
Authors: Jáger Bence , Kövesdi Balázs , Dunai László 
Published: September 2017

ABSTRACTGirders with trapezoidally corrugated web are widely used structural elements in the civil engineering praxis due to their numerous advantages. However, there is a relatively small number of previous investigations focusing on the determination of the flange buckling resistance of the corrugated web girders. Previous experimental and numerical investigations confirmed that the flange buckling resistance model provided by the EN1993‐1‐5 [2] predicts often unsafe results. Therefore, the current paper collects all the previous proposals on the flange buckling resistance and introduces an experimental research program investigating the flange buckling behaviour of trapezoidally corrugated web girders. Based on the test results an advanced FE model is developed, validated and presented. An intensive numerical parametric study is performed on this model to investigate the buckling coefficient and the relationship between the relative slenderness and the reduction factor for corrugated web girders. Based on the experimental and numerical results the current paper introduces an enhanced design method for the determination of the flange buckling resistance. This design method consists of proposal to determine the critical load amplifier of the flange outstand and it also contains a new buckling curve which considers the specialties of the structural behaviour coming from the corrugation profile.
16.14: Operational, ecological and economical assessment of steel railway bridges
Authors: Zinke Tim , Ummenhofer Thomas , Lenz Katrin , Schneider Sarah , Beck Tabea 
Published: September 2017

ABSTRACTAlthough for civil engineering structures commercial assessment approaches such as the British CEEQUAL [1] or the American Envision [2] can be found, no sustainability assessment system specialised in railway bridges exists. Here, system specific aspects like construction types, corrosion protection systems and construction processes must be considered. There is a lack of systematic research showing the advantages of prefabrication, and a small number of rehabilitation activities within the operation stage both leading to fewer obstructions of the railway network. Especially interdependencies of building activities and the operation of trains should be analysed and integrated into the assessment.The paper discusses the approaches and methods essential for a holistic assessment of railway bridges. The special boundary conditions of the rail traffic (compared to road traffic) will be presented. Based on this, economic and ecologic impacts throughout the entire life‐cycle are calculated and operation encumbrance costs caused by the interaction of construction sites and railway operation are shown. This is performed for three types of bridges: a thick plate through bridge, a composite bridge and a tied‐arch bridge.
16.15: Experimental evaluation of a novel demountable shear connector for accelerated repair or replacement of precast steel‐concrete composite bridges
Authors: Suwaed Ahmed S. H. , Karavasilis Theodore L. 
Published: September 2017

ABSTRACTA novel demountable shear connector for precast steel‐concrete composite bridges is presented. The connector uses high‐strength steel bolts, which are fastened to the top flange of the steel beam with the aid of a special locking nut configuration that prevents slip of bolts within their holes. Moreover, the connector promotes accelerated construction and overcomes typical construction tolerances issues of precast structures. Most importantly, the connector allows bridge disassembly, and therefore, can address different bridge deterioration scenarios with minimum disturbance to traffic flow, i.e. (i) precast deck panels can be rapidly uplifted and replaced; (ii) connectors can be rapidly removed and replaced; and (iii) steel beams can be replaced, while precast decks and shear connectors can be reused. A series of push‐out tests are conducted to assess the behavior of the connector and quantify the effect of important parameters. The experimental results show shear resistance, stiffness, and slip capacity significantly higher than those of welded shear studs along with superior stiffness and strength against slab uplift. Identical tests reveal negligible scatter in the shear load – slip displacement behavior. A design equation is proposed to predict the shear resistance with absolute error less than 8%.
16.18: DYNA® link anchor box: Innovative structure for anchoring stay cables
Authors: Gawlista Jannik , Kasper Marcel , Schraml Marcus , Brand Werner 
Published: September 2017

ABSTRACTCable stayed and extradosed bridges are often designed with saddles at the pylon. This results in slender dimensions of the pylon and reduced costs as access shafts within the pylon can be omitted. However, inspection of the deviated strands within the saddle is only possible after exchanging single strands or the complete cable. Furthermore, differential forces in the cables are often transferred within the saddle by friction only. Also, cable installation and stressing have to be carried out simultaneously on both fronts of the form traveller for the most common balanced free cantilever construction method.To find an alternative solution for an improved performance of pylon design, installation cycle and cable inspection, a new curved anchor box has been developed. The DYNA® Link anchor box consists of two sections: in the concrete, there are two steel beams with shear studs for transferring the cable load into the concrete pylon; outside, the concrete the steel beams are connected to each other, and a bearing plate is welded to the steel beams as support for the cable anchorage. An opening at the steel beam provides access for installation and inspection of the cable anchorage. Through this steel anchor box, which is embedded in the solid concrete pylon, two stay cable anchorages are linked to each other and are located outside the pylon. With this design, all advantages of common saddles are kept; the disadvantages are compensated by using a steel composite structure which can be designed and calculated according to national or international standards. In doing so, elaborate testing in accordance to international cable guidelines such as fib or PTI can be omitted as well.