246 research outputs found
Integrity of high strength steel structures: Experimental results
No full textCivil Engineering and GeosciencesStructural Engineerin
Het gedrag van enkele voorspanboutverbindingen uitgevoerd in weervast staal
No full textCivil Engineering and GeosciencesStructural Engineerin
Fatigue resistance of rib-to-deck welded joint in OSDs, analyzed by fracture mechanics
No full textThe orthotropic steel decks (OSDs) are widely used in bridge engineering to support traffic loads. A possible crack, initiating from the weld toe of rib-to-deck welded joint and growing into the deck plate, is studied using linear elastic fracture mechanics. A detailed FE model is created and the results are compared with the fatigue tests published. Good agreement is found between beach marks from experiments and calculated crack fronts in FE. An engineering approach with the crack shape simplified as a semi-ellipse is applied. Geometric correction factors for a hand calculation method is proposed based on the parametric analysis. Using the proposed correction factors, Monte Carlo simulation is carried out with failure criteria defined with respect of the crack depth reaching “50%” of the deck thickness, “75%” of the deck thickness, and the failure criterion “2A FAD” according to BS7910. Predicted results using the failure criterion “75%” show good agreement with experimental data, for 5%, 50%, and 95% survival probabilities. Effects of initial crack shapes and sizes are discussed using the improved hand calculation model. Lower fatigue resistance is found when the initial crack is shallow or large. In addition to the standard weld geometry in which the weld profile is represented by a straight line, concave and convex arc shape weld profiles are studied. Fatigue resistance is improved in the case with assumption of concave arc weld profile. The difference of fatigue resistance between the cases with a straight line and convex arc weld profiles is small.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Steel & Composite Structure
Handleiding ten behoeve van de laboratoriumoefening g8 Studiejaar 1980-1981
No full textCivil Engineering and GeosciencesStructural Engineerin
Tensile testing of FCL M36 connectors
No full textCivil Engineering and GeosciencesStructural Engineerin
Site measurements Lekbridge Hagestein 2006
No full textCivil Engineering and GeosciencesStructural Engineerin
Mechanical Behaviour and Durability of FRP-to-steel Adhesively-bonded Joints
No full textDuring the last two decades, fiber-reinforced polymer (FRP) bridge decks have been increasingly used as a competitive alternative for wood, concrete and orthotropic steel decks, due to their various advantages: light-weight, good corrosion resistance, low maintenance cost and rapid installation for minimizing the traffic disturbing time. These advantages meet critical needs for rehabilitation and new construction of pedestrian and highway bridges. To be cost effective, FRP decks are usually supported by steel girders. For the connection between FRP decks and steel girders, adhesive bonding technique is usually considered as a preferable connecting method, which can reduce construction time, save weight by eliminating fasteners, allow more uniform load transfer, achieve better adaption to the brittle and anisotropic nature of FRP materials and provide higher joint efficiency. Despite the fact that FRP bridge decks and adhesive joints are already in service in many FRP-steel composite bridges, mechanical behaviour and long-term performance are still not clearly understood, which results in more conservative designs of the FRP-steel composite bridges. To compensate this lack, the overall aim of this project is to investigate mechanical behaviours (in terms of strength and stiffness) of adhesively-bonded joints between FRP bridge decks and steel girders, as well as durability of these adhesively-bonded joints. As to the first aspect, considering the distribution of traffic loads in the longitudinal and transverse directions of bridges, the adhesive-bonded joints have been experimentally studied under six loading conditions, including tensile loading, shear loading and four combining ratios of tensile and shear loading. A specific tensile-shear loading device was designed and then employed to offer six different angle loading conditions. Different surface pretreatment methods (acetone (AC), sand paper (SP) and sand blasting (SB)) were compared with regard to influences on the stiffness, load-bearing capacity, failure mode and interfacial bonding quality of adhesive joints. A Finite Element (FE) model was developed to simulate the stress distribution throughout the adhesive joints under different loading conditions, which proved that the failure of joints was induced by combination of both tensile and shear stress peaks. The edge zone (approximately 10mm from the ends of the adhesive layer) was the most sensitive area to initiate the failure, where both the shear stress peak and the tensile stress singularity were located. Another critical aspect of this research is to characterize the durability of FRP-to-steel adhesively-bonded joints under both temperature and moisture effects. The influence of hydrothermal environmental aging on the mechanical behaviours of adhesive joints has been studied and compared with the un-aged adhesive joints. The shear-tensile failure criterions of hydrothermal aged and un-aged adhesive joints were addressed. To better understand the moisture effects, the moisture diffusion process in FRP composite materials was characterized. Subsequently, the hydrothermal degradation on the flexural and interlaminar properties of FRP laminates was addressed. A coupled hygro-mechanical FE model was developed to analyse the enviroment-dependent mechanical behaviours of FRP lanimates. This FE model was first validated by test results of flexural tests and subsequently employed in an inverse parameter identification method to determine the elastic interlaminar shear modulus of FRP laminates. Predictive equations for environment-dependent mechanical properties (flexural and interlaminar) of FRP laminates were sustained by using the least square method for the curve fitting. Results of this research can contribute to the development of a design code of FRP-steel composite bridges. They can also be used as a reference information for understanding mechanical behaviours and durability of FRP-to-steel adhesively bonded joints for other applications in civil engineering field, such as strengthening of steel structures using FRP composite materials.Structural EngineeringCivil Engineering and Geoscience
Temperatuursontwikkeling in het stalen dek van een orthotrope brugdekconstructie tijdens asfalteringswerkzaamheden
No full textCivil Engineering and GeosciencesStructural Engineerin
Invloed van de stijfheid van de hoekverbinding op het vervormingsgedrag en de sterkte van een ongeschoord raamwerk
No full textCivil Engineering and GeosciencesStructural Engineerin
Fatigue classification of welded joints in orthotropic steel bridge decks
No full textThis dissertation presents the research into fatigue classifications of welded joints in orthotropic steel bridge decks. These classifications are needed to calculate the fatigue life of these joints and should be included in the design codes. For years bridge design was mainly based on static loading. Due to the development of modern light weight steel structures and extremely increasing traffic loading fatigue design becomes more and more important. A review of all available data on orthotropic decks and related fatigue test results is included. The majority of the full scale fatigue testing on orthotropic decks has been carried out by members of a European Working Group. The statistical analysis procedure used to derive the weld classes for Eurocode 3 is used to place all of the main joints in the appropriate class, and to rank different designs of each joint. In addition, recommendations are made for both good joint design and those to be avoided. The composite action between the steel deck plate and the surfacing on orthotropic decks is an important aspect of the performance, in particular because the stifness of the combined unit helps to reduce strains in the welded structure as well as in the surfacing, which results in a longer lifetime. Numerical as well as experimental analysis of the stress reduction is reported. Furthermore this dissertation highlights site measurements on existing bridges and shows the development of different wearing course systems.Civil Engineering and Geoscience
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