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1
Quesada, Díaz Raquel. "Horseshoe Bending Machine : Bending Mechanism." Thesis, Högskolan i Skövde, Institutionen för teknik och samhälle, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-9432.
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Horseshoes are manufactured metal plates developed in an extensive assortment of materials and shapes and their main function is to protect the horse’s hooves and legs against abrasion and rupture. After a certain period of time the horseshoes are lost, worn out, or the hoof needs to be treated. Horseshoeing is a repetitive time consuming process for the farrier who has to heat the horseshoe inside a forge until it reaches the required temperature and shape it with a hammer until it fits perfectly to the horses’ hoof. The main goal of this project is to develop a horseshoe bending machine able to shape the horseshoe so its shape fits perfectly the horse’s hoof. The calculation of the bending force needed to be applied to the horseshoe in order to provoke a plastic deformation will be done with Euler-Bernoulli beam theory. The bending force is then used to design and dimension each element of the bending mechanism so that it may be able to resist the stresses and prevent the parts from collapsing during its working life span. A study of the springback effect will be done followed by the analysis of the hertzian contact stresses between the rollers and the horseshoe. In addition, a clamping system is selected to constrain the movements of the horseshoe during the bending process. This machine will reduce the final user’s horse maintenance costs at the same time that makes the fitting process easier and less demanding, which will improve the farrier’s working life span and quality.
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Rafehi, Mariam. "Bending Educational Reality." VCU Scholars Compass, 2019. https://scholarscompass.vcu.edu/etd/5924.
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Virtual reality (VR), an emergent technology, affords experiential content delivery in education by evoking emotive responses in users, which can be prohibitive via traditional media. This thesis explores VR for the development of grit – passion and perseverance, which are essential characteristics in education and long-term success. The research proposes design strategies to stimulate senses for emotional engagement and a physiological response. In the project, two interactive environments position the user in emotional states to build passion and perseverance. To develop passion, the virtual world is designed to engage in creativity using 3D-spatial audio and visual effects. In contrast, to build perseverance users are exposed to a challenging environment that requires them to overcome and positively associate frustration with growth. This thesis demonstrates the potential of design for higher sense-stimulation applied through VR in education.
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Palecanda, Krishna Suraj Appachu. "Analysis and prediction of springback – 3 point bending and U-bending." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1440153425.
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Toor, A. P. S. "Biaxial cyclic plastic bending." Thesis, Coventry University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372393.
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Foussekis, Michael. "Band Bending in GaN." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1781.
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Steady-state and transient surface photovoltages in undoped GaN are studied in various environments (air, nitrogen, oxygen, vacuum) at room temperature and 400 K with a Kelvin probe attached to an optical cryostat. The results are explained within a phenomenological model accounting for the accumulation of photo-generated holes at the surface, capture of free electrons from the bulk over the near-surface potential barrier, and emission of electrons from surface states into the bulk. Mechanisms of surface photovoltage are discussed in detail. Photoadsorption and photodesorption of negatively charged species will either increase or decrease the surface potential and thus band bending. Oxygen is the assumed species responsible for the SPV changes in air ambient during continuous UV illumination. This variation in SPV will be confirmed with photoluminescence measurements.
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Poljak, Peter. "Průzkum a definice mezních parametrů ohybu u stabilizačních tyčí automobilu." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2013. http://www.nusl.cz/ntk/nusl-230518.
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Submitted master’s thesis deals with rotary draw bending of tubes as a subprocess of automobile’s stabilizer bar production. The main goal of the thesis is to clarify the influence of the process parameters of the bend on the resulting shape and properties of the product. Submitted thesis includes theoretical description of the chosen tube bending technology, description of defects and possibilities of their removal. The description of the bending machine used for stabilizer bars production is done afterwards. Practical part of the thesis includes experiments clarifying influence of parameters on the resulting shape of the stabilizer bar.
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Raheem, Hassan Hassan [Verfasser]. "Plasto-Mechanical Model of Tube Bending in Rotary Draw Bending Process / Hassan Raheem Hassan." Aachen : Shaker, 2017. http://d-nb.info/1138178209/34.
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He, Yuxiang Carleton University Dissertation Engineering Civil. "Interactive design of flexural steel members subjected to bending, and combined bending and torsion." Ottawa, 1993.
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Du, Peloux De Saint Romain Lionel. "Modeling of bending-torsion couplings in active-bending structures : application to the design of elastic gridshells." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1209/document.
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Les structures de type gridshell élastique permettent de réaliser des enveloppes courbes par la déformation réversible d’une grille structurelle régulière initialement plane. Cette capacité à “former la forme” de façon efficiente prend tout son sens dans le contexte actuel où, d’une part la forme s’impose comme une composante prédominante de l’architecture moderne, et d’autre partl’enveloppe s’affirme comme le lieu névralgique de la performance des bâtiments. Fruit des recherches de l’architecte et ingénieur allemand Frei Otto dans les années 1960, elles ont été rendues populaires par la construction de la Multihalle de Mannheim en 1975. Cependant, en dépit de leur potentiel, très peu de projets de ce type ont vu le jour suite à cette réalisation emblématique qui en a pourtant démontré la faisabilité à grande échelle. Et pour cause, les moyens engagés à l’époque ne sauraient assurer la reproductibilité de cette expérience dans un contexte plus classique de projet, notamment sur le plan économique. Par ailleurs, les techniques et les méthodes développées alors sont pour la plus part tombées en désuétude ou reposent sur des disciplines scientifiques qui ont considérablement évoluées. Des matériaux nouveaux, composites, ont vu le jour. Ils repoussent les limitations intrinsèques des matériaux usuels tel que le bois et offrent des performances techniques bien plus intéressantes pour ce type d’application. Enfin, notons que le cadre réglementaire a lui aussi profondément muté, apportant une certaine rigidité vis-à-vis de la pénétration des innovations. Ainsi la conception des gridshells se pose-t-elle en des termes nouveaux aux architectes et ingénieurs actuels et se heurte à l’inadéquation des outils et méthodes existant. Dans cette thèse, qui marque une étape importante dans une aventure de recherche personnelle initiée en 2010, nous tentons d’embrasser la question de la conception des gridshells élastiques dans toute sa complexité, en abordant aussi bien les aspects théoriques que techniques et constructifs. Dans une première partie, nous livrons une revue approfondie de cette thématique et nous présentons de façon détaillée l’une de nos principales réalisation, la cathédrale éphémère de Créteil, construite en 2013 et toujours en service. Dans une seconde partie, nous développons un élément de poutre discret original avec un nombre minimal de degrés de liberté adapté à la modélisation de la flexion et de la torsion dans les gridshells constitués de poutres de section anisotrope. Enrichi d’un noeud fantôme, il permet de modéliser plus finement les phénomènes physiques au niveau des connexions et des appuis. Son implémentation numérique est présentée et validée sur quelques cas tests. Bien que cet élément ait été développé spécifiquement pour l’étude des gridshells élastiques, il pourra avantageusement être utilisé dans tout type de problème où la nécessité d’un calcul interactif avec des tiges élastiques prenant en compte les couplages flexion-torsion s’avère nécessaireAn elastic gridshell is a freeform structure, generally doubly curved, but formed out through the reversible deformation of a regular an initially flat structural grid. Building curved shapes that way seems to offer the best of both worlds : shell structures are amongst the most performant mechanically speaking while planar and orthogonal constructions are much more efficient and economic to produce than curved ones. This ability to “form a form” efficiently is of peculiar importance in the current context where morphology is a predominant component of modern architecture, and envelopes appear to be the neuralgic point for building performances. The concept was invented by Frei Otto, a German architect and structural engineer who devoted many years of research to gridshells. In 1975 he designed the Multihalle of Mannheim, a 7500 m2 wooden shell which demonstrated the feasibility of this technology and made it famous to a wide audience. However, despite their potential, very few projects of this kind were built after this major realization. And for good reason, the ressources committed at that time cannot guarantee the replicability of this experiment for more standard projects, especially on the economic level. Moreover, the technics and methods developed by Otto’s team in the 1960s have mostly fall into disuse or are based on disciplines that have considerably evolved. New materials, such as composite materials, have recently emerged. They go beyond the limitations of conventional materials such as timber and offer at all levels much better technical performances for this kind of application. Finally, it should be noted that the regulatory framework has also deeply changed, bringing a certain rigidity to the penetration of innovations in the building industry. Therefore, the design of gridshells arises in new terms for current architects and engineers and comes up against the inadequacy of existing tools and methods. In this thesis, which marks an important step in a personal research adventure initiated in 2010, we try to embrace the issue of the design of elastic gridshells in all its complexity, addressing both theoretical, technical and constructive aspects. In a first part, we deliver a thorough review of this topic and we present in detail one of our main achievements, the ephemeral cathedral of Créteil, built in 2013 and still in service. In a second part, we develop an original discrete beam element with a minimal number of degrees of freedom adapted to the modeling of bending and torsion inside gridshell members with anisotropic cross-section. Enriched with a ghost node, it allows to model more accurately physical phenomena that occur at connections or at supports. Its numerical implementation is presented and validated through several test cases. Although this element has been developed specifically for the study of elastic gridshells, it can advantageously be used in any type of problem where the need for an interactive computation with elastic rods taking into account flexion-torsion couplings is required
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Köseoğlu, Seda, and Hasan Parlak. "Capacity calculator of rotary draw tube bending." Thesis, Linnéuniversitetet, Institutionen för teknik, TEK, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-19807.
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Plastic deformation of tubes can be achieved in numerous ways. One of the most useful type is CNC tube bending machines which is used in many industries such as aerospace, automotive, HVAC systems and so on. It is important that all components of system should mate properly after producing and because of this bend shaping requires sensitive operation on each components to ensure regularity of production processes with high quality end-product. Thus, the CNC tube bending industry to become widespread. However it brings some troubleshooting like wrinkling, springback, breakage and ovalisation. This failures depends on geometry of the material such as bending radius, tube thickness and also friction factor between dies and the tube. Effects of all parameters should be examined before generating the theory for a best solution. Therefore, prediction of the required moment for the proper bending process with low cost and shortened production time is needed. All of these requirements can be achieved through a C++ form application program.
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Jaiani, George V. "Bending of an orthotropic cusped plate." Universität Potsdam, 1998. http://opus.kobv.de/ubp/volltexte/2008/2535/.
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The bending of an orthotropic cusped plate in energetic and weighted Sobolev spaces has been considered. The existence and uniqueness of generalized and weak solutions of admissible boundary value problems (BVPs) have been investigated.
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Ridge, I. M. L. "Bending-tension fatigue of wire rope." Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315486.
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Park, Jong-Chan. "Bending collapse behaviourof top-hat tubes." Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398576.
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Murry, Robert Lester. "Continuum electrostatic analysis of DNA bending." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/38837.
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Shyu, Rong-Juin. "Bending vibration of rotating drill strings." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/14205.
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Wood, Harrison Grant. "Bending and warpage of elastic plates." Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/90576.
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This thesis presents two studies on elastic plates. In the first study, we discuss the choice of elastic energies for thin plates and shells, an unsettled issue with consequences for much recent modeling of soft matter. Through consideration of simple deformations of a thin body in the plane, we demonstrate that four bulk isotropic quadratic elastic theories have fundamentally different predictions with regard to bending behavior. At finite thickness, these qualitative effects persist near the limit of mid-surface isometry, and not all theories predict an isometric ground state. We discuss how certain kinematic measures that arose in early studies of rod mechanics lead to coherent definitions of stretching and bending, and promote the adoption of these quantities in the development of a covariant theory based on stretches rather than metrics.
In the second work, the effects of in-plane swelling gradients on thin, anisotropic plates are investigated. We study systems with a separation of scales between bending energy terms. Warped equilibrium shapes are described by two parameters controlling the spatial "rolling up'' and twisting of the surface. Shapes within this two-parameter space are explored, and it is shown that shapes will either be axisymmetric or twisted depending on swelling function parameters and material anisotropy. In some axisymmetric shapes, pitchfork bifurcations to twisted solutions are observed by varying these parameters. We also show that a familiar soft mode of the catenoid to helicoid transformation of an isotropic material no longer exists with material anisotropy.Master of Science
This thesis presents two studies on the subject of thin, elastic bodies, otherwise known as plates. Plate theory has important applications in many areas of life, ranging from the design and construction of civil structures to the mechanics of wrinkling sheets. In the first work, we discuss how different elastic plate theories have qualitatively different predictions on how a plate will behave when bent. We discuss the different physical implications of each model, and relate our findings to previous studies. Additionally, we promote the use of certain technical measures in the study of plates corresponding to the most coherent definitions of bending and stretching. In the second work, we study the effects of in-plane swelling gradients on elastic plates whose material stiffnesses vary with direction. Inspired by wood panels that warp when exposed to moisture, we model elastic plates exposed to various swelling patterns and determine the resulting warped shapes. We find that some shapes are axisymmetric, while others prefer to twist when exposed to moisture-induced swelling. By varying certain parameters of the swelling functions, or by increasing the material fiber stiffness, we also find a qualitative change in shape from an axisymmetric to a twisted surface.
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Liberles, David Alan Dervan Peter B. "Sequence specific DNA recognition and bending /." Diss., Pasadena, Calif. : California Institute of Technology, 1998. http://resolver.caltech.edu/CaltechETD:etd-04272006-155123.
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Lahey, Timothy. "Modelling Hysteresis in the Bending of Fabrics." Thesis, University of Waterloo, 2002. http://hdl.handle.net/10012/941.
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This thesis presents a model of fabric bending hysteresis. The hysteresis model is designed to reproduce the fabric bending measurements taken by the Kawabata Evaluation System (KES) and the model parameters can be derived directly from these property measurements. The advantage to using this technique is that it provides the ability to simulate a continuum of property curves. Results of the model and its components are compared and constrasted with experimental results for fabrics composed of different weaves and yarn types. An attempt to incorporate the bending model as part of a fabric drape simulation is also made.
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Dorosh, Mark Norman. "Damage growth in bending of composite beams." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28376.
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A study has been made of glass fibre reinforced plastic beams in three-point bending. In recent years, the importance of flexural loading in composites has manifested itself in the form of composite leaf springs, helicopter rotors, and other applications. This study is directed at the initiation, growth, characterization and measurement of damage in unidirectional and cross-ply composite beams.
Beams were tested in three-point static and cyclic bending. Following damage initiation, either by a machined notch or by repeated cycling, damage growth has been characterized by two damage parameters: a damage depth encompassing a number of broken fibres on the tensile surface at the central load point, and a damage length or delamination parallel to the beam longitudinal axis.
A model was developed to predict the compliance, or deflection under applied load, as a function of beam properties and damage dimensions. The model is able to predict the compliance of damaged beams with reasonable accuracy. From fracture mechanics concepts it is shown that the two damage dimensions, depth and length, are related. It is concluded that the increase in compliance, a result of the growing damage dimensions, is related to the growth of the damage depth; the damage length follows from the relation between damage parameters and the compliance follows from the compliance model.
The damage state can thus be determined by compliance measurements if the relevant material properties and loading conditions are known. However, in service, compliance measurements may not be practical. Therefore a section of this study is devoted to an alternative damage measurement technique, namely acoustic emission monitoring. Damage initiation, compliance, damage length and damage depth were measured with AE monitoring techniques.Applied Science, Faculty of
Materials Engineering, Department of
Graduate
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Nguyen, Vinhson Ba. "Finite-element simulation of ram pipe bending." Thesis, University of Ottawa (Canada), 1988. http://hdl.handle.net/10393/5265.
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Lazim, Duraid. "Springback in draw-bending on aerospace alloys." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79244.
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The springback phenomenon was studied by a series of draw-bend tests. These tests were done by varying the blankholding pressure with different lubrication conditions, and with different transverse anisotropy directions. The purpose is to find the forming loads, the thickness changes and the springback angles. It has been found that the springback angle after unloading depends on the amount of blankholding pressure, the material properties, and the tool geometry. Increasing the blankholding pressure almost eliminates the springback if the tensile stress caused by the blankholding pressure reaches the yield in the material. To compliment the experiments, a theoretical model has been developed by calculating the tensile strain developed from applying the blankholding pressure. This strain then was considered in finding the total bending moment.
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Chen, Shiming. "Instability of composite beams in hogging bending." Thesis, University of Warwick, 1992. http://wrap.warwick.ac.uk/4009/.
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This work is concerned with local buckling and lateral distortional buckling, two aspects of instability that govern the design of composite beams in hogging regions. Local buckling in hogging regions of a continuous composite beam was modelled by moment curvature characteristics of a cantilever, modified by two curvature ratios, K1 and K2. Test based expressions for K1 and K2, in terms of a combined slenderness λc, were developed, and subsequently used in numerical analyses of 50 two-span composite beams to assess moment redistribution allowed for Class 2 beams by draft Eurocode 4. The analyses include effects of non-linear material properties, residual stresses and local buckling. The parametrical studies include adverse values, in relation to practice, of relative length of adjacent spans, span-to-depth ratio, and ratio of hogging to sagging moment of resistances. It is concluded that the redistribution of elastic bending moments allowed by the draft Eurocode 4 is safe and economical. Distortional lateral buckling of composite beams with both continuous and discrete U-frame actions was studied experimentally. Distortional lateral buckling was found in the tests of two composite beams with inverted U-frame actions. Web distortion was effectively reduced by vertical web stiffeners, which form a part of discrete U-frames together with the slab and the connection of U-frame. The work provides background to assess lateral buckling strength for composite beams with both continuous and discrete U-frame actions. A further theoretical approach on the topic of discrete inverted U-frame action was presented. Strength and stiffness of discrete U-frame connections were also studied. The strength of a discrete U-frame connection was found to be influenced by both the shear failure of concrete, and the yielding of steel top flange in the connection. A simple rule to assure strength of U-frame connections is proposed by checking these two failures separately. The prediction of shear failure of a U-frame connection is based on a truss model, and the prediction of failure in the steel top flange is based on a rigid plastic mechanism. A semi-empirical formula for flexibility of a U-frame connection was derived. They were all checked against test results. Interactive U-frame force and U-frame stiffness were also studied. A tentative design method for discrete U-frame composite beams was proposed.
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Kaczmarek, Adam S. "Sensing bending in a compliant biomimetic fish." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/36753.
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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.Includes bibliographical references (p. 34).
This thesis examines the problem of sensing motion in a compliant biomimetic device. Specifically, it will examine the motion of a tail in a biomimetic fish. To date, the fish has been an open-loop system, the motion of the tail only controlled by the input to a servo motor. By sensing the motion of the tail, a closed loop system can be implemented to control the motion. In order to determine the best sensor to use, a number of options were examined. We decided to use foil bend sensors. The silicone used in the prototype was too compliant and therefore the sensors did not bend at a magnitude great enough to provide sufficient information about the bending of the tail. Upon further development and use of the sensors in stiffer silicones, they could be used in a closed loop system.
by Adam S. Kaczmarek.
S.B.
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Chun, Lap Ming Leo. "Bending loss of polarization maintaining optical fiber." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/40189.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (leaves 56-57).
by Lap Ming Leo Chun.
M.Eng.
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Derian, Edward J. "Large deformation dynamic bending of composite beams." Thesis, Virginia Tech, 1985. http://hdl.handle.net/10919/45678.
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The large deformation response of composite beams subjected to a
dynamic axial load was studied. The beams were loaded with a moderate
amount of eccentricity to promote bending. The study was primarily
experimental but some finite element results were obtained. Both the
deformation and the failure of the beams were of interest. The static
response of the beams was also studied in order to determine the
difference between the static and dynamic failure. Twelve different
laminate types were tested. The beams tested were 23 in. by 2 in. and
generally 30 plies thick. The beams were loaded dynamically with a
gravity-driven impactor traveling at 19.6 ft./sec. and quasi-static
tests were done on identical beams in a displacement controlled
manner. For laminates of practical interest, the failure modes under
static and dynamic loadings were identical. Failure in most of the
laminate types occurred in a single event involving 40% to 50% of the
plies. However, failure in laminates with 30° or 15° off axis plies occurred in several events. All laminates exhibited bimodular
properties. The compressive flexural moduli in some laminates was
measured to be 1/2 the tensile flexural modulus. No simple relationship
could be found among the measured ultimate failure strains of the
different laminate types. Using empirically determined flexural
properties, a finite element analysis was reasonably accurate in
predicting the static and dynamic deformation response.Master of Science
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Gantner, Peter. "The Characterisation of the Free-Bending Technique." Thesis, Glasgow Caledonian University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.486486.
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The increasing requirements in the automotive industry regarding safety, weight and economic efficiency involve the application of stiff structures made from hollow sections, manufactured by bending tubes and profiles into complex shapes. These geometries comprise different radii in several planes, including compound bends, and demand new techniques for manufacture. To this end, the free-bending technique has evolved which has the potential to realise almost arbitrary bending geometries combined with fast bending speed. This research provides a general insight' into free-bending and investigates the possibilities of this novel bending technique in respect to applications in the automotive industry. The principles of the free-bending technique are explained and a comparison is drawn with other bending techniques. The Nissin CNC Bender was used to carry out the bending tests in order to investigate the free-bending technique with regard to its geometrical capabilities, bending speed, surface quality and the resulting ovality of the tube after bending. For this a try-out geometry similar to an engine cradle was bent using steel, stainless steel and aluminium tubes and the repeat accuracy was examined. For feasibility studies, a FEA model was developed and validated with the results from the tubes bent from a second bending test series where the geometrical results including wall thickness and ovality were investigated. From this FEA model the elastic and plastic forming ofthe tube during the process was examined. In order to determine the necessary bending control data for arbitrary bending geometries, an analytical model based on the geometrical data (bending line and tool set-up) was derived. Finally a third test series with rectangular aluminium profiles was carried out and the profiles' geometries, the wall thicknesses and the strains were evaluated and compared with the FEA results. The free-bending technique has proven its potential to realise almost any arbitrary bending geometry with a bending ratio of the centre line radius with respect to the initial tube diameter of2.1 using a ball mandrel. Free-bending has the added advantage in achieving compound bends without the recourse to special tools or tool changes for different bending radii. Furthermore, the improvement of up to 100 %in bending speed compared to rotary draw bending can be achieved dependent on the composition of bends in the geometry. However, due to its sensitivity to changes in material behaviour, lubrication or geometrical tolerances, it is necessary to have stringent control for parts with small bending tolerances. This research has contributed to new knowledge with regard to the possibilities and limitations of the free-bending technique and serves as a decision aid for the application ofthis novel technique in series automotive production. Furthermore, the FEA model in conjunction with the analytical model to determine the process control data enables the evaluation and the realisation offeasibility for any required bending geometry before the production ofexpensive bending tools.
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Binazir, Ali. "Pure Bending of Pipe-in-Pipe systems." Thesis, Griffith University, 2020. http://hdl.handle.net/10072/398087.
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Due to the recent raise of oil price, giant oil and gas companies have expanded their exploration to more than 3 kilometres under see level. In extreme conditions of deep under water excavation, pipe-in-pipe systems have become favourable option due to their unique structural capacity. Subsea pipelines and PIP systems experience large bending moments during installation and operation. However, unlike single-walled pipelines, the behaviour of PIPs under bending has been only marginally addressed. In this project, the bending response of the PIP systems with diameter-to-thickness ratio (D/t) of 15 to 40 is investigated. To this purpose Linear bifurcation analyses (LBA) and geometrically nonlinear analyses (GNA) are conducted on PIPs of varying lengths. For the first time, closed formed analytical solution are derived and provided to predict the classical and nonlinear limit moments of PIPs, and are compared to the existing expressions for single-walled pipelines. Ultimate bending moments of PIPs are obtained from physical four-point bending tests and are compared against geometrically and materially nonlinear analyses (GMNA). The finite element results show that in PIPs with centralizers, the limit moments (GNA) drop slightly, however, the ultimate moments (GMNA) remain unchanged. A parametric study of the effect of geometry and material properties of the inner and outer pipes on the ultimate moment of PIPs is presented. It is understood that the ultimate moments of PIPs with thick tubes are predominantly influenced by the material nonlinearities rather than ovalization of the tubes. Moreover, to investigate effect of external pressure on the bending moment capacity of PIPs, Finite Element study has been performed on a PIP system subject to pure bending, pure external pressure and combined actions of external pressure and bending. Results show that bending moment capacity of the PIP systems are more susceptible to the external pressure compared to that of the same single outer pipes.Thesis (Masters)
Master of Philosophy (MPhil)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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Garbin, F., F. Garbin, A. Levano, and R. Arciniega. "Bending Analysis of Nonlocal Functionally Graded Beams." Institute of Physics Publishing, 2020. http://hdl.handle.net/10757/651836.
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In this paper, we study the nonlocal linear bending behavior of functionally graded beams subjected to distributed loads. A finite element formulation for an improved first-order shear deformation theory for beams with five independent variables is proposed. The formulation takes into consideration 3D constitutive equations. Eringen's nonlocal differential model is used to rewrite the nonlocal stress resultants in terms of displacements. The finite element formulation is derived by means of the principle of virtual work. High-order nodal-spectral interpolation functions were utilized to approximate the field variables, which minimizes the locking problem. Numerical results and comparisons of the present formulation with those found in the literature for typical benchmark problems involving nonlocal beams are found to be satisfactory and show the validity of the developed finite element model.
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Nivarti, Girish Venkata. "The bending effect in turbulent flame propagation." Thesis, University of Cambridge, 2017. https://www.repository.cam.ac.uk/handle/1810/270335.
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In the present thesis, the sensitivity of flame propagation to the turbulent motion of burning gases is investigated. The long-standing issue of the 'bending effect' is focused upon, which refers to the experimentally-observed inhibition of flame propagation velocity at high intensities of turbulence. Plausible mechanisms for the bending effect are investigated by isolating systematically the effects of turbulence intensity. By providing a novel perspective on this topic, the thesis addresses the fundamental limits of turbulent burning. The investigation employs Direct Numerical Simulation (DNS), which enables the basic conditions of burning to be controlled directly. A parametric DNS dataset is designed and generated by increasing turbulence intensity over five separate simulations. Effects of turbulent motion are isolated in this manner, such that the bending effect is reproduced in the variation of flame propagation velocity recorded. Subsequently, the validity of Damköhler's hypotheses is investigated to ascertain the mechanism of bending. Analysis of the DNS dataset highlights the significance of kinematic flame response in determining turbulent flame propagation. Damköhler's first hypothesis is found to be valid throughout the dataset, suggesting that the bending effect may be a consequence of self-regulation of the flame surface. This contradicts the dominant belief that bending occurs as a result of flame surface disruption by the action of turbulence. Damköhler's second hypothesis is found to be valid in a relatively limited regime within the dataset, its validity governed by flame-induced effects on the prescribed turbulent flow field. Therefore, this thesis presents turbulent flame propagation and the bending effect as emergent from the dynamics of a flame surface that retains its internal thermo-chemical structure. Finally, experimental validation is sought for the proposed mechanisms of bending. Comparisons have been initiated with measurements in the Leeds explosion vessel, based on which the widely accepted mechanism of bending was hypothesized twenty-five years ago. Modifications to the DNS framework warranted by this comparison have aided the development of novel computationally-efficient algorithms. The ongoing work may yield insights into the key mechanism of the bending effect in turbulent flame propagation.
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Bean, Matthew James. "Bending fatigue performance of small-scale stay cables." Full-text Adobe Acrobat (PDF) file, 2006. http://www.engr.utexas.edu/research/fsel/FSEL_reports/Thesis/Bean,%20Matthew.pdf.
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Wolf, Kai-Dietrich. "Electromechanical energy conversion in asymmetric piezoelectric bending actuators." [S.l. : s.n.], 2000. http://elib.tu-darmstadt.de/diss/000094/d.pdf.
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Agarwal, Rohit. "Tube bending with axial pull and internal pressure." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/442.
Full textAbstract:
Tube bending is a widely used manufacturing process in the aerospace, automotive, and other industries. During tube bending, considerable in-plane distortion and thickness variation occurs. The thickness increases at the intrados (surface of tube in contact with the die) and it reduces at the extrados (outer surface of the tube). In some cases, when the bend die radius is small, wrinkling occurs at the intrados. In industry a mandrel is used to eliminate wrinkling and reduce distortion. However, in the case of a close bend die radius, use of a mandrel should be avoided as bending with the mandrel increases the thinning of the wall at the extrados, which is undesirable in the manufacturing operation. The present research focuses on additional loadings such as axial force and internal pressure which can be used to achieve better shape control and thickness distribution of the tube. Based on plasticity theories, an analytical model is developed to predict cross section distortion and thickness change of tubes under various loading conditions. Results from both the FEA and analytical model indicated that at the intrados the increase in thickness for bending with internal pressure and bending with combined axial pull and internal pressure was nearly the same. But in the case of bending with the combination of axial pull and internal pressure there was a significant reduction of thickness at the extrados. A parametric study was conducted for the case of bending with combined internal pressure and axial pull and it was seen that with proper selection of the pressure and axial pull wrinkling can be eliminated, thickness distribution around the tube can be optimized, and cross section distortion of the tube can be reduced. Predictions of the analytical model are in good agreement with finite element simulations and published experimental results. The model can be used to evaluate tooling and process design in tube bending.
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Liu, Xing Lu. "Some problems and analysis for thermal bending plates." Thesis, University of Macau, 2010. http://umaclib3.umac.mo/record=b2148242.
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Christian, Lee Conner. "Thru-thickness bending stress distribution at elevated temperatures." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2315.
Full textAbstract:
During the bending of flange plate used for dapped girders some highway bridge
fabricators are experiencing cracking of the flange plate particularly when heat is used in
assisting the bending process. Due to the extreme strains experienced during the
fabrication process, investigating this problem requires the use of a finite element
analysis. The fabrication process was broken down into two parts, first the heating of
the plate through the use of either a furnace or an acetylene torch (thermal), and the
second was the bending process (structural). The five different temperatures collected
during the thermal analysis were a uniform temperature of 75oF, a 1100oF uniform
temperature as a result of furnace heating, both five and ten minutes of air-cooling after
the plate had reached a uniform temperature of 1100oF, and the temperature gradient
after heating the flange plate to a surface temperature of 1200oF though the use of an
acetylene torch. After the thermal analysis was completed, the resulting temperatures
were imported into the structural model. The plate thicknesses analyzed were one, one
and a half, and two inches, assuming both 50 and 70 ksi yield strengths. To achieve a 90
degree six-inch radius bend the plate was bent in five separate locations. The result of
this analysis showed that with the introduction of temperature gradients into thefabrication process, the strains along the plate??s extreme fibers increased. The model
further showed that for both a one and a half and two-inch thick plate the extreme fiber
strains exceeded ten percent, which further adds to the increased risk of the flange plate
cracking during fabrication. The highest residual stresses through the plate??s thickness
occurred during cold bending. The residual stresses through the plate??s thickness
decreased when the fabrication process was carried out at elevated temperatures. When
steel exceeds a strain of 10 to 16 percent during the fabrication process, the plate
becomes susceptible to cracking. This strain limit was exceeded for plate thicknesses of
one and a half and two inches.
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Nordblad, Erik. "Opening New Radio Windows and Bending Twisted Beams." Doctoral thesis, Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-158797.
Full textAbstract:
In ground based high frequency (HF) radio pumping experiments, absorption of ordinary (O) mode pump waves energises the ionospheric plasma, producing optical emissions and other effects. Pump-induced or natural kilometre-scale field-aligned density depletions are believed to play a role in self-focussing phenomena such as the magnetic zenith (MZ) effect, i.e., the increased plasma response observed in the direction of Earth's magnetic field. Using ray tracing, we study the propagation of ordinary (O) mode HF radio waves in an ionosphere modified by density depletions, with special attention to transmission through the radio window (RW), where O mode waves convert into the extraordinary (X, or Z) mode. The depletions are shown to shift the position of the RW, or to introduce RWs at new locations. In a simplified model neglecting absorption, we estimate the wave electric field strength perpendicular to the magnetic field at altitudes normally inaccessible. This field could excite upper hybrid waves on small scale density perturbations. We also show how transmission and focussing combine to give stronger fields in some directions, notably at angles close to the MZ, with possible implications for the MZ effect. In a separate study, we consider electromagnetic (e-m) beams with helical wavefronts (i.e., twisted beams), which are associated with orbital angular momentum (OAM). By applying geometrical optics to each plane wave component of a twisted nonparaxial e-m Bessel beam, we calculate analytically the shift of the beam's centre of gravity during propagation perpendicularly and obliquely to a weak refractive index gradient in an isotropic medium. In addition to the so-called Hall shifts expected from paraxial theory, the nonparaxial treatment reveals new shifts in both the transverse and lateral directions. In some situations, the new shifts should be significant also for nearly paraxial beams.
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Blount, Maurice John. "Bending and buckling of a falling viscous thread." Thesis, University of Cambridge, 2010. https://www.repository.cam.ac.uk/handle/1810/252208.
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Wilson, Jean-Marie J. "Lower limb muscle function during deep-knee bending." Thesis, University of Ottawa (Canada), 1989. http://hdl.handle.net/10393/5589.
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Campbell, Anthony. "Bending authors & narrative straits, Shakespeare's telling strategies." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ42564.pdf.
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Chin, Helen Hau Ling. "Bending displacement capacity of elongated reinforced concrete columns." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/43491.
Full textAbstract:
The bending displacement capacity of elongated wall-like gravity-load columns subjected to lateral displacements due to earthquake demands on a high-rise building is of considerable concern. The long cross-sectional dimension makes these members much less flexible compared to square columns. Elongated gravity-load columns are popular because they can be hidden in walls and because they reduce the span of floor slabs, which means the thickness of the floor slabs can be reduced. No previous tests have been done on elongated gravity-load columns subjected to simulated earthquake loading. In the current study, five half-scale specimens including four column specimens and one wall specimen were subjected to constant axial compression and reverse cyclic lateral load to determine the displacement capacity of the members. The cross-sectional width-to-length ratios of the four columns were 1:1 (square), 1:2, 1:4, 1:8 and the wall specimen was 1:8. The load-deformation responses of the specimens were predicted using two nonlinear programs Response2000 and VecTor2, as well as hand calculation procedures. The predictions were used to design the test setup and were compared with the test results in order to better understand the significance of the test results. The predicted load capacities of all specimens were found to be similar to the observed maximum loads; but the displacement capacities of all specimens were significantly higher than predicted. Slip of the vertical reinforcing bars from the column foundations contributed to a large part of the increased displacement capacity of the columns. Only the elongated columns with a cross-sectional width-to-length ratios of 1:4 and 1:8 and the wall specimen suffered complete collapse during the test.
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Kuriakose, Sunil. "Analysis of damage in composite laminates under bending." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/12054.
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Totty, Jennifer L. "Linear cellular copper in bending, compression and shear." Thesis, Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/16913.
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任穎華 and Wing-wa Yam. "Two dimensional membrane and bending elements with defects." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31226991.
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Matar, Ali. "The mechano sorptive creep of softwood in bending." Thesis, London South Bank University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288110.
Full textAbstract:
This PhD research project mainly examined the important yet incompletely understood field of the mechano-sorptive creep of softwood. It included the acquisition of accurate creep data during constant and cyclic moisture conditions. The study only concerns the loading of softwood in the longitudinal, parallel to the grain direction in bending mode. Mechano-sorptive creep deformation takes place when the wood is subjected to load in varying humidity conditions, where the creep deformation is substantially higher than the creep deformation under constant humidity conditions. Visco-elastic creep is defined as the creep strain that is primarily dependent on time. Further analysis on the pseudo-creep, which is reversible with moisture changes, was also investigated. The Young's Modulus (E) and density (p) of the samples used in this research were measured and the ratio of (E/p) was used to characterise the quality of the wood specimen. A program was written in Quick-Basic for the computer to take readings from the creep machines at all times during all creep tests for acquiring maximum creep data possible for obtaining better results. A 'steaming' technique was implemented to accelerate creep recovery, in order to allow the re-use of the same sample for repeated creep testing, so reducing the effects of variability. Measurements of visco-elastic creep, mechano-sorptive creep limit and pseudo-creep rate as functions of percentage relative humidity and E/p were investigated and analysed. The mechano-sorptive creep limit was successfully reached by the load-reduction method. The pseudo-creep rate was similar for samples with the same values of E/p at different relative humidity. The higher the relative humidity, the larger the magnitude of visco-elastic and the 'reference' creep at the mechano-sorptive creep limit. A higher value of E/p produced lower pseudocreep rate, visco-elastic creep and mechano-sorptive creep limit. Equations were derived from the one week visco-elastic creep experimental data in order to extrapolate visco-elastic creep to longer time durations, (medium, long and permanent periods, and compared to the new European code of practice for timber design, namely the Draft Eurocode 5), and at two critical relative humidity conditions, (63% and 90%rh), which correspond to the Service Classes 1 and 2 in the Draft Eurocode 5. Also, an equation to predict the mechano-sorptive creep limit at various values of E/p for the two critical relative humidity conditions, (63% and 90%rh), was acquired. The prediction of creep at various relative humidities along the pseudo creep line was also quantified. The extrapolated visco-elastic creep along with the total upper-bound creep values were compared to the creep allowances of the Draft Eurocode 5 for both Service Classes 1 and 2. Moreover, a design scheme for estimating the upper-bound creep, consisting of the addition of visco-elastic, mechano-sorptive and pseudo creep for Draft Eurocode 5 Service Classes 1 and 2 was achieved. A study of the degree of interaction between visco-elastic and mechanosorptive creep was further investigated. Two different experiments were performed to reach some conclusion. The results of the first experiment showed that mechanosorptive creep acceleration decreases the visco-elastic creep rate and there was some kind of interaction between the two creep mechanisms. Hence the two creep mechanisms should not be considered as a separate phenomenon. On the other hand, the results of the second experiment showed that the visco-elastic and mechanosorptive creep are not a single process but are related processes. Moreover, it was deduced that the mechano-sorptive creep does not depend on the accumulation of the visco-elastic creep rate.
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Tenggren, Richard. "How bending affects the ballistic properties of Armox." Thesis, KTH, Materialvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-150887.
Full textAbstract:
This thesis discusses how bending of Armox 500T and Armox 440T affects the ballistic properties; it also discusses the bending performance of Armox 500T and Armox 440T. The purpose is to develop new bending recommendations, and to investigate the correlation between bending radius and maintaining ballistic performance and offer more reliable bending recommendations to the Armox customers. The new bending recommendations will satisfy both mechanical and ballistic performance. To achieve the purpose, bending tests was made, and then the bended specimens were used to investigate the deformation from the bending. The method hardness mapping was used to describe the deformation in the specimen, because of the lack of information of deformation mechanism in martensitic steels. To test the ballistic properties, V50-tests were made on bended specimens at Åkers Krutbruk Protection AB. The V50-value is the calculated average value from six rounds, with three stops and three penetrations in a span of 40 m/s. The result from the testing shows that the bending does not have any significantly effect on the ballistic properties on the tested combinations of materials and ammunitions. The conclusions from the testing results are that the bending does not significantly influence the ballistic properties for the tested materials and ammunitions and the bending recommendations were greatly improved.
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Thomas, Wilfred H. "Bending behaviour of OSB decking under concentrated load." Thesis, University of Surrey, 1996. http://epubs.surrey.ac.uk/647/.
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Shelton, Christopher Francis. "The mechano-sorptive creep of wood in bending." Thesis, London South Bank University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329808.
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CORBANI, SILVIA. "CRACK GROWTH WITH PARTIAL BENDING-INDUCED CRACK CLOSURE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2012. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=23847@1.
Full textAbstract:
PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROCONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
Neste trabalho são investigadas experimentalmente e numericamente as mudanças de geometria em trincas inicialmente passantes submetidas a carregamento remoto de flexão pura induzindo fechamento parcial das faces da trinca. Esse crescimento de trinca pode ocorrer numa variedade de estruturas com defeitos pré-existentes, tais como fuselagens de aviões, cascos de navios, vasos de pressões e pontes metálicas. O carregamento de flexão pura ocasiona regiões de tração e compressão na frente da trinca. É inquestionável que parte das faces da trinca sob compressão fecha independentemente de qualquer mecanismo de fechamento; e outra parte das faces da trinca, por outro lado, sob tração cresce mudando gradualmente de geometria. Após realizar ensaios em corpos-de-prova de aço ASTM A-36, foi observado que tais carregamentos geram uma quina na frente da trinca, que é a transição de uma geometria parcialmente passante e um trecho remanescente da geometria inicial. Para entender a distribuição do fator de intensidade de tensão em tais frentes de trinca, suas geometrias foram reproduzidas em um modelador tridimensional de mecânica da fratura linear elástica, o FRANC3D, acoplado a um programa de análise de elementos finitos (ABAQUS). Com este sistema acoplado, foram executadas análises considerando efeitos não lineares causados pelo contato das faces da trinca sob compressão. Verificou-se a necessidade de propor metodologias para tratamento dos resultados numéricos na quina, obtendo-se predições eficientes das mudanças na geometria da trinca. Contudo, a estimativa de vida, quando se compara taxas de crescimento da trinca obtidas em um corpo-de-prova sob tração cíclica e as taxas em um corpo-de-prova sob flexão com fechamento parcial da trinca, foi melhor reproduzida usando um fator de correção de fechamento da trinca. Adicionalmente, uma série de expressões empíricas normalizadas para geometrias da trinca e fatores de intensidade de tensão são propostas.
This work investigates experimentally and numerically how the front of initially through edge cracks in plate changes after they pass to be remotely fatigue loaded under pure bending to induce partial closure of the crack faces. This type of crack growth problem can occur in a variety of structures with preexisting defects, such as aircraft fuselages, ship hulls, pressure vessels components, and steel bridges. The bending loads induce tension and compression regions along the crack front, with the part of the crack faces that work under compression undoubtedly closed by the load, independently of any other closure mechanism. The part of the crack faces that work under tension; on the other hand, crack grows by fatigue gradually changing its shape. After performing tests on ASTM A36 steel specimens, it was observed that the bending load induces a kink on the crack front, in the transition between the part through crack created on the tension side and initial crack geometry. To understand the distribution of the stress intensity factor along such crack fronts, the measured crack shapes were reproduced in a three-dimensional fracture mechanics modeler (FRANC3D) coupled to a finite element analysis program (ABAQUS). With this coupled system, linear elastic stress analysis simulations were performed considering the nonlinear effects caused by the crack face contact in the compressed region. In particular, methods had to be proposed to treat numerical noise around the kink. The proposed methodology efficiently predicts the observed crack front shape changes; although the observed fatigue lives were better reproduced using a crackclosure correction factor when compared to crack growth data obtained from standard compact tension specimens. In addition, a series of normalized empiric expressions for both crack front shapes and stress intensity factors are proposed.
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Muragishi, Osamu 1961. "Premature cleavage of ship plating under reversed bending." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/91344.
Full textAbstract:
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, February 2001.Includes bibliographical references (p. 71-75).
The objective of the thesis is to develop and apply testing methodology for fracture initiation of actual components of a ship's hull and to provide engineering design data to be used by the industry in predicting the effects of extreme loads such as accidents at sea or earthquakes. Since cleavage is more dangerous than ductile fracture, attention was focused on conditions controlling cleavage fracture. A careful inspection of damaged components of ships and structures damaged in the 1995 Kobe earthquake showed that fracture often initiates in the zones of large bending strains. It was found from the literature that tensile strains resulting from bending alone are not sufficient to cause fracture. A certain amount of reversed strain is needed. Also, temperature is an important parameter of the process. A comprehensive experimental program was undertaken to study the effects of pre-strain, reversed strain, and temperature. A total of 39 bending specimens cut from actual ship plating were tested and on that basis a 3-D failure surface was constructed for the AH36 steel, suitable for practical applications. The failure surface was formed in terms of compressive pre-strain, temperature, and reverse tensile strain. As-rolled plates pre-strained by -0.43 at room temperature with a Charpy 20 J work transition of 6⁰ C, cleaved with very small reversed strain of 0.011 at low service temperatures of-40⁰ C. Machining the surface, as done with conventional test specimens, raised the reversed strain to cleavage to 0.33.
(cont.) Thus, a serious risk is hidden in the use of machined specimens in bending. Effects of other parameters such as aging were also studied on separate types of specimens. In addition, several mechanisms that could be responsible for the initiation of cleavage were identified and discussed in some depth. Because of the complex interaction between these various mechanisms and effects, it is not possible to make fracture prediction based on first principles. This difficulty necessitates conducting experiments on full-scale test specimens on ship plating which was one of the main objectives of the present thesis. In practical terms, the thesis gives a relatively simple method to chose a steel that could withstand anticipated accidental conditions.
by Osamu Muragishi.
Ph.D.
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Aeck, Richard Hull. "Free4orm framing : high-performance bending-active strip construction." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/111548.
Full textAbstract:
Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2017.Cataloged from PDF version of thesis. "February 2017."
Includes bibliographical references (pages 127-131).
This thesis re-thinks conventional light frame and panelized construction methodologies employed in residential and general medium-scale construction. To do so, it investigates the flexural geometry, the structural performance, and volumetric approaches to systematizing elastically bent developable strips. Many rapidly-renewable sheet materials exist or are near market, and the local availability of flatbed machining increases with each new makerspace. Thus, this thesis proposes using simple cutting and bending operations, site-applied attachments, and granulated insulation to produce permanent, freeform, stressed-skin formwork (which is herein branded "Free4orm" strip construction). Observing only partial engagement of medium-scale building applications, this project deploys elastic bending for design diversity by developing open, pre-cut, site-assembled systems for complex structural form. Initial contextual, typological, and geometric research exercises lead to an experimental installation (fiber-reinforced polymer rod and shrink-wrap), to material testing (plywood, bamboo, and phenolic paper), and then to creating computational dimensional analysis tools. Different methods of assembling (tiling, hinging, linking, networking, self-straining, wrapping, staggering etc.) and "unitizing" bending-active strips are developed, tested, and ultimately combined into a prototype, "bend-up, zip-up, iron-up," methodology. Numerical solvers and plug-ins (Strand7, Karamba, and Scan&Solve) are used for in-process analysis to inform conceptualization and to supplement theoretical predictions. Full-scale prototype "unitized, rapid-assembly" and "semiunitized, site-assembly" specimens are fabricated and experimentally loaded to evaluate theoretical stress predictions and preliminary detailing. In the closing design exercises and demonstrations, a single-module arch and a heliotropic canopy are presented. This project explores different possibilities for using flexure to create cost-aware dimensional variation in residential building systems in order to enable passive functional articulation and increase access to surface-active architecture.
by Richard Aeck.
S.M. in Architecture Studies
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Gul, Rizwan Mahmood 1967. "Bending fatigue and creep of tough matrix laminates." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/17388.
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