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1
Matthews, Mark Thurgood. "Impact of Large Gravity Loads on Buckling Restrained Braced Frame Performance." Diss., CLICK HERE for online access, 2009. http://contentdm.lib.byu.edu/ETD/image/etd3286.pdf.
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Mensah, Frederick Ayisi. "Comparison of Strength, Stiffness and Ductility of Reduced Beam Section Subjected to Lateral Loads Only and Combined Gravity And Lateral Loads." OpenSIUC, 2018. https://opensiuc.lib.siu.edu/theses/2434.
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Lateral loads from Northridge Earthquake in 1994 caused brittle fractures at column-beam connections in rigid frame structures which hitherto were thought to have high ductility to resist such brittle fractures. These brittle fractures were caused by the moment frame connections’ inability to undergo inelastic deformation which eventually resulted in several structural damages. Reduced beam section (RBS) connection was among one of the solutions proposed by researchers following the Northridge Earthquake. In RBS connections, part of the beam flanges or web at a distance from the face of the column is selectively cut off to reduce its capacity in order to induce plastic hinge away from the beam-column interface. Reducing the beam section, weakens the beam and allows the groove welds and the panel zone to have a higher strength compared to the beam, thereby achieving stronger column-weaker beam design which have a better seismic performance. RBS must provide adequate combination of stiffness, strength and ductility in order to ensure acceptable seismic performance. The scope of this study is to compare strength, ductility and stiffness of reduced beam section under lateral loads only and combined gravity and lateral loads. Four finite element models were created with all conditions kept constant except loading conditions on the frames. Results from this study indicates that all models have almost the same stiffness with the models under combined gravity and lateral loads having higher ductility and ultimate strength.
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Neubert, Michael Christopher. "Estimation of Required Restraint Forces in Z-Purlin Supported, Sloped Roofs Under Gravity Loads." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/44512.
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The current specification provisions for the prediction of lateral restraint forces in Z-purlin supported roof systems under gravity loads are in Section D3.1 of the 1996 AISI Cold-Formed Specification. The design equations contained in these provisions are empirical and based on statistical analysis. They were developed using elastic stiffness models of flat roofs and were verified by experimental testing. The provisions need refinement, because the treatment of roof slope and system effects is incorrect. Also, the current design provisions are based upon an assumed panel stiffness value, ignoring the significant difference in required restraint force that occurs when panel stiffness is varied.
Therefore, a new restraint force design procedure, having a stronger reliance on engineering principles, is proposed. This new treatment of the static forces in Z-purlin roofs led to a more accurate method of addressing roof slope. Elastic stiffness models, with varying roof slope, panel stiffness, and cross-sectional properties, were used to develop the proposed procedure. The basis of the procedure is to determine the lateral restraint force required for a single purlin system and then extend this result to systems with multiple restrained purlin lines. Roof slope is incorporated into the calculation of the single purlin restraint force, which includes eccentric gravity loads and forces induced by Z-purlin asymmetry. The procedure includes a system effect factor to account for the observed nonlinear increase in restraint force with the number of restrained purlins. An adjustment factor varies the predicted restraint force depending on the shear stiffness of the roof panel. The proposed procedure applies to five bracing configurations: support, third-point, midspan, quarter point, and third-point plus support restraints.Master of Science
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Tryfonidis, Michail. "Robust adaptive control modeling of human arm movements subject to altered gravity and mechanical loads." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/9483.
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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1999.Includes bibliographical references (leaves 159-164).
It has been observed that during orbital spaceflight the absence of gravitation related sensory inputs causes incongruence between the expected and the actual sensory feedback resulting from voluntary movements. This incongruence results in a reinterpretation or neglect of gravity-induced sensory input signals. Over time, new internal models develop, gradually compensating for the loss of spatial reference. The study of adaptation of goal-directed movements is the main focus of this thesis. The hypothesis is that during the adaptive learning process the neural connections behave in ways that can be described by an adaptive control method. The investigation presented in this thesis includes two different sets of experiments. A series of dart throwing experiments took place onboard the space station Mir. Experiments also took place at the Biomechanics lab at MIT, where the subjects performed a series of continuous trajectory tracking movements while a planar robotic manipulandum exerted external torques on the subjects' moving arms. The experimental hypothesis for both experiments is that during the first few trials the subjects will perform poorly trying to follow a prescribed trajectory, or trying to hit a target. A theoretical framework is developed that is a modification of the sliding control method used in robotics. The new control framework is an attempt to explain the adaptive behavior of the subjects. Numerical simulations of the proposed framework are compared with experimental results and predictions from competitive models. The proposed control methodology extends the results of the sliding mode theory to human motor control. The resulting adaptive control model of the motor system is robust to external dynamics, even those of negative gain, uses only position and velocity feedback, and achieves bounded steady-state error without explicit knowledge of the system's nonlinearities. In addition, the experimental and modeling results demonstrate that visuomotor learning is important not only for error correction through internal model adaptation on ground or in microgravity, but also for the minimization of the total mean-square error in the presence of random variability. Thus human intelligent decision displays certain attributes that seem to conform to Bayesian statistical games.
by Michail Tryfonidis.
Ph.D.
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Lim, keng gein. "P-delta Effects on a Steel Moment Frame Subjected to Sidesway Forces Caused by Unsymmetrical Live Load Patterns." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1622.
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Symmetrical steel moment frames that are subjected to sidesway forces due to unsymmetrical live loads will undergo sidesway. The P-delta effects on a moment frame under the influence of sidesway forces is studied. The effective length method is used for the second-order analysis specified in the American Institute Steel Construction - Load and Resistance Factor Design (AISC-LRFD). This study investigates the P-delta effects on a multi-story, multi-bay steel moment frame subjected to sidesway forces caused by various unsymmetrical live load patterns. The study focuses on the interaction of axial and bending moment in the columns. The actual response of a moment frame is estimated by amplifying the results of a first-order elastic analysis using moment magnification factors. The moment magnification factors for each story of the steel moment frame are summarized.
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DaBreo, Jamin. "Impact of gravity loads on the lateral performance of cold- formed steel frame/ steel sheathed shear walls." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114511.
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Canadian seismic design provisions for cold-formed steel framed/steel sheathed shear walls have been developed from previous research at McGill University with the intent of being incorporated into the Canadian section of the North American Lateral Design Standard for Cold-Formed Steel Framing (AISI S213), and ultimately to provide guidelines for design of these systems in the National Building Code of Canada and CSA-S136 Specification.In this previous research, a limited number of shear walls displayed unfavourable damage due to twisting deformations of the chord-studs and by local buckling. Also, the shear walls tested in previous research were only laterally loaded. The objective of the current research program was to address this unfavourable failure mode by evaluating the performance of cold-formed steel framed/steel sheathed shear walls, constructed with blocked stud members, which were tested under combined gravity and lateral loading. In total, fourteen single-storey shear walls (8 configurations) were subjected to monotonic and CUREE reversed cyclic lateral loading protocols. The Equivalent Energy Elastic-Plastic (EEEP) approach was used to analyse the test data and determine nominal shear resistance values. Relevant design parameters were determined: a resistance factor, phi, of 0.7, an overstrength value of 1.4, and ductility and overstrength seismic force modification factors (Rd = 2.0 and Ro = 1.3). Dynamic analysis of a two storey representative building model was carried out to validate the 'test-based' R-values following a methodology adopted from FEMA P695 to evaluate the seismic performance of a building system.The research program indicated that the blocking reinforcement detail had adequately resolved chord-stud twisting deformations and that the chord-studs, once designed to carry the combined gravity and lateral forces following a capacity based approach, would not fail thereby preventing any detrimental collapse of the framing system.Les dispositions de conception sismique pour les murs de refend (dotés de cadres ou de revêtements en acier laminé à froid) mises au point précédemment à l'Université McGill avaient pour but d'être ajoutées aux dispositions canadiennes présentées dans le North American Lateral Design Standard for Cold-Formed Steel Framing (AISI S213) et de proposer des lignes directrices qui pourraient être intégrées au Code national du bâtiment du Canada et à la norme CSA-S136. Au cours de ces recherches, un nombre limité de murs de refend ont été endommagés par le voilement local et les déformations des membrures-montants liées à la torsion. Les murs de refend avaient été uniquement testés sous l'effet d'une charge latérale. Ce programme de recherche tente de comprendre ce processus de défaut défavorable en évaluant la performance des murs de refend (dotés de cadres ou de revêtements en acier laminé à froid) construits à l'aide montants munis de cales et testés sous l'effet combiné de la gravité et de la charge latérale. Un total de quatorze murs de refend à un étage (8 configurations) ont été soumis aux protocoles de chargement monotone et de chargement cyclique-réversible de CUREE. La méthode équivalente de l'énergie élasto-plastique (EEEP) a été appliquée pour analyser les données des essais et déterminer les valeurs nominales de résistance au cisaillement. Les paramètres pertinents de conception ont été déterminés: un facteur de résistance (phi= 0.7), une valeur de sur-résistance de 1.4 et des facteurs de modification de force sismique reliés à la ductilité et à la sur-résistance (Rd = 2.0 et Ro = 1.3). Une analyse dynamique a été menée sur un modèle représentatif d'un bâtiment à deux étages pour valider les valeurs de R obtenues lors des essais. Une méthode adoptée par le FEMA P695 a servi à évaluer la résistance sismique d'un système de construction.Ce programme de recherche a montré que le dispositif de blocage de l'armature empêche adéquatement les déformations des membrures-montants liées à la torsion. Grâce à une approche de conception par capacité, des membrures-montants peuvent résister à l'action combinée de la gravité et des forces latérales, et ainsi prévenir l'effondrement de l'ossature du bâtiment.
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Dicleli, Murat. "Effects of extreme gravity and seismic loads on short to medium span slab-on-girder steel highway bridges." Thesis, University of Ottawa (Canada), 1993. http://hdl.handle.net/10393/6730.
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This study addresses two separate but related problems. They are detrimental effects of extreme gravity and seismic loadings, which were not considered in the original design, on slab-on-girder steel bridges. In the first part of this thesis the effect of extreme gravity loads on slab-on-girder steel bridges is studied. Currently, in many jurisdictions of North America, special permits are issued to extra-heavy vehicles considering only the ultimate capacity of the bridges. Based on this, a large number of special permits have been issued to extra-heavy vehicles, and therefore concerns have been raised since the cumulative effect of such overloads have never been assessed. In this perspective, the ultimate and cumulative effect of such overloads on bridge components is studied. Typical heavy permit-truck configurations are selected to investigate their effect on steel bridges. As a first step, influence line analyses are conducted to find the ranges of spans of simply supported and continuous bridges for which heavy permit-trucks have the most detrimental effects. In the light of these observations, a number of actual bridges within the estimated span length limits are analyzed to find the bridge members largely affected by such overloads. Next, a literature review is conducted to appraise the state-of-knowledge on the impact of infrequent stress-range excursions produced by heavy loads on fatigue life of bridge members. The effect of variable amplitude loading due to both Ontario truck traffic and heavy permit trucks on fatigue life of bridge members is investigated. Analytical expressions to calculate the fatigue life and the reduction in fatigue life of bridges due to heavy permit-trucks, without the need for a detailed analysis of each bridge, are derived and presented, along with a fatigue-based methodology to assess the reduction in service life of bridges attributable to heavy-permit trucks. Finally, using the derived equations, a sample permit-policy is presented assuming that a two percent reduction in fatigue life due to heavy permit-trucks is acceptable. In the second part, the response of bridge superstructure components to seismic excitations is investigated. Single span simply supported, continuous and multi-span simply supported bridges are studied by varying their geometric and structural properties. Linear and nonlinear dynamic analyses of these bridges are conducted for earthquakes of different characteristic and intensity considering only the superstructure. The forces and displacements of superstructure components which significantly affect the response, are determined as a function of the selected properties and earthquake types. Then, using these results, a methodology is developed for ranking and rapid seismic evaluation of existing steel bridges. Bearing forces due to seismic excitation in both transverse and longitudinal direction are found to be proportional to the mass of the bridge, span length, and bearings' stiffness. The effect of span length, number of spans, column size and steel strength on the seismic response of continuous and multi-span simply supported bridges are studied. Next, sliding of bridges after the bearings are severed is investigated. High intensity earthquakes are required to slide multi-span simply supported bridges when the bearings at the abutments are severed but single span simply supported and continuous bridges may have considerable sliding displacements depending on the $A\sb{p}/V\sb{p}$ ratio of earthquakes. The effect of cross-bracing as a retrofitting element for continuous and multi-span simply supported bridges is investigated. (Abstract shortened by UMI.)
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Gowda, Sunil. "Combined Effect of Gravity and Lateral Loads on the Formation of Plastic Hinges in Steel Moment Frames With Reduced Beam Sections." OpenSIUC, 2012. https://opensiuc.lib.siu.edu/theses/798.
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Inelastic behavior in steel special moment frames occurs through the development of plastic hinges at locations near the ends of the beam. The main objective of using a reduced beam connection is to force the formation of plastic hinges to be formed at the reduced beam section rather than at the ends of the beam which otherwise would lead to brittle failure of the beam-column connections. The beam has two reduced beam sections, each located at a certain distance from the face of the column, so that the plastic hinges are formed symmetrically at each of this section. When acted upon by lateral loads, the maximum moments occur at the ends of the beam. Therefore, the plastic hinges form at the reduced beam section. However, when a frame is subjected to a combination of gravity and lateral loads, the plastic hinge formation at one of the reduced beam section is not so clear and further analysis has to be done to study the effect. FEMA 350 indicates that the desired plastic hinge location is only valid for beams with gravity loads representing a small portion of the total flexural demand. If gravity demands significantly exceed 30% of the girder plastic capacity then further plastic analysis of the frame should be performed to determine the appropriate hinge locations. The scope of my thesis is mainly to study the combined effect of gravity and lateral loads on the formation of plastic hinges in steel moment frames with reduced beam section connections.
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IWASE, Satoshi, Qi FU, Kenichi NARITA, Eiichi MORIMOTO, Hiroki TAKADA, and Tadaaki MANO. "Effects of Graded Load of Artificial Gravity on Cardiovascular Functions in Humans." Research Institute of Environmental Medicine, Nagoya University, 2002. http://hdl.handle.net/2237/2775.
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Bazargani, Poureya. "Seismic demands on gravity-load columns of reinforced concrete shear wall buildings." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/46651.
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In shear wall buildings, walls serve as the seismic force resisting system while the gravity-load system consists of columns that are primarily designed to carry the weight of the building through frame action and are not detailed for seismic ductility. Design codes require the gravity-load system to be checked for deformation compatibility as the building deforms laterally. The process of checking the columns for adequate deformability still requires more work.
In addition to flexural deformations, components such as shear strain and rotation of the foundation contribute significantly to lateral deformations in the wall plastic hinge zone. Shear strains in flexural shear walls are analytically shown to be a result of large vertical tensile strains in areas with inclined cracks. Based on this theory, a simple design-oriented method for estimating shear strain profile of flexural shear walls is formulated, the accuracy of which is verified against experimental results from works of other researchers.
Rotation of shear wall foundations is studied through performing about 2000 Nonlinear Time-History Analysis (NTHA) considering the nonlinear interaction between the foundation and the underlying soil. Behaviour of shear walls accounting for foundation rotation is explained with emphasis on relative wall to foundation strengths. A simple method for obtaining the monotonic foundation moment-rotation response is formulated which is then used in a simple step-by-step method for estimating foundation rotation in a given shear wall building.
Curvature demand on columns pushed to a given wall deformation profile is studied using a structural analysis algorithm specifically designed for the task. In the absence of wall shear strain or significant foundation rotation, column curvature demand is found to remain close to the wall maximum curvature. Wall shear strain and foundation rotation are found to cause severe increase to column curvature demand. In a parametric study on column curvature demand, parameters including wall length, column length, height of column plastic hinge zone, first storey height, fixity of the column at grade level, and the effect of members framing into the column are studied. Several simple expressions for estimating column curvature demand are derived that can be implemented in design.
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Boberg, Björn, and David Holm. "FEM modeling of concrete gravity dams." Thesis, KTH, Vattendragsteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-99351.
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Hernández, Elder Alexandre de Sousa. "Final degree project: a dynamic study of fractured shafts submitted to only gravity load." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/9671.
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Mestrado em Engenharia MecânicaThis work is a reflection of the investigation on the field of rotor dynamics. The study of the dynamic behaviour of a cracked shaft is important not only to predict when the failure might occur but also to know at what extent it can still work in safe conditions. The nonlinearity of this behaviour can be studied through a FEM model and can provide a breakthrough to get raw data analysis of the breathing mechanism that occurs in dynamic cracked shafts submitted only to gravity load. The study of the breathing mechanism has been one of the directions that the field of rotor dynamics uses to obtain more data for an overall analysis of a cracked shaft behaviour.
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Charlet, Arnaud Yves. "Hybrid simulation and its application to the gravity load collapse of reinforced concrete frames." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31585.
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The structural testing method called hybrid simulation is implemented at the University of British Columbia. A tutorial is presented to assist the user on how to perform hybrid simulation of structural systems using the finite element software OpenSees, the software framework for hybrid simulation OpenFresco and an event-driven predictor-corrector scheme ensuring continuous testing. Geographically distributed hybrid simulation is introduced and distributed tests performed between the University of British Columbia and the University of California, Berkeley, are described. A hybrid simulation test setup is developed to investigate and validate the application of hybrid simulation to the gravity load collapse of reinforced concrete frames. A shear-critical reinforced concrete column loaded through three dynamic actuators constitutes the physical substructure while a nonlinear ductile reinforced concrete frame makes up the numerical substructure within the OpenSees environment. A nonlinear transformation method is implemented to allow for an accurate application of the three-degree-of-freedom loading on the specimen through the three-actuator test setup, and a specific predictor-corrector algorithm with variable actuator speed is designed to ensure smooth continuous testing despite the use of an implicit iterative integration scheme. Furthermore, a methodology using an iterative predictor-corrector algorithm with mode-switch is developed to enable the use of force control for the actuators in combination with a displacement-based finite element analysis engine. Results from the hybrid tests are compared with a shaking table test of the same structure, and are shown to exhibit the same general behaviour: shear and axial load failure of the shear-critical column followed by gravity load redistribution. However, the inability of the analytical model to capture the residual drifts observed in the shake table tests resulted in an underprediction of the drift demand on the system.Applied Science, Faculty of
Civil Engineering, Department of
Graduate
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Elwood, Kenneth Moehle Jack P. "Shake table tests and analytical studies on the gravity load collapse of reinforced concrete frames /." Berkeley : Pacific Earthquake Engineering Research Center, 2003. http://peer.berkeley.edu/publications.
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Hopper, Michael W. Lepage Andres. "The John Jay College Expansion Project a study of an Alternative Gravity Load Transfer System /." [University Park, Pa.] : Pennsylvania State University, 2009. http://honors.libraries.psu.edu/theses/approved/WorldWideIndex/EHT-8/index.html.
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Akhtar, Mohammad Farhan. "Numerical Investigation of High Strength Structural Steel Gravity Columns at Elevated Temperature." University of Cincinnati / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1613748386003217.
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Centeno, Jose. "In-plane shake table testing of gravity load designed reinforced concrete frames with unreinforced masonry infill walls." Thesis, University of British Columbia, 2009. http://hdl.handle.net/2429/7211.
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Common construction practice before modern seismic design codes appeared allowed designing columns lap splices located above the slab in each floor or above the foundation. The lack of lap splices and the shear reinforcement was in the form of stirrups with 90-degree bends and spaced at half the depth of the frame member. As a result, the section at the base of these columns is unconfined and susceptible to shear failure or to a premature failure of the lap splices before yielding of the longitudinal bars.
The masonry infill walls used as partitions were often ignored by design engineers since such walls were considered as nonstructural architectural elements. However, lessons learned from past earthquakes and from several tests performed have shown that those walls tend to interact with the bounding frame when the structural system is subjected to moderate or severe earthquake ground motions.
The first part of an experimental testing program carried out at the University of British Columbia (UBC) in Vancouver, Canada tested the performance of 1/2 scale Gravity Load Designed Reinforced Concrete (GLDRC) frames with unreinforced masonry walls. This testing program consisted of one monotonic loading test on an infilled frame and two series of shake table tests, one on an infilled frame and one on a bare frame with the UBC Earthquake Engineering Research Facility (EERF) unidirectional shake table.
It was concluded from these tests that the interaction with the unreinforced masonry wall stiffens the frame, reduces the deformations, and allows dissipating energy through nonlinear response for several cycles of deformation. It was determined that the governing failure mode for the masonry wall was shear sliding for monotonic and dynamic loading. There was consistent evidence of local lateral deformations at the base of the gravity load designed columns due to construction cold joints and inadequate lap splices that may result in shear failure of the base of the column due to the interaction with the masonry infill during a severe earthquake.
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Mummidivarapu, Satya Sri. "A Method for Determining Body Weight Replacement Load during Squat Exercise in Weightlessness." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447690685.
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Wright, Timothy R. "Full-scale seismic testing of a reinforced concrete moment frame using mobile shakers." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/54414.
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A prototype reinforced concrete moment frame representative of low-rise office buildings in the Central and Eastern United States from the 1950s-1970s was designed and selected for evaluation under seismic loads. A plane frame specimen from the prototype was incorporated into the design of a test-bed of four full-scale, side-by-side nominally identical structures that could be evaluated independently. The testing of the first frame serves as the topic of this dissertation. The specimen was two bays x two stories x 9-ft. wide. A new method for testing full-scale structures under seismic loads was proposed that used a hydraulic linear inertial shaker (LIS) to impart seismic loads. The response of the structure was monitored using 155 strain gages, 38 linear variable differential transformers, six string potentiometers, and 42 accelerometers. The response of the frame to a series of 25 load histories using the nees@UCLA LIS was marked by gradual structural softening and minimal yielding of the steel reinforcing throughout the structure. At a first interstory drift of 1.5% some yielding of the reinforcing bars was measured. Between 1.5% and 2% first interstory drift, a global sway mechanism formed when the failure of a splice at the base of the first story west column led to a cascading set of failures within other first-story column splices. The experimental behavior suggests previous scaled testing of similar structures may have inadequately represented the vulnerability column splices. The design of the test-bed, response of the structure to seismic loads, qualitative evaluation of the test method, and implications on future research are discussed.
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Danza, Matthew Anthony. "Lateral Restraint Brace Forces in Quarter Point and Third Point Plus Support Braced Z-Purlin Supported Roof Systems Subject to Gravity Load." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36281.
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The objective of this study was to develop design equations that predict lateral restraint forces in two commonly used Z-purlin supported roof systems. These are quarter point bracing and third point plus support bracing. To that end, a stiffness model used in the past has been reintroduced. This model has been modified slightly to better represent roof system behavior. The updated stiffness model was then used to estimate lateral restraint forces for a number of roof systems with a varying cross sectional dimensions of the purlin, number of purlin lines, number of spans, and span length. A regression analysis was then performed on the data to obtain empirical design equations similar to those found in the 1996 Edition of the American Iron and Steel Institute's Specification for the Design of Cold-Formed Steel Members, Section D.3.2.1.
Vita removed April 4, 2011. GMc
Master of Science
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Novotný, Michal. "Vliv uložení nákladu na bezpečnost jízdy nákladního vozidla." Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2010. http://www.nusl.cz/ntk/nusl-232467.
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The objection of this dissertation is to examine effects of stowed cargo on safety driving of a vehicle. Based on general experience of weighing trucks and monitoring of cargo fixture, my attempt was to summarize related legislative conditions of the operation of trucks in terms of payload, weighing and stowing of cargo. In the first part I worked on consistent methodology of stowing and fastening of cargo on trucks. I've included various methods of loading cargo and different ways of fastening and their calculations. The main body of the second part is a practical methodology of inspectional weighing of trucks on the road. In this section I took into account the current method and procedure of inspectional weighing and measuring of trucks. During my trial weighing of different types of trucks I proved that the key factor for safe seating and lashing of load on a vehicle is determining center of gravity of the vehicle. I solve this problem in detail in the last part of my work.
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Forman, Tomáš. "Modifikace přistávacího zařízení letounu Irbis." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-442836.
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This master thesis deals with the landing gear rebuild from tail gear to nose gear of the M-4 Irbis aircraft. The first chapter presents the aircraft in its current state and includes some technical data, too. The theoretical information about types of landing gears, its characteristics, pros and cons and the typical representatives for each type of landing gear are mentioned in the second chapter. The third chapter is about landing gear loads that occur during landing and about the load calculation according to UL 2 regulation. The following chapter shows the construction of the new landing gear, including some of the suggested, but not realised, designs. In the fifth chapter, there is a landing gear strength calculation of some of the gear components. The calculation is analytical and then uses FEM. The very last chapter then shows the effect of new landing gear on the centre of gravity in its extreme positions. The chapter also compares aircraft masses with both landing gears.
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Jin-KaiWang and 王勁凱. "Settlements of Gravity Foundations Under Vertical Loads." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/79355483832961981822.
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碩士國立成功大學
土木工程學系碩博士班
100
Wind power has been most mature technology for development of renewable energy. Gravity foundations are used as foundation structures for wind turbines. It is well known that cyclic loading of foundations arises mainly from wind loads may leads to an accumulation of permanent settlement and may decrease the soil bearing capacity with the number of loading cycles. This study is used modified Degradation stiffness model (Kuo, 2008) and introduced into modified O’Loughlin ＆ Lehan (2010) settlement prediction method to analysis the deformation performance of gravity foundations embedded in cohesionless soils under cyclic loading. Settlements of foundations that both under static loading and cyclic loading, can be predicted accurately through the method that developed in this study by using plate loading test as a reference as gravity foundations are designed.
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Argudo, Jaime Fernando. "Non-destructive evaluation of gravity load carrying capacity and lateral load damage of reinforced concrete slab-column connections." Thesis, 2006. http://hdl.handle.net/2152/2458.
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Muhaj, Helisa. "Seismic strengthening of reinforced concrete beams by post-tensioning with anchorages by bonding." Doctoral thesis, 2020. http://hdl.handle.net/10362/103102.
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RC moment resisting frame buildings are one of the most used structural systems in seismic
prone regions. These structures dissipate energy by concentrating the inelastic behaviour (i.e. the damage)
in the plastic hinge regions of the structural elements, that form preferably on the beams ends.
Since Capacity Design has been part of the Design Codes for some years now, some moment resisting
frame buildings have suffered seismic events. Although in most of the cases the ductile performance
of structures has successfully preserved the human lives and no collapse has occurred, deficiencies
regarding the residual capacity and high level of post-earthquake damages have surfaced. The importance
of other solutions that offer higher cost-efficiency and are more resilient has emerged.
Some studies have shown that damage limitation leads to high seismic performance of structural
systems even. This technology was developed at first for application in precast industry, PRESSS
program. Considering the vast amount of existing structures built following the Capacity Design and
the advantages of Damage Avoidance Design, strengthening by post-tensioning with adhesive anchorages
is proposed in this dissertation as a promising intervention for improving the seismic behaviour
of ductile beams. This solution takes advantage of self-centering capacity of unbonded PT strands,
whereas development of bonded anchorages turns this solution suitable for application in residential
/ business frame buildings. The results obtained from four RC beams tested experimentally will be
presented herein, including one reference and three strengthened specimens. The strengthened beams
had reduced residual deformation and enhanced load capacity. The behaviour of the beams tested
experimentally was also studied through numerical analysis. The attained results show that strengthening
by post-tensioning with bonded anchorages represents a suitable intervention for reducing the
impact of seismic events. Reduced damage of structural elements in RC frame after a seismic event
leads to reduced (or absence) cost of repair and building downtime.