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Dissertations / Theses on the topic 'Flood Control Structures'
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1
Duke, Jacquelyn R. White Joseph Daniel. "The response of riparian vegetation to PL-566 flood control structures." Waco, Tex. : Baylor University, 2006. http://hdl.handle.net/2104/4214.
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Malyevac, David Stephen. "Modeling the flash gate board for water storage and flood control." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/80069.
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The height of an overflow dam must be designed low enough to prevent the reservoir water level from exceeding a flood plain during flooding conditions. Because of this constraint, much of the available water storage area is wasted and the available pressure head for power generation will be less than maximum during normal conditions. Crest control gates alleviate this problem by providing a variable spillway height. The Flash Gate Board is a passive automatic crest control gate. Its purpose is to regulate flood water while providing increased water pressure for power generation or for additional water storage for a municipality. The governing equations for the Flash Gate Board system are derived and used to formulate models of the system. Computer simulations are used to examine the system response in a variety of operating conditions. The results of these simulations are presented and discussed. The results include an investigation which developed an optimum gate height to maximize the potential of the Flash Gate Board. An experimental model was developed to verify analytical results and to provide additional insight. Conclusions from the study, recommendations for future work, and modifications for a trouble-free design are discussed.<br>Master of Science
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Bozkurt, Okan Cagri. "Operation Of The Water Control Structures." Master's thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615419/index.pdf.
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Floods are one of the most important natural disasters regarding damages caused by them. Major reasons of huge damages of floods are unplanned urbanization, narrowing of river beds and incorrect operation of water control structures. Geographic Information Systems (GIS) can provide important tools to be used in flood modeling studies. In this study, Lake Mogan, Lake Eymir and Incesu Detention Pond subbasins are studied for flooding events within GIS framework. These subbasins are important catchment areas of city of Ankara with total drainage area of 1070 km2. Soil Conservation Service (SCS) method is used to obtain flood hydrographs for 12 hour duration and 50, 100 and 500 year return periods. Flood routing procedure is applied to obtain discharges at the outlet of the Mogan and Eymir Lakes and Incesu Detention Pond. Operation performance of water control structures are tried to be estimated by using hydrographs which are obtained for different scenarios. Results show that elements of Lake Mogan Water Control Structure do not have capability to discharge 500 year storm safely to the downstream of the lake. However, 100 year storm can be routed without creating problem if necessary small precautions are taken. On the other hand, water control elements of Lake Eymir and Incesu Detention Pond can transmit obtained flood volumes to the downstream parts by assuming that closed conduit at the exit of Incesu Detention Pond can safely convey resultant flood discharges.
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Ischen, Marc. "Using Two-Dimensional Numerical Models to Analyze Hydraulic Effects of Constricted Flows through the Rigolets Pass between Lake Pontchartrain and Lake Borgne." ScholarWorks@UNO, 2009. http://scholarworks.uno.edu/td/922.
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The objective of this study was to determine if numerical models commonly used for large scale applications could also be used to model flow through flood control structures in the Rigolets Pass between Lake Borgne and Lake Pontchartrain. For this purpose a small scale physical model was built. It showed that bi-stable flow can develop downstream of a constriction. Small changes in the distribution of the approaching flow significantly impacted flows downstream of the constriction. This behavior could not be properly reproduced by a small scale 2-dimensional RMA2 model of identical dimensions. A large scale RMA2 model of the Rigolets testing possible locations and geometries of flood control structures showed that this pass is very sensitive to variations in the cross sectional flow area. Even minor reductions can significantly increase headlosses and velocities. To reduce negative impacts a flood control structure should be built in a wide and shallow area of the pass.
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Schroeder, Robin L. "Exchange flows in an urban water body: Bayou St. John responses to the removal of flood control structures, future water elevation control, and water quality." ScholarWorks@UNO, 2011. http://scholarworks.uno.edu/td/1394.
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Bayou St. John, an urban water body extending south from Lake Pontchartrain, has two anthropogenic structures that regulate flow from the Lake . The City of New Orleans has plans to remove the inner control structure to improve water quality. Field and numerical methods used in this study show removing this structure increased water elevations throughout the Bayou but resulted in lower water elevation signal amplitudes that caused a lower tidal flow exchange from north to south. Bulk Richardson numbers showed mixing was inversely related to flow and the Bayou generally remains stratified. Resuspension of contaminated sediment could negatively impact the local ecology but predicted shear stress values did not reach a critical value (0.1 N/m2) for resuspension. Removal of the waterfall structure will benefit Bayou St. John by decreasing energy losses from the Lake, however a more pronounced tidal signal from Lake Pontchartrain is required to flush the Bayou.
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Hanagan, Linda M. "Active control of floor vibrations." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-164824/.
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Warmington, Valerie (Valerie A. ). Carleton University Dissertation Geography. "Structural flood control and sustainable development; an analysis of the flood action plan for Bangladesh." Ottawa, 1994.
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Vu, Duc-Chuan. "Contrôle sismique des structures." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLY015/document.
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Cette thèse est motivée par diverses questions qui se posent quant à l’utilisation de l’isolation sismique dans l’industrie nucléaire. À la différence de la grande majorité des travaux antérieurs sur l’isolation sismique en générale et l’isolation mixte en particulier, qui portent principalement leur intérêt sur la réponse de la structure isolée (déplacements relatifs, accélérations maximales des étages, etc.), une grande partie de ce travail est consacrée au comportement des équipements, par le biais de l’étude des spectres de plancher. L’objectif principal est de diminuer la déformation des isolateurs sans amplification de la réponse des modes supérieurs, qui peut apparaître sous certaines conditions et qui peut être une source de sollicitation des équipements. Pour ce faire, des alternatives aux appuis parasismiques couramment utilisés sont explorées. Il s’agit des combinaisons d’un appui à faible amortissement avec un élément de Maxwell (isolateur de relaxation) ou avec un amortisseur hydraulique semi-actif (système d’isolation mixte). L’élément de Maxwell se comportant comme un amortisseur à basse fréquence et un ressort de faible rigidité à haute fréquence permet de satisfaire l’objectif souhaité. En ce qui concerne les systèmes d’isolation mixtes, trois techniques de contrôle semi-actif sont proposées. Afin d’améliorer la performance du contrôle, une attention particulière a été donné à la prise en compte de l’excitation sismique et des caractéristiques de l’amortisseur lors de la conception du contrôleur est focalisée. Les analyses numériques confirment l'efficacité de ces systèmes. En vue de l’utilisation de ces méthodes pour de structures réelles, certains aspects pratiques comme, par exemple, l’observation du système, les effets de la réduction du modèle utilisé par le contrôleur ou du temps de retard sur la performance du contrôle, ainsi que le contrôle d’un ensemble de plusieurs dispositifs semi-actifs redondant, sont, également, abordés<br>This thesis is motivated by various questions that arise regarding the use of base isolation in the nuclear industry. Unlike the majority of previous work on base isolation in general and mixed isolation in particular, which focus mainly on the response of the isolated structure (interstorey drifts, maximum accelerations of floors, etc.), this work focuses on the behavior of equipment, through the study of floor response spectra. The main objective is to reduce the deformation of the isolators without amplification of the response of the higher modes, which may appear under certain conditions and which can be a source of equipment solicitation. To this end, alternatives to the commonly used base isolators are explored. These are combinations of a low damping rubber bearing with a Maxwell element (relaxation isolator) or a semi-active hydraulic damper (mixed base isolation system).Maxwell element behaves like a damper in low frequency and as a low stiffness spring in high frequency. Hence it meets the above objectives. . Regarding isolation systems, three semi-active control techniques are proposed. In order to improve the performance of the control, the seismic excitation and the characteristics of the damper are taken into account in the design of the controller. Numerical analyzes confirm the effectiveness of these systems. Having in mind implementation of these methods to real structures, some practical aspects such as, observation of the system, effects of model reduction, considered by the controller, or time delay on the control performance, as well as the control of a set of redundant semi-active devices, are also studied
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Huong, Tung Chun. "Two-Dimensional Analysis of Water-Filled Geomembrane Tubes Used as Temporary Flood-Fighting Devices." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/31308.
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A water-filled geomembrane tube is considered for the purpose of temporary flood protection. With proper design, this tube can be a cheap and efficient breakwater, temporary levee, or cofferdam. This thesis considers a single tube resting on clay and sand foundations.
A finite difference program, FLAC, is used in the numerical analyses. The tube is assumed to be infinitely long, and it is modeled two-dimensionally. Beam elements are used to model the tube. The tube is inflated with water. The hydrostatic pressure in the tube is converted to point loads and applied at the beam nodes in the direction perpendicular to the chord connecting two adjacent nodes.
Two of FLACâ s built-in soil models are used: elastic and Mohr-Coulomb. The Mohr-Coulomb model is used in all the cases except the preliminary analyses, in which the elastic soil model is used. The Mohr-Coulomb soil model is able to model the soilâ s nonlinear stress-strain and path-dependent deformation behavior.
A tube without external water is placed on clay with various shear strengths to study how the clay consistency affects the height and the stresses in the tube. A tube with external water on one side is placed on medium dense sand. A wooden block is placed on the side opposite the floodwater. Three types of block geometry and two sizes are studied. The floodwater level is increased until the system fails. Three failure modes, rolling, sliding, and piping, are studied. The effect of pore pressure on these failure modes is examined. The influence of a filter placed under part of the tube and block is also investigated.
The tubeâ s tensile forces, shear forces, moments, and settlements are included. Soil stresses and pore pressures at the soil-tube interfaces are computed. The cross-section of the tube at various external water levels, and the pore pressures in the soil, are calculated. These results are compared with experimental results that were obtained by graduate students in geotechnical engineering at Virginia Tech.<br>Master of Science
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Vu, Duc-Chuan. "Contrôle sismique des structures." Electronic Thesis or Diss., Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLY015.
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Cette thèse est motivée par diverses questions qui se posent quant à l’utilisation de l’isolation sismique dans l’industrie nucléaire. À la différence de la grande majorité des travaux antérieurs sur l’isolation sismique en générale et l’isolation mixte en particulier, qui portent principalement leur intérêt sur la réponse de la structure isolée (déplacements relatifs, accélérations maximales des étages, etc.), une grande partie de ce travail est consacrée au comportement des équipements, par le biais de l’étude des spectres de plancher. L’objectif principal est de diminuer la déformation des isolateurs sans amplification de la réponse des modes supérieurs, qui peut apparaître sous certaines conditions et qui peut être une source de sollicitation des équipements. Pour ce faire, des alternatives aux appuis parasismiques couramment utilisés sont explorées. Il s’agit des combinaisons d’un appui à faible amortissement avec un élément de Maxwell (isolateur de relaxation) ou avec un amortisseur hydraulique semi-actif (système d’isolation mixte). L’élément de Maxwell se comportant comme un amortisseur à basse fréquence et un ressort de faible rigidité à haute fréquence permet de satisfaire l’objectif souhaité. En ce qui concerne les systèmes d’isolation mixtes, trois techniques de contrôle semi-actif sont proposées. Afin d’améliorer la performance du contrôle, une attention particulière a été donné à la prise en compte de l’excitation sismique et des caractéristiques de l’amortisseur lors de la conception du contrôleur est focalisée. Les analyses numériques confirment l'efficacité de ces systèmes. En vue de l’utilisation de ces méthodes pour de structures réelles, certains aspects pratiques comme, par exemple, l’observation du système, les effets de la réduction du modèle utilisé par le contrôleur ou du temps de retard sur la performance du contrôle, ainsi que le contrôle d’un ensemble de plusieurs dispositifs semi-actifs redondant, sont, également, abordés<br>This thesis is motivated by various questions that arise regarding the use of base isolation in the nuclear industry. Unlike the majority of previous work on base isolation in general and mixed isolation in particular, which focus mainly on the response of the isolated structure (interstorey drifts, maximum accelerations of floors, etc.), this work focuses on the behavior of equipment, through the study of floor response spectra. The main objective is to reduce the deformation of the isolators without amplification of the response of the higher modes, which may appear under certain conditions and which can be a source of equipment solicitation. To this end, alternatives to the commonly used base isolators are explored. These are combinations of a low damping rubber bearing with a Maxwell element (relaxation isolator) or a semi-active hydraulic damper (mixed base isolation system).Maxwell element behaves like a damper in low frequency and as a low stiffness spring in high frequency. Hence it meets the above objectives. . Regarding isolation systems, three semi-active control techniques are proposed. In order to improve the performance of the control, the seismic excitation and the characteristics of the damper are taken into account in the design of the controller. Numerical analyzes confirm the effectiveness of these systems. Having in mind implementation of these methods to real structures, some practical aspects such as, observation of the system, effects of model reduction, considered by the controller, or time delay on the control performance, as well as the control of a set of redundant semi-active devices, are also studied
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Al-Rumaih, Wail Saad. "A novel tuned visco-elastic damper for floor vibration abatement." Dayton, Ohio : University of Dayton, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1245387294.
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Cotton, Stephen Andrew. "Two-Dimensional Vibrations of Inflated Geosynthetic Tubes Resting on a Rigid or Deformable Foundation." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/9715.
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Geosynthetic tubes have the potential to replace the traditional flood protection device of sandbagging. These tubes are manufactured with many individual designs and configurations. A small number of studies have been conducted on the geosynthetic tubes as water barriers. Within these studies, none have discussed the dynamics of unanchored geosynthetic tubes.
A two-dimensional equilibrium and vibration analysis of a freestanding geosynthetic tube is executed. Air and water are the two internal materials investigated. Three foundation variations are considered: rigid, Winkler, and Pasternak. Mathematica 4.2 was employed to solve the nonlinear equilibrium and dynamic equations, incorporating boundary conditions by use of a shooting method.
General assumptions are made that involve the geotextile material and supporting surface. The geosynthetic material is assumed to act like an inextensible membrane and bending resistance is neglected. Friction between the tube and rigid supporting surface is neglected. Added features of viscous damping and added mass of the water were applied to the rigid foundation study of the vibrations about the freestanding equilibrium configuration.
Results from the equilibrium and dynamic analysis include circumferential tension, contact length, equilibrium and vibration shapes, tube settlement, and natural frequencies. Natural frequencies for the first four mode shapes were computed. Future models may incorporate the frequencies or combinations of the frequencies found here and develop dynamic loading simulations.<br>Master of Science
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Coopey, Richard. "Structures of control : the changing role of shop floor supervision in the U.S. automobile industry, 1900-1950." Thesis, University of Warwick, 1988. http://wrap.warwick.ac.uk/3966/.
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The thesis is based on a longitudinal study of the automobile industry in the U.S.A. from its inception around the turn of the century, to the 1950s. Charting the changes in methods of production, organisational structure, demography and skill configurations among the workforce, and institutional and political formations at the workplace, the study focuses upon the meaning of these developments in terms of the control of work and the personnel directly involved in that control - the changing role of foremen in 20th century industry. Using a range of sources including contemporary governmental and industrial surveys, company and trade union records and oral histories, a picture is built up of the way in which methods of production, and the control of that production, are mediated through a series of social, demographic, spatial and ideological factors, in all of which the foreman is a central character. In examining the role of shop floor supervision in shaping workers experience and actual structures of control at the workplace, and showing how the experience of foremen, individually and as a group, in turn are affected by changing patterns of work, the thesis constructs a historical modification to accounts of the labour process which stress a progressive, teleological exodus of control from the shop floor. The study points out for example, that the role of shop-floor supervisor during the inter-war period, largely supposed to have been proscribed and marginalised by technological and bureaucratic developments, remained in fact the focal point of control over hiring, firing, wage levels, production levels and methods of work, in short almost all aspects of the industrial workers' experience of factory life. Having established the boundaries of power and control surrounding the foreman in pre-war mass production, and discussed the meaning of these boundaries in terms of class, ideology and divisions among the workforce, the thesis then examines the origins and effects of unionisation on the role of supervision. Following an account of the restructuring of power and control which comes with the establishment of production workers unions in the industry, the advent of the unionisation of foremen themselves is examined. The Foremen's Association of America (FAA), which saw its genesis and principal area of recruitment in the automobile industry, represented the most serious attempt to organise supervisory workers in the USA this century, and marks a pivotal point in the spread of unionisation, managerial response and state intervention in industrial relations. Building on earlier sections outlining the position of foremen in terms of power and ideology, the thesis proposes a complex, multi-level dynamic behind the formation, growth and decline of the FAA as a corrective to previous accounts which stress the primacy of legislative and institutional explanatory frameworks. Finally the thesis charts the post-war response of management in the industry to the threat of foremen's unionisation, locating ensuing attempts to restructure the role, status and prestige of foremen in terms of the historical impact and progress of competing managerial theory, in particular that of the human relations school.
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Koo, Jeong-Hoi. "Using Magneto-Rheological Dampers in Semiactive Tuned Vibration Absorbers to Control Structural Vibrations." Diss., Virginia Tech, 2003. http://hdl.handle.net/10919/29023.
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Since their invention in the early 1900s, Tuned Vibration Absorbers (TVAs) have shown to be effective in suppressing vibrations of machines and structures. A vibration absorber is a vibratory subsystem attached to a primary system. It normally consists of a mass, a spring, and a damper. Mounted to the primary system, a TVA counteracts the motions of the primary system, "absorbing" the primary structure's vibrations. A conventional passive TVA, however, is only effective when it is tuned properly, hence, the name "tuned" vibration absorber. In many practical applications, inevitable off-tuning (or mistuning) of a TVA occurs because of the system's operating conditions or parameter changes over time. For example, the mass in a building floor could change by moving furnishings, people gathering, etc., which can "off-tune" TVAs. When TVAs are off-tuned, their effectiveness is sharply reduced. Moreover, the off-tuned TVAs can excessively amplify the vibration levels of the primary structures; therefore, not only rendering the TVA useless but also possibly causing damage to the structures. Off-tuning is one of the major problems of conventional passive TVAs.
This study proposes a novel semiactive TVA, which strives to combine the best features of passive and active TVA systems. The semiactive TVA in this study includes a Magneto-Rheological (MR) damper that is used as a controllable damping element, for providing the real-time adjustability that is needed for improving the TVA performance.
This study is conducted in two phases. The first phase provides a numerical investigation on a two-degree-of-freedom (2-DOF) numerical model in which the primary structure is coupled with a TVA. The numerical investigation considers four semiactive control methods for the MR TVAs, in addition to an equivalent passive TVA. These numerical models are optimally tuned using numerical optimization techniques to compare each TVA system. These tuned systems then serve as the basis for numerical parametric studies for further evaluation of their dynamic performance. The parametric study covers the effects of damping, as well as system parameter variations (off-tuning). The results indicates that semiactive TVAs are more effective in reducing the maximum vibrations of the primary structure and are more robust when subjected to off-tuning. Additionally, the numerical study identifies the "On-off Displacement-Based Groundhook control (on-off DBG)" as the most suitable control method for the semiactive TVA among control methods considered in this study.
For the second phase of this study, an experimental study is performed on a test setup, which represents a 2-DOF structure model coupled with an MR TVA. Using this setup, a series of tests are conducted in the same manner as the numerical study to evaluate the performance of the semiactive TVA. The primary purposes of the experiment are to further evaluate the most promising semiactive control methods and to serve as a "proof-of-concept" of the effectiveness of this MR TVA for floor vibration applications. The results indicate that the semiactive TVA with displacement-based groundhook control outperforms the equivalent passive TVA in reducing the maximum vibrations of the primary structure. This confirms the numerical result that identifies on-off DBG control method as the "best" control method for the MR TVA among four semiactive control schemes considered. The experimental robustness study is also conducted, focusing on the dynamic performance of both the passive and the semiactive TVAs when the mass of the primary system changes (mass off-tuning). The mass of the primary system varied from -23 % to +23 % of its nominal value by adding and removing external masses. The experimental results show that the semiactive TVA is more robust to changes in the primary mass than the passive TVA.
These results justify the benefits of the use of semiactive MR TVAs in structures, such as building floor systems. The off-tuning analysis further suggests that, in practice, semiactive TVAs should be tuned slightly less than their optimum in order to compensate for any added masses to the structure. Additionally, the lessons learned from the experimental study have paved the way for implementing the semiactive MR TVA on a test floor, which is currently in progress under a separate study.<br>Ph. D.
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Vaněk, Petr. "Posouzení vodního díla Těšetice za povodní." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2016. http://www.nusl.cz/ntk/nusl-240338.
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The Diploma Thesis focuses on the assessment of the current state of VD Tesetice to convert KPV parameters Q1000. Based on this evaluation, the thesis proposes corrective actions on waterwork constructions for the purpose of protection of their functioning during floods. Proposed corrective actions consist of designing new or additional safety features, mainly security spillway in abutment terrain.
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Liu, Di. "VIBRATION OF STEEL-FRAMED FLOORS SUPPORTING SENSITIVE EQUIPMENT IN HOSPITALS, RESEARCH FACILITIES, AND MANUFACTURING FACILITIES." UKnowledge, 2015. http://uknowledge.uky.edu/ce_etds/34.
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Floors have traditionally been designed only for strength and deflection serviceability. As technological advances have been made in medical, scientific and micro-electronics manufacturing, many types of equipment have become sensitive to vibration of the supporting floor. Thus, vibration serviceability has become a routinely evaluated limit state for floors supporting sensitive equipment. Equipment vibration tolerance limits are sometimes expressed as waveform peak acceleration, and are more often expressed as narrowband spectral acceleration, or one-third octave spectral velocity.
Current floor vibration prediction methods, such as those found in the American Institute of Steel Construction Design Guide 11, Floor Vibrations Due to Human Activity, the British Steel Construction Institute P354, Design of Floors for Vibration: a New Approach and the British Concrete Centre CCIP-016 A Design Guide for Footfall Induced Vibration of Structures, have limitations. It has been observed that non-structural components such as light-weight partitions could significantly change floor dynamic properties. Current prediction methods do not provide a fundamental frequency manual prediction method nor finite element modeling guidance for floors with non-structural components. Current prediction methods only predict waveform peak acceleration and do not provide predictions for frequency domain response including narrowband spectral acceleration or one-third octave spectral velocity. Also, current methods are not calibrated to provide a specific level of conservatism.
This research project provides (1) a fundamental frequency manual prediction method for floors with lightweight partitions; (2) an improved finite element modeling procedure for floors with light-weight partitions; (3) a procedure to predict the vibration response in narrow-band spectrum and one-third octave band spectrum which can be directly compared with vibration tolerance limits; and (4) a simplified experimental procedure to estimate the floor natural frequencies.
An experimental program including four steel-framed building floors and a concrete was completed. Modal tests were performed on two of the steel-framed buildings and the concrete building using an electrodynamic shaker. Experimental modal analysis techniques were used to estimate the modal properties: natural frequencies, mode shapes, and damping ratios. Responses to walking excitation were measured several times in each tested bay for individuals walking at different walking speeds. During each test, the walker crossed the middle of the bay using a metronome to help maintain the intended cadence.
The proposed method was used to predict the modal properties and responses to walking. The measurements are used to assess the precision of the proposed methods and to calibrate the prediction methods to provide a specific probability that the actual response will exceed the predicted response. Comparison of measurements and predictions shows the proposed methods are sufficiently accurate for design usage.
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Teodorescu, Catalin Stefan. "Commande de systèmes d'isolation antisismique mixte." Phd thesis, Université Paris Sud - Paris XI, 2013. http://tel.archives-ouvertes.fr/tel-00904280.
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Nous nous intéressons aux méthodes de contrôle de vibrations de modèles réduits de structures à n degrés de liberté, sismiquement isolées au niveau de la base par des systèmes d'isolation mixte.Le mouvement provoqué par une sollicitation sismique horizontale a lieu dans le plan vertical.Nous avons construit un problème de contrôle semi-actif de systèmes incertains soumis à des perturbations inconnues, mais bornées. Dans le langage de l'automatique, il s'agit d'un problème d'atténuation de perturbations.Le résultat principal de cette thèse porte sur la construction d'une version modifiée des résultats de Leitmann et de ses collaborateurs sur la stabilisation de systèmes non linéaires incertains. Le théorème proposé repose sur une loi de commande par retour d'état qui assure en boucle fermée les propriétés de "uniform boundedness" et "uniform ultimate boundedness".En particulier, il peut être appliqué à la résolution de problèmes de contrôle semi-actif, qui sont actuellement traités en génie parasismique.L'objectif du contrôle est d'améliorer le comportement (i.e. la réponse) de structures isolées pour faire face aux perturbations externes, c'est-à-dire les séismes. Plusieurs points différencient notre problème de la majorité que l'on trouve dans la littérature: (i) on ne s'intéresse pas seulement à la protection de la structure isolée, mais aussi aux équipements situés à l'intérieur de la structure, et (ii) au lieu d'utiliser des indicateurs de performance habituels exprimés en termes de déplacement relatif de la base versus des accélérations absolues des planchers, nous utilisons uniquement le spectre de plancher en pseudo-accélération, comme il a été proposé dans des travaux précédents par Politopoulos et Pham. Ce travail est une tentative d'utiliser explicitement les spectres de plancher comme critère de performance.Concernant la procédure d'application, plusieurs étapes intermédiaires ont été détaillées:(i) modélisation de signaux sismiques;(ii) réglage des paramètres de la loi de commande utilisant la théorie des vibrations;(iii) validation et test du comportement en boucle fermée à travers des simulations numériques: pour des raisons de simplicité, on se limite au cas n=2.Cette procédure peut être utilisée sur des structures en industrie nucléaire, mais aussi en génie civil.D'autres sujets traités incluent une tentative d'utiliser les outils temps-fréquence, et en particulier la distribution de Wigner-Ville, pour la synthèse de lois de commande, en espérant pouvoir mieux contrôler les composants transitoires des signaux de perturbation (les entrées) et des variables d'état (les sorties).
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Šemberková, Klára. "Stavebně technologický projekt bytového domu Fryčajova, Brno." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-372232.
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The subject of my master´s thesis is architectural and technological project of a residental building Fryčajova, Brno. My work contain engineering report of architectural and technological project, study of realization of the main stage, project of site equipment, design of building mechanization, time plans, technological note of floor structure, control and test plans, work safety plan, environment, budget of carcass, economic balance sheet and specialization on concrete structures.
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SIVORI, DANIELE. "Ambient vibration tools supporting the model-based seismic assessment of existing buildings." Doctoral thesis, Università degli studi di Genova, 2021. http://hdl.handle.net/11567/1045713.
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The technological advancements of the last decades are making dynamic monitoring an efficient and widespread resource to investigate the safety and health of engineering structures. In the wake of these developments, the thesis proposes methodological tools supporting the seismic assessment of existing buildings through the use of ambient vibration tests. In this context, the literature highlights considerable room to broaden the ongoing research, especially regarding masonry buildings. The recent earthquakes, once again, highlighted the significant vulnerability of this structural typology as an important part of our built heritage, remarking the importance of risk mitigation strategies for the territorial scale. The thesis builds upon a simplified methodology recently proposed in the literature, conceived to assess the post-seismic serviceability of strategic buildings based on their operational modal parameters. The original contributions of the work pursue the theoretical and numerical validation of its basic simplifying assumptions, in structural modelling – such as the in-plane rigid behaving floor diaphragms – and seismic analysis – related to the nonlinear fundamental frequency variations induced by earthquakes. These strategies are commonly employed in the seismic assessment of existing buildings, but require further developments for masonry buildings. The novel proposal of the thesis takes advantage of ambient vibration data to establish direct and inverse mechanical problems in the frequency domain targeted at, first, qualitatively distinguishing between rigid and nonrigid behaving diaphragms and, second, quantitatively identifying their in-plane shear stiffness, mechanical feature playing a primary role in the seismic behaviour of masonry buildings. The application of these tools to real case studies points out their relevance in the updating and validation of structural models for seismic assessment purposes. In the light of these achievements, a model-based computational framework is proposed to develop frequency decay-damage control charts for masonry buildings, which exploit ambient vibration measurements for quick damage evaluations in post-earthquake scenarios. The results of the simulations, finally, highlight the generally conservative nature of ambient vibration-based simplified methodologies, confirming their suitability for the serviceability assessment of existing masonry buildings.
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Brandtner, Michal. "Stavebně technologický projekt objektu knihovny." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-371803.
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The subject of this final thesis is the building technological project of the library on the street of Kravi hora in the Brno. The final thesis includes a technical report, a coordination situation, a situation of the construction with wider relations with transport route links, a time schedule and financial plan of the construction, a site equipment project, a design of the main machines and mechanisms, a time schedule of the main building object, a supply plan and a plan for transport routes, a technological regulation for cast-in-place floor structure, a control and test plan, a health and safety plan at work on a construction site binding for a carcass, an itemized budget for carcass, a comparison of the solutions for realization of the cast-in-place floor structure and the technological regulation for technology of capture of rainwater for further use.
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Lai, Jing-Ru, and 賴鏡如. "Study on Risk Analysis Framework of Flood Control Structures in Fluvial System." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/94873904632449008382.
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碩士<br>國立交通大學<br>土木工程系所<br>96<br>The purpose of this study is to develop the flood risk assessment framework for flood control structures in fluvial system, including the embankment, dike, groyne and so on. Since the embankments are wildly used to prevent the urban and watershed from flooding, this study focuses on the risk analysis for the flood-control ability of the embankments, which mainly calculates the failure probability of the water level greater than the embankment. The failure probability probably results from the uncertainties of the rainfall depth or flood of specific protection criterions for the design of hydraulic structures, caused by the variation of hydrological, hydraulic and geometrical conditions in the catchments. The proposed risk analysis framework is grouped into four parts, (1) identification and generation of risk factors: using the fault-tree-analysis, the risk factors in the hydrologic and hydraulic routing can be identified, that is hydrological, hydraulic, and geometric factors. The risk factors are generated by Latin hypercubic sampling (LHS) method; (2) estimation of the maximum water levels: the maximum water levels are estimated by the hydrologic and hydraulic analysis with the generated risk factors; (3) establishment of the relationship between the maximum water levels and risk factors: the maximum water levels relationship with risk factors is established by the multi-variates regression analysis; and (4) calculation of the failure probability: the failure probability of the maximum water level greater than embankment is calculated by the risk and uncertainty methods.
In this study, the proposed risk analysis framework is applied in the study area, Keelung river watershed, to evaluate the adequacy of uncertainty methods, the sensitivity of risk factors to the flood control capacity of embankment, and the effect of different freeboards and Yuan-Shan-Zi flood-diversion channel. In view of the results of numerical experiments, the advanced first-order-second-moment (AFOSM) method is more adequate to the risk analysis for the flood control capacity of hydraulic structures in fluvial system, of which the nonlinear relationship between the maximum water levels and risk factors can describe the behavior of the maximum water levels varied with the risk factors. The 200-yr rainfall depth and the maximum dimensionless rainfall ratio are more sensible than remaining risk factors on the flood control ability. Additionally, the freeboards of embankments and Yuan-Shan-Zi flood-diversion channel are able to effectively reduce the failure probability. In summary, the proposed risk analysis framework is demonstrated to be able to be used in the risk analysis for the prevention flood ability of flood-control structures in the river systems. Hence, it is expected the results from the proposed risk analysis framework would be referred in the river treatment and planning.
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Lopes, Pedro. "Free-surface Flow Interface And Air-Entrainment Modelling Using OpenFOAM." 2013. http://hdl.handle.net/10316/24534.
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Projecto de Tese - Programa Doutoral em Eng. Civil<br>The use of hydraulic structures to control flooding has a history of long practice within civil engineering infrastructure. Hydraulic structures under turbulent flow conditions frequently involve free surface fl ow and interactions between air and water. This can be observed in different kinds of structures, e.g. gullies, manholes or stepped spillways. In this doctoral program, Computational Fluid Dynamics numerical models will be used to simulate flood control devices and the results validated using real scale physical models.
The challenge in numerical prediction of air mixed with water is the main motivation for this study. The focus of this work is primarily the air-water interaction and a revision of the numerical models able to capture it. The interFoam solver available in the OpenFOAM Toolbox is chosen as the starting point of this study because it is open-source and widely used to numerically simulate such phenomena. This solver will be thoroughly investigated and some simulations involving air and water will be presented.<br>FCT - Fundação para a Ciência e Tecnologia
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Laisi, Elton. "Development of a flood-frequency model for the river basins of the Central Region of Malawi as a tool for engineering design and disaster preparedness in flood-prone areas." Diss., 2016. http://hdl.handle.net/10500/23597.
Full textAbstract:
Since 1971, a number of flood frequency models have been developed for river basins in
Malawi for use in the design of hydraulic structures, but the varied nature of their results
have most often given a dilemma to the design engineer due to differences in magnitudes
of calculated floods for given return periods. All the known methods for flood frequency
analysis developed in country so far have not used a homogeneity test for the river basins
from which the hydrological data has been obtained. This study was thus conducted with a
view to resolving this problem and hence improve the design of hydraulic structures such
as culverts, bridges, water intake points for irrigation schemes, and flood protection dykes.
In light of the above, during the course of this study the applicability of existing methods
in the design of hydraulic structures was assessed. Also, the study investigated how land
use and land cover change influence the frequency and magnitude of floods in the study
area, and how their deleterious impacts on the socio-economic and natural environment in
the river basins could be mitigated<br>Environmental Sciences<br>M. Sc. (Environmental Management)
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Chandrasekharan, Diji. "Structural flood control investments the impact of information and irreversibility /." 1994. http://catalog.hathitrust.org/api/volumes/oclc/32777476.html.
Full textAbstract:
Thesis (M.S.)--University of Wisconsin--Madison, 1994.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves , 82-85).
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Slater, Alyson. "Non structural flood mitigation in Canada : linking the resources of today with a strategy for tomorrow." Thesis, 2000. http://hdl.handle.net/2429/10505.
Full textAbstract:
Flooding poses one of the greatest natural hazard dangers to Canadians. As human
populations increase and concentrate in areas vulnerable to floods, and uncertainty about
future flood risk increases with the possibility of a changing climate, major urban
communities, coastal settlements and communities located within floodplains are faced with
an even greater risk of floods in the coming years. Canada's policies and practices
towards flood control are best described as ad hoc, and have developed over the years in
response to experiences with floods. No national scale flood damage reduction program
exists, and there is currently no opportunity for Canadian homeowners to purchase flood
insurance.
This study specifically examines how a national mitigation strategy, focused mainly on non
structural techniques could help decrease damages from floods in Canadian communities.
The strategy proposed here is theoretically based in EPC and IBC suggestions for a greater
national mitigation strategy, as well as IDNDR research, and federal, provincial and
municipal goals for sustainable development and sound land use planning objectives.
Ideally, a successful non structural flood mitigation strategy for Canada would address
issues at the national scale, yet be implementable at the local level in accordance with
community needs, risk characteristics, and local expertise. The strategy proposed here
would maximize the efficiency of federal resources and private industry as well as allow
local expertise and existing mitigation schemes to be formalized, bolstered and improved.
There are three major components of the non structural flood mitigation strategy. Risk
avoidance measures such as early warning systems, land use and resource planning and
ecological conservation all work towards reducing the chances of a dangerous flood
occurring. Risk spreading measures help communities deal with flood risks by improving
equity and accountability, they include tax incentives, disaster financial assistance, and
flood insurance. Lastly, vulnerability reduction measures help reduce damages if a flood
were to strike, and these include enforcement of building codes and the maintenance of
existing protective infrastructure.
An integrated, non structural flood mitigation strategy would require basin-wide cooperation
between all levels of government, citizens and the private sector. This strategy is also an
opportunity for communities and individuals to meet goals of environmental conservation
and sustainable development.
The focus in this study lies on the mitigation tools, although it is the overall process of
inserting the premise of mitigation into all land use and planning decision making processes
that will be the key to successful flood mitigation strategies in Canadian communities.