967 resultados para Piling (Civil engineering)


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This paper deals with the problem of semiactive vibration control of civil engineering structures subject to unknown external disturbances (for example, earthquakes, winds, etc.). Two kinds of semiactive controllers are proposed based on the backstepping control technique. The experimental setup used is a 6-story test structure equipped with shear-mode semiactive magnetorheological dampers being installed in the Washington University Structural Control and Earthquake Engineering Laboratory (WUSCEEL). The experimental results obtained have verified the effectiveness of the proposed control algorithms

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A previous study sponsored by the Smart Work Zone Deployment Initiative, “Feasibility of Visualization and Simulation Applications to Improve Work Zone Safety and Mobility,” demonstrated the feasibility of combining readily available, inexpensive software programs, such as SketchUp and Google Earth, with standard two-dimensional civil engineering design programs, such as MicroStation, to create animations of construction work zones. The animations reflect changes in work zone configurations as the project progresses, representing an opportunity to visually present complex information to drivers, construction workers, agency personnel, and the general public. The purpose of this study is to continue the work from the previous study to determine the added value and resource demands created by including more complex data, specifically traffic volume, movement, and vehicle type. This report describes the changes that were made to the simulation, including incorporating additional data and converting the simulation from a desktop application to a web application.

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Résumé La réalisation d'une seconde ligne de métro (M2) dès 2004, passant dans le centre ville de Lausanne, a été l'opportunité de développer une méthodologie concernant des campagnes microgravimétriques dans un environnement urbain perturbé. Les corrections topographiques prennent une dimension particulière dans un tel milieu, car de nombreux objets non géologiques d'origine anthropogénique comme toutes sortes de sous-sols vides viennent perturber les mesures gravimétriques. Les études de génie civil d'avant projet de ce métro nous ont fournis une quantité importante d'informations cadastrales, notamment sur les contours des bâtiments, sur la position prévue du tube du M2, sur des profondeurs de sous-sol au voisinage du tube, mais aussi sur la géologie rencontré le long du corridor du M2 (issue des données lithologiques de forages géotechniques). La planimétrie des sous-sols a été traitée à l'aide des contours des bâtiments dans un SIG (Système d'Information Géographique), alors qu'une enquête de voisinage fut nécessaire pour mesurer la hauteur des sous-sols. Il a été alors possible, à partir d'un MNT (Modèle Numérique de Terrain) existant sur une grille au mètre, de mettre à jour celui ci avec les vides que représentent ces sous-sols. Les cycles de mesures gravimétriques ont été traités dans des bases de données Ac¬cess, pour permettre un plus grand contrôle des données, une plus grande rapidité de traitement, et une correction de relief rétroactive plus facile, notamment lorsque des mises à jour de la topographie ont lieu durant les travaux. Le quartier Caroline (entre le pont Bessières et la place de l'Ours) a été choisi comme zone d'étude. Le choix s'est porté sur ce quartier du fait que, durant ce travail de thèse, nous avions chronologiquement les phases pré et post creusement du tunnel du M2. Cela nous a permis d'effectuer deux campagnes gravimétriques (avant le creu¬sement durant l'été 2005 et après le creusement durant l'été 2007). Ces réitérations nous ont permis de tester notre modélisation du tunnel. En effet, en comparant les mesures des deux campagnes et la réponse gravifique du modèle du tube discrétisé en prismes rectangulaires, nous avons pu valider notre méthode de modélisation. La modélisation que nous avons développée nous permet de construire avec détail la forme de l'objet considéré avec la possibilité de recouper plusieurs fois des interfaces de terrains géologiques et la surface topographique. Ce type de modélisation peut s'appliquer à toutes constructions anthropogéniques de formes linéaires. Abstract The realization of a second underground (M2) in 2004, in downtown Lausanne, was the opportunity to develop a methodology of microgravity in urban environment. Terrain corrections take on special meaning in such environment. Many non-geologic anthropogenic objects like basements act as perturbation of gravity measurements. Civil engineering provided a large amount of cadastral informations, including out¬lines of buildings, M2 tube position, depths of some basements in the vicinity of the M2 corridor, and also on the geology encountered along the M2 corridor (from the lithological data from boreholes). Geometry of basements was deduced from building outlines in a GIS (Geographic Information System). Field investigation was carried out to measure or estimate heights of basements. A DEM (Digital Elevation Model) of the city of Lausanne is updated from voids of basements. Gravity cycles have been processed in Access database, to enable greater control of data, enhance speed processing, and retroactive terrain correction easier, when update of topographic surface are available. Caroline area (between the bridge Saint-Martin and Place de l'Ours) was chosen as the study area. This area was in particular interest because it was before and after digging in this thesis. This allowed us to conduct two gravity surveys (before excavation during summer 2005 and after excavation during summer 2007). These re-occupations enable us to test our modélisation of the tube. Actually, by comparing the difference of measurements between the both surveys and the gravity response of our model (by rectangular prisms), we were able to validate our modeling. The modeling method we developed allows us to construct detailed shape of an object with possibility to cross land geological interfaces and surface topography. This type of modélisation can be applied to all anthropogenic structures.

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In 1994 the Iowa Department of Transportation constructed a 7.2-mile Portland Cement Concrete overlay project in Iowa County on Iowa Highway 21. The research work was conducted in cooperation with the Department of Civil Engineering and the Federal Highway Administration under the Iowa Highway Research Board project HR-559. The project was constructed to evaluate the performance of an ultrathin concrete overlay during a 5-year period. The experiment included variables of base surface preparation, overlay depth, joint spacing, fiber reinforcement, and the sealed or non-sealed joints. The project was instrumented to measure overlay/base interface temperatures and strains. Visual distress surveys and deflection testing were also used to monitor performance. Coring and direct shear testing was accomplished 3 times during the research period. Results of the testing and monitoring are identified in the report. The experiment was very successful and the results provide an insight into construction and design needs to be considered in tailoring a portland cement concrete overlay to a performance need. The results also indicate a method to monitor bond with nondestructive methods.

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The research of condition monitoring of electric motors has been wide for several decades. The research and development at universities and in industry has provided means for the predictive condition monitoring. Many different devices and systems are developed and are widely used in industry, transportation and in civil engineering. In addition, many methods are developed and reported in scientific arenas in order to improve existing methods for the automatic analysis of faults. The methods, however, are not widely used as a part of condition monitoring systems. The main reasons are, firstly, that many methods are presented in scientific papers but their performance in different conditions is not evaluated, secondly, the methods include parameters that are so case specific that the implementation of a systemusing such methods would be far from straightforward. In this thesis, some of these methods are evaluated theoretically and tested with simulations and with a drive in a laboratory. A new automatic analysis method for the bearing fault detection is introduced. In the first part of this work the generation of the bearing fault originating signal is explained and its influence into the stator current is concerned with qualitative and quantitative estimation. The verification of the feasibility of the stator current measurement as a bearing fault indicatoris experimentally tested with the running 15 kW induction motor. The second part of this work concentrates on the bearing fault analysis using the vibration measurement signal. The performance of the micromachined silicon accelerometer chip in conjunction with the envelope spectrum analysis of the cyclic bearing faultis experimentally tested. Furthermore, different methods for the creation of feature extractors for the bearing fault classification are researched and an automatic fault classifier using multivariate statistical discrimination and fuzzy logic is introduced. It is often important that the on-line condition monitoring system is integrated with the industrial communications infrastructure. Two types of a sensor solutions are tested in the thesis: the first one is a sensor withcalculation capacity for example for the production of the envelope spectra; the other one can collect the measurement data in memory and another device can read the data via field bus. The data communications requirements highly depend onthe type of the sensor solution selected. If the data is already analysed in the sensor the data communications are needed only for the results but in the other case, all measurement data need to be transferred. The complexity of the classification method can be great if the data is analysed at the management level computer, but if the analysis is made in sensor itself, the analyses must be simple due to the restricted calculation and memory capacity.

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Diplomityön tavoitteena oli kehittää Andritzin Kuitulinja-divisioonalle tunnuslukuja, työkaluja sekä menetelmiä projektin johdon jasuunnittelun eri osa-alueiden arviointiin, hinnoitteluun ja seurantaan Työn teoriaosuudessa käsiteltiin projektiliiketoimintaa, suunnitteluaja sen hankintaa, tunnuslukuja sekä mittaamista projektiympäristössä. Työn pääpaino oli kuitenkin empiriaosuudella, jossa aluksi tutustuttiin yksityiskohtaisesti työssä tutkittaviin osa-alueisiin. Tiedonkeruuvaiheessa kerättiin suuri määrätunnuslukujen laskemiseksi tarvittavaa tietoa toteutetuista tai vielä hieman keskeneräisistä projekteista. Työn kirjallinen osuus ja kerätty numeerinen tieto yhdistettiin tunnuslukujen analysointivaiheessa, jossa tutkittiin eri tunnuslukujen soveltuvuutta mittaamiseen. Tunnusluvut soveltuivat hyvin joidenkin osa-alueiden kuten prosessi- ja putkistosuunnittelun mittaamiseen. Joidenkin osa-alueiden, kuten rakennussuunnittelun mittaaminen tunnuslukujen avulla oli vaikeampaa tunnuslukujen suuresta hajonnasta johtuen. Eri osa-alueille saatiin kuitenkin määritettyä parhaat tunnusluvut, projektien luokitteluperusteet ja standardiarvot. Työn lopputuloksina saatiin päätavoitteena ollut tunnuslukumittaristo sekä mittaamisen yhtenäistämiseksi luotu tiedonkeruulomake. Mittaamisen tehostamiseksi ja kehittämiseksi tehtiin useita jatkotutkimus- ja kehitysehdotuksia. Lisäksi työssä esitettiin uusi menetelmä projektinohjauksen ja resurssisuunnittelun tueksi.

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Useilla toimialoilla kuten infra-alalla verkostoituminen on ollut vieras käsite. Hankintamallit, lainsäädäntö ja alalle ominaiset lyhytkestoiset projektit ovat olleet kumppanuuksien esteenä. Uudet hankintamallit ja toimijoille asetetut roolijakovaatimukset antavat infra-toimialan yrityksille mahdollisuuksia kumpanuuksien rakentamiseen. Tutkimuksen tavoitteena on löytää syitä ja motiiveja jotka johtavat verkostoitumiseen infra-alalla. Tutkimuksessa esitellään verkostoitumisen näkökulmasta käsin infra-alan keskeisen rakennuttaja-organisaation hankintastrategiaa, sekä siitä muodostettua alan arvoketjua. Verkostoituminen on prosessi, jonka aikana arvioidaan yrityksen kykyä toimia kumppanina. Vertikaalisen verkostoitumisen haasteena on yritysten välille syntyvä yhteinen näkemys toimintatavoista, joilla kahdenvälinen markkinaehtoinen liikesuhde voidaan muuttaa kumppanuudeksi. Tavoitteena on oikean tasapainon löytäminen hyötyjen ja haittojen välillä. Tutkimuksessa esitellään niitä hyötyjä ja haittoja, jotka liittyvät yritystenväliseen vertikaalisen verkostoitumiseen. Tutkimuksessa esitellään myös kaksi valmista verkostoitumistyökalua, jotka on tarkoitettu yritysten käyttöön verkostoitumisprosessin tueksi. Työkalut on valittu siten, että niiden käyttäminen on mahdollista ja hyödyllistä heti verkostoitumisprosessin alku- eli rakennusvaiheessa.

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En este artículo se da a conocer la información disponible sobre la construcción de una acequia en el lugar de Aldover, perteneciente al término general de la ciudad de Tortosa, en los primeros años del siglo XV. Especialmente, se resalta la importancia que tuvieron esta y otras obras alejadas de la 'gran' arquitectura de la época en el trabajo de los maestros de la construcción de la Edad Media y la Moderna. En este caso, destaca la participación de Antoni Queralt, oriundo de la Espluga Calba y maestro mayor de las catedrales de Tortosa y Lleida

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La cita que sirve de título a este epígrafe introductorio es del picapedrero aragonés Sebastián Martínez. Forma parte de un informe, redactado en 1556, sobre la construcción de una acequia en el margen izquierdo del Ebro. Y parece ser que pese a la voluntad del maestro muy poca gente, experta o no en el arte del"livell", ha sentido la necesidad de conocer las conclusiones de su estudio, como tampoco se ha sentido apenas la necesidad de estudiar el proceso constructivo del sistema de riego del curso bajo de este río, conocimiento o, más bien, desconocimiento anclado durante muchos años en las teorías que relacionaban su erección con la tecnología de época andalusí.

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This thesis examines the effectiveness of non-coercive influence tactics in the context of consumer online behaviour. The objective of this study is to develop a comprehensive understanding of consumer online behaviour and the role of information types in affecting the consumer’s cognitive responses and behavioural outcomes. The theoretical part of the study examines the academic literature on consumer online behaviour and influence tactics used both in traditional buyer/seller relationships as well as in relationships mediated by online technologies. The empirical part of the study is carried out with four experiments that utilise non-coercive influence tactics to affect online consumer behaviour. The consumers included in this study are 18-28 year-old structural and civil engineering students in Finland, United Kingdom, United States and India. The findings suggest that non-coercive influence tactics are applicable in the online marketing context and generate cognitive responses of site awareness, site involvement and exploratory behaviour which subsequently results in behavioural outcomes of compliance, eWOM and site abandonment.

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Työn tavoitteena on tarkastella erilaisia in-situ -kunnostusmenetelmiä maaperän ja pohjaveden kunnostushankkeissa ja niiden toteutusvaihtoehtoja sekä vertailla niitä keskenään. Työssä tarkastellaan myös lainsäädännön ja eri menetelmien kehittymistä, niiden tulevaisuuden näkymiä sekä pohditaan yrityksen tuotteiden liiketoimintamahdollisuuksia tämän pohjalta. Tietoa kerätään kirjallisuudesta sekä tapaustutkimuksista ja niitä peilataan yrityksen sisällä olevaan hiljaiseen tietoon. Löydettyä kirjallisuustietoa sekä tapaustutkimuksia on analysoitu SWOT-analyysien sekä ryhmittelyjen avulla. Työn tuloksena on esitetty vaihtoehtoinen tapa asentaa reaktiivinen seinämä pohjaveden kunnostushankkeissa yrityksen tuotteiden ja putkipaalujen avulla. Lisäksi työn pohjalta voidaan koota materiaalia ja lisätietoa asiakkaille sekä myynnin ja markkinoinnin tukemiseen. Tulosten pohjalta voidaan arvioida, että kyseinen menetelmä tukisi myös kestävän kehityksen periaatteita kunnostushankkeen toteutus- ja asennusvaiheessa. Menetelmän avulla voitaisiin mahdollisesti vähentää reaktiivisten seinämien asentamiseen liittyviä ympäristövaikutuksia.

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Roberta “Bobbie” Styran was born and rasied in Fredericton, N.B. She graduated from McMaster University with a B.A. (1962) and M.A. (1964), before furthering her studies at the University of Toronto, where she received a Ph. D in History. From 1967 to 1978, she taught Medieval History at Brock University, where she developed an interest in the Welland Canal. She began a collaboration with Prof. Robert R. Taylor of the History Department at this time, researching the history of the Welland Canals. She later moved to Toronto and worked for the Ministry of Education, but returned to St. Catharines in 1988 to facilitate her work with Prof. Taylor. The two have co-authored several books, including The Welland Canals: the Growth of Mr. Merritt’s Ditch; Mr. Merritt’s Ditch: A Welland Canals Album; The Great “Swivel Link”: Canada’s Welland Canal and This Great National Object: Building the Nineteenth-Century Welland Canals. Bobbie travelled extensively, visiting many canal and industrial revolution sites in Great Britain and the United States. She was active in many canal associations, including the Canadian Canal Society (where she served as president and editor of the Society’s newsletter), the American Canal Society, and the Council of Inland Waterways International. She also helped to found the Welland Canals Preservation Association and organized and chaired the 2004 World Canals Conference at Brock University. In 2009, she received the W. Gordon Plewes Award from the Canadian Society for Civil Engineering, an award that recognized her services to Canadian engineering history.