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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Sanace sesuvu silničního tělesa / Stabilization of landslide on road embankment

Kořínková, Jana January 2018 (has links)
The topic of this Master`s thesis is to design stabilization of road embankment, which is between Brno-Chrlice and Brno-Holásky. Aim of this thesis is finding acceptable solution of problem including finding cause of fault and describing other possible options. Solution will be design in GEO5. Thesis is completed with procedure in pile installation and drawing documentation.
262

Analýza způsobu vedení trasy přes sesuvné území dálnice D1 ve SR / Analysis of the way of the route through the sloping area of the D1 motorway in the SR

Horňáková, Lenka January 2019 (has links)
The construction of motorways in Slovakia faces a series of geotechnical problems due to the mountainous relief. One of these problems is also discussed in this diploma thesis, where the motorway route is led through a landslide area. The aim of the thesis is to compare two different proposals of the D1 motorway in part of Hubova - Ivachnova section. The theoretical part deals with the issue of slope movements in connection with transport line constructions. In the practical part, the proposals for specific solutions of the high embankment route variant and variant with the bridge are discussed. Both variants are designed in the Plaxis numeric program. Subsequent comparison and evaluation of variants is performed in relation to the degree of stability, deformation, structural stress and construction costs.
263

Návrh založení dálničního mostu / The Design of Highway Bridge Foundations

Králík, Michal January 2019 (has links)
Topic of this master`s thesis is founding of the hightway bridge, which is located between Lipník and Bělotín. Thesis is aimed for creating shallow foundation and foundation on piles and choosing which option is better. All evaluations have been made without specialized software and than compared with GEO5 results. Better solution will be completed with procedure for construction and drawing documentation.
264

Geotechnisches Monitoring am Beispiel statisch axialer, horizontaler und bi-direktionaler Pfahlprobebelastungen in Baku, Aserbaidschan

Papmeyer, Falk, Ulbricht, Falk, England, Melvin January 2016 (has links)
Im Anschluss an die von der Fugro Consult GmbH durchgeführte geotechnische Baugrunderkundung für die geplante Erweiterung eines Öl- und Gasterminals im Sangachal Distrikt südlich von Baku, Aserbaidschan, wurde durch die Fugro Consult GmbH in Zusammenarbeit mit Fugro Loadtest ein geotechnisches Monitoring-Programm in Form von Pfahlprobebelastungen durchgeführt und in diesem Zusammenhang verschiedene statische Zustände simuliert. Neben Vertikallasten, den Hauptlasten aus den zukünftigen Bauwerken, wurden auch horizontale Lasten am Pfahlkopf aufgetragen und mit verschiedenen Monitoring-Methoden während der Versuchsdurchführung überwacht. Das Monitoring-Programm wurde in zwei Feldkampagnen durchgeführt. In der ersten Kampagne wurden Probepfähle an ausgewählten Lokationen bis zum Versagen belastet, um Grenzzustände zu ermitteln, das Pfahldesign zu optimieren und die in der Baugrunderkundung ermittelten geotechnischen Parameter zu überprüfen. In einer zweiten Kampagne wurden dann Bauwerkspfähle getestet, um die Qualität der Pfahlherstellung zu prüfen und die vom Statiker vorgegebenen zulässigen Setzungen der Pfähle unter der geplanten Bauwerkslast zu kontrollieren. / Following the geotechnical site investigation for the extension of the Oil- and Gas terminal in the Sangachal district, south of Baku, Azerbaijan performed by Fugro Consult GmbH a comprehensive pile monitoring program was performed subsequently by Fugro Consult GmbH in collaboration with Fugro Loadtest. The monitoring program comprised full scale static axial, lateral and bi-directional pile load tests using the O-cell® method. Beside vertical loads induced by the future building, also lateral loads were applied and monitored by means of different monitoring methods. The monitoring Program was performed in two field campaigns. During the first campaign only preliminary piles were loaded until failure in order to determine the ultimate limit state, to optimize the pile design and to verify the geotechnical parameter acquired during the preceding site investigation. During the second field campaign only working piles were tested to assure constant quality during pile installation and to confirm that allowable settlements stipulated by the designer are not exceeded.
265

Der Einsatz unbemannter Flugsysteme zur Charakterisierung von gesprengtem Haufwerk

Tscharf, Alexander, Mostegel, Christian, Gaich, Andreas, Mayer, Gerhard, Fraundorfer, Friedrich, Bischof, Horst January 2017 (has links)
Die erreichte Zerkleinerung und die Form des Haufwerks sind die beiden wichtigsten Ergebnisse einer Tagebausprengung. Schnelle Informationen über die Eigenschaften des gesprengten Haufwerks ermöglichen eine zielgerichtete und effiziente Produktionsplanung und Kenntnisse über die erreichte Zerkleinerung ermöglichen außerdem Anpassungen in der weiteren Zerkleinerungskette. Durch den Einsatz von UAVs (unmanned aerial vehicles) gemeinsam mit modernen Algorithmen aus dem Bereich Computer Vision und des maschinellen Lernens soll eine schnelle Erfassung und Interpretation der Daten bei gleichzeitiger Integration in die herkömmlichen betrieblichen Abläufe ermöglicht werden, und außerdem können Schwächen bodengebundener Systeme hinsichtlich Vollständigkeit und Repräsentativität umgangen werden. Im vorliegenden Beitrag wird einerseits auf den relevanten Stand des Wissens und der Technik eingegangen und andererseits wird die verfolgte Stoßrichtung bei der Systementwicklung dargelegt sowie erste Arbeiten präsentiert. / The fragmentation and the shape of the muck pile are the two major outcomes of open pit mine and quarry blasts. Fast information about the muck pile properties will help to improve the production scheduling and furthermore this information could be used to optimize the blasting patterns of future production blasts. The combined use of unmanned aerial vehicles (UAVs) and modern machine learning and computer vision systems offers a new way of acquiring spatial data to determine on-site fragment size distribution, while at the same time enabling integration into common work flows and mitigating the weaknesses of ground-based systems with special regard to completeness and representativeness. In the present paper, we will discuss the relevant related work, present the planned path for system development and give examples of first work.
266

Design and execution of energy piles : Validation by in-situ and laboratory experiments / Dimensionnement et exécution de pieux énergétiques : Validation par essais in-situ et en laboratoire

Vasilescu, Andreea-Roxana 08 July 2019 (has links)
Les pieux énergétiques représentent une solution alternative intéressante, face à l’accroissement des besoins mondiaux en énergie et à la réduction de l’utilisation des énergies fossiles. L’objectif principal de la thèse est d’identifier et de quantifier les principaux facteurs influençant le dimensionnement des pieux géothermiques, qui sont impactés par les changements de température des pieux lors de leur activité. Pour ce faire, ce travail de thèse a été dressé en 3 campagnes expérimentales, dont deux à échelle réelle : (i) une première campagne à chargement thermomécanique contrôlé (Marne La Vallée), (ii) une seconde campagne en conditions d’utilisation réelles sous une station d’épuration (Sept Sorts) et (iii) une troisième campagne à l’échelle du laboratoire grâce à une nouvelle machine de cisaillement direct d’interface permettant l’étude du comportement thermo mécanique des interfaces sol-structure. Ces trois campagnes expérimentales ont pour but de quantifier l’effet de la température et des cycles de température sur le comportement des pieux énergétiques. Les premiers résultats expérimentaux de la campagne de Sept Sorts ont ensuite été simules dans le code LAGAMINE via la méthode des éléments finis, afin d’adopter une approche complémentaire permettant de mieux appréhender la réponse thermomécanique de ce type de pieu lors de l’activation géothermique. et (iii) une troisième campagne à l’échelle du laboratoire grâce à une nouvelle machine de cisaillement direct d’interface permettant l’étude du comportement thermo mécanique des interfaces sol-structure. Ces trois campagnes expérimentales ont pour but de quantifier l’effet de la température et des cycles de température sur le comportement des pieux énergétiques. Les premiers résultats expérimentaux de la campagne de Sept Sorts ont ensuite été simules dans le code LAGAMINE via la méthode des éléments finis, afin d’adopter une approche complémentaire permettant de mieux appréhender la réponse thermomécanique de ce type de pieu lors de l’activation géothermique. / Energy piles, also called thermo-active piles, are an alternative solution to the increase in the global energy demand as well as in mitigating socio-economical stakes concerning the increase of energy costs due to fossil fuels. Energy piles are double purpose structures that allow transferring the loads from the superstructure to the soil and that integrate pipe circuits allowing heat exchange between the pile and the surrounding ground. The objective of this thesis is to identify and quantify the principal parameters involved in the geotechnical design of pile foundations impacted by temperature changes associated with geothermal activation. For this purpose, this research work was organized in 3 experimental campaigns: (i) A full scale load controlled test at Ecole des Ponts Paris-Tech, (ii) Full scale energy piles monitoring under real exploitation conditions at Sept Sorts, (Seine et Marne, France), (iii) Laboratory tests in order to assess the effect of temperature and temperature cycles at the soil-pile interface. The experimental results are used to estimate the effect of geothermal activation of a pile foundation, on its bearing capacity as well as on its long-term exploitation. Finally, preliminary numerical simulations were performed using a thermo-hydro mechanical model, using the finite element method code LAGAMINE able to capture the main phenomena.
267

Lateral Resistance of 24-inch Statically Loaded and 12.75-Inch Cyclically Loaded Pipe Piles Near a 20-ft Mechanically Stabilized Earth (MSE) Wall

Wilson, Addison Joseph 03 December 2020 (has links)
Installing load bearing piles within the reinforcement zone of mechanically stabilized earth (MSE) retaining walls is common practice in the construction industry. Bridge abutments are often constructed in this manner to adapt to increasing right-of-way constraints, and must be capable of supporting horizontal loads imposed by, traffic, earthquakes, and thermal expansion and contraction. Previous researchers have concluded that lateral pile resistance is reduced when pile are placed next to MSE walls but no design codes have been established to address this issue. Full –scale testing of statically applied lateral loads to four 24”x0.5” pipe piles, and cyclically applied lateral load to four 12.75”x0.375” pipe piles placed 1.5-5.3 pile diameters behind a 20-foot MSE wall was performed. The MSE wall was constructed using 5’x10’ concrete panels and was supported with ribbed strip and welded wire streel reinforcements. The computer software LPILE was used to back-calculate P-multipliers for the 24” piles. P-multipliers are used to indicate the amount of reduction in lateral resistance the piles experience due to their placement near the MSE wall. Previous researchers have proposed that any pile spaced 3.9 pile diameters (D) or more away from the MSE wall will have a P-multiplier of 1; meaning the pile experiences no reduction in lateral resistance due to its proximity to the wall. P-multipliers for piles spaced closer than 3.9D away from the wall decrease linearly as distance from the wall decreases. P-multipliers for the 24” piles spaced 5.1D, 4.1D, 3.0D, and 2.0D were 1, 0.84, 0.55, and 0.44 respectively. Lateral resistance of the 12.75” cyclically loaded piles decreased as the number of loading cycles increased. Lateral resistance of the piles when loads were applied in the direction of the wall was less than the lateral resistance of the piles when loads were applied away from the wall at larger pile head loads. The maximum tensile force experienced by the soil reinforcements generally occurred near the wall side of the pile face when the lateral loads were applied in the direction of the wall. Behind the pile, the tensile force decreased as the distance from the wall increased. Equation 5-4, modified from Rollins (2018) was found to be adequate for predicting the maximum tensile force experienced by the ribbed strip reinforcements during the static loading of the 24” pipe piles, particularly for lower loads. About 65% of the measured forces measured in this study fell within the one standard deviation boundary of the proposed equation.
268

Ground Vibrations due to Vibratory Sheet Pile Driving

Lidén, Märta January 2012 (has links)
Vibratory driving is today the most common installation method of sheet piles. The knowledge of the induced ground vibrations is however still deficient. This makes predictions of the vibration magnitudes difficult to carry out with good reliability. To avoid exceeding the limit values, resulting in stops of production, or that vibratory driven sheet piles are discarded for more costly solutions, a need for increased knowledge of the vibration process is imminent. With increased knowledge, a more reliable and practical prediction model can be developed.  The aim of this thesis is to analyze measured data from a field study to increase the understanding of the induced vibrations and their propagation through the soil. The field study was performed in Karlstad in May 2010, where a trial sheet piling prior to an extension of Karlstad Theatre was carried out. During the trial sheet piling, two triaxial geophones were mounted at the ground surface at two different distances from the sheet piles, to measure the vibration amplitude. The field test is associated with some limitations. Only four sheet piles were driven, with one measurement per sheet pile. Some measurements were less successful and some parameters had to be assumed. This limits the accuracy but still provides some interesting results. Another aim is to compare the measured values to existing models for predicting vibrations from piling and sheet piling operations. There are today several prediction models available, which however often provide too crude estimations or alternatively are too advanced to be incorporated in practical use. Two basic empirical prediction models are compared to the measured values in Karlstad, where the first is one of the earliest and most well known models and the other is a later development of the first model. The purpose of this comparison is to evaluate these models to contribute to the development of a new prediction model. The results show that the earlier model greatly overestimates the vibration magnitude while the later developed model provides a better estimation.  A literature study is performed to gain a theoretical background to the problem of ground vibrations and how they are related to the method of vibratory driving of sheet piles. The analysis considering the field study and prediction models is mainly performed by using MATLAB to obtain different graphical presentations of the vibration signals. The conclusions that can be drawn from the results are that the focus of vibration analysis should not always be the vertical vibration components. Horizontal movements of the sheet pile might be introduced, e.g. by the configuration of the clamping device, which generates additional vibrations in horizontal directions. The soil characteristics influence the magnitude of the vibrations. As the sheet pile reaches a stiffer soil layer, the vibration magnitude increases. A realistic and reliable prediction model should take the characteristics of the soil into account.
269

Let us be the second body

Herrmann, Cilia January 2021 (has links)
The essay Let us be the second body is a written pensive and companion in the process of creating a performance with the same title performed in January 2021 at SKH in Stockholm. It describes the main task of the project which was about realizing interdependencies, in a search for political movement towards a non-violent way of relating with and within the world. In the essay, it is described how this can be imagined like crawling through a compost pile. What you find digesting in the pile are conversations and encounters with strangers on the street such as Blurry-Believes/ Pretend-Poems/ Slippery-Statements, and composed fragments of thoughts from thinkers like Maria Lugones, Judith Butler, Ta-Nehsi Coates, and Michael Ende. Composing those fragments within this essay is forming the sentence: “I cannot be out of violence until the system that I am living in is, even though I am not the target of that violence. The essay is longing to get into the muddy work of investigating the concepts of ‘transformation’ and ‘change’. A work that is meant to be, as the structure of the text, mirrored, messed up and ambiguous.  (And through being honest in that ambiguity the essay regains a response-ability.) Concretely, the essay reflects on how I use this ambiguity as a tool for creating the performance Let us be the second body, in which textile art, scenography, sound design and dancing linger in interdependence with the realm of transformation. I will and I will not change the world with this essay. So, I guess you will and you will not be changed by this essay. / <p>This master work includes both a performing and a written part.</p>
270

Three-Dimensional Finite Element Analysis of the Pile Foundation Behavior in Unsaturated Expansive Soil

Wu, Xingyi 22 April 2021 (has links)
Expansive soils, which are widely referred to as problematic soils are extensively found in many countries of the world, especially in semi-arid and arid regions. Several billions of dollars are spent annually for maintenance or for repairs to the structures constructed with and within expansive soils. The major problems of expansive soils can be attributed to the volume changes associated with the alternate wetting and drying conditions due to the influence of environmental factors. Pile foundations have been widely accepted by practicing engineers as a reasonably good solution to reduce the damages to the structures constructed on expansive soils. Typically, piles foundations are extended through the active layer of expansive soil to reach the bedrock or placed on a soil-bearing stratum of good quality. Such a design and construction approach typically facilitates pile foundations to safely carry the loads from the superstructures and reduce the settlement. However, in many scenarios, damages associated with the pile foundations are due to the expansion of the soil that is predominantly in the active zone that contributes to the pile uplift. Such a behavior can be attributed to the water infiltration into the expansive soil, which is a key factor that is associated with the soil swelling. Due to this phenomenon, expansive soil typically moves upward with respect to the pile. This generates extra positive friction on the pile because of the relative deformation. If the superstructure is light or the applied normal stress on the head of the piles is not significant, it is likely that there will be an uplift of the pile contributing to the damage of the superstructure. In conventional engineering practice, the traditional design methods that include the rigid pile method and the elastic pile method are the most acceptable in pile foundation design. These methods are typically based on a computational technique that uses simplified assumptions with respect to soil and water content profile and the stiffness and shear strength properties. In other words, the traditional design method has limitations, as they do not take account of the complex hydromechanical behavior of the in-situ expansive soils. With the recent developments, it is possible to alleviate these limitations by using numerical modeling techniques such as finite element methods. In this thesis, a three-dimensional finite element method was used to study the hydro-mechanical behavior of a single pile in expansive soils during the infiltration process. In this thesis, a coupled hydro-mechanical model for the unsaturated expansive soil is implemented into Abaqus software for analysis of the behavior of single piles in expansive soils during water infiltration. A rigorous continuum mechanics based approach in terms of two independent stress state variables; namely, net normal stress and suction are used to form two three-dimensional constitutive surfaces for describing the changes in the void ratio and water content of unsaturated expansive soils. The elasticity parameters for soil structure and water content in unsaturated soil were obtained by differentiating the mathematical equations of constitutive surfaces. The seepage and stress-deformation of expansive soil are described by the coupled hydro-mechanical model and the Darcy’s law. To develop the subroutines, the coupled hydro-mechanical model is transferred into the coupled thermal-mechanical model. Five user-material subroutines are used in this program. The user-defined field subroutine (USDFILD) in Abaqus is used to change and transfer parameters. Three subroutines including user-defined material subroutine (UMAT), user-defined thermal material subroutine (UMATHT), and user-defined thermal expansion subroutine (UEXPAN) are developed and used to calculate the stress-deformation, the hydraulic behavior, and the expansion strain, respectively. Except for the coupled hydro-mechanical model of unsaturated expansive soils, a soil-structure interface model is implemented into the user-defined friction behavior subroutine (FRIC) to calculate the friction between soil and pile. The program is verified by using an experimental study on a single pile in Regina clay. The results show that for the single pile in expansive soil under a vertical load, water infiltration can cause a reduction in the pile shaft friction. More pile head load is transferred to the pile at greater depth, which increases the pile head settlement and pile base resistance. In future, the proposed method can also be extended for verification of other case studies from the literature. In addition, complex scenarios can be investigated to understand the behavior of piles in expansive soils.

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