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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.
21

Inžinerinių tinklų įrengimas horizontalaus valdomo gręžimo metodu / Engineering networks horizontal directional drilling fitting approach

Šiaulys, Tomas 03 June 2009 (has links)
Darbe analizuojama inžinerinių tinklų įrengimas horizontalaus valdomo gręžimo metodu. Pirmiausia pateikiama literatūros apžvalga, kurioje aptariami veiksniai, lemiantys žemės kasimo darbus. Aprašomas atviras žemės kasimo būdas, kuris dažniausiai naudojamas atliekant žemės kasimo darbus. Aptariamos betranšėjės technologijos, kurios naudojamos kaip alternatyva atviram žemės kasimo būdui specifinėse vietose. Tyrimo metodikoje ir organizavime dalyje pateikiami gręžimo darbų projektai bei jų analizės, gręžimo darbų pasirengimo etapai, gręžimo mašinų ir kitos įrangos, naudojamos tyrime, charakteristikos. Aptariami gręžimo mašinų parinkimo metodai konkrečiam gręžimui ir aprašomi gręžimo darbai. Tyrimų rezultatų analizės dalyje pateikiama gręžimo mašinų charakteristikų analizė bei pasirinktų trijų gręžimų ,,Kryptinio gręžimo matavimo protokolai“ bei pagal juos sudaryti išilginiai gręžimo profiliai. Pateikiamos tyrimo išvados ir rekomendacijos dėl inžinerinių tinklų įrengimo horizontalaus valdomo gręžimo metodu. / The paper analyzes the engineering networks in horizontal directional drilling method. Firstly there is the literature review, which discusses the factors that determine the excavation. Describe the open method of excavating the land, which is mainly used in the excavation. Discussed in trenchless technology, which are used as an alternative way of moving to an open ground in specific areas. The study methodology and the organization of the work submitted for drilling projects, and their analysis, the preparation stages of drilling, drilling machines and other equipment used in the study, characteristics. Considered boring machine selection methods described in the particular drilling and boring work. Research results presented in the analysis of drilling machines and the analysis of selected characteristics of the three drilling, directional drilling measurement protocols, and to set them up under the longitudinal drilling profiles. Presented the study findings and recommendations of the engineering networks in horizontal directional drilling method.
22

Ground displacements and pipe response during pulled-in-place pipe installation.

Cholewa, Johnathan 02 April 2009 (has links)
Polymer pipes, typically high density polyethylene (HDPE), can be pulled-into-place, avoiding traditional cut-and-cover construction, using pipe bursting and horizontal directional drilling (HDD) pipe installation techniques. Of particular interest, are the ground displacements, induced by cavity expansion, associated with these techniques and the strains that develop in existing pipes in response to these displacements. Further, the axial stress-strain response of the new HDPE pipe during and after the cyclic pulling force history required to pull the pipe into place is of interest. Surface displacements and strains in an adjacent polyvinyl chloride (PVC) pipe induced by static pipe bursting were measured during the replacement of a new unreinforced concrete pipe. For the pipe bursting geometry tested, the maximum vertical surface displacement measured at the ground surface was 6 mm, while the distribution of vertical surface displacements extended no more than 2 m on either side of the centreline. The maximum longitudinal strain measured in the PVC pipe was less than 0.1% and its vertical diameter decreased by only 0.5%, suggesting that pipe bursting did not jeopardize the long-term performance of the water pipe tested. In addition, results from identical stress relaxation and creep tests performed on whole pipe samples and coupons trimmed from a pipe wall were compared, and these demonstrated that the coupons exhibited higher modulus than the pipe samples. Therefore, isolated pipe samples, as opposed to coupons, were tested to quantify the stress-strain response of HDPE pipe during the simulated installation, strain recovery, and axial restraint stages of HDD. Axial strains were found to progressively accumulate when an HDPE pipe sample was subjected to the cyclic stress history used to simulate an HDD installation. It was shown that existing linear and nonlinear viscoelastic models can serve as predictive design tools for estimating the cyclic strain history of HDPE pipe during installation. For the specific conditions examined, the tensile axial stresses redeveloped in the pipe samples, once restrained, were not large enough to lead to long-term stress conditions conducive to slow crack growth even when the short-term performance limits were exceeded by a factor of 1.5. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2009-04-01 18:19:24.434
23

Proposta de um Roadmap para avaliação de riscos em projetos De perfuração direcional horizontal

Gomes, Mário Batista, Gomes, Mário Batista 31 August 2016 (has links)
Submitted by Leonardo Cavalcante (leo.ocavalcante@gmail.com) on 2018-06-04T11:08:08Z No. of bitstreams: 1 Arquivototal.pdf: 4740766 bytes, checksum: d645cbc9287ef5f4bd7672bcbfdaa031 (MD5) / Made available in DSpace on 2018-06-04T11:08:08Z (GMT). No. of bitstreams: 1 Arquivototal.pdf: 4740766 bytes, checksum: d645cbc9287ef5f4bd7672bcbfdaa031 (MD5) Previous issue date: 2016-08-31 / The relevance of the analysis and risk management in horizontal directional drilling projects are sedimented in the work developed based on tacit knowledge capture experts and builders of experience in order to model this knowledge from conceptual premises, a mathematical model capable to replicate efficiently the conceptual frameworks of the opinion of experts. Historical data of the failure modes that appear in HDD (Horizontal Directional Drilling) projects, allow us to add a simple set of qualitative techniques to manage and anticipate the occurrence of damage that result in financial, economic and social losses, security, productivity or quality. These techniques are easy to implement and eliminate the need for skilled labor to validate the results. The failures of historical data in prior projects, can provide the basic elements for modeling knowledge through a learning tool. For quantitative effect, the tool used was the Fuzzy Inference System (FIS). The variables that indicate the failure modes are taken from the existing knowledge database in the literature and applied to a set of 40 projects. The application of qualitative tools represented a significant reduction of accidents in the research organization. The SIF model (fuzzy inference system) proposed is able to predict based on expert opinion the risk of a project building on 05 key variables. The result of the inference of the quantitative model involves the quantification of the overall risk of a given project, on a scale of 1 to 10. The proposed interface simplifies quantification operation, providing agile the overall risk of the interest of project building on the conceptual indication 05 this risk input variables. The calculated risk be inferred about the risks associated with the project, facilitating the decisionmaking process of managers and builders. / A relevância da análise e gerenciamento de riscos em projetos de perfuração direcional horizontal está sedimentada nos trabalhos desenvolvidos com base na captação de conhecimento tácito de especialistas e na experiência de construtores com o objetivo de modelar esse conhecimento, proveniente de premissas conceituais, num modelo matemático capaz de replicar com eficiência as estruturas conceituais da opinião de experts. Os dados históricos dos modos de falha que se apresentam nos projetos HDD (Perfuração horizontal direcional) permitem agregar um conjunto simples de técnicas qualitativas, para gerenciar e antecipar a ocorrência de danos que impliquem em perdas financeiras, econômicas, sociais, de segurança, produtividade ou qualidade. Essas técnicas são de fácil implementação e dispensam a necessidade de mão de obra especializada para validação dos resultados. Os dados históricos de falhas ocorridas em projetos anteriores podem fornecer os elementos básicos para a modelagem do conhecimento através de uma ferramenta de aprendizagem. Para efeito quantitativo, a ferramenta utilizada neste trabalho foi o Sistema de Inferência Fuzzy (SIF). As variáveis que indicam os modos de falha foram extraídas da base de dados de conhecimento existente na literatura e aplicada sobre um conjunto de 40 projetos. A aplicação das ferramentas qualitativas representou uma redução significativa de acidentes na organização pesquisada. O modelo SIF (sistema de inferência fuzzy) proposto é capaz de prever com base na opinião especializada os riscos de um determinado projeto tomando por base 05 variáveis principais. O resultado da inferência do modelo quantitativo implica na quantificação do risco global de determinado projeto, numa escala de 1 a 10. A interface proposta simplifica a operação de quantificação, fornecendo de forma ágil o risco global do projeto de interesse tomando por base a indicação conceitual do risco presente em 05 variáveis de entrada. O risco calculado permite inferir sobre os riscos associados ao projeto, facilitando o processo decisório de gestores e construtores.
24

Analysis of Parameters Affecting Costs of Horizontal Directional Drilling Projects in the United States for Municipal Infrastructure

January 2010 (has links)
abstract: Horizontal Directional Drilling (HDD) is a growing and expanding trenchless method utilized to install pipelines from 2 to 60 inch diameters for lengths over 10,000 foot. To date, there are not many public documents where direct costs and bid prices incurred by HDD installations are available and analyzed. The objective is to provide a better understanding of the factors affecting the bid prices of these projects. The first section of the thesis analyzes how project parameters such as product diameter, bore length and soil conditions affect the bid price of water and wastewater pipeline installations using HDD. Through multiple linear regressions, the effect of project parameters on bid prices of small, medium and large rigs projects is extracted. The results were further investigated to gain a better understanding of bid factors that influence the relationship between total cost and the project parameters. The second section uses unit cost, based on bid prices, to compare the costs incurred by defined categories. Parameters such as community type, product type, soil conditions, and geographical region were used in the analysis. Furthermore, using average unit cost from 2001 to 2009, HDD project cost trends are briefly analyzed against the main variations of the US economy from the same time horizon by using economic indicators. It was determined that project geometric factors influence more the bid price of small rig projects than large rig projects because external factors including market rates and economic situation have an increasing impact on bid prices when rig size increases. It was observed that bid price variation of HDD projects over years followed the same trend as the US economic variation described by economic indicators. / Dissertation/Thesis / M.S. Construction 2010
25

Avaliação da precisão da declividade da técnica de perfuração direcional horizontal para instalações de redes de esgoto / Evaluation of the gradient precision of the horizontal directional drilling technique for the installation of gravity sewers

Fernando Galvanin Jamal 26 June 2008 (has links)
O presente trabalho está focado no método de perfuração direcional horizontal (HDD) para instalação de redes de esgoto gravitacional. Descrevem-se os resultados de diferentes técnicas com o objetivo de se atingir a exigência de declividade. Para tanto foram executados 4 furos experimentais simulando trechos daquelas redes, com extensão de 30 m e tubulação de PEAD com diâmetro externo de 125 mm. Estas instalações foram executadas na cidade de São Carlos, Brasil, em um solo classificado granulometricamente como uma areia argilosa. Para cada uma das 4 instalações, adotou-se um processo construtivo diferenciado. Esta diferenciação se deu a partir do diâmetro do alargador adotado, do número de passadas do mesmo e da execução de furos verticais para alívio de pressão no espaço anelar assim como medidas diretas de profundidade do furo piloto. Após a instalação dos dutos foram realizadas medidas altimétricas no interior dos mesmos possibilitando avaliar quantitativamente os resultados obtidos. Estes resultados indicam que ainda é necessário refinar a técnica de perfuração direcional para a execução das redes de esgoto. Entretanto é possível observar que as variações empregadas na execução de cada um dos furos conduzem a um caminho de melhoria nos resultados obtidos. Esta melhoria pode ser observada nos furos onde o alargador adotado apresentava menor diâmetro conduzindo a menores desvios na posição final do duto. Salientam-se também os benéficos resultados da execução dos furos verticais que conduziram a menores pressões no espaço anelar assim como possibilitaram medidas altimétricas diretas da posição do furo piloto. Desta forma, é provável que com um maior número de experimentos e incrementos tecnológicos se atinja o objetivo final, ou seja, executar redes de esgoto gravitacional com declividade constante e baixa. Em paralelo nas instalações executadas foram realizados testes para avaliação da precisão e acurácia do sistema de navegação responsável pelo fornecimento de informações de posição e temperatura da ferramenta de corte durante a execução do furo piloto. Este trabalho contempla ainda, a elaboração de uma nova solução para as instalações de esgoto executadas através do HDD. Esta solução propõe a aplicação de um esforço de tração a um elemento externo, uma geogrelha que envolve a tubulação, visando posicionar a mesma em declividade constante. Face a seu caráter inovador foram desenvolvidos equipamentos e procedimentos de ensaio de laboratório, para avaliar a aplicabilidade da solução na prática / The present work is focused on the horizontal directional drilling (HDD) method to install gravity sewers. The results of different techniques are described intending to meet the demands of gradient. Therefore, 4 experimental pilot bores were drilled simulating a section of those structures extending 30 m with HDPE pipelines of 125 mm external diameter. Those installations were engineered in the city of São Carlos, Brazil, in a clayey sand. For each of the 4 installations a distinct constructive process was adopted. Such characteristic was on account of the diameter of the selected reamer, the number of reamer steps and the vertical drills performed to relieve the pressure in the annular space, as well as the direct depth measurements of the pilot hole. After installing the pipes, altimetric measurements were performed inside them, hence enabling to quantitatively assess the obtained results. These results indicate the need to further refine the directional drilling technique for sanitary sewers. Yet it can be seen that the employed variations for each of the holes lead to an improved course of action with the observed results. Such improvement is perceived in the holes where the selected reamer had a smaller diameter, hence allowing for less displacement in the pipes final position. Also emphasized are the resulting benefits of the vertical drills that lead to less pressure in the annular space, as well as enabling altimetric measurements of the pilot hole position. Thus, it is presumed that with further experiments and technological developments the final objective is reached, meaning, putting into effect constant and low level gradient sewer networks. Tests for precision and accuracy assessment of the tracking system were also performed in each tube installed. The tracking system is responsible for providing information related to position and temperature of the drill head during the drilling operation. The steps for the development of a new HDD solution for sewer installation are presented. The idea is based on the application of a tensile force to an element external to the product, aiming at attaining a constant gradient. Equipments and procedures developed for this new technique are described.
26

Schaktfri ledningsbyggnad : En kostnadsanalys mellan styrd borrning och konventionell schaktning / Trenchless pipeline installation : A cost analysis between directional drilling and traditional excavation

Andersson, Sophia, Jonsén, Oscar January 2019 (has links)
Styrd borrning är en schaktfri metod för att förlägga ledningar i mark. Examensarbetet har utförts i samarbete med Styrud Ingenjörsfirma AB som uppfattat en okunskap i branschen över prisbilden för styrd borrning. Syftet med arbetet är att utföra en kostnadsanalys för att beskriva hur styrd borrning står sig ekonomiskt mot konventionell schaktning. Arbetet undersöker även vilka faktorer som påverkar en eventuell ekonomisk brytpunkt, vilken i detta arbete definieras som den punkt när en viss metod blir det ekonomiskt gynnsamma alternativet. Studien har utformats för att så objektivt som möjligt belysa ämnet med utgångspunkten att göra metoderna jämförbara analytiskt. För att genomföra en analys har en beräkningsmodell skapats. Målet med modellen och dess utformning är att den enkelt skall gå att bygga vidare på och utvecklas i framtiden samt att användas av projektörer som en fingervisning tidigt i projekteringsstadiet. Från beräkningsmodellen har 70 fiktiva fall studerats. Resultatet visar att styrd borrning är billigare i 73% av fallen. I övriga fall tyder resultatet på att styrd borrning som metod generellt sett inte är så dyrt att övervägning att använda metoden försvinner. Genom resultat och analys dras slutsatsen att styrd borrning i de flesta fall står sig ekonomiskt starkt som alternativ till konventionell schaktning. / Horizontal directional drilling is a trenchless method used to install pipelines underground. This thesis is conducted in collaboration with Styrud Ingenjörsfirma AB, who perceived lacking knowledge within the industry regarding the financial aspects of directional drilling. The purpose of this thesis is to carry out a cost analysis that defines how directional drilling stands financially against traditional excavation. The study also intends to describe which factors that influence a possible economic breakpoint, in this study referring to when a certain method becomes the economically strongest alternative. This thesis has been carried out to as objectively as possible describe the topic focusing on making the methods analytically comparable. To carry out the analysis, an economic model has been created. The model and its design have been created in a manner that makes it easy to develop it in the future and aims to act as a guide for project planners to indicate which method to proceed with. From the economic model, 70 cases have been studied. The result shows that directional drilling is cheaper in 73% of the cases. In the rest of the cases, the result suggests that directional drilling as a method generally is not so expensive that consideration of using the method disappears. Through results and analysis, it is concluded that directional drilling in most cases is a strong alternative to traditional excavation from an economic standpoint.
27

Zásady pro provádění řížených protlaků pod komunikacemi / Principles for the implementation of controlled pressures under roads

Komoň, Richard Unknown Date (has links)
Goal of the diploma thesis is to explain what does the term of controlled horizontal drilling mean and where it can be performed. Furthermore, it wants to show what to pay attention to during designing as well as during the actual pilot drill. Additionally, to show that pilot drill cannot be performed based on the project in all scenarios. Theoretical part of the thesis explains how the technology works and which auxiliaries are necessary to successfully perform controlled pressure. This technology is explained step by step in the practical part of the thesis to show how to proceed during the realization of controlled pressure.
28

Analyse et validation du comportement directionnel des outils de forage couplés aux systèmes de forage dirigé / Analysis and validation of drill bits directional behavior coupled with rotary steerable systems

Ben Hamida, Malek 13 June 2013 (has links)
Nous présentons dans ce mémoire un modèle d'interaction outil-roche qui calcule les efforts de forage en fonction du déplacement dans la roche d'un outil de forage de type PDC, et permet d'évaluer ses propriétés directionnelles, à savoir, son indice d'anisotropie (steerability) et son angle de walk. Le mouvement de l'outil est défini par une translation suivant trois axes et une rotation suivant deux axes. L'angle de tilt, qui définit l'inclinaison de l'outil par rapport à l'axe du trou en cours de forage, est pris en compte dans le calcul des surfaces d'interactions effectives entre les différentes composantes de l'outil (structure de coupe, garde active et garde passive) et la roche. Ce modèle outil est établi à partir d'une modélisation de la coupe de roche par un taillant. Ce modèle de coupe élémentaire est construit de manière à être applicable aux différentes parties de l'outil. Les efforts élémentaires de coupe sont intégrés sur toute la structure de l'outil de forage afin de calculer ses propriétés directionnelles. Le modèle d'interaction outil-roche est validé à partir d'essais de forage directionnel réalisés sur un banc spécialement conçu pour reproduire le comportement des systèmes de forage dirigé existants. Il constitue un outil d'aide à la décision pour la sélection de l'outil de forage en fonction du système au bout duquel il sera fixé. Ce modèle pourra aussi être intégré dans une boucle de régulation automatique ou semi-automatique de contrôle et de correction de la trajectoire en temps réel. / This work deals with the formulation of global relationships between kinematic variables describing the penetration of a PDC bit into the rock and drilling forces acting on it. This allows us determine the bit directional properties in terms of steerability, which corresponds to the bit lateral aggressiveness, and walk, which describes the bit azimuth displacement with respect to the side force. The bit kinematic quantities are divided into a three-axis penetration vector and a two-axis angular penetration vector. The bit tilt, which describes the angle between the bit revolution axis and the borehole tangent, is used to compute the effective interaction surface between the bit's different components (cutting structure, active gauge and passive gauge) and the rock. A new cutter-rock interface law is set up and experimentally validated in order to compute elementary forces acting on all parts of a drill bit. Bit directional properties are computed after the integration of these elementary forces. The bit-rock interaction model is experimentally validated with directional drilling tests held on a full-scale drilling bench developed to reproduce Rotary Steerable Systems (RSS) directional behavior. Tests and theoretical results enabled us to fully understand the roles of tilt angle, bit design, operating parameters and rock properties in the deviation process of a PDC bit. The bit-rock interaction model is a decision support tool for optimal drill bit selection according to the RSS being used. It could also be embedded in a real-time Closed-Loop Guided Directional Drilling controller in order to correct the drilling direction or follow a planned borehole trajectory.

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