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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.
1

A Comprehensive Decision Support System(CDSS) for Optimal Pipe Renewal using Trenchless Technologies

Khambhammettu, Prashanth 29 May 2002 (has links)
Water distribution system pipes span thousands of miles and form a significant part of the total infrastructure of the country. Rehabilitation of this underground infrastructure is one of the biggest challenges currently facing the water industry. Water main deterioration is twofold: the main itself loses strength over time and breaks; also, there is degradation of water quality and hydraulic capacity due to build of material within a main. The increasing repair and damage costs and degrading services demand that a deteriorating water main be replaced at an optimal time instead of continuing to repair it. In addition, expanding business districts, indirect costs, and interruptions including protected areas, waterways and roadways require examination of trenchless technologies for pipe installation. In this thesis a new threshold break rate criterion for the optimal replacement of pipes is provided. As opposed to the traditional present worth cost (PWC) criterion, the derived method uses the equivalent uniform annualized cost (EUAC). It is shown the EUAC based threshold break rate subsumes the PWC based threshold break rate. In addition, practicing engineers need a user-friendly decision support system to aid in the optimal pipeline replacement process. They also need a task-by-task cost evaluation in a project. As a part of this thesis a comprehensive decision support system that includes both technology selection knowledge base and cost evaluation spreadsheet program within a graphical user interface framework is developed. Numerical examples illustrating the theoretical derivations are also included. / Master of Science
2

Análise da utilização de métodos não-destrutivos como alternativa para redução dos custos sociais gerados pela instalação, manutenção e substituição de infra-estruturas urbanas subterrâneas / Analysis of the use of trenchless technology as an alternative to reduce social costs generated by installation, maintenance and substitution of buried urban infrastructure

Dezotti, Mateus Caetano 11 September 2008 (has links)
Comparativamente à abertura de valas, os métodos não-destrutivos de instalação, manutenção e substituição de infra-estruturas urbanas subterrâneas apresentam menor duração, necessitam de mínima ou nenhuma escavação na superfície e causam mínima interferência no tráfego, no comércio e em outras atividades locais. Avalia-se, neste trabalho, o potencial dos métodos não-destrutivos para reduzir, significativamente, os custos sociais e, conseqüentemente, o custo total pago pela sociedade, associado, por exemplo, à deterioração precoce dos pavimentos e a problemas ambientais. Os custos sociais, na maioria das vezes, são negligenciados ou até mesmo ignorados, sendo a escolha do método construtivo baseada apenas nos custos diretos. São fatores que contribuem para esse cenário a inexistência de um protocolo padrão para classificar e quantificar tais custos e o desconhecimento das tecnologias não-destrutivas por parte de engenheiros e profissionais responsáveis. Este trabalho apresenta, inicialmente, uma síntese dos principais componentes dos custos sociais e um breve resumo dos métodos não-destrutivos mais utilizados. Com um simulador de tráfego computacional foi realizada análise comparativa entre os métodos construtivos convencional (abertura de valas) e alternativo (não-destrutivo), quanto aos custos sociais referentes à interrupção do tráfego veicular e impactos ambientais. Os resultados mostraram que os custos sociais são consideravelmente menores com o emprego de métodos não-destrutivos, particularmente quanto aos custos com combustível e atrasos decorrente da interrupção ao tráfego veicular. / Compare to trench opening, the trenchless methods for installation, maintenance and substitution of buried urban infrastructure expend less time, need minimum or no excavation and cause minimum disruption of and interference to traffic, business and other local activities. In this work it is evaluated its potential to significantly reduce the social costs and consequently the total cost paid by the society, i.e., early pavement deterioration and environmental problems. The social costs, most of the time, are neglected or even ignored, being the selection of the construction method based on just on direct costs. This scenario is also due to the inexistence of a protocol to classify and quantify those costs and to the unknowing of trenchless technologies by engineers and other responsible professionals. This work presents, initially, a synthesis of the main components of social costs and a brief summary of the most used trenchless methods. With a computer traffic simulator it was performed a comparative analysis of conventional (trench opening) and alternative (trenchless) construction methods in terms of social costs associated to traffic disruption and environmental impacts. The results showed that social costs are much smaller when trenchless technologies are used, mainly due to the reduction of fuel costs and traffic delays.
3

Vamzdynų renovacija naudojant betranšėjes technologijas / Pipelines renovation using trenchless technologies

Tamulis, Mindaugas 03 June 2009 (has links)
Baigiamajame darbe pateikiama Jurbarko miesto, Vydūno gatvės vandentiekio ir nuotekų surinkimo tinklų vamzdynų būklės analizė. Tyrimų pradžioje vandentiekio ketinių vamzdžių linija (160 m ilgio) buvo diagnozuota televizinės įrangos GULLYVER pagalba. Nustatyta, kad vamzdyje yra išilginis trūkimas. Ištyrus esamas aplinkybes, priimtas sprendimas renovuoti vamzdyną betranšėjiniu būdu priverstinio įtraukimo metodu. Pasirinktas įrenginys Grundotrack „Mini – Gigant“. Nustatyta, kad norint atstatyti nusidėvėjusį vandentiekio vamzdyną, būtina įtraukti naują PE slėginį vandentiekio vamzdį 200 mm skersmens. Grundotrack „Mini – Gigant“ įrenginiu sulaužius senus ketinius vamzdžius, PE vamzdžiai įtraukti be kliūčių. Suskaičiavus darbų sąmatas nustatyta, kad naujo vamzdžio įtraukimas priverstiniu būdu, naudojant betranšėjas technologijas, kainavo 89168 Lt. Tokio pat vamzdžio paklojimas atviru būdu (iškasant tranšėjas) būtų kainavę 108008 Lt. Nuotakyno sistema (380 m ilgio) iš keramikinių 300 mm skersmens vamzdžių pirmiausia buvo diagnozuojama telekamera TELEMEC 100. Nustatyta, kad vamzdynas labai blogos būklės (išilginiai, skersiniai trūkimai, vamzdžio sandurų prasikeitimai ir trūkimai) ir reikalinga skubi vamzdyno renovacija. Ištyrus esamas aplinkybes, priimtas sprendimas renovuoti vamzdyną betranšėjiniu būdu, taikant rankovės metodą. / The final paper analyses the condition of the water supply and sewerage collection network pipelines of Vydūno street, Jurbarkas. First of all, the line of the cast iron pipes (160 meter long) of the water supply system were diagnosed by the use of the television equipment GULLYVER. Longitudinal split in the pipe was discovered. Upon examination of the existing circumstances, the decision was made to renovate the pipeline by trenchless mode, by applying forced pulling method. The device Grundotrack Muni – Gigant was selected for completion of this task. It was established that in order to restore the worn water supply pipeline, a new PE pressure water supply pipe of 200 mm diameter needs to be installed. After the old cast iron pipes were broken by the device Grundotrack Mini - Gigant, the PE pipes were installed without any problems. Having calculated the work estimates, it was established that installation of the new pipe by forced method, through application of trenchless technologies, cost LTL 89168. Open laying (by excavating trenches) of the same pipe would have cost LTL 108008. The sewerage system (380 meter long) consisting of 300 mm diameter ceramic pipes was initially diagnosed by camera TELEMEC 100. Very poor condition of the pipeline was determined (longitudinal, cross fractures, changes and fractures of the pipe joints) and need for urgent renovation of the pipeline was established. Upon examination of the existing circumstances, the decision was made to... [to full text]
4

Comparative Analysis of Horizontal Directional Drilling Construction Methods in China

January 2014 (has links)
abstract: As a developing nation, China is currently faced with the challenge of providing safe, reliable and adequate energy resources to the county's growing urban areas as well as to its expanding rural populations. To meet this demand, the country has initiated massive construction projects to expand its national energy infrastructure, particularly in the form of natural gas pipeline. The most notable of these projects is the ongoing West-East Gas Pipeline Project. This project is currently in its third phase, which will supply clean and efficient natural gas to nearly sixty million users located in the densely populated Yangtze River Delta. Trenchless Technologies, in particular the construction method of Horizontal Directional Drilling (HDD), have played a critical role in executing this project by providing economical, practical and environmentally responsible ways to install buried pipeline systems. HDD has proven to be the most popular method selected to overcome challenges along the path of the pipeline, which include mountainous terrain, extensive farmland and numerous bodies of water. The Yangtze River, among other large-scale water bodies, have proven to be the most difficult obstacle for the pipeline installation as it widens and changes course numerous times along its path to the East China Sea. The purpose of this study is to examine those practices being used in China in order to compare those to those long used practices in the North American in order to understand the advantages of Chinese advancements. Developing countries would benefit from the Chinese advancements for large-scale HDD installation. In developed areas, such as North America, studying Chinese execution may allow for new ideas to help to improve long established methods. These factors combined further solidify China's role as the global leader in trenchless technology methods and provide the opportunity for Chinese HDD contractors to contribute to the world's knowledge for best practices of the Horizontal Directional Drilling method. / Dissertation/Thesis / Doctoral Dissertation Civil Engineering 2014
5

Análise da utilização de métodos não-destrutivos como alternativa para redução dos custos sociais gerados pela instalação, manutenção e substituição de infra-estruturas urbanas subterrâneas / Analysis of the use of trenchless technology as an alternative to reduce social costs generated by installation, maintenance and substitution of buried urban infrastructure

Mateus Caetano Dezotti 11 September 2008 (has links)
Comparativamente à abertura de valas, os métodos não-destrutivos de instalação, manutenção e substituição de infra-estruturas urbanas subterrâneas apresentam menor duração, necessitam de mínima ou nenhuma escavação na superfície e causam mínima interferência no tráfego, no comércio e em outras atividades locais. Avalia-se, neste trabalho, o potencial dos métodos não-destrutivos para reduzir, significativamente, os custos sociais e, conseqüentemente, o custo total pago pela sociedade, associado, por exemplo, à deterioração precoce dos pavimentos e a problemas ambientais. Os custos sociais, na maioria das vezes, são negligenciados ou até mesmo ignorados, sendo a escolha do método construtivo baseada apenas nos custos diretos. São fatores que contribuem para esse cenário a inexistência de um protocolo padrão para classificar e quantificar tais custos e o desconhecimento das tecnologias não-destrutivas por parte de engenheiros e profissionais responsáveis. Este trabalho apresenta, inicialmente, uma síntese dos principais componentes dos custos sociais e um breve resumo dos métodos não-destrutivos mais utilizados. Com um simulador de tráfego computacional foi realizada análise comparativa entre os métodos construtivos convencional (abertura de valas) e alternativo (não-destrutivo), quanto aos custos sociais referentes à interrupção do tráfego veicular e impactos ambientais. Os resultados mostraram que os custos sociais são consideravelmente menores com o emprego de métodos não-destrutivos, particularmente quanto aos custos com combustível e atrasos decorrente da interrupção ao tráfego veicular. / Compare to trench opening, the trenchless methods for installation, maintenance and substitution of buried urban infrastructure expend less time, need minimum or no excavation and cause minimum disruption of and interference to traffic, business and other local activities. In this work it is evaluated its potential to significantly reduce the social costs and consequently the total cost paid by the society, i.e., early pavement deterioration and environmental problems. The social costs, most of the time, are neglected or even ignored, being the selection of the construction method based on just on direct costs. This scenario is also due to the inexistence of a protocol to classify and quantify those costs and to the unknowing of trenchless technologies by engineers and other responsible professionals. This work presents, initially, a synthesis of the main components of social costs and a brief summary of the most used trenchless methods. With a computer traffic simulator it was performed a comparative analysis of conventional (trench opening) and alternative (trenchless) construction methods in terms of social costs associated to traffic disruption and environmental impacts. The results showed that social costs are much smaller when trenchless technologies are used, mainly due to the reduction of fuel costs and traffic delays.
6

Statické řešení vodovodního potrubí při bezvýkopové technologii / Static Solution of Water Pipes in Trenchless Technology

Mráčková, Martina January 2013 (has links)
The paper provides an overview of the most widely used trenchless technologies and the possibility of their utilization for laying new thermoplastic pipelines. It analyzes the static behavior of thermoplastic water pipes placed into the existing steel pipes using relining technology. The program system ANSYS is used as a tool for static solution of pipelines. Obtained results are compared with conventional approaches.
7

Исследование эффективности инновационных технологий капитального ремонта трубопроводов водоснабжения на этапах жизненного цикла : магистерская диссертация / Study of the effectiveness of innovative technologies for the overhaul of water supply pipelines at the stages of the life cycle

Реш, В. А., Resh, V. A. January 2022 (has links)
Разработана экономическая модель формирования инвестиций в попериодный горизонт до 15,30,50 лет и требуемой ставке дохода с применением функции «формирования фонда возмещения» определены равномерные периодические платежи, необходимые для получения итогового объема инвестиций в будущем. / An economic model has been developed for the formation of investments in a period horizon of up to 15,30,50 years and the required rate of return using the function of "formation of the compensation fund" determined uniform periodic payments necessary to obtain the final volume of investments in the future.
8

Podchod vodovodu pod dálničním tělesem s využitím mikrotunelu / The aqueduct under the highway through of the microtunnel

Hoza, Martin January 2017 (has links)
During the construction of water pipeline Strelice is necessary to overcome the D1 motorway. This thesis deals with design of the motorway crossing using trenchless technologies. Combination of pipejacking and shield tunneling is chosen. Static calculation includes determination of the jacking force, proposal of the thrust block and assessment of the reinforced concrete jacking pipes.
9

Návrh sanace vybrané části stokové sítě ve městě Valašské Meziříčí / Design of rehabilitation of selected parts of the sewer network in Valašské Meziříčí

Škařupová, Karolína January 2014 (has links)
The aim of this master´s thesis was design of rehabilitation of selected parts of the sewer network in Valašské Meziříčí. The work is divided into several parts. The first part is a description of the preliminary research based on appointments with the operator of the sewer network. The second section describes the basic information on the assessment of the sewer network. In the third part, the evaluation of technical and operational conditions according to ČSN EN 13 508. This section was supplemented by creation of supportive software program in Microsoft Office Excel, which is based on the proposed TNV 756905. In the next part the environmental assessment was performed digging and trenchless technology and then selected a possibility representative to design of selected parts. The fifth and sixth section contains technical and economic evaluation designed technology. A final section deals with the choosing optimal rehabilitation technologies for the design of selected parts of the sewer network.

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