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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

Real Time Data Acquisition and Prediction Model Comparison using Maxi Directional Drills

Verwey, Kyle January 2013 (has links)
Horizontal Directional Drilling (HDD) is used around the world when traditional open cut methods are not practical or impossible for installing pipelines. Maxi-sized drill rigs are the largest and most powerful directional drills and are more common in the field than ever before with over 5,000 rigs in operation world wide. The complexity of installations and the design associated with them continues to increase. This research has two main objectives. 1. Develop a real time data acquisition system for monitoring pullback forces on the product pipe; and, 2. Compare data gathered using maxi-sized drill rigs with current modelling methods using BoreAid. The first portion of the research, as listed above, required attaching multiple pressure transducers to the drilling display panel in an American Auger DD-1100 drill rig and recording, in real time, the carriage, rotation, and mud pressure as seen by the operator. This research also describes the various challenges and issues associated with developing real time in-the-bore data acquisition processes. Finally, future recommendations for further development of the in-the-bore data acquisition are discussed. The second portion of this research describes how the gathered data was processed into a workable data set. The field data was then compared to theoretical models by using the drill assistant tool BoreAid. The results of this comparison show that these models are appropriate for all size drill rigs, although some limitations are present.
2

Real Time Data Acquisition and Prediction Model Comparison using Maxi Directional Drills

Verwey, Kyle January 2013 (has links)
Horizontal Directional Drilling (HDD) is used around the world when traditional open cut methods are not practical or impossible for installing pipelines. Maxi-sized drill rigs are the largest and most powerful directional drills and are more common in the field than ever before with over 5,000 rigs in operation world wide. The complexity of installations and the design associated with them continues to increase. This research has two main objectives. 1. Develop a real time data acquisition system for monitoring pullback forces on the product pipe; and, 2. Compare data gathered using maxi-sized drill rigs with current modelling methods using BoreAid. The first portion of the research, as listed above, required attaching multiple pressure transducers to the drilling display panel in an American Auger DD-1100 drill rig and recording, in real time, the carriage, rotation, and mud pressure as seen by the operator. This research also describes the various challenges and issues associated with developing real time in-the-bore data acquisition processes. Finally, future recommendations for further development of the in-the-bore data acquisition are discussed. The second portion of this research describes how the gathered data was processed into a workable data set. The field data was then compared to theoretical models by using the drill assistant tool BoreAid. The results of this comparison show that these models are appropriate for all size drill rigs, although some limitations are present.
3

Time dependent response of pulled-in-place HDPE pipes

Chehab, Abdul Ghafar 19 June 2008 (has links)
Horizontal directional drilling is increasingly used to install pipes without costs and disruptions associated with conventional ‘cut and cover’ installations. This technique, which was developed by industrial innovators, feature complex soil and pipe response which is not well understood. The success of this operation depends on knowledge of the pulling forces applied, level of ground disturbance, ground expansion or fracture from mud pressure, and the effect of the pulling operation on the pipes. Tensile stresses in the pipe vary with time during and after installation, and along the pipe. This applies especially to polymer pipes where the stresses during insertion and those over the service life of the pipe may influence its performance. The main objective of this study is to model the short term and long term response of pipes installed using horizontal directional drilling and to investigate the effect of the time dependent behaviour of polymer pipes, as well as other installation variables on the performance of the pipe during and after installation. The mechanical behaviour of high density polyethylene used to manufacture a significant portion of pipes installed using horizontal directional drilling is investigated and two sophisticated constitutive models are developed to simulate the time-dependent behaviour of high density polyethylene. The interaction between the pipe and the surrounding soil during horizontal directional drilling installations is also investigated and modelled. A FORTRAN algorithm is developed to calculate the short and long term response of elastic and polymeric pipes installed using horizontal directional drilling. The program uses the HDPE constitutive models as well as the pipe-soil interaction model developed in the study. After evaluation, the developed program is employed in a parametric study on the sensitivity of short term and long term pipe response to different parameters, including the effect of overstressing the pipe during installation. As Multiaxial modeling is necessary for accurate analysis of some applications including the swagelining method, a uniaxial constitutive model developed in the current study is generalized to a multi-axial model that can simulate the response to biaxial stress-strain fields. The multi-axial model is implemented in a finite element code and its performance in simulating multiaxial stress-strain fields is evaluated. / Thesis (Ph.D, Civil Engineering) -- Queen's University, 2008-06-12 18:03:43.501
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

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

Jamal, Fernando Galvanin 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.
6

Pavement Deterioration and PE Pipe Behaviour Resulting from Open-Cut and HDD Pipeline Installation Techniques

Adedapo, Adedamola Adedeji 14 September 2007 (has links)
The damaging impact of continuous utility cuts on flexible pavement performance has been shown to be a major problem for urban roads and pavement mangers due to high reconstruction and maintenance costs. Horizontal Directional Drilling (HDD) is a trenchless construction method that does not require continuous trenching. HDD pipe installation techniques can reduce reinstatement costs, shorten construction periods, and lower social costs due to reduced user traffic delays. In this thesis, a detailed field study and numerical investigations was completed to quantify pavement deterioration and polyethylene (PE) pipe performance when pipelines are installed under flexible pavements using both traditional open-cut and HDD construction methods. Two 200mm SDR-17 DIPS HDPE pipes were installed 1.5m below a flexible pavement using open-cut and HDD construction technique. A state-of-the-art instrumentation and data acquisition systems were developed to measure HDD drill rig, PE pipes and pavement responses during pipe installations and for a period of about three years afterwards. Field data from (GPR) surveys, falling weight deflectometer (FWD) tests, surface distress surveys, and ground surface elevation survey were used to evaluate pavement deterioration due to the pipeline installations. The mechanisms of ground deformations during HDD and open-cut pipe installation were numerically investigated with FLAC3D, a commercial finite difference program. A hybrid constitutive model consisting of the traditional Duncan-Chang hyperbolic model and Mohr-Coulomb perfectly plastic model was developed and implemented in FLAC3D to simulate the non-linear stress-strain and stress dependent behavior of granular materials. Field test results show that the HDD installed pipe have significantly lower construction induced strains and ring deflections when compared to the open cut-and-cover installation and the mechanism of pipe deformation differs for the two construction techniques. The two pipes performed satisfactory over the long-term monitoring period as deflections and strain levels were below acceptable limits and there was no apparent deterioration of the pipe. Pipe deflections resulting from environmental effects (freeze and thaw) were found to be more significant than those due to material creep. Furthermore, the modified Iowa’s and Plastic Pipe Institute’s (PPI) ring deflection equations were found to over estimate pipe deflection for the open-cut and HDD installed pipes by about 114 and 50 percent, respectively. Results from field tests found that the HDD installation did not results in any observable change in the condition of the pavement structure performance, while the structure and integrity of pavement section in the vicinity of the open-cut was adversely impacted by utility cut excavation. It was determined numerically that when an unsupported excavation is created within a typical flexible pavement structure, distress zones that extend laterally from the face of the excavation to a distance of approximately 80% of the depth of excavation is developed. The results of the analyses suggests that better restoration techniques are required to eliminate the adverse effect caused by the stress relief within the pavement structure during a utility cut. Furthermore, the area of potential pavement deterioration should be extended beyond the edge of the utility cut to encompass the ‘distress zones’ when determining fees to cover pavement damage and restoration costs. Results obtained from numerical simulations advanced the understanding of the mechanism, magnitude, and extent of deformation within the pavement structure during HDD pipe installation in frictional and cohesive subgrade soils. Relationship between HDD annular bore pressures and displacements have been incorporated into design Charts and Tables for use in estimating maximum allowable bore pressures for HDD installation beneath flexible pavements. Critical bore pressures that would limit ground deformations and prevent excessive pavement deformations are presented. Critical bore pressures were compared to estimated allowable bore pressures obtained from the widely used Delft Geotechnics equation. The Delft Geotechnics equation was found to over estimate allowable bore pressure for HDD installation beneath flexible pavement. HDD pipeline installations under flexible pavement were found to have significantly lower restoration costs, social costs and maintenance cost than open-cut pipeline installations.
7

Pavement Deterioration and PE Pipe Behaviour Resulting from Open-Cut and HDD Pipeline Installation Techniques

Adedapo, Adedamola Adedeji 14 September 2007 (has links)
The damaging impact of continuous utility cuts on flexible pavement performance has been shown to be a major problem for urban roads and pavement mangers due to high reconstruction and maintenance costs. Horizontal Directional Drilling (HDD) is a trenchless construction method that does not require continuous trenching. HDD pipe installation techniques can reduce reinstatement costs, shorten construction periods, and lower social costs due to reduced user traffic delays. In this thesis, a detailed field study and numerical investigations was completed to quantify pavement deterioration and polyethylene (PE) pipe performance when pipelines are installed under flexible pavements using both traditional open-cut and HDD construction methods. Two 200mm SDR-17 DIPS HDPE pipes were installed 1.5m below a flexible pavement using open-cut and HDD construction technique. A state-of-the-art instrumentation and data acquisition systems were developed to measure HDD drill rig, PE pipes and pavement responses during pipe installations and for a period of about three years afterwards. Field data from (GPR) surveys, falling weight deflectometer (FWD) tests, surface distress surveys, and ground surface elevation survey were used to evaluate pavement deterioration due to the pipeline installations. The mechanisms of ground deformations during HDD and open-cut pipe installation were numerically investigated with FLAC3D, a commercial finite difference program. A hybrid constitutive model consisting of the traditional Duncan-Chang hyperbolic model and Mohr-Coulomb perfectly plastic model was developed and implemented in FLAC3D to simulate the non-linear stress-strain and stress dependent behavior of granular materials. Field test results show that the HDD installed pipe have significantly lower construction induced strains and ring deflections when compared to the open cut-and-cover installation and the mechanism of pipe deformation differs for the two construction techniques. The two pipes performed satisfactory over the long-term monitoring period as deflections and strain levels were below acceptable limits and there was no apparent deterioration of the pipe. Pipe deflections resulting from environmental effects (freeze and thaw) were found to be more significant than those due to material creep. Furthermore, the modified Iowa’s and Plastic Pipe Institute’s (PPI) ring deflection equations were found to over estimate pipe deflection for the open-cut and HDD installed pipes by about 114 and 50 percent, respectively. Results from field tests found that the HDD installation did not results in any observable change in the condition of the pavement structure performance, while the structure and integrity of pavement section in the vicinity of the open-cut was adversely impacted by utility cut excavation. It was determined numerically that when an unsupported excavation is created within a typical flexible pavement structure, distress zones that extend laterally from the face of the excavation to a distance of approximately 80% of the depth of excavation is developed. The results of the analyses suggests that better restoration techniques are required to eliminate the adverse effect caused by the stress relief within the pavement structure during a utility cut. Furthermore, the area of potential pavement deterioration should be extended beyond the edge of the utility cut to encompass the ‘distress zones’ when determining fees to cover pavement damage and restoration costs. Results obtained from numerical simulations advanced the understanding of the mechanism, magnitude, and extent of deformation within the pavement structure during HDD pipe installation in frictional and cohesive subgrade soils. Relationship between HDD annular bore pressures and displacements have been incorporated into design Charts and Tables for use in estimating maximum allowable bore pressures for HDD installation beneath flexible pavements. Critical bore pressures that would limit ground deformations and prevent excessive pavement deformations are presented. Critical bore pressures were compared to estimated allowable bore pressures obtained from the widely used Delft Geotechnics equation. The Delft Geotechnics equation was found to over estimate allowable bore pressure for HDD installation beneath flexible pavement. HDD pipeline installations under flexible pavement were found to have significantly lower restoration costs, social costs and maintenance cost than open-cut pipeline installations.
8

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.
9

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.
10

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

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