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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

Development of a Sustainable Management System for Rural Road Networks in Developing Countries

Chamorro Gine, Marcela Alondra 06 November 2014 (has links)
Rural roads play a crucial role in the economic and social development of societies, linking rural communities to education, health services and markets. During the last decade, considerable efforts have been made to evaluate the benefits of rural road investment in developing countries. Although outputs of these studies have led to a global rethinking of traditional road appraisal methods, limited attempts have been made to integrate these findings to the rural road management process. For the sustainable management of rural roads, social, institutional, technical, economic and environmental aspects should be considered under a long term perspective. The current practice in developing countries is that only some of these key sustainable aspects are being considered in the management process. In addition, rural roads maintenance management is commonly performed under a short term basis, not considering the life cycle costs and benefits in the economic analysis and project prioritization. Available management tools and studies have essentially focused their efforts on improving technical and economic aspects of low-volume roads. Whereas, the common practice observed in face of limited resources and lack of technical skills is that decisions are made under a political short term perspective. This research is directed at the development of an applied and practical system for the sustainable management of rural road networks in developing countries. The approach considers the development of all components required by the proposed management system and their integration into a practical and easy-to-use computer tool. To achieve this goal a sustainable framework for rural roads management was first developed, where system components and modules were defined. A network level condition evaluation methodology was selected and validated. Long term condition performance models were calibrated from the probabilistic analysis of field data. Optimal maintenance standards were developed under a cost-effectiveness approach. A long term prioritization procedure was developed to account for sustainable aspects of rural roads in the management process. A computer tool was finally developed to integrate the system components and display them in a friendly interface for potential users. The tool was programed in Visual Basic, considering Microsoft Excel interface. The computer tool considers the four system components: Input Data, System Modules, Network Analysis Interface and Output Data. System Modules include Condition Performance Module, Network Maintenance Module and Long Term Prioritization Module. For each of the system components and modules a separate worksheet has been included in the computer tool. The tool is centered on the Network Analysis Interface, which interacts with the other three system components. The user enters network data in the Input Data interface and may adjust information in System Modules considered if the network under study has differences to predefined conditions of. Adjustments to System Modules can be performed by the user, however it is advised that prior calibration is required for the successful analysis of the network. The management system was applied and validated in two rural road networks in developing countries located in Chile and Paraguay. Sensitivity analysis was carried out to assess the impacts of input parameters in the performance of developed system. As a result of the research an adaptable and adoptable sustainable management system for rural networks was developed to assist local road agencies in developing countries.
2

The development of a conceptual framework for a district 4-Year Pavement Management Plan

Hwang, Jea Won 30 September 2011 (has links)
The Texas Department of Transportation (TxDOT) is concerned about the widening gap between preservation needs and available funding. Funding levels are not adequate to meet the preservation needs of the roadway network; therefore projects listed in the 4-Year Pavement Management Plan must be ranked to determine which projects should be funded now and which can be postponed until a later year. Currently, each district uses locally developed methods to rank and prioritize projects. These ranking methods have relied on less formal qualitative assessments based on engineers’ subjective judgment. It is important for TxDOT to have a rational 4-Year Pavement Management Plan. The objective of this study is to develop a conceptual framework that describes the development of the 4-Year Pavement Management Plan and a proposed ranking process. It can be largely divided into three steps; (1) Network-Level preliminary project screening process, (2) Project-Level project ranking process, and (3) Economic Analysis. A rational pavement management procedure and a project ranking method that are accepted by districts and the TxDOT administration will maximize efficiency in budget allocations and help improve pavement condition. As a part of this study, based on the data provided by the Austin District Pavement Engineer, the Network-Level Project Screening (NLPS) tool, including the candidate project selection algorithm and the preliminary project screening matrix, is developed. The NLSP tool has been used by the Austin District Pavement Engineer (DPE) to evaluate the PMIS (Pavement Management Information System) data and to prepare a preliminary list of candidate projects for further evaluation. The automated tool will help TxDOT engineers easily incorporate the developed mathematical algorithm into their daily pavement maintenance management. / text
3

Federal Road Management for Sub-Saharan African Nations: A Nigerian Case Study

Campbell, Alex January 2009 (has links)
The World Bank specifically indicates that poor transport infrastructure and services in sub-Saharan Africa are serious obstacles to poverty reduction (Plessis-Fraissard, 2007). Two thirds of Africa's rural population, who are some 300 million of the world's poorest people, do not have access to an all-weather road. The same holds true for the federal paved network, further compounding the issues of health and economy. In the case of Nigeria, the majority of their federal network was constructed decades ago and little, if any, pavement management has been conducted. Further, federal roads that have been reconstructed or new roads that have been built are done so with inferior materials, inadequate designs and lack of quality control during the building process. Contributing to the poor state of the federal road network are high traffic volumes and traffic loads, as heavily overloaded trucks are commonplace. Nigeria has understood the need to improve their federal road network if they are to achieve the Millennium Development Goals they have outlined. As such, the Federal Roads Maintenance Agency (FERMA) was created and set in motion a mandate of federal road improvement through more appropriate design, construction, and above all else, pavement management. The major challenge, however, is that they are starting the process without a database, pavement management system, or an appreciation of the condition of their federal road network. The primary objective of this thesis is to form the foundation of a pavement management system (PMS) that FERMA can immediately implement to make better decisions pertaining to rehabilitation options. Further, it is the intent to allow for appropriate decisions about the best type of maintenance and rehabilitation interventions to apply to the poor state of arterial roads taking into context various factors, least of which are the type and extent of distress present and the benefit cost analysis. The outcome of this thesis will assist sub-Saharan Africa, but principally Nigeria, in their goal of fostering economic growth and creating a more sustainable transportation network. Recommendations on how to simplify input factors necessary for Nigeria to initiate a database and prepare more regionally specific designs have been made, including traffic, climatic and subgrade classifications. Economic analysis included present worth of costs (PWC) that were derived from condition rating curves specific to intervention pavement life and performance. Based on preliminary findings, subject to field validation, a chip-seal specific rehabilitation strategy for low volume federal roads is more cost effective over the 20-year analysis period, and 1-lift of asphalt concrete (AC) is more cost effective over the 20-year analysis period for high volume federal roads. Recommendations for further research have been made.
4

Federal Road Management for Sub-Saharan African Nations: A Nigerian Case Study

Campbell, Alex January 2009 (has links)
The World Bank specifically indicates that poor transport infrastructure and services in sub-Saharan Africa are serious obstacles to poverty reduction (Plessis-Fraissard, 2007). Two thirds of Africa's rural population, who are some 300 million of the world's poorest people, do not have access to an all-weather road. The same holds true for the federal paved network, further compounding the issues of health and economy. In the case of Nigeria, the majority of their federal network was constructed decades ago and little, if any, pavement management has been conducted. Further, federal roads that have been reconstructed or new roads that have been built are done so with inferior materials, inadequate designs and lack of quality control during the building process. Contributing to the poor state of the federal road network are high traffic volumes and traffic loads, as heavily overloaded trucks are commonplace. Nigeria has understood the need to improve their federal road network if they are to achieve the Millennium Development Goals they have outlined. As such, the Federal Roads Maintenance Agency (FERMA) was created and set in motion a mandate of federal road improvement through more appropriate design, construction, and above all else, pavement management. The major challenge, however, is that they are starting the process without a database, pavement management system, or an appreciation of the condition of their federal road network. The primary objective of this thesis is to form the foundation of a pavement management system (PMS) that FERMA can immediately implement to make better decisions pertaining to rehabilitation options. Further, it is the intent to allow for appropriate decisions about the best type of maintenance and rehabilitation interventions to apply to the poor state of arterial roads taking into context various factors, least of which are the type and extent of distress present and the benefit cost analysis. The outcome of this thesis will assist sub-Saharan Africa, but principally Nigeria, in their goal of fostering economic growth and creating a more sustainable transportation network. Recommendations on how to simplify input factors necessary for Nigeria to initiate a database and prepare more regionally specific designs have been made, including traffic, climatic and subgrade classifications. Economic analysis included present worth of costs (PWC) that were derived from condition rating curves specific to intervention pavement life and performance. Based on preliminary findings, subject to field validation, a chip-seal specific rehabilitation strategy for low volume federal roads is more cost effective over the 20-year analysis period, and 1-lift of asphalt concrete (AC) is more cost effective over the 20-year analysis period for high volume federal roads. Recommendations for further research have been made.
5

The Effects of Dynamic Decision Making on Resource Allocation: The Case of Pavement Management

Friedman, Sheldon 02 May 2003 (has links)
Pavement performance is a broad term that tries to describe how changing usage and varying conditions effect changes in pavement conditions. Measures of performance such as the Pavement Serviceability Index (PSI), the Pavement Condition Index (PCI) or Pavement Quality Index are available for use. Modeling pavement management is an essential activity of a pavement management system. Currently, models are used in the pavement planning and budget development process, as well as in helping to determine pavement life cycle management (George, Rajagopal, and Lim 1989). This process provides a means to plan for both routine maintenance and full rehabilitation of current roads. Maintaining these roads in good order is essential to providing a safe and rapid means of ground transportation in order to support both the current and future economic needs of our communities. System Dynamics is a simulation modeling process that was developed by Jay Forrester while at MIT. The modeling process allows the modeler to capture both the structure of the system under study and the decision rules used by members of the system that affect the behavior of the system. The modeling process is based on the concept that real world systems are non-linear in nature and the results of actions taken feedback and effect the system necessitating new actions. The objective of this study will be to use the System Dynamics modeling process to: Determine if and how current pavement management practices contribute to problems that pavement managers deal with on a day to day basis. Develop a set of recommendations to improve those practices that are found to contribute to or create the problem. Provide a tool that pavement managers can use to test their own proposed changes to their management practices in the form of a simulated environment.
6

The Effects of Dynamic Decision Making on Resource Allocation: The Case of Pavement Management

Friedman, Sheldon 02 May 2003 (has links)
Pavement performance is a broad term that tries to describe how changing usage and varying conditions effect changes in pavement conditions. Measures of performance such as the Pavement Serviceability Index (PSI), the Pavement Condition Index (PCI) or Pavement Quality Index are available for use. Modeling pavement management is an essential activity of a pavement management system. Currently, models are used in the pavement planning and budget development process, as well as in helping to determine pavement life cycle management (George, Rajagopal, and Lim 1989). This process provides a means to plan for both routine maintenance and full rehabilitation of current roads. Maintaining these roads in good order is essential to providing a safe and rapid means of ground transportation in order to support both the current and future economic needs of our communities. System Dynamics is a simulation modeling process that was developed by Jay Forrester while at MIT. The modeling process allows the modeler to capture both the structure of the system under study and the decision rules used by members of the system that affect the behavior of the system. The modeling process is based on the concept that real world systems are non-linear in nature and the results of actions taken feedback and effect the system necessitating new actions. The objective of this study will be to use the System Dynamics modeling process to: Determine if and how current pavement management practices contribute to problems that pavement managers deal with on a day to day basis. Develop a set of recommendations to improve those practices that are found to contribute to or create the problem. Provide a tool that pavement managers can use to test their own proposed changes to their management practices in the form of a simulated environment.
7

Development of appropriate technology road condition monitoring system

Beitelmal, Jamal A. January 1999 (has links)
This dissertation is concerned with the principles of pavement management systems and their applications in western and developing countries. The first part of the dissertation deals with the principles of pavement engineering and the role of the different layers in order to gain the required knowledge in highway pavement components, which will allow a cost-effective repair related to each specific defect. The second part deals with the existing systems for monitoring pavement condition and evaluatest heir benefit in assessingh ighway condition. The study shows the main problems usually militate against using the sophisticated technology in monitoring highway condition and implementing maintenance management systems in some cities in developing countries. In addition to the problems inherent in cities in developing countries, the city of Benghazi in Libya has special factors which have developed as a result of UN sanctions which were imposed in 1992. Therefore, the city of Benghazi has been selected as a case study for this particular research since it is a typical example of most cities in developing countries in terms of size, population and in ten-ns of lack of maintenance resources and skilled labour (Benghazi might have been so well resourcedth at it would no longer fall into the categoryo f developingc ity but for the sanction). The objectives of the study are attained through conclusions which indicate that establishing a pavement maintenance strategy in the city of Benghazi based on any or some of the sophisticated technology in road condition monitoring is not appropriate. This conclusion is tested by manufacturing a unique prototype measuring machine and using it in pilot monitoring exercises in the cities of Newcastle and Sunderland. The results of these pilot exercises are analysed to evaluate the benefit which such appropriate technology equipment can bring to the issue of monitoring of pavement condition in cities in developing countries having problems similar to those that prevail in Benghazi. The prototype equipment developed in this study is unique in that it is purely mechanical and uses no electronics in monitoring road condition. Moreover, all parts of the machine are fabricated from materials available in most cities in developing countries and therefore such machines could be easily maintained locally. The prototype described in this study is not only relevant to road monitoring but points the way towards the development of similar equipment in many engineering situations in developing countries. This research study points engineers in similar conditions in the direction that the Author thinks they should follow in applying their engineering abilities in developing countries.
8

Um Programa de Gerência de Pavimentos para o Comando da Aeronáutica - Estudo de caso : bases aéreas da região sul / A pavement management program for the brazilian air force - case study: air bases of the south region

Cordovil, Ricardo Miranda January 2010 (has links)
Esta dissertação trata do desenvolvimento de um protótipo de Sistema de Gerência de Pavimentos para a rede de aeroportos militares administrados pelo Comando da Aeronáutica (COMAER) e apresenta uma metodologia para a execução da Gerência de Pavimentos no âmbito do COMAER, a fim de subsidiar a elaboração do Plano Plurianual de Obras da Aeronáutica. Para tanto, foram levantadas as informações disponíveis, bem como o inventário de pavimentos das bases aéreas subordinadas ao Quinto Comando Aéreo Regional (V COMAR), o histórico de condição e de intervenção dos pavimentos dos últimos 5 anos, dados de projeto, custos e tráfego aéreo e, a partir desses elementos e de indicações do desempenho dos pavimentos estudados, foi elaborada uma proposta plurianual de investimentos em termos de obras de conservação, a fim de prolongar a vida útil dos mesmos, permitindo um aproveitamento mais racional dos recursos existentes. Além disso, para integrar as informações fragmentadas entre os diversos elos do Sistema de Engenharia espalhados pelo Brasil, foi desenvolvido um Sistema de banco de dados para possibilitar a consulta e cadastramento das avaliações através da INTRAER, a rede interna do Comando da Aeronáutica. / This dissertation concerns in the development of a prototype of a preliminary Pavement Management System for the network of military airports managed by the Brazilian Air Force (COMAER) and aims to provide a methodology for the implementation of the pavement management within the Brazilian Air Force, in order to support the development of the multi-year plan of works. To do it so, the existing information system and the inventory of airfields pavements subject to the Fifth Regional Air Command (COMAR V) was raised, the history of the condition and intervention of decks in the past five years, project data, costs, air traffic and from these elements and performance measures of the pavements studied was an elaborate multi-year investment proposal in terms of conservation works in order to extend the pavement life wich aim at a more rational utilization of resources. In addition, to integrate the fragmented information between the various links of Engineering System throughout Brazil, it was developed a database system to enable to consult and register evaluations through the INTRAER, the internal network of the Brazilian Air Force.
9

Um Programa de Gerência de Pavimentos para o Comando da Aeronáutica - Estudo de caso : bases aéreas da região sul / A pavement management program for the brazilian air force - case study: air bases of the south region

Cordovil, Ricardo Miranda January 2010 (has links)
Esta dissertação trata do desenvolvimento de um protótipo de Sistema de Gerência de Pavimentos para a rede de aeroportos militares administrados pelo Comando da Aeronáutica (COMAER) e apresenta uma metodologia para a execução da Gerência de Pavimentos no âmbito do COMAER, a fim de subsidiar a elaboração do Plano Plurianual de Obras da Aeronáutica. Para tanto, foram levantadas as informações disponíveis, bem como o inventário de pavimentos das bases aéreas subordinadas ao Quinto Comando Aéreo Regional (V COMAR), o histórico de condição e de intervenção dos pavimentos dos últimos 5 anos, dados de projeto, custos e tráfego aéreo e, a partir desses elementos e de indicações do desempenho dos pavimentos estudados, foi elaborada uma proposta plurianual de investimentos em termos de obras de conservação, a fim de prolongar a vida útil dos mesmos, permitindo um aproveitamento mais racional dos recursos existentes. Além disso, para integrar as informações fragmentadas entre os diversos elos do Sistema de Engenharia espalhados pelo Brasil, foi desenvolvido um Sistema de banco de dados para possibilitar a consulta e cadastramento das avaliações através da INTRAER, a rede interna do Comando da Aeronáutica. / This dissertation concerns in the development of a prototype of a preliminary Pavement Management System for the network of military airports managed by the Brazilian Air Force (COMAER) and aims to provide a methodology for the implementation of the pavement management within the Brazilian Air Force, in order to support the development of the multi-year plan of works. To do it so, the existing information system and the inventory of airfields pavements subject to the Fifth Regional Air Command (COMAR V) was raised, the history of the condition and intervention of decks in the past five years, project data, costs, air traffic and from these elements and performance measures of the pavements studied was an elaborate multi-year investment proposal in terms of conservation works in order to extend the pavement life wich aim at a more rational utilization of resources. In addition, to integrate the fragmented information between the various links of Engineering System throughout Brazil, it was developed a database system to enable to consult and register evaluations through the INTRAER, the internal network of the Brazilian Air Force.
10

Um Programa de Gerência de Pavimentos para o Comando da Aeronáutica - Estudo de caso : bases aéreas da região sul / A pavement management program for the brazilian air force - case study: air bases of the south region

Cordovil, Ricardo Miranda January 2010 (has links)
Esta dissertação trata do desenvolvimento de um protótipo de Sistema de Gerência de Pavimentos para a rede de aeroportos militares administrados pelo Comando da Aeronáutica (COMAER) e apresenta uma metodologia para a execução da Gerência de Pavimentos no âmbito do COMAER, a fim de subsidiar a elaboração do Plano Plurianual de Obras da Aeronáutica. Para tanto, foram levantadas as informações disponíveis, bem como o inventário de pavimentos das bases aéreas subordinadas ao Quinto Comando Aéreo Regional (V COMAR), o histórico de condição e de intervenção dos pavimentos dos últimos 5 anos, dados de projeto, custos e tráfego aéreo e, a partir desses elementos e de indicações do desempenho dos pavimentos estudados, foi elaborada uma proposta plurianual de investimentos em termos de obras de conservação, a fim de prolongar a vida útil dos mesmos, permitindo um aproveitamento mais racional dos recursos existentes. Além disso, para integrar as informações fragmentadas entre os diversos elos do Sistema de Engenharia espalhados pelo Brasil, foi desenvolvido um Sistema de banco de dados para possibilitar a consulta e cadastramento das avaliações através da INTRAER, a rede interna do Comando da Aeronáutica. / This dissertation concerns in the development of a prototype of a preliminary Pavement Management System for the network of military airports managed by the Brazilian Air Force (COMAER) and aims to provide a methodology for the implementation of the pavement management within the Brazilian Air Force, in order to support the development of the multi-year plan of works. To do it so, the existing information system and the inventory of airfields pavements subject to the Fifth Regional Air Command (COMAR V) was raised, the history of the condition and intervention of decks in the past five years, project data, costs, air traffic and from these elements and performance measures of the pavements studied was an elaborate multi-year investment proposal in terms of conservation works in order to extend the pavement life wich aim at a more rational utilization of resources. In addition, to integrate the fragmented information between the various links of Engineering System throughout Brazil, it was developed a database system to enable to consult and register evaluations through the INTRAER, the internal network of the Brazilian Air Force.

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