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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 Pavement Maintenance and Rehabilitation Project Formation and Prioritization Methodology that Reflects Agency Priorities and Improves Network Condition

Narciso, Paul John Ross 16 December 2013 (has links)
Methodical maintenance and renewal of infrastructure systems is critical due to the rapid deterioration of infrastructure assets under increasing loads and environmental effects and the scarcity of resources allocated for their preservation. A crucial step in pavement management is the formation and prioritization of maintenance and rehabilitation (M&R) projects that compete for limited funding for inclusion in the agency’s multiyear pavement management plan (PMPs). In general, many highway agencies perform this task subjectively, and thus a more rational and objective approach is desired to produce sound and justifiable PMPs. Specifically, such methodology should take into account the multiple factors that are considered by engineers in prioritizing M&R projects. This research addresses this need by developing a methodology for use by the Texas Department of Transportation (TxDOT) in preparing their four-year PMPs. Several key decision factors were considered and TxDOT decision makers were surveyed to weigh these factors as to their influence on prioritizing M&R projects. These were then used to develop a priority score for each candidate M&R project. Since TxDOT collects and stores data for individual 0.5-mile pavement sections, these sections must be grouped in a logical scheme to form realistic candidate M&R projects. The incremental benefit-cost analysis was performed on the candidate M&R projects to identify a set of M&R projects that maximizes network’s priority score under budgetary constraint. Future pavement condition was projected using performance prediction models and the process is repeated throughout the planning horizon to produce a multi-year pavement management plan. Data from Bryan district, which consists of 7,075 lane-miles of roadway, were used to develop and validate the PMP methodology. Comparison with the actual PMP (produced by TxDOT) shows some disagreements with the PMP generated by the methodology though the latter was shown to produce more cost-effective and defendable pavement management plans. Since the methodology is founded on TxDOT engineers’ decision criteria and preferences, they can be assured that the PMPs produced by this methodology are in line with their goals and priorities.
2

A Two-Phase Maintenance and Rehabilitation Framework for Pavement Assets under Performance Based Contracts

Alyami, Zaid January 2012 (has links)
Traditional Canadian pavement construction contracts provide detailed specifications for the work that needs to be carried out. This is the case for both maintenance and rehabilitation contracts. However, for many road agencies around the world, this traditional way of contracting had shortcomings. These agencies have been proactive in changing their contracts to maintain the road networks while reducing the cost. The challenge of maintaining the road networks to the highest possible condition while investing the minimal amount of money has promoted innovative contracting approaches. Furthermore, road agencies have increased the private sector involvement through warranty contracts. According to road agencies around the world, there has been a movement over the last two decades towards Performance Based Contracts (PBCs); a long term warranty contract. In PBCs, the client agency specifies certain clearly defined minimal performance measures to be met or exceeded during the contract period and payments are explicitly linked to the contractor successfully meeting or exceeding those performance measures. Therefore, the PBC maintenance and rehabilitation selection differs significantly from that of traditional asset management contracts and more complex due to the pavement deterioration process and probability of failure to achieve the specified level of service for various performance measures along the contract period. This thesis involves the development of a novel framework that facilitates the selection of maintenance and rehabilitation activities for pavement assets under PBCs. The framework consists of two phases. Phase-One, called the Initial Program, uses historical data, performance modeling, and optimization to establish and select the maintenance and rehabilitation program for the bidding stage. Phase-Two, called Project Asset Management, is implemented after the contract is awarded. This phase uses the contract performance monitoring data and the cost estimate from Phase-One as a baseline budget to update and validate the established program through performance modeling and optimization. A case study using data from the Ministry of Transportation Ontario (MTO) second generation Pavement Management System (PMS2) is used to illustrate the framework.
3

A Two-Phase Maintenance and Rehabilitation Framework for Pavement Assets under Performance Based Contracts

Alyami, Zaid January 2012 (has links)
Traditional Canadian pavement construction contracts provide detailed specifications for the work that needs to be carried out. This is the case for both maintenance and rehabilitation contracts. However, for many road agencies around the world, this traditional way of contracting had shortcomings. These agencies have been proactive in changing their contracts to maintain the road networks while reducing the cost. The challenge of maintaining the road networks to the highest possible condition while investing the minimal amount of money has promoted innovative contracting approaches. Furthermore, road agencies have increased the private sector involvement through warranty contracts. According to road agencies around the world, there has been a movement over the last two decades towards Performance Based Contracts (PBCs); a long term warranty contract. In PBCs, the client agency specifies certain clearly defined minimal performance measures to be met or exceeded during the contract period and payments are explicitly linked to the contractor successfully meeting or exceeding those performance measures. Therefore, the PBC maintenance and rehabilitation selection differs significantly from that of traditional asset management contracts and more complex due to the pavement deterioration process and probability of failure to achieve the specified level of service for various performance measures along the contract period. This thesis involves the development of a novel framework that facilitates the selection of maintenance and rehabilitation activities for pavement assets under PBCs. The framework consists of two phases. Phase-One, called the Initial Program, uses historical data, performance modeling, and optimization to establish and select the maintenance and rehabilitation program for the bidding stage. Phase-Two, called Project Asset Management, is implemented after the contract is awarded. This phase uses the contract performance monitoring data and the cost estimate from Phase-One as a baseline budget to update and validate the established program through performance modeling and optimization. A case study using data from the Ministry of Transportation Ontario (MTO) second generation Pavement Management System (PMS2) is used to illustrate the framework.
4

Considerações sobre os custos de pavimentos rígidos com base em conceitos de gerência de pavimentos / not available

Severi, Andréa Arantes 28 November 1997 (has links)
Este trabalho apresenta considerações sobre os custos de pavimentos rígidos, abordando os custos de construção, os custos de manutenção e reabilitação e os custos de operação dos veículos. Apresenta, inicialmente, uma revisão dos fatores intervenientes no dimensionamento de pavimentos rígidos, particularmente os métodos adotados pela Associação Brasileira de Cimento Portland (ABCP) e pela American Association of State Highways and Transportation Officials (AASHTO), e os procedimentos construtivos mais utilizados no Brasil. As atividades de manutenção e reabilitação são associadas às principais formas de deterioração dos pavimentos rígidos, tomando-se como referência, neste trabalho, o Manual de Identificação de Defeitos do Programa SHRP. Quanto aos custos que incidem sobre os usuários e que dependem, principalmente, da condição da superfície de rolamento, são analisadas a influência da curva de desempenho e a estimativa elos custos ele operação dos veículos a partir ela irregularidade longitudinal dos pavimentos. Desenvolve-se uma programação fatorial de simulações que tem como fatores o método ele dimensionamento, o módulo de reação do subleito e o volume de tráfego. Analisam-se, ao final, a importância relativa desses fatores sobre cada urna das parcelas que compõem o custo total de um pavimento rígido. / This work analyses the costs of rigid pavements, that are compound by construction, maintenance and rehabilitation, and user costs. It is presented the basic concepts of rigid pavement design, mainiy the Brazilian Association of Portland Cement (ABCP) and the American Association of State Highways and Transportation Officials (AASHTO) methods, and the construction procedures most used in Brazil. The maintenance and rehabilitation activities are related to rigid pavement distresses, and in this work the reference is the Distress Identification Manual developed by the SHRP Program. In terms of user costs, which are due to pavement rolling condition, it is analyzed the importance of performance trends and the estimation of user costs from pavement roughness. It is developed a factorial simulation program considering the following factors: rigid pavement design method, modulus of subgrade reaction, and traffic volume. It is analyzed the relative effects of each factor on the rigid pavements total cost.
5

Considerações sobre os custos de pavimentos rígidos com base em conceitos de gerência de pavimentos / not available

Andréa Arantes Severi 28 November 1997 (has links)
Este trabalho apresenta considerações sobre os custos de pavimentos rígidos, abordando os custos de construção, os custos de manutenção e reabilitação e os custos de operação dos veículos. Apresenta, inicialmente, uma revisão dos fatores intervenientes no dimensionamento de pavimentos rígidos, particularmente os métodos adotados pela Associação Brasileira de Cimento Portland (ABCP) e pela American Association of State Highways and Transportation Officials (AASHTO), e os procedimentos construtivos mais utilizados no Brasil. As atividades de manutenção e reabilitação são associadas às principais formas de deterioração dos pavimentos rígidos, tomando-se como referência, neste trabalho, o Manual de Identificação de Defeitos do Programa SHRP. Quanto aos custos que incidem sobre os usuários e que dependem, principalmente, da condição da superfície de rolamento, são analisadas a influência da curva de desempenho e a estimativa elos custos ele operação dos veículos a partir ela irregularidade longitudinal dos pavimentos. Desenvolve-se uma programação fatorial de simulações que tem como fatores o método ele dimensionamento, o módulo de reação do subleito e o volume de tráfego. Analisam-se, ao final, a importância relativa desses fatores sobre cada urna das parcelas que compõem o custo total de um pavimento rígido. / This work analyses the costs of rigid pavements, that are compound by construction, maintenance and rehabilitation, and user costs. It is presented the basic concepts of rigid pavement design, mainiy the Brazilian Association of Portland Cement (ABCP) and the American Association of State Highways and Transportation Officials (AASHTO) methods, and the construction procedures most used in Brazil. The maintenance and rehabilitation activities are related to rigid pavement distresses, and in this work the reference is the Distress Identification Manual developed by the SHRP Program. In terms of user costs, which are due to pavement rolling condition, it is analyzed the importance of performance trends and the estimation of user costs from pavement roughness. It is developed a factorial simulation program considering the following factors: rigid pavement design method, modulus of subgrade reaction, and traffic volume. It is analyzed the relative effects of each factor on the rigid pavements total cost.
6

Development and Implementation of a Network-Level Pavement Optimization Model

Wang, Shuo January 2011 (has links)
No description available.
7

Co-Location Decision Tree for Enhancing Decision-Making of Pavement Maintenance and Rehabilitation

Zhou, Guoqing 02 March 2011 (has links)
A pavement management system (PMS) is a valuable tool and one of the critical elements of the highway transportation infrastructure. Since a vast amount of pavement data is frequently and continuously being collected, updated, and exchanged due to rapidly deteriorating road conditions, increased traffic loads, and shrinking funds, resulting in the rapid accumulation of a large pavement database, knowledge-based expert systems (KBESs) have therefore been developed to solve various transportation problems. This dissertation presents the development of theory and algorithm for a new decision tree induction method, called co-location-based decision tree (CL-DT.) This method will enhance the decision-making abilities of pavement maintenance personnel and their rehabilitation strategies. This idea stems from shortcomings in traditional decision tree induction algorithms, when applied in the pavement treatment strategies. The proposed algorithm utilizes the co-location (co-occurrence) characteristics of spatial attribute data in the pavement database. With the proposed algorithm, one distinct event occurrence can associate with two or multiple attribute values that occur simultaneously in spatial and temporal domains. This research dissertation describes the details of the proposed CL-DT algorithms and steps of realizing the proposed algorithm. First, the dissertation research describes the detailed colocation mining algorithm, including spatial attribute data selection in pavement databases, the determination of candidate co-locations, the determination of table instances of candidate colocations, pruning the non-prevalent co-locations, and induction of co-location rules. In this step, a hybrid constraint, i.e., spatial geometric distance constraint condition and a distinct event-type constraint condition, is developed. The spatial geometric distance constraint condition is a neighborhood relationship-based spatial joins of table instances for many prevalent co-locations with one prevalent co-location; and the distance event-type constraint condition is a Euclidean distance between a set of attributes and its corresponding clusters center of attributes. The dissertation research also developed the spatial feature pruning method using the multi-resolution pruning criterion. The cross-correlation criterion of spatial features is used to remove the nonprevalent co-locations from the candidate prevalent co-location set under a given threshold. The dissertation research focused on the development of the co-location decision tree (CL-DT) algorithm, which includes the non-spatial attribute data selection in the pavement management database, co-location algorithm modeling, node merging criteria, and co-location decision tree induction. In this step, co-location mining rules are used to guide the decision tree generation and induce decision rules. For each step, this dissertation gives detailed flowcharts, such as flowchart of co-location decision tree induction, co-location/co-occurrence decision tree algorithm, algorithm of colocation/co-occurrence decision tree (CL-DT), and outline of steps of SFS (Sequential Feature Selection) algorithm. Finally, this research used a pavement database covering four counties, which are provided by NCDOT (North Carolina Department of Transportation), to verify and test the proposed method. The comparison analyses of different rehabilitation treatments proposed by NCDOT, by the traditional DT induction algorithm and by the proposed new method are conducted. Findings and conclusions include: (1) traditional DT technology can make a consistent decision for road maintenance and rehabilitation strategy under the same road conditions, i.e., less interference from human factors; (2) the traditional DT technology can increase the speed of decision-making because the technology automatically generates a decision-tree and rules if the expert knowledge is given, which saves time and expenses for PMS; (3) integration of the DT and GIS can provide the PMS with the capabilities of graphically displaying treatment decisions, visualizing the attribute and non-attribute data, and linking data and information to the geographical coordinates. However, the traditional DT induction methods are not as quite intelligent as one's expectations. Thus, post-processing and refinement is necessary. Moreover, traditional DT induction methods for pavement M&R strategies only used the non-spatial attribute data. It has been demonstrated from this dissertation research that the spatial data is very useful for the improvement of decision-making processes for pavement treatment strategies. In addition, the decision trees are based on the knowledge acquired from pavement management engineers for strategy selection. Thus, different decision-trees can be built if the requirement changes. / Ph. D.
8

Desenvolvimento de um programa de sistema de gerência de pavimentos urbanos para cidades brasileiras de médio porte / Development of an urban pavements management system program for Brazilian medium-sized cities

Shoji, Eunice Satie 24 March 2000 (has links)
Este trabalho apresenta um sistema de gerência de pavimentos urbanos desenvolvido especialmente para cidades brasileiras de médio porte. Representa uma ferramenta que auxilia o processo de tomada de decisões em relação à alocação racional dos recursos financeiros disponíveis, visando a maior extensão possível de pavimentos seguros, confortáveis e, principalmente, econômicos aos usuários. Um sistema especialista simplificado foi desenvolvido com a finalidade de selecionar as estratégias de manutenção e reabilitação em função da condição do pavimento, sua idade e seu volume de tráfego. Em caso das necessidades serem superiores aos recursos disponíveis, um processo de priorização das seções é aplicado. Com o objetivo de validar o programa computacional (SGPUSP/R), foi desenvolvido um projeto piloto composto por 13 seções da malha viária urbana do município de São Carlos-SP, onde um planejamento financeiro e orçamentário durante um período de análise de 4 anos foi realizado. / This work presents an urban pavements management system developed particularly for Brazilian medium-sized cities. It represents a tool to aid the decision making process related to rational allocation of the available budget, providing the maximum extension of safe, comfortable and, mainly, low cost pavements to the users. A simplified expert system was developed aiming the selection of maintenance and rehabilitation strategies in function of pavement condition, age, and diary traffic volume. When the estimated needs are higher than the available budget, a prioritization process is applied to select the sections for maintenance and rehabilitation strategies. For the validation of the computer program (SGPUSP/R), a pilot study composed by 13 sections in the São Carlos City network was developed, and a budget planning during an analysis period of 4 years was performed.
9

Desenvolvimento de um programa de sistema de gerência de pavimentos urbanos para cidades brasileiras de médio porte / Development of an urban pavements management system program for Brazilian medium-sized cities

Eunice Satie Shoji 24 March 2000 (has links)
Este trabalho apresenta um sistema de gerência de pavimentos urbanos desenvolvido especialmente para cidades brasileiras de médio porte. Representa uma ferramenta que auxilia o processo de tomada de decisões em relação à alocação racional dos recursos financeiros disponíveis, visando a maior extensão possível de pavimentos seguros, confortáveis e, principalmente, econômicos aos usuários. Um sistema especialista simplificado foi desenvolvido com a finalidade de selecionar as estratégias de manutenção e reabilitação em função da condição do pavimento, sua idade e seu volume de tráfego. Em caso das necessidades serem superiores aos recursos disponíveis, um processo de priorização das seções é aplicado. Com o objetivo de validar o programa computacional (SGPUSP/R), foi desenvolvido um projeto piloto composto por 13 seções da malha viária urbana do município de São Carlos-SP, onde um planejamento financeiro e orçamentário durante um período de análise de 4 anos foi realizado. / This work presents an urban pavements management system developed particularly for Brazilian medium-sized cities. It represents a tool to aid the decision making process related to rational allocation of the available budget, providing the maximum extension of safe, comfortable and, mainly, low cost pavements to the users. A simplified expert system was developed aiming the selection of maintenance and rehabilitation strategies in function of pavement condition, age, and diary traffic volume. When the estimated needs are higher than the available budget, a prioritization process is applied to select the sections for maintenance and rehabilitation strategies. For the validation of the computer program (SGPUSP/R), a pilot study composed by 13 sections in the São Carlos City network was developed, and a budget planning during an analysis period of 4 years was performed.
10

Uso dos Sistemas de Informação Geográfica para a integração da gerência de pavimentos urbanos com as atividades das concessionárias de serviços públicos / not available

Gómez Pantigoso, José Francisco 27 April 1998 (has links)
Neste trabalho são analisados os Sistemas de Gerência de Pavimentos Urbanos (SGPU) e os Sistemas de lnformação Geográfica (SIG) visando a obtenção de formas com que possam ser aplicados para a compatibilização das atividades de gerência de todas as redes de infra-estrutura pública urbana (pavimento, água, esgoto, telefone, gás, energia elétrica). Desenvolve-se um projeto piloto, utilizando o aplicativo de SIG TransCAD para a gerência de pavimentos sob duas condições: na primeira, através de uma interface com um programa de gerência de pavimentos urbanos já em utilização (URMS, desenvolvido na Universidade do Texas em Austin); na segunda, como plataforma para o desenvolvimento de um novo sistema de gerência de pavimentos, tanto em nível de rede como em nível de projeto. São utilizadas bases de dados para o pavimento e para a rede de água de abastecimento, criadas para a análise de viabilidade da compatibilização da gerência de pavimentos com as atividades de concessionárias de serviços públicos urbanos, a qual confirmou a grande potencialidade do uso dos Sistemas de Informação Geográfica para a gerência integrada e racional da infra-estrutura pública urbana. / This work presents studies about Urban Pavement Management Systems (U-PMS) and Geographic lnformation Systems (GIS) aiming their utilization as a tool for the harmonization of urban infrastructure (pavement, gas, electric power, sewer, water, telephone) maintenance and rehabilitation activities. lt is developed a pilot study using the SIG software called TransCAD for pavement management under two conditions: the first one, through an interface with an already in use pavement management system (URMS, developed at the University of Texas at Austin); the second one, as a framework for the development of a new pavement management system, at network and project levels. Data bases for pavement and water networks are used for analysis of the harmonization of pavement management with other public infrastructure activities, which confirmed the great power of GIS for utilization in a rational and integrated urban infrastructure management system.

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