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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.
11

Utah Commercial Motor Vehicle Weigh-in-Motion Data Analysis and Calibration Methodology

Seegmiller, Luke W. 30 November 2006 (has links) (PDF)
In preparation for changes in pavement design methodologies and to begin to assess the effectiveness of the weigh-in-motion (WIM) system in Utah, the Utah Department of Transportation (UDOT) contracted with a Brigham Young University (BYU) research team to conduct an evaluation of their commercial motor vehicle (CMV) data collection system statewide. The objective of this research was to evaluate the CMV data collection program in the state of Utah and to make limited recommendations for potential improvements and changes that will aid in more detailed and accurate CMV data collection across the state. To accomplish the research objectives, several tasks were conducted, including: 1) a review of literature to establish the state-of-the-practice for CMV monitoring, 2) collection of WIM data for the state of Utah, 3) analysis of the collected WIM data, 4) development of a calibration methodology for use in the state, and 5) presentation of recommendations and conclusions based on the research. The analysis of collected WIM data indicated that the CMV data collection system in the state of Utah currently produces data consistent with expectations with a few exceptions. Recommendations for improvements to the CMV data collection system come in the form of a proposed calibration methodology that is in line with current standards and the practices in other states. The proposed calibration methodology includes calibration, verification, and a quality assurance programs.
12

Correlation Of Acoustic Emission Parameters With Weight And Velocity Of Moving Vehicles

Kolgaonkar, Amar 01 January 2005 (has links)
The thesis is motivated by the goal of doing initial investigation and experimentation for the development of Weigh-in-Motion (WIM) system using acoustic emission phenomenon. A great deal of research is going on for measuring the weight of moving vehicles. Weigh-in-motion of commercial vehicles is essential for management of freight traffic, highway infrastructure design and maintenance, and monitoring of heavy weight vehicles. The research work presents a methodology for correlating the weight of a moving vehicle with acoustic emission parameters (such as counts and energy). Furthermore, the correlation between the speed of vehicle with the acoustic emission parameters is developed. Preliminary analysis and experimentations were conducted for the study of propagation of acoustic signals in plate like structure and effect of dynamic loadings on Kaiser Effect. Initial testing revealed that there is a linear correlation between the impact force and the acoustic emission parameters. Also a polynomial regression of second order was found between the speed of vehicle and acoustic emission parameters. Road testing was conducted to investigate the correlation between weight of the vehicle and acoustic emission parameters. A linear relation was found between the weight of vehicle and acoustic emission parameters represented by counts, signal energy and absolute energy.
13

Post-calibration and quality management of weigh-in-motion traffic data

De Wet, Dirk Pieter Gerhardus 03 1900 (has links)
Thesis (MScEng (Process Engineering))--University of Stellenbosch, 2010. / Thesis presented in fulfilment of the requirements for the degree of Master of Science in Engineering at Stellenbosch University / ENGLISH ABSTRACT: Weigh-in-motion (WIM) scales are installed on various higher order South African roads to provide traffic loading information for pavement design, strategic planning and law enforcement using a scientific approach. The two most respected international guideline documents for WIM systems are the American ASTM E1318 Standard and the COST 323 European Specification, yet neither are fully suited to be applied to local WIM systems. The author developed a post-calibration method for WIM data, called the Truck Tractor (TT) Method, to correct the magnitude of recorded axle loads in retrospect. It incorporates a series of powerful data quality checks. The TT Method is robust, accurate and adequately simple to be used on a routine basis. The TT Method uses the truck tractor loads of articulated 6- and 7-axle trucks with single steering- and double driving axles – these vehicle are called Eligible Trucks. Only Eligible Trucks with average axle loads between 6.5 t and 8.5 t are used in the calibration process – these vehicles are called Selected Trucks. A calibration factor, kTT, is determined using a fully automated iterative procedure, and multiplied with all axle load measurements to produce data for which the average truck tractor load of Selected Trucks, TTT, is equal to 21.8 t. The TT Method can be used for WIMs in various operating environments and is not sensitive to the extent of miss-calibration of a WIM, clipping of sensors owing to poor lane discipline or different extents of loading on different routes. The TT Method includes a series of data quality checks that can be used on a routine basis. They are summarised as follows: - The standard deviation of truck tractor loads for Selected Trucks, STTT, should always be below 2.0 t, but preferably below 1.9 t. - The standard deviation of front axle loads for Selected Trucks, SFTT, should always be below 0.9 t, but preferably below 0.8 t. - The post-calibration factor from the TT Method, kTT, should be between 0.9 and 1.1. The factor for any month should not deviate by more than 3% from the moving average of the previous five months. - The average of front axle loads of Selected Trucks, FTT, should be between 5.6 t and 6.6 t; the exact values are influenced by load transfer between the steering and driving axles. - A procedure was formulated using the Front axle / Truck tractor Ratio, FTR, to identify the percentage of Eligible Trucks that in all probability clipped the sensor. The percentage of these records must be below 10 %, but preferably below 6 %. The TT Method has the potential to significantly improve WIM data collection in South Africa. The calibration module of the TT Method, i.e. the procedure to calculate kTT, has already been accepted by SANRAL. Most of the data quality checking concepts associated with the TT Method were also accepted, although their threshold values are still being refined. / AFRIKAANSE OPSOMMING: Weeg-in-beweging (“weigh-in-motion”, WIM) skale word op talle hoë orde paaie in Suid- Afrika gebruik om op wetenskaplike wyse verkeersinligting te verskaf wat gebruik word vir plaveiselontwerp, strategiese beplanning en wetstoepassing met betrekking tot oorlading. Nie een van die twee vooraanstaande internasionale riglyne vir WIM sisteme, die ASTM E1318 Standaard en die COST 323 Europese Spesifikasie, is in geheel geskik vir Suid-Afrikaanse kondisies nie. Die outeur het ‘n unieke kalibrasie metode, genaamd die TT Metode, ontwikkel wat ’n reeks roetine kwaliteitsbeheertoetse vir WIM data insluit. Die TT Metode is eenvoudig, akkuraat en toepaslik vir ’n wye verskeidenheid WIM sisteme in Suid-Afrika. Die massa van trekkers van geartikuleerde 6- en 7-as vragmotors met enkel stuur- en dubbel dryf-aste en ’n gemiddelde asmassa tussen 6.5 en 8.5 ton (ook genoem Geselekteerde Vragmotors) word as verwysingsmassa gebruik. ’n Iteratiewe prosedure word gevolg vir die bepaling van die kalibrasie faktor, kTT. Dieselfde faktor word met alle asmassas in die data vir die analise periode vermenigvuldig, met die einddoel dat die gemiddelde trekker massa van die Geselekteerde Vragmotors, TTT, gedryf word na die teikenwaarde van 21.8 ton. Die TT Metode is ewe toepaslik ongeag die tipiese belading van trokke op ’n roete, hoe goed die WIM sisteem oorspronklik gekalibreer was of hoe goed laandissipline by die WIM sensor is. Die kwaliteitsbeheertoetse kan op ’n roetine basis toegepas word as deel van die uitvoering van WIM kalibrasie prosedure, en word soos volg saamgevat: - Die standaard afwyking van trekker massas van Geselekteerde Vragmotors, STTT, behoort altyd laer as 2.0 ton, maar verkieslik laer as 1.9 ton te wees. - Die standaard afwyking van voor-as massas van Geselekteerde Trokke, SFTT, behoort altyd laer as 0.9 ton, maar vekieslik laer as 0.8 ton te wees. - Die kalibrasiefaktor, kTT, moet verkieslik tussen 0.9 en 1.1 wees, en mag nie met meer as 3 % van die gemiddelde kTT vir die voorafgaande vyf maande verskil nie. - Die gemiddeld van voor-as massas van Geselekteerde Vragmotors, FTT, behoort tussen 5.6 ton en 6.6 ton te wees. Die presiese waarde hang af van die mate waartoe gewig tussen die voor-as en dubbel dryf-as oorgedra word weens dinamiese effekte op die trekker. - Die verhouding tussen die voor-as en dubbel dryf-as, bekend as die FTR, kan gebruik word as ‘n aanduiding of ’n trok weens swak laandissipline slegs gedeeltelik oor die WIM sensor gery het. Die persentasie gedeeltelike metings moet laer as 10%, maar verkieslik laer as 6 % wees. Die TT Metode het die potensiaal om die insameling en kwaliteit van verkeersdata deur middel van WIM sisteme noemenswaarding te verbeter. Die kalibrasie module van die TT Metode, m.a.w. die prosedure om kTT te bereken, is reeds deur SANRAL aanvaar. Die meeste van die kwaliteitsbeheerkonsepte wat met die TT Metode gepaard gaan is ook aanvaar, maar die drempelwaardes hiervoor word nog verfyn.
14

Options for providing quality axle load data for pavement design

Wood, Steven 30 March 2017 (has links)
This research evaluates four options to produce quality axle load data for pavement design: piezoelectric WIM sites (corrected and uncorrected data), static weigh scales, and a piezo-quartz WIM site. The evaluation applies four data quality principles: data validity, spatial coverage, temporal coverage, and data availability. While all principles are considered, the research contributes in the development and application of an integrated and sequential approach to assess data validity of the options by performing analyses to determine the precision and accuracy of axle load measurements. Within the context of Manitoba, the evaluation reveals that data produced by piezo-quartz and static weigh scales have superior validity, with piezo-quartz data offering better temporal coverage, data availability, and future geographic coverage. Ultimately, the selection of the best option for providing quality axle load data depends on the relative importance of data quality principles for producing data supporting sound pavement designs and infrastructure management decisions. / May 2017
15

Pesagem em movimento de cargas atuantes em rodovias e seu impacto no desempenho de pavimentos da rede temática de asfalto / Weigh in motion of road loads and their impact in pavement performance of the brazilian Asphalt Tematic Network

Bock, André Luiz January 2016 (has links)
Nas últimas décadas os pavimentos rodoviários brasileiros têm tido seu desempenho comprometido devido a uma série de fatores, entre eles incluem-se não somente o crescente aumento do volume de tráfego de veículos pesados e aumento de sua capacidade de transporte, mas principalmente a circulação com cargas acima dos limites legais estabelecidos, configurando uma situação crítica para a sua adequada durabilidade da estrutura projetada. Paralelamente aos investimentos necessários, é importante também o desenvolvimento de métodos mais racionais de dimensionamento de pavimentos contemplando as especificidades dos materiais empregados e levando em consideração as condições climáticas e, principalmente uma completa e detalhada caracterização do tráfego solicitante. Neste contexto apresentado, a pesquisa insere-se em dois importantes estudos. O acompanhamento construtivo e monitoramento sistemático de desempenho de dois trechos na rodovia BR-448/RS e a continuidade do monitoramento de outros dois na BR-290/RS, trecho em concessão entre Osório e Porto Alegre (Freeway). Estas atividades inserem-se no “Projeto Integrado da Rede Temática de Tecnologia em Asfalto Petrobras/ANP", de abrangência nacional, para desenvolvimento de um novo método brasileiro de dimensionamento de pavimentos O segundo estudo trata-se de um completo monitoramento de cargas na Freeway, através da instalação e operacionalização inédita de um equipamento de pesagem dinâmica de alta velocidade (Hight Speed Weigh-in-Motion – HS-WIM) para determinação do espectro de cargas e posterior análise de sua influência no desempenho de pavimentos. Com ambos os estudos foi possível, além de determinar o espectro de cargas, os carregamentos médios e os níveis de sobrecargas praticados naquela rodovia, verificar como estas cargas influenciam o desempenho do pavimento e confrontar estes dados com as tendências observadas através do monitoramento sistemático dos trechos analisados. Por meio do desenvolvimento do presente trabalho pretende-se contribuir para melhorias na engenharia rodoviária e de tráfego através da inserção de novas tecnologias de monitoramento e fiscalização das cargas transportadas e contribuir com o desenvolvimento de um novo método de dimensionamento de pavimentos flexíveis proposto pela Rede Temática de Asfalto, através do levantamento de dados nos trechos experimentais para desenvolvimento de modelos de desempenho e sua posterior inserção nos modelos de calibração. / In recent decades the Brazilian road pavements have had their performance reduced due to a number of factors, not only the increasing volume of heavy vehicles and increased transport capacity, but mainly the flow with loads above the established legal limits, setting a critical situation for the durability of the designed structure. Alongside the necessary investment, it is also important to the development of more rational methods of pavement design, considering the specificities of the materials used and taking into account the climatic conditions and a complete and detailed characterization of the traffic. In this context, the research was developed to attain two main objectives: the construction monitoring and systematic assessment of performance of two test sections built in BR-448/RS highway and the continuity of assesment of two others previously built in BR-290/RS, between Osório and Porto Alegre (known as Freeway). These activities are part of the "Integrated Project Theme Technology Network Petrobras Asphalt/ANP", a nationwide project aimed at developing a new Brazilian method for pavement design The second objective was to conduct a comprehensive monitoring loads study on the Freeway, by installing and carrying on an unprecedented operation of a dynamic weighting equipment of high speed (High speed weigh-in-Motion - HS-WIM) to determine the loads spectrum and subsequent analysis of the influence on pavement performance. Both studies made possible to determine the loads spectrum, average loads and levels of overloads practiced on that highway, to estimate how these loads affect the pavement performance and to compare these data with the trends observed through the systematic assessment of the analyzed sections. This work aims to contribute to improvements in road and traffic engineering, by introducing new monitoring technologies, monitoring the transported cargo and contributing to the development of a new design method of flexible pavements, a major goal of the Thematic Network of Asphalt, to be achieved through experimental data collection in test sections, the development of performance models and their subsequent insertion in the calibration models.
16

Testing of Rainflow Histograms of Strain for Implementation as a Bridge Weigh-in-Motion Technnique

Johnson, Nephi R. 01 May 2015 (has links)
This research was done as part of a long term project, with the goal to monitor multiple bridges over an extended period of time. Due to the nation’s aging infrastructure and the limited amount of funds to upgrade and maintain it, structural health monitoring (SHM) is very important because it provides in depth information about a structure to be used in decision making. SHM of bridges includes monitoring the effects of traffic loads. This paper discusses the development of a bridge weigh-in-motion (B-WIM) technique that uses the rainflow counting of strain cycles. Typical B-WIM techniques have proven to be accurate but require large algorithms and gauges at multiple locations across the span, and the strain gauge temperature drift must be accounted for. The rainflow B-WIM (RF-BWIM) decreases the processing of the B-WIM and automatically accounts for drift, thus allowing temperature and other analyses of the same bridge to be possible. RF-BWIM also has the potential to decrease the number of sensors required. Strain data taken from an existing long term monitoring system was used to develop the RF-BWIM. The development of the RF-BWIM, as well as a method to determine a virtual gross vehicle weight (C-GVW) used in calculating the RF-BWIM output, is presented.
17

Pesagem em movimento de cargas atuantes em rodovias e seu impacto no desempenho de pavimentos da rede temática de asfalto / Weigh in motion of road loads and their impact in pavement performance of the brazilian Asphalt Tematic Network

Bock, André Luiz January 2016 (has links)
Nas últimas décadas os pavimentos rodoviários brasileiros têm tido seu desempenho comprometido devido a uma série de fatores, entre eles incluem-se não somente o crescente aumento do volume de tráfego de veículos pesados e aumento de sua capacidade de transporte, mas principalmente a circulação com cargas acima dos limites legais estabelecidos, configurando uma situação crítica para a sua adequada durabilidade da estrutura projetada. Paralelamente aos investimentos necessários, é importante também o desenvolvimento de métodos mais racionais de dimensionamento de pavimentos contemplando as especificidades dos materiais empregados e levando em consideração as condições climáticas e, principalmente uma completa e detalhada caracterização do tráfego solicitante. Neste contexto apresentado, a pesquisa insere-se em dois importantes estudos. O acompanhamento construtivo e monitoramento sistemático de desempenho de dois trechos na rodovia BR-448/RS e a continuidade do monitoramento de outros dois na BR-290/RS, trecho em concessão entre Osório e Porto Alegre (Freeway). Estas atividades inserem-se no “Projeto Integrado da Rede Temática de Tecnologia em Asfalto Petrobras/ANP", de abrangência nacional, para desenvolvimento de um novo método brasileiro de dimensionamento de pavimentos O segundo estudo trata-se de um completo monitoramento de cargas na Freeway, através da instalação e operacionalização inédita de um equipamento de pesagem dinâmica de alta velocidade (Hight Speed Weigh-in-Motion – HS-WIM) para determinação do espectro de cargas e posterior análise de sua influência no desempenho de pavimentos. Com ambos os estudos foi possível, além de determinar o espectro de cargas, os carregamentos médios e os níveis de sobrecargas praticados naquela rodovia, verificar como estas cargas influenciam o desempenho do pavimento e confrontar estes dados com as tendências observadas através do monitoramento sistemático dos trechos analisados. Por meio do desenvolvimento do presente trabalho pretende-se contribuir para melhorias na engenharia rodoviária e de tráfego através da inserção de novas tecnologias de monitoramento e fiscalização das cargas transportadas e contribuir com o desenvolvimento de um novo método de dimensionamento de pavimentos flexíveis proposto pela Rede Temática de Asfalto, através do levantamento de dados nos trechos experimentais para desenvolvimento de modelos de desempenho e sua posterior inserção nos modelos de calibração. / In recent decades the Brazilian road pavements have had their performance reduced due to a number of factors, not only the increasing volume of heavy vehicles and increased transport capacity, but mainly the flow with loads above the established legal limits, setting a critical situation for the durability of the designed structure. Alongside the necessary investment, it is also important to the development of more rational methods of pavement design, considering the specificities of the materials used and taking into account the climatic conditions and a complete and detailed characterization of the traffic. In this context, the research was developed to attain two main objectives: the construction monitoring and systematic assessment of performance of two test sections built in BR-448/RS highway and the continuity of assesment of two others previously built in BR-290/RS, between Osório and Porto Alegre (known as Freeway). These activities are part of the "Integrated Project Theme Technology Network Petrobras Asphalt/ANP", a nationwide project aimed at developing a new Brazilian method for pavement design The second objective was to conduct a comprehensive monitoring loads study on the Freeway, by installing and carrying on an unprecedented operation of a dynamic weighting equipment of high speed (High speed weigh-in-Motion - HS-WIM) to determine the loads spectrum and subsequent analysis of the influence on pavement performance. Both studies made possible to determine the loads spectrum, average loads and levels of overloads practiced on that highway, to estimate how these loads affect the pavement performance and to compare these data with the trends observed through the systematic assessment of the analyzed sections. This work aims to contribute to improvements in road and traffic engineering, by introducing new monitoring technologies, monitoring the transported cargo and contributing to the development of a new design method of flexible pavements, a major goal of the Thematic Network of Asphalt, to be achieved through experimental data collection in test sections, the development of performance models and their subsequent insertion in the calibration models.
18

Pesagem em movimento de cargas atuantes em rodovias e seu impacto no desempenho de pavimentos da rede temática de asfalto / Weigh in motion of road loads and their impact in pavement performance of the brazilian Asphalt Tematic Network

Bock, André Luiz January 2016 (has links)
Nas últimas décadas os pavimentos rodoviários brasileiros têm tido seu desempenho comprometido devido a uma série de fatores, entre eles incluem-se não somente o crescente aumento do volume de tráfego de veículos pesados e aumento de sua capacidade de transporte, mas principalmente a circulação com cargas acima dos limites legais estabelecidos, configurando uma situação crítica para a sua adequada durabilidade da estrutura projetada. Paralelamente aos investimentos necessários, é importante também o desenvolvimento de métodos mais racionais de dimensionamento de pavimentos contemplando as especificidades dos materiais empregados e levando em consideração as condições climáticas e, principalmente uma completa e detalhada caracterização do tráfego solicitante. Neste contexto apresentado, a pesquisa insere-se em dois importantes estudos. O acompanhamento construtivo e monitoramento sistemático de desempenho de dois trechos na rodovia BR-448/RS e a continuidade do monitoramento de outros dois na BR-290/RS, trecho em concessão entre Osório e Porto Alegre (Freeway). Estas atividades inserem-se no “Projeto Integrado da Rede Temática de Tecnologia em Asfalto Petrobras/ANP", de abrangência nacional, para desenvolvimento de um novo método brasileiro de dimensionamento de pavimentos O segundo estudo trata-se de um completo monitoramento de cargas na Freeway, através da instalação e operacionalização inédita de um equipamento de pesagem dinâmica de alta velocidade (Hight Speed Weigh-in-Motion – HS-WIM) para determinação do espectro de cargas e posterior análise de sua influência no desempenho de pavimentos. Com ambos os estudos foi possível, além de determinar o espectro de cargas, os carregamentos médios e os níveis de sobrecargas praticados naquela rodovia, verificar como estas cargas influenciam o desempenho do pavimento e confrontar estes dados com as tendências observadas através do monitoramento sistemático dos trechos analisados. Por meio do desenvolvimento do presente trabalho pretende-se contribuir para melhorias na engenharia rodoviária e de tráfego através da inserção de novas tecnologias de monitoramento e fiscalização das cargas transportadas e contribuir com o desenvolvimento de um novo método de dimensionamento de pavimentos flexíveis proposto pela Rede Temática de Asfalto, através do levantamento de dados nos trechos experimentais para desenvolvimento de modelos de desempenho e sua posterior inserção nos modelos de calibração. / In recent decades the Brazilian road pavements have had their performance reduced due to a number of factors, not only the increasing volume of heavy vehicles and increased transport capacity, but mainly the flow with loads above the established legal limits, setting a critical situation for the durability of the designed structure. Alongside the necessary investment, it is also important to the development of more rational methods of pavement design, considering the specificities of the materials used and taking into account the climatic conditions and a complete and detailed characterization of the traffic. In this context, the research was developed to attain two main objectives: the construction monitoring and systematic assessment of performance of two test sections built in BR-448/RS highway and the continuity of assesment of two others previously built in BR-290/RS, between Osório and Porto Alegre (known as Freeway). These activities are part of the "Integrated Project Theme Technology Network Petrobras Asphalt/ANP", a nationwide project aimed at developing a new Brazilian method for pavement design The second objective was to conduct a comprehensive monitoring loads study on the Freeway, by installing and carrying on an unprecedented operation of a dynamic weighting equipment of high speed (High speed weigh-in-Motion - HS-WIM) to determine the loads spectrum and subsequent analysis of the influence on pavement performance. Both studies made possible to determine the loads spectrum, average loads and levels of overloads practiced on that highway, to estimate how these loads affect the pavement performance and to compare these data with the trends observed through the systematic assessment of the analyzed sections. This work aims to contribute to improvements in road and traffic engineering, by introducing new monitoring technologies, monitoring the transported cargo and contributing to the development of a new design method of flexible pavements, a major goal of the Thematic Network of Asphalt, to be achieved through experimental data collection in test sections, the development of performance models and their subsequent insertion in the calibration models.
19

Traffic Monitoring System Using In-Pavement Fiber Bragg Grating Sensors

Al-Tarawneh, Mu'ath January 2019 (has links)
Recently, adding more lanes becomes less and less feasible, which is no longer an applicable solution for the traffic congestion problem due to the increment of vehicles. Using the existing infrastructure more efficiently with better traffic control and management is the realistic solution. An effective traffic management requires the use of monitoring technologies to extract traffic parameters that describe the characteristics of vehicles and their movement on the road. A three-dimension glass fiber-reinforced polymer packaged fiber Bragg grating sensor (3D GFRP-FBG) is introduced for the traffic monitoring system. The proposed sensor network was installed for validation at the Cold Weather Road Research Facility in Minnesota (MnROAD) facility of Minnesota Department of Transportation (MnDOT) in MN. A vehicle classification system based on the proposed sensor network has been validated. The vehicle classification system uses support vector machine (SVM), Neural Network (NN), and K-Nearest Neighbour (KNN) learning algorithms to classify vehicles into categories ranging from small vehicles to combination trucks. The field-testing results from real traffic show that the developed system can accurately estimate the vehicle classifications with 98.5 % of accuracy. Also, the proposed sensor network has been validated for low-speed and high-speed WIM measurements in flexible pavement. Field testing validated that the longitudinal component of the sensor has a measurement accuracy of 86.3% and 89.5% at 5 mph and 45 mph vehicle speed, respectively. A performed parametric study on the stability of the WIM system shows that the loading position is the most significant parameter affecting the WIM measurements accuracy compared to the vehicle speed and pavement temperature. Also the system shows the capability to estimate the location of the loading position to enhance the system accuracy.
20

Integrated transportation monitoring system for both pavement and traffic

Xue, Wenjing 12 June 2013 (has links)
In the passing decades, the monitoring of pavements and passing vehicles was developed vigorously with the growth of information and sensing technology. Pavement monitoring is an essential part of pavement research and plays an important role in transportation system. At the same time, the monitoring system about the traffic, such as Weigh-in-Motion (WIM) system and traffic classification system, also attracted lots of attention because of their importance in traffic statistics and management. The monitoring system in this dissertation combines the monitoring for pavements and traffic together with the same sensing network. For pavement health monitoring purpose, the modulus of the asphalt layer can be back-calculated based on the collected mechanical responses under corresponding environmental conditions. At the same time, the actually strain and stress in pavements induced by each passing vehicle are also used for pavement distress prediction. For traffic monitoring purpose, the horizontal strain traces are analyzed with a Gaussian model to estimate the speed, wandering position, weight and classification of each passing vehicle. The whole system, including the sensing network and corresponding analysis method, can monitor the pavement and the traffic simultaneously, and is called transportation monitoring system. This system has a high efficiency because of its low cost and easy installation; multi-functionality to provide many important information of transportation system. Many related studies were made to improve the prototyped transportation monitoring system. With the assistance of numerical simulation software ABAQUS and 3D-Move, the effect of many loading and environmental conditions, including temperature, vehicle speed, tire configuration and inflation pressure, are taken into consideration. A method was set up to integrate data points from many tests of similar environmental and loading conditions based on Gaussian model. Another method for consistent comparison of variable field sensor data was developed. It was demonstrated that variation in field measurement was due to uncontrollable environmental and loading factors, which may be accounted for by using laboratory test and numerical simulation based corrections. / Ph. D.

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