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Optimum use of the flexible pavement condition indicators in pavement management systemShiyab, January 2007 (has links)
This study aimed at investigating the current practices and methods adopted by roads agencies around the world with regard to collection, analysis and utilization of the data elements pertaining to the main pavement condition indicators in pavement management systems (PMS). It also aimed at identifying the main predictors associated with each condition indicator and the factors that govern pavement structural and functional performance. Development of a new performance index that incorporates parameters or measures related to the main condition indicators (surface defects, roughness, deflection and skid resistance) and establishing the weight to be assigned to each indicator based on the relative impact on pavement condition was also one of the main objectives of this study. Thousands of pavement sections were subjected to thorough testing and inspection over the last few years to collect data pertaining to the main condition indicators. The collected data encompass visual distress survey, deflection measurements, roughness and skid resistance measurements. Collection of various condition indicators was accomplished according to well known international standards. The collected data were processed, tabulated and analyzed for the purpose of development of performance models and to prove certain theories or good practices. / Advanced tools and machines were utilized to collect these data with a high degree of accuracy. The Falling Weight Deflectometer (FWD) was used to collect deflection data for structural analysis. Two Non-contact laser roughness measuring devices mounted on vehicles were heavily used for collecting roughness, texture, and rutting data. Distress data were collected using a manual procedure adopted and standardized at the Pavement Management System Unit of Dubai Emirate. Powerful engineering and statistical softwares were used in the analysis for the purpose of processing the data, back calculating the main parameters pertaining to pavement response, establishing the correlation matrices between various dependent variables and their predictors, and finally, applying linear and non linear regression analysis to develop reliable and predictable deterioration models for the uses of pavement management system. The analysis procedure was supplemented by a vast literature review for the up to date information along within deep investigations and verifications for some of the current practices, theories and models used in pavement design and pavement evaluation with more emphasis on the inherent drawbacks associated to these models and procedures. The study confirmed that pavement condition deterioration and performance can be best predicted and evaluated based on four main condition indicators; First, surface distress to assess the physical condition of the pavements and detect the inherent problems and defects caused by various factors affecting pavement performance. Second; roughness measurements to evaluate the riding quality of the pavement. / Third; deflection to calculate pavement response (stress and strains) and to assess pavement structural capacity and calculating the remaining life, and finally, skid resistance measurement to assess the level of safety and surface texture properties. Thorough study and investigation of the physical condition indicators and the associated parameters, confirmed that pavement distress data are vital elements in each pavement management system. Distress data can be used effectively to identify the main problems associated with pavement performance, causes of deterioration, maintenance measures needed to prevent the acceleration of the distress, the rehabilitation schemes needed to improve the pavement condition and finally to prepare maintenance work programs and to estimate the annual maintenance needs under an open or limited budget. Alligator cracking was found to have the heaviest impact on pavement condition. Distress density, probable causes of deterioration and distress propagation rate are the required parameters in PMS. Roughness was found to have a basic influence on pavement condition and the type of selected treatment. The use of Roughness data in terms of International Roughness Index (IRI) can be optimized in PMS by using this indicator in the following forms: / Roughness, as an objective measure, can be used as a good performance predictor of the current riding quality of pavements in service and reflects the inherent imperfections and built-in irregularities embodied in the road pavement surface. Roughness measurement can be used as a reference to establish construction specifications and provides through the PMS system an organized feedback approach to correct the persistent design deficiencies detected after road construction. Roughness can be used effectively in the planning process for maintenance works and to select the candidate sections through calculating the functional remaining life based on the estimated terminal value using Roughness-Age, Roughness-ESAL, and Roughness-PSI models. Lane–IRI along with the Difference between the left and right wheel IRI values, termed as “ Yaw” are the most suitable forms to be used in PMS to report about roughness characteristics. Yaw term can be used effectively to report or feed back about geometric imperfections that exist on the road surface such as improper cross slope, shoving and the probable drainage problems. The roughness cumulative distribution curves can be used as a planning tool in PMS to report at the network level. These curves indicate the network health and the required funding at different level of risks, so proactive measures can be taken and the required budgets can be made available. / Deflection data were found to form a basic component of the PMS. It was found that these data can be used at both network and project levels. Direct deflection measurements were found Not to be the ideal form to report about structural capacity at the network level. It is rather can be used at project level to detect weak spots and critical pavements layers. At the network level, the back calculated parameters from deflection basin such as Pavement Modulus (Ep), Asphalt and Pavement Curvature (CUR), Cross Sectional Area and the other deflection basin characteristics are much more appropriate for reporting about pavement structural conditions and calculating the structural remaining life in PMS. The design deflection and curvature that characterize the pavement have been found to be calculated based on the mean along with the two times the standard deviation of the measured data. The Effective Structural Number (SNeff) was found to have good correlations with the Total Pavement Thickness (Ht), the value of the deflection measured at the center of the loading plate ( D0 ) and the difference between D0 and the deflection measured at 450mm from the center of the loading plate ( D0 - D450 ). The first two variables were found to account for more than 92% of the structural capacity prediction model. / Traffic variable in terms of the accumulated standard repetitions (ESAL) was found to account for more than 60% of the deflection model predictability. Other variables such as E value, asphalt and base layer thicknesses can improve the predictability of the model if included. The concept of the relative value of effective pavement modulus to the original pavement modulus (Eeff/E0) was found to gives a reliable representation about the exhausted and the remaining life of the in-service pavement structure. The study showed that the pavement is reported to be structurally failed, when the effective asphalt or pavement modulus is about 20 - 35 % of its original design value which is equal to the modulus of the unbound material. It was also found that when the area of the fatigue cracking and the patching distresses exceeds 17% of the total pavement section area, or the depth of rutting is more than 15mm, the pavement is reported to be structurally failed and major rehabilitation or reconstruction should be applied. Skid resistance can be reported in the form of International Friction Index (IFI), as a well defined universal index, along with other two numbers; F60 Friction (Microtexture) related number measured at 60 km/h velocity and Macrotexture related number and Vp, which constitute the IFI index can be used in Pavement management system applications to report about skid resistance characteristics and the network level of safety. These three figures can be used to report about pavement condition, accidents, airports operations, and maintenance management surveys. / In this study, new methods and models were developed and suggested to be used in PMS as an alternative to the current available methods which were found to be impractical in certain cases. Finally, further research efforts are recommended to explore the uses of other parameters in particular those related to deflection basin analysis, cross sectional area, curvature, and pavement moduli. Skid resistance testing and reporting method should be subjected to further research works for the purpose of standardizing reporting methods, identifying the relative impact of main predictors i.e. megatexture, macrotexture and microtexture components and to develop performance models.
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Vilniaus miesto gatvių asfalto dangos funkcionavimo trukmės tyrimai ir vertinimas / Researches and analysis of functional duration of asphalt pavements on the streets of Vilnius cityŽiliūtė, Laura 20 June 2008 (has links)
Šiame darbe pateikti duomenys apie Vilniaus miesto gatvių tinklą, jų techninius parametrus, trumpai apžvelgiama Vilniaus miesto gatvių būklė. Nagrinėti pažaidų tipai gatvėse su asfalto danga, pažaidų atsiradimo priežastys bei jų nustatymo metodikos, naudojamos įrangos. Nurodomi transporto eismo intensyvumo matavimo metodai, įranga. Atlikta analizė vizualiai nustatytų asfalto dangos pažaidų vienuolikos gatvių, esančių Vilniau mieste, bei transporto eismo intensyvumo matavimų, naudojant automatinį skaičiuoklį – klasifikatorių Marksman 660. Įvertinta asfalto dangos pažaidų bei transporto eismo intensyvumo priklausomybė. Atsižvelgiant į darbe atliktą analizę, sudarytas prioritetinis Vilniaus miesto remontuotinų gatvių sąrašas. / In this work there are supplied the net of Vilnius city streets, its engineering parameters, condition of streets in Vilnius has been overlooked briefly. There has been analysed types of defects in streets with asphalt pavement, reasons for origination of defects and methods for identification, usable equipment. Methods of measurement of traffic intensity and usable equipment has been also indicated. There has been analysed defects of asphalt pavement, which had been defined visually in eleven streets in Vilnius city, and measurements of traffic volume using the counter-sizer Marksman 660. Dependence of asphalt pavement defects and traffic volume has been estimated too. According to the analyse of this work, there has been done the list of priority for repairing these eleven streets in Vilnius city.
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Využití dat pro systém hospodaření s vozovkou na silnicích II. a III. tříd k posouzení účinků vnějších vlivů na povrch vozovek / Usage of data for the pavement management system on roads II. and III. classes to assess the effects of external influences on the road surfaceSkořepová, Eliška January 2022 (has links)
The master thesis is focused on sorting collected primary data, their subsequent analysis and further comparison in the field of road defects. The collection of pavement failures was done by visual inspection with its recording to a computer for the pavement management system. The data later underwent detailed analysis with the aim to find a potential link between the road defect and the location of the damaged section. The study took place on 2nd and 3rd class roads in the Liberec Region, with special focus on those located near forests. The data collection itself took place in the Liberec Region in 2021. The processing and subsequent evaluation of collected data was done thanks to the availability of comparable data sets from 2014 and 2019 to 2021, so the development of road defects of the selected road network in relation to the surrounding afforestation could be assessed. The last part of this master thesis compares results in different classification levels, time periods and levels of afforestation.
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Comparison of Several Project Level Pavement Condition Prediction ModelsNimmatoori, Praneeth January 2009 (has links)
No description available.
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Aplikace systému hospodaření s vozovkou (SHV) na silnicích II. a III. třídy Libereckého kraje / Aplication ofŽůrek, Jakub January 2020 (has links)
This master thesis deals with the pavement management system as a tool for a management and maintenance of the roads in the Liberec region. The aim is to collect road failures within the network pavement management system level on roads of 2nd and 3rd class. The resulting data will be used for evaluate pavement condition and make plans of pavement maintenance and rehabilitation in variants. Furthermore, the thesis deals with individual variants in the process of data evaluation when evaluating their suitability and accuracy. The theoretical part summarises the information needed to understand the functioning of the road management system, as well as a description of the software used to collect and subsequent work with the data. In the practical part are presented results of the thesis and moreover the questions arising from the goals set are answered.
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Aplikovaný systém hospodaření s vozovkou pro silnice II. a III.třídy v Královéhradeckém kraji / Pavement Management System Applied on Roads of 2nd and 3rd class in Region of Hradec KrálovéNowak, Tomáš January 2014 (has links)
Master‘s thesis deals with pavement management system applied on roads of 2nd and 3rd class in region of Hradec Králové. Its task is to collect failures of pavement, evaluate pavement condition and make plans of pavement maintenance and rehabilitation in variants. One of tasks is also to evaluate attitude of pavement management system in regional level, but also to evaluate the contributions and weaknesses of systematic steps and attitude of access of stakeholders.
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