Investigation of Feasible Pavement Design Alternatives for WisDOT

The current pavement design and selection process of WisDOT for all new pavements or reconstructions of existing pavement structures provides for the design of one asphaltic concrete (AC) and one portland cement concrete (PCC) pavement alternative. Life-cycle costs analyses are then used to determine the preferred alternative for construction. Previous restrictions in the WisDOT pavement selection process have essentially excluded the construction of thick AC (AC thickness \u3e 150 mm) and thin PCC (PCC thickness \u3c 225 mm) pavements and thus the validity of current life-cycle cost inputs for these pavement types is under question. This report presents a performance analysis of existing thick AC and thin PCC pavements constructed in and around Wisconsin. The performance trends developed indicate current design assumptions utilized by WisDOT, related to the expected service life to first rehabilitation of AC and PCC pavements, may also be used for thick AC and thin PCC pavements

Effects of Subsurface Drainage on Pavement Performance

This report evaluates the effects of subsurface drainage features on pavement performance through a program of inspection and testing of the subsurface drainage features present in the Long-Term Pavement Performance (LTPP) SPS-1 and SPS-2 field sections. The report will be of particular interest to engineers in the public and private sectors with responsibility for the design, construction, and rehabilitation of highway pavements

EVALUATION PAVEMENT DISTRESSES USING PAVEMENT CONDITION INDEX

Pavement deterioration is resulted by both environmental and structural causes. It is difficult to maintain the road on the same specification that was owned at the opening and problems start to appear represented in the pavement cracks, holes and undulations and so on. Recognizing defects and understanding their causes helps us rate pavement condition and select cost-effective repairs. Periodic inspection is necessary to provide current and useful evaluation data. It is recommended that ratings be updated every year. Maintenance is an essential practice in providing for the long-term performance and the esthetic appearance of an asphalt pavement. The purpose of pavement maintenance is to correct deficiencies caused by distresses and to protect the pavement from further damage. A condition rating of the pavement will help determine what pavement maintenance technique is necessary. A methodology was proposed to investigate the pavement condition; this study focuses on flexible pavement. A manual survey is performed following ASTM D 6433. The pavement is divided into sections. Each section is divided into sample units. The type and severity of sample distress is assessed by visual inspection of the pavement sample units and the quantity of each distress is measured. Typically, this procedure requires a team of at least two engineers. The pavement evaluation results from the manual PCI survey revealed that all sections of road were fair condition. Considered the section of road that surveyed, describing the condition pavement of the all road. The pavement that has been studied at Koums area would seem to require maintenance. Thick overlay (sometimes called surface treating) is needed in a comprehensive pavement

Effect of Proportion of Missing Data on Application of Data Imputation in Pavement Management Systems

Missing data are commonly found in pavement condition/performance databases. A common practice today is to apply statistical imputation methods to replace the missing data with imputed values. It is thus important for pavement management decision makers to know the uncertainty and errors involved in the use of datasets with imputed values in their analysis. An equally important information of practical significance is the maximum allowable proportion of missing data (i.e. level of data missingness in the pavement condition/performance records) that will still produce results with acceptable magnitude of error or risk when using imputed data. This paper proposes a procedure for determining such useful information. A numerical example analyzing pavement roughness data is presented to demonstrate the procedure through evaluating the error and reliability characteristics of imputed data. The roughness data of three road sections were obtained from the LTPP database. From these data records, datasets with different proportions of missing data were randomly generated to study the effect of level of data missingness. The analysis shows that the errors of imputed data increased with the level of data missingness, and their magnitudes are significantly affected by the effect of pavement rehabilitation. On the application of data imputation in PMS, the study suggests that at 95% confidence level, 25% of missing data appears to be a reasonable allowable maximum limit for analyzing pavement roughness time series data not involving rehabilitation within the analysis period. When pavement rehabilitation occurs within the analysis period, the maximum proportion of imputed data should be limited to 15%

Mechanistic Analysis and Economic Benefits of Fiber-Reinforced Asphalt Overlay Mixtures

Among the various distresses in flexible pavement structures, rutting and fatigue cracking can be accounted as two of the major distresses that need to be addressed by pavement engineers. Laboratory tests, such as four-point bending beam and flow number are utilized to characterize the rutting and cracking resistance of flexible pavements. Various construction practices are introduced to reduce the effect of fatigue and rutting in pavement structures. One of such methods is applying fibers to the asphalt mixture to prolong the serviceability and the performance of the pavement structures. The use of fibers is applicable to freshly constructed pavements as well as in the pavement rehabilitation and maintenance work, such as overlay. This paper primarily analyses the application of fibers in the overlay of pavements. The two major cases of the pavement with original asphalt overlay and the one with fibers mixed asphalt overlay is considered utilizing a developed testing program where the mechanistic analysis as well as the economic effectiveness is evaluated. 3D move analysis software package is utilized extensively as a means of mechanistic analysis tool. It is found that the fiber mixture pavement overlay had a higher pavement life than the ordinary asphalt overlay. In addition, the cost effectiveness in terms of fatigue and rutting of fiber-reinforced overlay structures were 4.4 and 4.1 times the unmodified mixtures, respectively. The use of fibers in the overlay of pavement resulted in higher pavement life with a high cost effectiveness

Statistics and Artificial Intelligence-Based Pavement Performance and Remaining Service Life Prediction Models for Flexible and Composite Pavement Systems

In their pavement management decision-making processes, U.S. state highway agencies are required to develop performance-based approaches by the Moving Ahead for Progress in the 21st Century (MAP-21) federal transportation legislation. One of the performance-based approaches to facilitate pavement management decision-making processes is the use of remaining service life (RSL) models. In this study, a detailed step-by-step methodology for the development of pavement performance and RSL prediction models for flexible and composite (asphalt concrete [AC] over jointed plain concrete pavement [JPCP]) pavement systems in Iowa is described. To develop such RSL models, pavement performance models based on statistics and artificial intelligence (AI) techniques were initially developed. While statistically defined pavement performance models were found to be accurate in predicting pavement performance at project level, AI-based pavement performance models were found to be successful in predicting pavement performance in network level analysis. Network level pavement performance models using both statistics and AI-based approaches were also developed to evaluate the relative success of these two models for network level pavement performance modeling. As part of this study, in the development of pavement RSL prediction models, automation tools for future pavement performance predictions were developed and used along with the threshold limits for various pavement performance indicators specified by the Federal Highway Administration. These RSL models will help engineers in decision-making processes at both network and project levels and for different types of pavement management business decisions

Experimental feasibility study of using date palm oil as a bitumen Bio-Modifier in HMA pavement

This paper examines the effects of Date palm oil as a bitumen modifier on the compressive strength of bitumen and hot mixed asphalt (HMA) pavement. Date palm oil contains anti-oxidant isomers that have the potential to enhance the performance and durability of bitumen. The compressive strength test of asphalt pavement mixed with Date palm oil was performed in accordance with British Standards BS 1881: Part 116: 1983. The cube specimens of asphalt pavement were manufactured mixing with 0%, 2.5%, 5%, 7.5%, and 10% of Date palm oil out of total sample mass. The experimental results suggested that Date palm oil as a bitumen modifier reduced the compressive strength of HMA pavement. The findings of this paper urge for further experiments to understand the effects of Date palm oil on the asphalt pavements under long-term traffic load, environment and surface drainage

Probabilistic prediction of asphalt pavement performance

Variability of pavement design parameters has always been a concern to pavement designers and highway agencies. A robust pavement design should take into account the variability of the design inputs and its impact on the reliability of the design. In this study, the variability effect of thickness and stiffness of pavement layers was investigated. The variability of these parameters was described by their mean values, standard deviations and probability distribution functions. Monte Carlo Simulation method was utilised to incorporate variability of the design parameters and to construct the probability distribution function of the outputs. KENLAYER software was used to calculate pavement response at predetermined critical locations; pavement reponse was then used to predict pavement performance regarding permanent deformation, bottom-up and top-down fatigue cracking by using the mechanistic empirical pavement design guide (MEPDG) models. A Matlab code was developed to run that analysis and obtain the probability distribution function of pavement performance indicators over time. It was found that the variability of pavement layer thickness and stiffness has a significant impact on pavement performance. Also, it was found that not only the mean of the predicted performance indicators is increasing over time, but the variance of these indicators is also increasing. This means that pavement condition cannot be described by the mean values of the indicators but by the probability distribution function which can describe pavement condition at any reliability level

Software development for flexible pavement thickness design based on aastho and road note 31

Nowadays, road and surface failure has become a critical issue in our country on the flexible pavement which reflects to a bad quality and error during design stage. The thickness design of flexible pavement has become crucial element in the overall efficiency of highway structure system to give a good performance and high serviceability under a traffic loading during the expected design period. The objectives of this study are to develop flexible pavement thickness design software for AASHTO and Road Note 31 by using Visual Basic 6.0. The result comparison between both methods was carried out shown in different of thickness and different percentage of cost evaluations between AASHTO and Road Note 31. This computer software could produce the design thickness of each layer for flexible pavement structure in graphical layout for both design methods. Therefore, the users can easily analyze and compared the result obtained to select the best design alternative between AASHTO and Road Note 31 based on cost and thickness different. The result analysis obtained from this computer software also can be saved and view in a report file to be printed or keep as soft copy for reference in the future. Besides, the result analysis obtained by this computer software is also been compared with the manual calculation (theory) and shown that the computer software has the same and exact result with the manual calculation (theory). Thus, the performance of this computer software was successful tested and validated. Therefore, computer software of flexible pavement thickness design is a very useful tool in highway engineering especially to design the thickness of flexible pavement. By applying the computer program, the design stage can be made in a very short time period of design process and help to minimize the error factor compare to manual calculation or conventional method. Computer software also can give a high accuracy and quality of result for pavement thickness design