Search

Cold-applied asphalt mixtures are often used for pavement repair, primarily because of the small quantities involved and/or the unavailability of hot-mixed asphalt. These cold-applied mixtures have poorer rutting resistance than hot mix asphalt because additives, often solvent, are required to provide adequate workability for them to be placed at ambient tempera-tures. This study primarily evaluated the rutting performance of nine commercial cold mix asphalt repair materials. Both laboratory wheel tracking data and field rutting performance were used in the evaluation with the focus on identifying suitable materials for repairing airfield pavements subjected to high-tire-pressure aircraft traffic. The commercial products included traditional cutback cold mixes as well as water-activated repair materials. Results from both laboratory and field rutting measurements showed that the water-activated materials outperform the products containing solvent. However, none of the commercial products achieved the target threshold of less than 1 in. rutting after 100 passes of simulated F-15E aircraft traffic. The laboratory wheel-tracking measurements proved to be a good indicator of field performance.

Road agencies worldwide are investing billions of dollars on road maintenance. Pavement management system is often used to forecast the pavement maintenance cost and for prioritisation of the road sections for rehabilitation. This paper examines an approach for forecasting road network maintenance budget using road network condition as a basis for estimating future maintenance cost. The study establishes the relationship between the road pavement maintenance budgets with the pavement condition indices for road networks for several local government authorities in Southeast Queensland. A budget projection model will be developed using the maintenance cost and condition indices relationship. In addition, a pavement sustainability index will also be developed to demonstrate the gap in the maintenance funding. The budget projection model enables local councils to benchmark their maintenance expenditure and road network condition with other councils nationwide.

Automated and semi-automated pavement distress surveys are being used increasingly to collect pavement condition data. This data, along with other information, is used to measure pavement performance and support pavement maintenance, preservation, and rehabilitation decisions. Generally, these automated and semi-automated systems consist of image capturing technology (i.e., hardware) and image processing and analysis algorithms (i.e., software). This paper provides a review of quality assurance practices for automated and semi-automated pavement condition surveys, including quality of images, accuracy and repeatability of measurements, data delivery requirements, equipment calibration, and control and verification sites. The information on these practices was obtained through a review of seven request for proposals (RFPs) issued by seven state departments of transportation (DOTs) between 2010 and 2015, and supplemented by a review of three manuals for these surveys.

Boston Logan International Airport (BOS) was the first major airport in the United States to incorporate warm mix asphalt (WMA) into asphalt concrete specifications for both runway and non-runway locations. With the increase in wide-body aircraft in the 1990s, rutting of the airside pavements at BOS became a problem. From 1995 to 2003, attempts were made to address the rutting problem by “stiffening” the asphalt mixes. This led to moisture-sensitive mixes, and in the early 2000s, stripping of the asphalt became an issue. Several WMA projects were completed at BOS between 2006 and 2015. Initially, non-WMA control sections were used in critical locations to provide a baseline for evaluating the rutting performance of WMA sections. The first WMA project, in 2006, was the placement of a WMA binder course on the Terminal C alleyway. In 2007, a 150-mm-thick (6-inch-thick (alternating 2-75 mm (2-3 inch) and 1-150 mm (1-6 inch lift)) WMA test strip was included as part of a mill and overlay research project on Taxiway A. In 2008, 24,000 tonnes (26,000 tons) of WMA was used as a part of the rehabilitation of Runway 22L. This project consisted of a 200-mm (8-inch) inlay on the outboard sections of the runway. In 2009, a larger project—50,000 tonnes (55,000 tons)—was constructed for rehabilitation of Runway 9-27, which consisted of a WMA overlay 75 to 175 mm (3 to 7 inches) thick. The ease of WMA compaction was demonstrated along with reduced emissions and energy savings. Also in 2009, WMA was used in the extension of Taxiway Delta at Logan, 36,000 tonnes (40,000 tons). Additionally, new Taxiway G had 250 mm (10 inches) of WMA placed on newly constructed portions of the taxiways, and existing Taxiway C received a 75-mm (3-inch) inlay of WMA. All of the projects at BOS used Sasobit technology and also incorporated from 15 to 20 percent reclaimed asphalt pavement (RAP). The WMA was placed and compacted in maximum 100-mm (4-inch) lifts, whereas 75-mm (3-inch) lifts are typical. A performance grade (PG) 64-28 virgin binder with 4 percent latex modifier and 1.5 percent Sasobit by weight of binder was used for all projects. An anti-stripping additive consisting of 1 percent lime was added to the mixture to alleviate prior issues with moisture sensitivity. This paper describes the process used to evaluate the potential of WMA for airside pavements, along with the lessons learned from asphalt production and placement. The results of condition monitoring from a variety of production sections are presented along with recommendations for the successful use of WMA.

Taipei urban road project has been converted the new conservation-based into the maintenance-based. After completed the road smooth project, the road maintenance authority should face the primary issue is “How to improve the performance of the road maintenance and ensures the implementation of the road smooth project”. Therefore, this study focuses on the characteristics of urban roads to reconstruct urban road maintenance management model. It uses the routine road inspection system to obtain the actual pavement performance indicators (PCI and IRI). Then, it utilizes the self-build maintenance management information platform to control the overall pavement maintenance tasks. Finally, it uses the best of theory and decision tree to evaluate the first priority section of roads to maintain, and the assessment results can provide decision-makers as a maintenance strategy selection and the reference of budgeting.

Pavement smoothness is one of the performance measures utilized for pavement maintenance and rehabilitation strategies. The International Roughness Index (IRI), a widely used indicator of pavement smoothness, is required for the Federal Highway Administration’s (FHWA’s) Highway Performance Monitoring System (HPMS). It has also been adapted as a functional performance characteristic in Mechanistic-Empirical Pavement Design Guide (MEPDG), now rebranded as the AASHTOWare Pavement ME Design. The local calibration of IRI prediction model for jointed plain concrete pavements (JPCP) in AASHTOWare Pavement ME Design software requires actual cracking, faulting and spalling measurements, which are not always collected or available with the state highway agencies (SHAs). The primary objective of this study is to examine if the JPCP IRI model can be locally calibrated without doing a local calibration of the primary distress prediction models associated with the IRI model. In this study, the local calibration of IRI model for JPCP pavement systems is performed using two approaches: the coefficients of IRI model are calibrated using (1) locally-calibrated and (2) nationally-calibrated faulting and transverse cracking model predictions. The accuracy of IRI model predictions using both approaches is evaluated and discussed with a focus on achieving reliable smoothness predictions in a cost-effective manner. Comparable accuracy improvement was achieved when Approach 1 was employed in the local calibration of IRI model compared to Approach 2.

The remaining life is usually taken into account for pavement maintenance or reconstruction. To determine the optimal reconstruction time of a certain composite airport pavement, the authors used 3 kinds of methods to predict the remaining life, respectively based on a former Federal Aviation Administration (FAA) design standard called as Layered Elastic Design Layered Elastic Design Federal Aviation Administration (LEDFAA), Airport Pavement Design Method of China (APDMC) and Pavement Condition Index (PCI) regression model. According to the in-situ data of Heavy Weight Deflectometer (HWD), PCI and air traffic volume in the past several years, the pavement remaining life of the composite airport pavement was predicted using the above three methods. The prediction results and their comparison are presented as well.

The snow roads at McMurdo Station, Antarctica, are the primary transportation corridors for moving personnel and material to and from the airfields servicing intra- and inter-continental air traffic. The majority of the road system is made of snow overlying a snow and ice subsurface. However, at the Scott Base Transition (SBT), the aggregate road leading from Scott Base transitions from the landmass of Ross Island on to the ice shelf and becomes a full depth snow road. Because of the transition between materials, the topography of the area, and extensive use during the austral summer, the SBT is prone to problems unique to that portion of the McMurdo road system and requires specific maintenance activities to remain passable during periods of high temperatures. The SBT area is divided into two subsections. One is the land transition, a soil- or aggregate-surfaced road underlain by permafrost, and the other is the ice transition, a snow-surfaced road underlain by snow and ice. The two sections of the SBT need entirely different construction and maintenance techniques to maintain road surface conditions that will support vehicle traffic. This paper presents some of the issues at the transition area along with maintenance and drainage control measures to alleviate them.

In order to limit heat intake in the ground underneath pavements, high albedo surfaces can be used in cold regions to mitigate permafrost degradation. In this study, experimental sections at Site Experimental Routier de l’Universite Laval (Quebec, 2014), on the Alaska Highway (Beaver Creek, Yukon, 2012 and 2014 and at km post 1786, Yukon, 2014), and in Tasiujaq (Nunavik, Quebec, 2015) were used to document the effectiveness and durability of high albedo surfacing materials. The test sections were equipped with thermistors and data loggers recording surface temperatures. Albedo and skid resistance were also monitored at these sections. In addition to the experimental sites, several albedo measurements were made on asphalt surfaces to develop a relationship between albedo and pavement age.

A total of 137 runways from 107 general aviation airports across the state of Kansas were surveyed in 2008 to assess runway pavement condition in terms of the Pavement Condition Index (PCI). Approximately 68% of the sections surveyed were in “good” to “satisfactory” condition. About 21% of the sections studied were in “fair” condition. Overall, the condition of the network can be rated as “satisfactory.” Deterioration prediction models were developed for the asphalt and concrete surface types. The results show that as much as 44% of the network could have a “fair” rating by 2013 if the sections receive only routine maintenance. The budgeting report developed show that the 108 runways of the 78 general aviation airports eligible for federal funding could be brought to a “satisfactory”rating or above (i.e. average PCI ≥ 70) by spending approximately $15 million annually for five years.

Berming is a common nationwide practice for pavement shoulder maintenance. Quality berming improves the capacity of pavement shoulders and prevents traffic accidents. Results of a nationwide survey show that there is a major desire to improve the safe and effective berm compaction. Emerging new equipment is being developed by Ohio DOT in-house and private industry that uses self-weight and vibratory plate to compact berm materials. An experimental study was conducted on four types of berm materials to evaluate the compaction effects using proctor or vibratory compaction. The effects of compaction energy level were evaluated by measuring the physical, mechanical and electrical properties. Particularly, NDTs were conducted to identify the best indicator on the quality of compaction. The experimental results indicate that vibratory compaction is effective for crushed limestone berm. The asphalt coating on RAPs might reduce the effectiveness of vibratory compaction. Natural soil berm is not well compacted by vibratory compaction. Heat treatment of RAPs up to 60°C did not significantly increase the material compaction or inter-particle adhesion. Wave speeds and Young’s modulus are found to be sensitive indicators for compaction energy levels. The electrical properties, which Ground Penetrating Radar is based on, are not sensitive to different compaction energies.

In 1999, the Arkansas State Highway and Transportation Department (AHTD) began an ambitious program to rehabilitate over 300 miles of Interstate in 5 years. As part of this rehabilitation program, approximately 270 miles of deteriorated concrete pavement was rubblized and overlayed in an attempt to provide a sustainable alternative to traditional removal and replacement of the pavement structure. Many of the pavements constructed during this program are exhibiting a severe level of cracking. Most of these severely cracked asphalt pavements are located west of Conway on Interstate 40; while the rubblized pavements east of Little Rock on I-40 and I-30, which were constructed at virtually the same time, exhibit much less cracking. In this research, two interstate sections are compared. One section was evaluated as “good” condition and the second “poor” condition. A full forensic analysis included a review of the job diaries, rutting and cracking development over the life of the pavement, mix design, mixture testing from cores, and binder testing from cores. Several properties are currently being evaluated and discussed with AHTD in order to prevent future premature deterioration of the state highway network.

As part of a major rehabilitation program in 2001, several pavement sections of the Arkansas Interstate system was rubblized and overlayed. Recently, some of these sections west of Little Rock on Interstate-40 (I-40) experienced severe distresses (cracking, potholes, and roughness). However, I-40 east of Little Rock and I-30 west of Little Rock, reconstructed virtually at the same time, have exhibited no noticeable distresses. The objective of this study is to evaluate root causes of the premature failures of these pavements. To this end, the current pavement condition, historical data, and field core samples have been collected for developing a forensic evaluation framework. Pavement performance data extracted from an Automated Road Analyzer (ARAN) has been analyzed to evaluate the severity of the distresses. Toward establishing correlations, if any, candidate parameters influencing the aforementioned distresses will be gathered from structural and mix design sheets, construction and layout activities, in- service traffic and environmental conditions, interviews, and subgrade soil profiles. The collected core samples will be examined for defects and layer thicknesses, and they will be tested for mechanistic performance evaluation. The findings of the study can be used as a good pavement management tool for timely pavement maintenance actions and for constructing longer lasting pavements. This paper outlines the preliminary steps toward completion of this study.

As a common distress in asphalt pavements, rutting is a primary influencing factor in cases of hydroplaning on rainy days. During hydroplaning events, steering stability performance of vehicles is drastically reduced. Based on analysis of the lateral stability and the steering stability of vehicles traveling on the water's surface while hydroplaning, this paper presents a theoretical analysis for rutting length and depth severity classification. Through creation of a vehicle dynamics model and the use of CarSim, the theoretical variations of lateral offset and lateral acceleration under different speeds were simulated. Through this analysis, it was found that when a vehicle's speed exceeds 80 km/h, the lateral offset and lateral acceleration of the vehicle will increase noticeably and will exceed the safety threshold. In addition, for a given rutting scenario, an interaction effect among rutting depth, rutting length, and vehicle speed is also apparent. Ultimately, a vehicle's lateral offset and lateral acceleration under different rutting depths are recommended for use as factors/indicators of rutting length.

This paper talks about the basic the practical requirements for pavement maintenance of Liaoning province (in northeast China). This paper presents research involving asphalt pavement distresses of six natural districts, and then analyses the types, characteristics and causes of pavement distress that exist in ordinary roads and freeways in different areas. Finally, it compares the two kinds of highways. The statistically analytical results would be regarded as the important reference for pavement maintenance systems.

For a fast treatment of winter distresses, which minimizes the adverse influence of the treatment work on traffic safety and traffic flow, a prefabricated, rollable pavement was developed that is based on a textile-reinforced concrete with short fiber. A high tensile strength and ductility can be expected. Through an oriented design and structuring of the surface, the skid resistance, drainability, and resistance to removal of aggregates can be optimized. This paper provides a basis study on this innovative road surface. With this technique, winter distresses can be removed within a few hours. The new road surface can be opened to traffic as soon as possible. Therefore, it has the potential to contribute to durable road structures and sustainability of road engineering.

The National Highway pavement management system (PMS) in Korea is currently operated by the Ministry of Land, Infrastructure, and Transport Affairs (MOLIT) for efficient use of the budget through proper pavement maintenance. The PMS database system was developed in Excel spreadsheet for each road's history such as pavement material, maintenance method, and pavement conditions. In this study, the authors design a new PMS database system using geographic information system (GIS) technology for national highways to overcome the restrictions of the existing PMS. The newly designed PMS database system can provide pavement-related information more effectively than the previous PMS system. Also, it can secure the reliability of the pavement material for performing research and evaluating the exact pavement conditions.

As oil and gas infrastructure is developed, it has become increasingly important for the roadway users (heavy haulers) to obtain release from their PennDOT roadway bonds as quickly and efficiently as possible. Heavy roadway users are interested in being released from permits on many roads across the Commonwealth of Pennsylvania to free resources for additional infrastructure construction and reduce liability for repair of damages. This presentation would serve to discuss the release process currently being used in PennDOT District 12-0. The process overview will include a discussion of the release requests, video review procedures, coordination within the District, and recommendations on best practices to achieve a timely release. In some cases, the roadway has been damaged by the users and repairs are required prior to release of the roadway bond. This presentation will also discuss the coordination required when road damage has been determined to be caused by a single and/or multiple user(s). This overview will conclude with a case study of the SR 3009 (Tom's Run Road) repair and overlay in Greene County. This project provided for the repair and installation of base repair and a new overlay on five segments (4.0 km, 2.5 miles) of state-maintained roadway. The project included coordination with two roadway contractors, six different roadway users and PennDOT staff, both in the District Office and in the Greene County Maintenance District. Hundreds of tons of asphalt were installed to provide a safe and reliable roadway to the public. The final result was a cost-controlled product that satisfied both the permit holders and PennDOT and resulted in the release of associated bonds.

State and local Departments of Transportation, who have primary responsibility for the upkeep of their roadway pavement, must do so under tight budgets. At the expense of lower functioning roads (such as urban and rural collectors), these agencies tend to focus more of their maintenance and operations budget on high-volume roads - such as freeways and multilane highways - due to their importance. However, municipal officials responsible for the maintenance of collector roads are still expected to provide pavements of acceptable quality to the public, but they must do so under even tighter budgets. This paper presents a comparative analysis of the effectiveness of two pavement maintenance and rehabilitation techniques for municipal roads. One is the mill-and-overlay method, and the other is a resurfacing technique called NovaLite. The HDM-4 pavement management software was used to perform the analysis on 5th Street in downtown Chattanooga, which is under the jurisdiction of the City of Chattanooga Public Works Department, a municipal agency. The results of the analysis indicate that NovaLite is superior to mill-and-overlay in initial cost, time and ease of construction, and extent of disruption of traffic. Even when life cycle costs are considered, the analysis also shows that NovaLite maintains its advantages in cost and effectiveness, suggesting a way forward for cash-strapped municipalities.

Pavement preservation is recognized as a means to a lower life cycle cost of a road asset; but, possibly not all surface distress data are documented and kept to further enhance a beneficial decision for the best treatment at the proper time. This paper presents a study to identify the types of treatments used in Alaska and how the treatments had performed. Forty-four road sections in Alaska that had received a pavement preservation treatment were surveyed in person along with data available from the Alaska Department of Transportation and Public Facilities (AKDOT&PF). The PASER manual for asphalt roads was used to evaluate the distresses for the road sections. Different treatments provided varied improvement of pavement life, which is also consistent with the findings from parallel research efforts of literature and survey conducted by the research team. In addition, pavement failure modes in different regions of Alaska are different. The same pavement preservation treatments may be applied to different regions but to prevent or mitigate different failure modes. Use of some treatments (for example, chip seals) should be considered job-specifically. There is a need to create a pavement preservation database and keep good records of current and future pavement preservation projects for better evaluating and applying them.

Microwave heating technology has been adopted in asphalt pavement maintenance to reduce the total cost resulting from the energy consumption. In this paper, laboratory preparation and microwave heating tests of carbonyl iron powders (CIPs)/asphalt binder were carried out. The modeling procedure, microwave heating efficiency and the properties of the CIPs/asphalt binder - such as penetration, softening point and ductility - were studied. The results show that microwave heating efficiency of CIPs/asphalt binder is enormously higher than that of ordinary asphalt binder. Adding a certain amount of CIPs can improve the asphalt binder's resistance to deformation at high temperature. All of these can put forward a theoretical basis to design asphalt mixtures suitable for use in snow and ice removal by microwave pavement maintenance vehicles.

Pothole repair is a commonly practiced pavement maintenance conducted by many state highway agencies. This study investigated the current practices of pothole repair and their cost-effectiveness. A nationwide questionnaire showed that the throw-and-go method is widely used because of its simplicity while semi-permanent technique is considered to be more cost-effective. The field survey showed that the throw-and-roll patches placed in the winter time deteriorated quickly in the first three months, whereas the patches that survived the first winter or that were repaired in the spring lasted much longer. Although semi-permanent repairs have a higher one-time repair cost due to increased equipment and labor cost, they were proved to be more cost-effective in a long term. The throw-and-roll applied in the spring season appeared to be the most cost-effective repair strategy, while including winter season throw-and-roll are less cost-effective. Avoiding patching in severe season and conducting preventive patching could potentially improve the cost-effectiveness.

Evaluation of subgrade soil stiffness provides valuable information about the expected behavior and response of pavements, which can be used to group pavement sections with similar structural capacities and pavement maintenance and rehabilitation to prioritize projects. A deflection test, such as the falling weight deflectometer (FWD), is commonly used to determine subgrade resilient modulus (MR) from its measured deflection data. A correction factor has been applied to the American Association of State Highway and Transportation Officials (AASHTO) MR equation for adjusting the difference between laboratory MR and the in situ measurements (with the FWD). However, large variations on the correction factor result in less accuracy of subgrade MR based on FWD measurements. The objective of this research is to evaluate the accuracy of the AASHTO MR equation and improve its accuracy by adjusting the MR correction factor. This paper consists of subtasks: (a) evaluating the current AASHTO MR correction factor; (b) evaluating the affecting factors (i.e., subgrade soil stiffness, bedrock depth, highway classification, and environmental condition); and (c) developing a framework to determine accurate MR correction factor.

Botswana roads largest assets estimated value as at 2010 was about 2 billion dollars. Out of the 18,300km Botswana Public Highway Networks, district gravel road networks are significant in providing access to rural areas where the majority of the population lives. District road managers need intelligent pavement management systems. Although much research has been devoted to performance modeling of pavements, a comprehensive model that could predict gravel loss condition accurately has yet to be developed in Botswana. Accurate prediction of gravel loss condition is important for efficient management of gravel road networks. Moreover, reduction of prediction error of gravel road performance models could conserve significant budget savings through timely interventions and accurate planning. This research developed gravel road performance models using Feed Forward Neural Networks (FFNN) modeling technique that is increasingly being used as alternative to traditional model-based technique to predict gravel loss (GVL) for the first time within a district in Botswana. The input data for the models were generated from the time series triennial condition survey for Botswana carried out in 2002, 2005 and 2008. The expected output, gravel loss (GVL) prediction using FFNN technique gave R 2 = 0.94 which outperformed the multiple regression technique of R 2 = 0.74 used to compare the models’ accuracy. The developed improved intelligent gravel road performance models will give district road maintenance managers information about the gravel loss conditions and equip them with the background needed for sustainable and efficient pavement maintenance interventions to keep the gravel road networks in a good condition in Botswana.

Pavement's structural evaluation that provides valuable information about the expected behavior and response can be used at the network level of pavement management to prioritize projects. A deflection measurement such as the falling weight deflectometer (FWD) can be used to identify problematic areas and group pavement sections with similar structural capacities. The structural condition index (SCI), a ratio of the existing structural number (SNeff) and the required SN (SNreq), is a screening tool for the pavement network-level management. For the successful implementation of the SCI concept at the network level, one critical issue is the accuracy of the index in evaluating the structural and deterioration conditions of the pavements. A field visit illustrates that the current SCI analysis underestimates the existing structural condition and results in overestimated treatments in pavement maintenance and rehabilitation. This paper presents and discusses how to improve the current SCI algorithm, mainly enhancing the estimation of the SNreq.