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Although pavement maintenance and rehabilitation (M&R) techniques are usually examined in economic terms, there is a growing need to address their environmental footprints. The objective of this study is to assess the environmental impacts of M&R techniques. Life cycle assessment (LCA) can help in the decision-making process of selecting suitable maintenance techniques based on their environmental impacts. This study investigates: patching, rout & sealing, hot in-place recycling, and cold in-place recycling. Global warming potential (GWP), acidification potential, human health particulate, eutrophication potential, ozone depletion potential, and smog potential are estimated as environmental impacts for each maintenance activity. Materials, equipment use (for construction and M&R), and transportation were the main elements considered. A sensitivity test is performed to identify the significant factors for the LCA. The study concluded that GWP was the most important impact category. Rout & sealing and cold in-place recycling produced the lowest GWP emissions. Notably, pavement patching and hot in-place recycling showed significant detrimental environmental impacts.

Road and pavement maintenance affect directly traffic safety and comfort. At the same time, maintenance treatments cause traffic discomfort and absorb valuable resources, thus, the choice of maintenance and rehabilitation technique is a complex, yet crucial issue. Road operators need to seek for the financial prerequisites for the success of maintenance strategy. Subsequently, the expected economic benefits will be inextricably linked to road performance features. The study herewith presented enlightens the economic aspect of mainly used pavement maintenance techniques, so as road operators identify the preferred one as regards budget needs. A comprehensive method to evaluate the current maintenance and strengthening techniques for flexible pavements using economic assessment tools is the main task of this paper. The results are meant to be a useful tool for road operators to conclude to the preferable, in terms of financial needs, alternative for maintenance and strengthening works.

The choice between continuously reinforced concrete pavement(CRCP) and jointed concrete pavement(JCP) for different concrete pavement applications has long been controversial. Research on these two...

In this study, an optimization model for road maintenance scheduling is proposed. The proposed model determines a maintenance schedule for a given set of links in an urban road network, that minimizes the total travel time during the maintenance period under a set of assumptions and a particular crew number constraint. It is assumed that all lanes of a road to be repaired are closed to traffic during the maintenance. Ant Colony Optimization (ACO), a suitable algorithm for discrete transportation problems, is employed in the proposed model. The model generates a set of roads to be closed for each maintenance day. The total travel time during the whole maintenance period is calculated using the deterministic user equilibrium assignment model. The proposed model is applied to a test network, and more efficient schedules in terms of total travel time are obtained compared to randomly generated schedules.

This Special Issue “Sustainable Designed Pavement Materials” has been proposed and organized as a means to present recent developments in the field of environmentally-friendly designed pavement materials. For this reason, articles included in this special issue relate to different aspects of pavement materials, from industry solid waste recycling to pavement materials recycling, from pavement materials modification to asphalt performance characterization, from pavement defect detection to pavement maintenance, and from asphalt pavement to cement concrete pavement, as highlighted in this editorial.

To improve microwave heating efficiency of asphalt pavement, a new technique was proposed by coating a very thin layer of magnetic Fe3O4 films on coarse and fine aggregates, using chemical co-preci...

This paper proposes an Analytic Hierarchical Process (AHP) theory based method to determine the weight of the decision-making influence factors, considering their relative significance and generating an overall ranking for each road section. A case study on the highway network maintenance priority was conducted to illustrate the proposed procedure. A total of five pavement maintenance decision-making related factors were considered in the study, including pavement performance, pavement structure strength, traffic loads, pavement age and road grade. The weightings of the five factors were quantified through AHP method. Then, the comprehensive ranking index value Ui was determined, which indicated the maintenance priority of a road section in network level decision-making. From the aspect of maintenance cost, the sensitivity analysis results were in accordance with the weightings of different maintenance decision-making factors. The pavement maintenance cost was significantly sensitive to the change of pavement performance. The case study clearly demonstrated the applicability and rationality of the AHP theory based decision-making method and it can be used as a guideline for pavement maintenance agencies. Keywords: Asphalt pavement, Network level, Maintenance decision-making, Analytic Hierarchical Process, Factor weight, Priority

The automatic pavement management system has the advantage of providing reliable pavement maintenance and rehabilitation strategies aiming at prolonging existing pavement service life. Therefore, t...

Many transportation agencies lack sufficient funds to maintain and repair roads, which results into increased pavement maintenance cost. Pavement Management System (PMS) has demonstrated to be an essential tool for proper management of infrastructure and proper utilization of available funds. The University of Tennessee at Chattanooga utilized Micropaver software as PMS tool to conduct a pavement management analysis of principal arterials in the City of Chattanooga. The study used the City of Chattanooga pavement database to create the current and future pavement conditions. Maintenance and repair (M&R) planning analysis was also performed in order to determine the most cost-effective treatment and suggest the optimum utilization of funds for the city. An analysis of five budget scenarios was conducted for a five-year plan using the critical pavement condition index (PCI) method (ASTM D6433). Results show that the backlog elimination budget would be the best scenario because it increases the pavement condition and eliminates the backlog of major maintenance and repairs over the five-year period. The unlimited budget seems though ideal, it does not improve pavement condition. Maintaining current condition and limited budget scenarios would increase both the backlog and the total cost of maintenance and repairs over the analysis period.

A significant number of agencies allocate low funding levels for their low-volume roads (LVRs) as part of their pavement management system (PMS) funding strategies. Although agencies have been appl...

The correct and timely assessment of the airport pavements surface quality is fundamental to verify the presence of any irregularities that could be detrimental to aircraft operations. Furthermore, a rough runway can increase the maintenance costs of both pavements and aircrafts landing gears, due to the increment of dynamic loads and fatigue phenomena on airplanes structural elements, reducing their service life. Nowadays, the maintenance budget available by airport agencies is very restricted, thus, it is necessary to define properly the type and the extension of interventions able to restore runway evenness. In this paper, the roughness assessment of real runway profiles is carried out using first of all BBI and IRI but also ProFAA simulation model, with particular attention to Cockpit Vertical Accelerations, underling the different impact on airport pavement management of the results provided by them. In particular, very low correlations for the whole sample of examined profiles were found bet...

Purpose This research aims to use the finite element method to examine critical distress modes in the pavement layers due to changes in the structural properties brought upon by fire damage. Design/methodology/approach A full dynamic analysis is performed to replicate heavy vehicle axle wheel loads travelling over a pavement section. Findings Results show a 72 per cent decrease in the number of load repetitions which a fire-damaged pavement can experience before fatigue cracking of the asphalt. Further, there is a 51 per cent decrease in loading cycles of the subgrade before rutting of the fire-damaged system. Originality/value Fatigue of asphalt and deformation of subgrade from repeated vehicular loading are the most common failure mechanisms, and major attributors to pavement maintenance and rehabilitation costs. Pavement analysis has always been concentrated on evaluating deterioration under regularly occurring operational conditions. However, the impact of one-off events, such as vehicle petroleum fires, has not been evaluated for the effects on deterioration.

The most important issue in managing low-volume roads (LVRs) is to define standards and practices applied on roads. In recent years, transportation agencies have dealt with considerable challenges ...

The aim of the studyis to develop Pavement Maintenance Management System (PMMS) for four roadsections of urban road network (Patiala, Punjab, India) using HighwayDevelopment and Management (HDM-4) model. The HDM-4 provides a deterministicapproach in data input and process data of existing road condition, trafficvolume and pavement composition to predict road deterioration as per the urbanroad conditions in terms of International Roughness Index (IRI) value. Thisstudy presents the use of HDM-4 model for the computation of optimumMaintenance and Rehabilitation (M&R) strategy for each road section andcomparative study of scheduled and condition responsive M&R strategies. Theresults of present study will be useful for gaining better support for decision-makersfor adequate and timely fund allocations for preservation of the urban roadnetwork.

The Highway Development and Management 4 (HDM-4) model was developed by the World Bank and used for pavements management system. An approach of the adaptation to local conditions is therefore required by adjusting the calibration factors, with the consideration of the context in which they are to be applied. The aim of the present work is to suggest these calibration factors for predicting the deterioration (structural cracking, ravelling, potholes and their resultant roughness) of roads in Morocco. The careful choice of such maintenance work planning is based on the result of these models. This study is based on the exploitation of road database, obtained from visual inspections and measurements performed by the National Center of Road Study and Research. The monitoring covered 6 years and concerned 55 test sections located on the Moroccan territory. Four kinds of structures were analysed involving different pavement bodies, constituting materials and thicknesses. The used method is based on a statistica...

The application of Analytic Hierarchy Process (AHP) method for the prioritization of pavement maintenance sections is widespread now-a-days. Although the evaluation of pavement maintenance section through AHP method is simple, where the relative importance (on Saaty’s scale) assigned to each parameter in the hierarchy varies between the experts (transportation professionals) consulted, which leads to discrepancies in the final rankings of the sections’, due to the subjectivity in the process. Further, experts base their decisions solely on their experience while consideration is not given to the actual quantitative physical condition of the roads. To overcome these difficulties an objective based AHP method is proposed in this study, where pairwise comparison values are assigned based on the collected field data from a road network in Mumbai city, consisting of 28 road sections. The final ranking list of candidate sections takes into consideration the priority weight of alternatives, which reflect the road conditions. The solution of priority ratings of AHP method is compared with the corresponding solution of road condition index method, a traditional pavement maintenance procedure. The findings of the present study suggest that objective based AHP method is more suitable for the prioritization of pavement maintenance of roads. Keywords: Prioritization, Analytic Hierarchy Process, Road condition index, Objective method, Rating and ranking

In this study, the effect of the pavement maintenance cycle on the fatigue reliability of simply-supported steel I-girder bridges under dynamic vehicle loading is studied. The bridge model and the fatigue load model are both adopted from the Load and Resistance Factor Design (LRFD) Bridge Design Specifications of the American Association of State Highways and Transportation Officials (AASHTO). A three-dimensional vehicle-bridge coupled model is developed to simulate the vehicle-bridge interaction and used to obtain the stress ranges of the steel bridge girders under the dynamic vehicle loading. Numerical simulations are carried out to study the influence of three important parameters, including the road surface condition, bridge span length and vehicle speed, on the fatigue damage induced by the fatigue truck. The results from this study show that the bridge fatigue reliability decreases dramatically under repeated dynamic vehicle loads when the road surface condition is very poor and that the pavement maintenance cycle has a significant influence on the bridge fatigue reliability. A procedure for determining the desired pavement maintenance cycle to achieve the target fatigue reliability of steel bridge girders is developed. An example is also provided for demonstrating the proposed procedure.

The Moving Ahead for Progress in the 21st Century Act highlighted the need to monitor the performance of pavement sections over time. An important aspect of performance monitoring is collecting a statistically significant sample of the network so conclusions can be made about changes in performance and types of maintenance and rehabilitation needed for maintaining these assets. This paper reviews the sampling requirements on the Interstate highway system to draw accurate conclusions about the network. Specifically, the paper answers the following questions: Is two-way data collection necessary? Do data have to be collected in more than one lane in a direction? What is the optimum reporting length? For what percentage of the network should data be collected? Should data be collected annually?

Crack sealing (CS) and crack filling (CF) are commonly used crack treatment methods. However, the study of their performance is still very limited, making it difficult for highway agencies to systematically and optimally select network-level CS-CF projects within available budgets. To address this issue, a generalized performance model for CS-CF–treated pavements is proposed. Detailed crack characteristics—including crack type, density, and width—are employed in the model. In the proposed performance model, crack density related to three types of cracks (transverse cracks, nonwheelpath longitudinal cracks, and wheelpath longitudinal cracks) is used to determine performance gain. Two discount functions are incorporated to consider the negative impact caused by alligator cracks and cracks that are very tight or very wide. The proposed model is instantiated and estimated using the practices of the Georgia Department of Transportation on CS and CF and the department’s pavement distress survey protocol. The case study—which uses three-dimensional laser data collected from a 1-mi pavement section on State Route 26 (US-80) near Savannah, Georgia, from 2011 to 2016—validates the feasibility and reasonableness of the model. An integer programming method is formulated for network-level CS-CF project selection. The testing results of 53 pavement segments show that the model and programming method can be used to select CS-CF projects within budget constraints while maximizing the length-weighted average performance gain. The proposed performance model and integer programming method show promise for use in incorporating CS and CF into a highway agency’s pavement management system. Conclusions and recommendations are offered.

Driver fatigue and drowsiness can have a profound impact on safety. Centerline and shoulder rumble strips are popular countermeasures designed to produce audible and tactile warning when vehicles deviate from the travel lane onto the rumble strips. These warnings reduce the risk of lane departure crashes. Studies show that the noise produced by rumble strips is a function of many variables. Rumble strip depth is known to have the greatest impact in alerting drivers. However, chip seal pavement maintenance operations tend to reduce the original rumble strip design depth, which may have an impact on the functional effectiveness of the rumble strips. The purpose of this study was to conduct a controlled experiment to understand the relationship between milled rumble strip depth and noise and vibration in the vehicle cab. In-vehicle noise and vibration levels were collected on rumble strips of five depths (⅛, ¼, ⅜, ½, and ⅝ in.) and three types (shoulder, single centerline, and double centerline) on three highways in the state of Nebraska by two vehicles traveling at speeds of 45, 55, and 65 mph. Rumble strip depths at ⅛-in. intervals were used to simulate the influence of a chip seal on rumble strip effectiveness. From the in-vehicle sound and vibration levels of all the tested rumble strip depths, it can be hypothesized that a ⅛-in. reduction in the current milled rumble strip design depth, as a result of chip sealing, would not cause a practical reduction in the effectiveness of rumble strips producing audible and tactile warnings to alert drivers.

Maintaining a sufficiently short stopping distance is an important requirement for safe road operation. Stopping sight distances of road sections are decided during the highway alignment and roadway geometric design phase of the road development process. A pavement friction coefficient is used in the calculation of the stopping distances. Since pavement friction coefficient deteriorates with time under traffic action, and the available friction also reduces in wet weather, it is important for pavement maintenance engineers to ensure that sufficient skid resistance is maintained under actual operating conditions so that the stopping distances of road sections are less than the required safe stopping distance. This result requires pavement engineers to monitor regularly the available pavement skid resistance and the corresponding stopping distance of individual road sections. Because skid resistance is an accepted pavement condition to be measured in a pavement management system, it is proposed in this study that braking distance assessment be included as a part of the pavement condition monitoring program of a pavement management system. The proposed procedure consists of two parts: ( a) measurement of skid resistance and evaluation of braking distance and stopping distance and ( b) monitoring of the deterioration trends of individual road sections. The detailed procedure and the analytical tools necessary for the evaluation and prediction of braking and stopping distances, including a finite element skid resistance simulation model, are presented. A numerical example is presented to illustrate the concept and working of the proposed procedure.

Chip seals are applied to existing roadways to slow deterioration and improve pavement surface conditions without increasing the pavement’s structural capacity. The raveling of chip seals can cause damage to vehicles and thus is a safety concern. Raveling resistance is related to both material application rates and material properties. The current chip seal specifications fail to adequately address the material-related aspects of raveling resistance. This study seeks to develop recommendations to address raveling resistance in future chip seal specifications. Strain sweep binder tests, binder bond strength (BBS) tests, and Vialit chip seal mixture tests were conducted to assess early raveling, late raveling, and wet raveling at two intermediate temperatures. The results demonstrate that the bond that develops between the residual binder and the aggregate is highly dependent on the interaction between the emulsion and the aggregate during curing. The importance of emulsion–aggregate compatibility in raveling resistance indicates that raveling resistance cannot be addressed in binder specifications alone. Rather, it is recommended that intermediate temperature raveling resistance should be addressed during chip seal mixture design. Vialit and BBS tests, in which emulsion is cured on rock, can both be used to effectively quantify the aggregate loss potential of a chip seal. These two tests are able to capture the benefits of polymer modification and produce results that correlate. However, the Vialit tests are easier to implement than the BBS tests and require no expensive equipment. Therefore, Vialit tests are recommended to address early, late, and wet raveling resistance in future chip seal specifications.

A project candidate selection and ranking model (PCSRM) is commonly applied in pavement maintenance and rehabilitation planning. Typically, these models use empirical mathematical expressions that do not have a clear physical meaning and cannot accurately assess the priority of transportation agencies or pavement engineers. To overcome this limitation, this study developed a method, based on the analytical hierarchy process (AHP), to identify pavement-related factors and improve the accuracy of the PCSRMs currently used by the Austin District (Texas Department of Transportation) in its 4-year plan. The aim was to identify pavement-related factors that reflected the engineering judgment of transportation agencies and pavement engineers. The proposed method had three major components: AHP design, AHP survey and results analysis, and factors selection. A three-tier hierarchy structure of one objective, five goals, and 18 alternatives was defined. Additionally, a system to check for consistency was developed on the basis of literature recommendations. An Excel-based survey tool was developed with the objective of providing a relatively easy visual interface for the participants. The design and development of the survey tool were carried out in collaboration with the district pavement preservation engineer. Seventeen Texas Department of Transportation pavement experts completed the AHP survey with the required consistency ratio. Clustering analysis was performed to identify the pavement-related factors that showed the highest priorities. The factors with the highest overall weights should be considered in future PCSRM improvement.

The paper presents comparative characteristics of the main types of profilometers used for measuring of longitudinal roughness of the road surface. Certain issues related to accuracy of road roughness measurement with profilometers are considered.

This paper focuses on solving the problem of budget allocation for the pavement maintenance management of an urban road network. To do this, a decision-making tool is developed. The tool is based on a quantitative valuation of six sustainable criteria to obtain a priority ranking. The relative weights are calibrated with the aim of obtaining a higher benefit-cost ratio to a horizon of 4 years. The tool is applied to a sample of Valencia's urban road network. The work concludes that decision-making based on sustainable criteria increases the ratio benefit-cost in 53%, compared with the plan based only on the condition of the pavement, which is typical in management agencies lacking an assessment tool. The application of the tool to an urban road network that differs in conditions with the sample analyzed must be preceded by a calibration similar to the one raised, in order to define the optimal scenario in relative weights.

Each road authority requires set maintenance standards and strategies to manage its roads. This paper has achieved that for the Queensland road authority as an example. The 34,000 km road network has been divided in to 27 road groups using pavement type, loading and pavement strength as criteria to set standards and strategies for each of them, which helps managing different classes of roads efficiently. The HDM-4’s road deterioration and work effects models with ‘minimize agency cost and maximize performance’ optimisation algorithm are used to obtain an optimum solution from 36 alternatives for a road group. The results provided ideal standards, necessary cost-effective treatments and an optimum budget for sub groups and ultimately to the whole network. It is observed that about $17.8bn is needed to maintain the flexible and composite roads in the next 20 years at 4.0 International Roughness Index (IRI in m/km). Some key findings on pavement life cycle performances and budget are also discussed.

In Taiwan, both the engineers and temporary employees serving in National Freeway Bureau are graduates of civil engineering. The lack of specialization in the pavement domains as students and the increasing financial requirement of pavement maintenance are hindering new engineers from further improving their knowledge on pavement. The present study aimed to improve the comfort index of national freeways. First, the inspection aspects of national freeways, such as road testing items and methods, are analyzed. Subsequently, the lack of previous literature on this subject prompted the researchers to organize relevant information pertaining to the comfort index and inspection processes of national freeways. The inspection and analysis of national freeways are beneficial for maintaining and enhancing the comfort and quality of national freeways. Moreover, the International Roughness Index is adopted to elucidate the differences exhibited at different speeds. In addition, the present study endeavored to determine skid number (SN) degradation equations to improve road traffic safety. First, a correlation analysis between SN and traffic flow, as well as between SN and climate data, was performed. Findings revealed an increased correlation between SN and traffic flow, while the correlation between SN and climate (temperature and rainfall) is less prevalent. Subsequently, traffic flow and climate were adopted as the factors for the SN degradation equations. The present study divided the traffic flow data of the entire national freeway system into five groups, enabling researchers to present individual SN degradation equations for various traffic flow conditions, thereby contributing to maintain and elevate the road traffic safety of national freeways.

Millings or old pavement materials (also known as reclaimed asphalt pavement) are used in pavement base and surface course mostly for rehab and reconstruction processes. Millings can also be used in pavement maintenance such as chip seal. However, it is not known whether chip seal with millings are cheaper than chip seal with virgin chips considering their lifetime performance. In this study, life cycle cost of chip seal with and without millings was determined from data gathered by surveying three transportation Districts in New Mexico. Performance plot over time was used to evaluate the benefit and cost-effectiveness index (EI). For all districts, chip seal with millings has higher EI compared to chip seal with virgin aggregates.

This study assesses the effectiveness of road network pavement maintenance using Markov Chain analysis based on historical costs and road roughness progression data. The analysis is based on a database developed by the State of Victoria, Australia, consisting of 2197 road sections. The analysis measures maintenance effectiveness using the criterion of whether road sections remain in the same condition state or move to the next worst state based on a predefined roughness value. Principal inputs for the stochastic models, such as the development of transition probability matrices and associated cost functions, are discussed. Results show that, within the current budget envelope and when undertaking only routine maintenance, the probability of road sections remaining in the same condition state, which is a determinant of maintenance effectiveness, exhibits a declining tendency from good to worst condition states. This finding prompts the discussion on when to begin intervention using high types of ma...

National Road Network which consists of a traditional road structure and modern roads, require planned maintenance and should be in accordance with the needs. The limited choice of available national road network and the deviation of the overloading encourage the government to be more responsive to carry out maintenance management. The institution in charge of road maintenance is often constrained by the limited budget available. A two-objective optimization model considers maximum roughness and minimum maintenance cost for used road network with overload. The study was conducted on the entire national road network in West Java which are paved with flexible pavement. In the proposed approach, data mining model are used for predicting the roughness index over a given period of time. Routine and periodic maintenance are chosen in this study. Multi-objective optimization model was developed based on Genetic Algorithms. Budget constraints and overloading are the two constraints in the developed model. Based on the R-Tools result, the Pareto optimal solutions of the two objective functions are obtained. From the optimal solutions represented by roughness index and cost, an agency more easily obtain the information of the maintenance planning. Results of the developed model has been implemented through the selection of maintenance on the road network scenarios with different levels of overload.

Potholes are one of the key defects that affect the performance of roads and highway networks. Metrological features of a pothole provide useful metrics for road distress measurement and severity analysis. This paper presents a performance analysis of Kinect as a sensor for pothole imaging and metrology. Depth images of paved surfaces are collected from concrete and asphalt roads using this sensor. Three-dimensional (3D) meshes are generated for a variety of pothole configurations in order to visualise and to calculate their different metrological features. The sensor is benchmarked using a test-rig with pothole-like depressions or artificial potholes of known dimensions to evaluate sensor performance under different real-life imaging conditions, such as through the media of clear, muddy and oily water. Error in measurement due to surface roughness is also studied. Another source of error that is due to the presence of foreign objects such as stones and pebbles in the form of negative depth, is al...

Comfort is a major requirement in planning pedestrian facilities. Pedestrians walk where they feel comfortable and when they do not feel at ease, they walk elsewhere. A typical example is that filthy, distressed, or too narrow sidewalks induce pedestrians to walk on carriageways. This behaviour jeopardizes road safety and highly dangerous to most users, leave them vulnerable. Unsuitable pavements can be the result of irregular maintenance operations to restore evenness after shock damage, weather phenomena, installation of equipment (e.g., posts, fences, urban furniture) with a reduction of walkable surface, or substandard repair work on pavements and patches due to emergency operations. These problems can be solved with an appropriate maintenance management system, which optimizes financial resources to make smart decisions about how to intervene with an adequate and lasting maintenance operation. This paper defines an evaluation index for sidewalk conditions as a part of an efficient set-up of a Sidewalk Management System, which is similar to the better known Road Management System. The study relies on surveys, as well as the classification and analysis of sidewalk distresses. The authors adapted an index already standardized by ASTM for roads and airports: the Pavement Condition Index (PCI). PCI has been modified to consider the specific types on the sidewalks studied within this paper. To validate the method, a case study of a residential district in Rome, Italy, was carried out. The chosen area lacks regular maintenance and has therefore resulted in a network of unsafe sidewalks. Frequent detour routes were surveyed and related to the level of distresses within a general assessment of safety. This study concentrates on sidewalks with flexible pavements because this type of pavement is the only one adopted in the survey areas and, in general, throughout Italy.

Two empirical Markovian-based models are presented in this paper to predict the transition probabilities associated with rehabilitated pavement. The first model predicts the staged-homogenous transition probabilities as required by the staged-homogenous Markov model. The second model predicts the non-homogenous transition probabilities as applicable to the non-homogenous Markov model. In both the models, the deterioration transition probabilities are predicted as a function of the corresponding values associated with original pavement and two adjustment factors reflecting the impacts of increased traffic load applications and decreased pavement strength. The predicted transition probabilities are used to estimate the future distress ratings required for developing the corresponding life cycle performance curve. The life cycle performance/cost ratio is used to evaluate the cost-effectiveness of potential long-term M&R plans. The life cycle performance is defined as the area falling under the life c...

An accurate and reliable pavement crack detection system plays an important role in evaluating pavement condition and providing needed information for decision making for pavement maintenance and rehabilitation. Among existing crack detection methods, the seed-based image segmentation method has proved to be fast and efficient for automated crack detection. However, its performance is not stable under varying conditions. This paper proposes an extended and optimized seed-based crack detection method after an extensive review of current practices. The proposed method included two main steps. In the first step, pavement images were preprocessed. Lane marking was masked to be a noncrack area and the nonuniform background of the images was corrected. In the second step, crack seeds were detected through grid cell analysis and then connected through a Euclidean minimum spanning tree construction. In addition, undesirable small objects, such as minimal branches and noises, were removed by a path length–based removal method. The proposed algorithm was evaluated by using 105 pavement images collected with the Texas Department of Transportation VCrack system. The experiment results showed that the proposed method could accurately and efficiently detect cracks in the images.

This paper describes the development of a practical tool for selecting and prioritizing rehabilitation (RH) and preventive maintenance (PM) activities in roadway pavements. The development was based on data collected through a survey of district engineers of the Texas Department of Transportation (DOT). The survey collected data on the key factors used for selecting the projects to be treated and for deciding on RH versus PM treatments: pavement condition and distress scores, average daily traffic, surface age, ride score, and past PM expenditures. Weight factors were developed for each key factor by fitting simple logit curves to data obtained by surveying the 25 Texas DOT districts. These weights were aggregated into a prioritization score for PM treatment and another for RH treatments. This process was implemented into an Excel-based tool. The output of this tool was successfully compared with actual district decisions on the type of treatment applied and the priority assigned to pools of projects.

The objective of this study was to determine whether asphalt rubber (AR) binders will provide similar or better performance compared with a polymer modified asphalt (PMA) binder when used in a high-performance, ultra-thin lift overlay pavement preservation strategy. Current specifications for these types of overlays normally require the use of a PMA binder, because it has the ability to make these overlays more elastic under traffic loading and is less sensitive to temperature fluctuations. However, several state agencies are looking into the feasibility of incorporating sustainable and environmentally friendly technologies, such as AR binders and warm mix asphalt (WMA) technologies, into their asphalt mixtures, including those used for high-performance, ultra-thin lift overlays. This study examined the effect of binder modification type (AR or PMA) and the influence of the use of WMA in high-performance, ultra-thin lift overlays. In general, the mixtures that were tested provided comparable rutting, moisture damage, and low-temperature cracking performance in the high-performance, ultra-thin lift overlay. However, the use of the AR binders indicated reduced performance compared with the PMA binder in mixture fatigue cracking via the beam fatigue test, and mixture reflective cracking in the overlay tester. The results from the beam fatigue test were not always supported by the fatigue life predictions from the simplified viscoelastic continuum damage model. The only detriment to mixture performance for mixtures incorporating WMA was a reduction in fatigue cracking performance when used with AR binders.

Errors in pavement condition data can affect not only the assessment of current and predicted performance of the network but also the quality of pavement maintenance and rehabilitation plans. The large size of pavement condition databases makes manual error detection methods difficult to implement. This paper provides a new computational technique for detecting errors in network-level pavement condition data sets. The technique integrates conventional statistical methods and heuristics. The statistical methods are used to identify outliers in uniform performance families, and the heuristics are used for delineating potential errors from extreme, yet valid, behavior within these outliers. The new technique was validated with field data from Texas on pavement cracking. Of 9,166 audited pavement sections, 681 sections having potentially erroneous cracking data were detected. These potential errors are randomly distributed across the Texas roadway network and are not related to a specific geographic region, district, or climatic zone. Pavement engineers can use the presented technique to identify potential errors in large pavement condition data sets and to design more effective programs that ensure the quality of these data.

Recent military operations have highlighted the need for new expedient pavement repair capabilities to improve current guidance on airfield damage repair. Damaged or distressed military airfield pavements must be repaired with expedient methods and durable materials to minimize the time the pavement is removed from service and to reduce or eliminate additional closure times for subsequent repairs. Extensive research was conducted to develop several airfield pavement repair techniques that could be applied across the full spectrum of military airfield repair operations. This paper focuses on the research conducted to develop a new foam backfill technology for airfield pavement repairs. Results of initial laboratory and field tests showed that rigid, poured polyurethane foam is the most applicable backfill solution for deployed locations because of its ability to expand to several times its shipped liquid volume when mixed, reducing the logistical burden of transporting aggregate backfill materials. This paper describes laboratory and field experiments that used foam backfill and prototype equipment to develop a pavement repair technique that supports threshold and objective aircraft pass levels defined for expedient airfield repairs. The research included laboratory testing, full-scale field testing, and simulated and actual aircraft traffic tests with C-17 and F-15 aircraft. Results of these tests validated and certified the foam backfill repair technique for military aircraft use. However, these experiments also identified material and equipment limitations that will require additional research before the repair technique is adopted by military repair teams. Conclusions and recommendations for future equipment and material improvements are provided.

Cold Recycling Technology (CRT) of worn out bituminous pavement is a relatively new technology which has important application in the road surface treatment and paving towards green highway. Due to economic and environmental constraints like reduction in construction cost, preservation of aggregate and binder, etc, more attention is turning towards recycling of bituminous surface as an alternative to conventional pavement rehabilitation. The objective of this paper is to analyze flexible pavement with insitu cold recycling technique using Reclaimed Asphalt Pavement Material (RAP) and Foam Bitumen. As a case study, pilot project consisting of segregated stretches having major distresses and totaling 10 km length were selected on Vadodara Halol Road Project (SH 87) where cold recycling technique using reclaimed material and foam bitumen was used as a part of rehabilitation of flexible pavement instead of conventional overlay in order to achieve economy and executing within limited time period. Various field as well as laboratory tests are conducted and representative cores were extracted to investigate the pavement characteristics. The results of tests conducted on the cold recycling surface are very encouraging and adopted CRT is found to be economically viable also.

Every year, millions of taxpayers’ dollars are spent maintaining roads. The money is used to repair damage that occurs to pavements, bridges, and other elements of the roadway system. The service life of a pavement can be greatly reduced by unexpected heavy loading, which is one consequence of hydraulic fracturing (fracking) activity in rural areas. This paper describes a tool that can potentially lengthen the service life of pavements, especially thin pavement structures, by predicting unusually heavy loading. Predicting activities that cause increased truck loading can help agencies plan preventive measures to reinforce pavement structures before they fail. The goal of this study was to develop a tool, an early warning system (EWS), that can help to predict locations where damage from heavy truck traffic will occur. Truck travel related to the oil and gas industry is predictable and has recently had significant effects on pavement deterioration. The study focused on well permitting activity in the Austin, Texas, Department of Transportation district. ArcGIS software was used to find route assignments by using trip origins and destinations for fracking activity, truck volume, and vehicle weights. Several road segments that would be at risk for heavy loading and shortened service life were successfully identified. This tool can provide information needed to prioritize proactive pavement maintenance for more effective use of tax dollars. This tool could potentially also be used to determine a roughly proportional cost of damage from fracking activity to be levied on the oil and gas industry, thus alleviating the burden on taxpayers.

Millions of dollars are annually spent for ice or snow removal from the roadways and airport paved surfaces in cold regions. The presence of snow or ice on paved areas can cause traffic accidents and financial loss because of flight cancellations or delays. For mitigating winter pavement maintenance issues, the use of superhydrophobic (super-water-repellent) coating techniques is gaining attention as a smart and cost-effective alternative to traditional snow and ice removal practices. This study focuses on creating, characterizing, and evaluating innovative superhydrophobic coatings on asphalt concrete surfaces for ice- and snow-free flexible pavement applications. The layer-by-layer (LBL) method was used to create an asphalt concrete surface coating with polytetrafluoroethylene (PTFE) as a well-known super-ice- and super-water-repellent material. Superhydrophobicity and skid resistance of the coated asphalt concrete surface were characterized by the water contact angle, the work of adhesion, and the coefficient of friction at the microtexture level. These properties were evaluated for test variables including spray times and dosage rates of PTFE under a statistical design–based experimental test program. The measurement results indicate that uses of the LBL method for spray-depositing the PTFE particles and the microtribometer for measuring coefficient of friction at the microtexture level are promising methods for creating and characterizing superhydrophobic coatings on asphalt concrete. The results of statistical analyses indicate that the spray time and dosage of PTFE significantly affect the ability of a coated flexible pavement to be icephobic or superhydrophobic and skid resistant.