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Laboratory investigation of traffic effect on the long-term skid resistance of asphalt pavements
... The greater the tire pressure, the more serious the AP skid resistance decay, and tread wear will reduce the drainage and water storage capacity of the tread pattern, accelerating the rate of decay of the AP skid resistance [11] Vehicle load The greater the vehicle load, the faster and greater the rate of decay of the skid resistance of AP, and compared with the overload traffic applied in the middle and late stage of wear, the deterioration rate of the pavement dynamic friction coefficient is faster, and the final value of the friction coefficient is lower when heavy traffic is applied in the early stage [130,131] Volume of traffic The more vehicle traffic there is, the faster the AP is abraded and the faster the AP's skid resistance decays [130] Vehicle running time ...
... The greater the tire pressure, the more serious the AP skid resistance decay, and tread wear will reduce the drainage and water storage capacity of the tread pattern, accelerating the rate of decay of the AP skid resistance [11] Vehicle load The greater the vehicle load, the faster and greater the rate of decay of the skid resistance of AP, and compared with the overload traffic applied in the middle and late stage of wear, the deterioration rate of the pavement dynamic friction coefficient is faster, and the final value of the friction coefficient is lower when heavy traffic is applied in the early stage [130,131] Volume of traffic The more vehicle traffic there is, the faster the AP is abraded and the faster the AP's skid resistance decays [130] Vehicle running time ...
This study aims to gain an in-depth understanding of the research trends in the field of the long-term skid resistance (L-TSR) of asphalt pavement (AP). In this paper, the detection method, decay model, influence factors, and prediction model of the L-TSR of AP are summarized. This paper quantitatively analyzes the skid resistance mechanism of the pavement and elucidates the existing problems and future development directions of the L-TSR of AP. The research indicates that digital image methods and intelligent sensor detection methods are important methods for the skid resistance detection of AP in the future. The indoor test can provide detailed data of material properties and can effectively evaluate the performance of anti-sliding materials under different environmental conditions by simulating the actual road conditions. A quantitative analysis of the skid mechanism of AP can better reflect the actual contact characteristics of the pavement. The combined prediction model combining multiple single models can not only correct the shortcomings of a single model but also greatly improve the calculation accuracy. At present, the research on the L-TSR of AP is insufficient in the aspects of the tire–pavement interaction mechanism, evaluation index, decay model, and combined prediction model, which needs to be further studied from quantitative, time-varying, unified, and innovative aspects.
... It means friction numbers of this roadway decreased only 0.02 on avera experiencing 2.5 million more traffic polishing when comparing the friction numb accumulated traffic at the middle and right wheel path of this roadway. This pheno aligns well with other studies that did laboratory investigations of pavement frict der different levels of polishing cycles [43][44][45]. However, to obtain the friction d rate for a longer term, the proposed framework, as shown in Figure 13, only me friction numbers from roadway locations experiencing different levels of traffic po along pavement horizontal direction (e.g., middle, wheel path, and edge) without ing performing extensive laboratory testing to polishing pavement samples or lon field monitoring over time. ...
... It means friction numbers of this roadway decreased only 0.02 on average after experiencing 2.5 million more traffic polishing when comparing the friction numbers and accumulated traffic at the middle and right wheel path of this roadway. This phenomenon aligns well with other studies that did laboratory investigations of pavement friction under different levels of polishing cycles [43][44][45]. However, to obtain the friction decrease rate for a longer term, the proposed framework, as shown in Figure 13, only measured friction numbers from roadway locations experiencing different levels of traffic polishing along pavement horizontal direction (e.g., middle, wheel path, and edge) without requiring performing extensive laboratory testing to polishing pavement samples or long-term field monitoring over time. ...
Pavement texture and skid resistance are pivotal surface features of roadway to traffic safety, especially under wet weather. Engineering interventions should be scheduled periodically to restore these features as they deteriorate over time under traffic polishing. While many studies have investigated the effects of traffic polishing on pavement texture and skid resistance through laboratory experiments, the absence of real-world traffic and environmental factors in these studies may limit the generalization of their findings. This study addresses this research gap by conducting a comprehensive field study of pavement texture and skid resistance under traffic polishing in the real world. A total of thirty pairs of pavement texture and friction data were systematically collected from three distinct locations with different levels of traffic polishing (middle, right wheel path, and edge) along an asphalt pavement in Oklahoma, USA. Data acquisition utilized a laser imaging device to reconstruct 0.01 mm 3D images to characterize pavement texture and a Dynamic Friction Tester to evaluate pavement friction at different speeds. Twenty 3D areal parameters were calculated on whole images, macrotexture images, and microtexture images to investigate the effects of traffic polishing on pavement texture from different perspectives. Then, texture parameters and testing speeds were combined to develop friction prediction models via linear and nonlinear methodologies. The results indicate that Random Forest models with identified inputs achieved excellent performance for non-contact friction evaluation. Last, the friction decrease rate was discussed to estimate the timing of future maintenance to restore skid resistance. This study provides more insights into how engineers should plan maintenance to restore pavement texture and friction considering real-world traffic polishing.
... The evolution of vehicular flow has an impact on the increase in traffic loads and, added to environmental conditions such as temperature variation and precipitation, facilitate the premature development of failures in the structure of asphalt pavements [4,5]. Indeed, the factors associated with overloading are predominantly involved in the early phases of the pavement's life cycle [6]. ...
The useful life of pavements determines the design of asphalt mixtures. However, premature structural failures and low durability are one of the main problems in pavement engineering today. The action of loads produced by traffic, exposure to environmental factors and the inadequacy of conventional designs of asphalt pavements are some of the main problems associated with the durability of the pavement. The modification of asphalt binders is an alternative that has been used for some years to improve the properties of bituminous material. Among the modifying materials are elastomers, a class of polymers with elastic properties that can be heat-treated. In this study, the asphalt was modified by wet means by adding 5, 10 and 15% of Thermoplastic Polyurethane (TPU) by weight of the binder. Subsequently, standard samples were prepared with the characterized constituents and mixtures with the modified asphalt cement. Consequently, tests were carried out to obtain the optimal mixture that improves the properties of conventional pavement. The results show that the optimal TPU addition content is 5%. With this percentage, the modified binder presented a greater elastic recovery of up to 5.60% and a reduction of up to 42.6% in penetration compared to conventional asphalt. In addition, using the Marshall method, it was determined that the stability of the modified mixtures was much higher than that of standard mixtures for light, medium and heavy traffic; so, they will have a higher resistance to deformation and better fatigue behavior.
The performance of the pavement in terms of vehicle safety and tire wear is affected by the friction behavior of the pavement. To highlight the main characteristics that affect the production of better friction resistance of the pavement surface in this work. The micro-texture and macro-texture of the asphalt surface of Baghdad Airport highway were studied using two methods: (sand patch method and the British pendulum test). The sand patch was examined by drawing sand grains of a specific volume, while the micro-texture was analyzed using a BPT under dry and wet surface conditions. All data obtained from the two examinations were analyzed and modelled statistically using SPSS 25 software. Results show that skid resistance of pavement surface increase with the increase of MTD, this increase may be due to the increase of coarse aggregate which lead to increase the roughness of the pavement surface, this increase ranged between (96 - 91%). MTD decreases with the increase of traffic flow due to the friction between the road surface and the vehicle tires leading to increase of smoothness of the road surface. This is mean that MTD is highly affected by the traffic flow and this effectiveness ranged between (84-97%). Skid resistance also is highly affected by the traffic flow with an effectiveness ranged between (81-94%) for both pavement conditions. According to the regression analysis for friction and other parameters, it can be concluded that surface friction values are highly affected by cumulative traffic (asphalt mix deterioration) over time. Doi: 10.28991/cej-2021-03091775 Full Text: PDF
Skid resistance is a significant feature that provides consistent traffic safety management for road pavements. An appropriate level of Skid resistance describes the contribution that the pavement surface makes to tire/road friction, and the surface of the road pavement can reduce vehicle operation cost, traffic accidents, and fatalities, particularly in wet conditions. Wet conditions decrease the level of the skid resistance (pavement friction), and this may lead to serious struggles related to driving on the road pavement (e.g., skidding or hydroplaning), which contributes to higher crash rates. The knowledge of skid resistance is essential to ensure reliable traffic management in transportation systems. Thus, a suitable methodology of skid resistance measurement and the understanding of the characterization of the road pavement are key to allow safe driving conditions. This paper presents a critical review on the current state of the art of the research conducted on skid resistance measurement techniques, taking into account field-based and laboratory-based methodologies, and novel road sensors with regard to various practices of skid resistance, factors influencing the skid resistance, the concept of the minimum skid resistance and thresholds. In conclusion , new trends that are relevant to data collection approaches and innovative procedures to further describe the data treatment are discussed to achieve better understanding, more accurate data interoperability, and proper measurement of skid resistance.
Texture is required on road pavements for safe vehicle braking and manoeuvres. This paper provides a unique analysis of long-term texture obtained using traffic speed condition survey (TRACS) data from 14 sites, located along a north to south transect spanning the longest highway in the UK. A total of 19 years of sensor measured texture depth (SMTD) data have been analyzed using spatial filtering techniques and compared with meteorological and traffic datasets. The results for hot rolled asphalt (HRA) surfaces reveal that changes to SMTD follow a linearly increasing trend with time. The “rate of change” is influenced by the order of magnitude of annual average daily traffic (AADT), when factored for the percentage of heavy goods vehicles. This linear trend is disrupted by environmental parameters, such as rainfall events and seasonal conditioning. In the summer, this signal is evident as a transient peak in the “rate of change” of texture greater than 0.04 mm, and in the winter as a reduction. The transient changes in texture corresponded to above average rainfall occurring in the week prior to SMTD measurement. The signal observed demonstrates an inverse pattern to the classically understood seasonal variation of skid resistance in the UK, where values are low in the summer and high in the winter. The findings demonstrate for the first time that texture measurements experience a seasonal signal, and provide compelling evidence pointing toward surface processes (such as polishing and the wetting and drying of surface contaminants) causing changes to texture that are affecting seasonal variation in skid resistance.
Proper tire–pavement interaction is essential for the safety of motorists. Pavement surface texture is a major contributing factor to tire–pavement friction. This study performed a series of statistical analyses of field-measured friction and texture data to find the texture–friction correlation. Three test sections with different pavement types were selected within the state of Texas. Data were collected at three locations in the right wheel path and three locations in the center of the lane for each test section. To measure the texture data, the researchers used the circular track meter (CTM) and a prototype measurement device developed in-house and consisting of a line laser scanner (LLS). Friction measurements were obtained with the dynamic friction tester (DFT) and Grip-Tester. The mean profile depth (MPD) was calculated by using the measured texture data. The relationship between the MPD values and the friction numbers obtained from the Grip-Tester and DFT was investigated at speeds of 50 and 70 km/h (31.1 and 43.5 mph). The repeatability and reliability of both the developed LLS prototype and the Grip-Tester were also evaluated, as well as the effect of test speed on friction measurement. The results indicated a strong positive correlation between the texture and friction data. In addition, the developed LLS prototype was able to scan the pavement surface texture more reliably and precisely than the CTM in terms of vertical and horizontal resolution. The Grip-Tester showed promising results compared with the DFT with regards to the friction measurement.
The skid-resisting performance of pavement is a critical factor in traffic safety. Recent studies primarily analyze this behavior by examining the macro or micro texture of the pavement. It is inevitable that skid-resistance declines with time because the texture of pavement deteriorates throughout its service life. The primary objective of this paper is to evaluate the use of different asphalt pavements, varying in resilience, to optimize braking performance on pavement. Based on the systematic dynamics of tire-pavement contact, and analysis of the tire-road coupled friction mechanism and the effect of enlarging the tire-pavement contact area, road skid resistance was investigated by altering the elastic modulus of asphalt pavement. First, this research constructed the kinetic contact model to simulate tire-pavement friction. Next, the following aspects of contact behaviors were studied when braking: tread deformation in the tangential pavement interface, actual tire-pavement contact in the course, and the frictional braking force transmitted from the pavement to the tires. It was observed that with improvements in pavement elasticity, the actual tire-pavement contact area increased, which gives us the ability to effectively strengthen the frictional adhesion of the tire to the pavement. It should not be overlooked that the improvement in skid resistance was caused by an increase in pavement elasticity. This research approach provides a theoretical basis and design reference for the anti-skid research of asphalt pavements.
Skid resistance of road surfaces is an important safety parameter. Decreasing skid resistance correlates with increasing number of accidents. The presented study aims for a correlation between lab-based polishing simulation and skid resistance measurement and evolution of the skid resistance under traffic in the field. A prediction model for skid and polishing resistance based on the Wehner/Schulze device was developed. The lab procedure as a basis for the model works on the hypothesis that a maximum level of skid resistance exists that can be regenerated even from a highly polished state by sandblasting of the surface. This hypothesis was verified for an asphalt and concrete surface material. The prediction model was set up by correlating field data on skid resistance and traffic volume from 14 test sections to cores taken from these test sections and tested in the lab. A linear regression links the cumulated traffic volume in the field with the number of polishing passes in the Wehner/Schulze device. Thus, it is possible to simulate millions of wheel passes within a couple of hours in the lab to generate equal skid resistance level and predict the skid resistance level of a road surface after years under traffic.
According to the National Highway Traffic Safety Administration's Fatality Analysis Report System, more than 25 percent of fatal crashes occur on horizontal curves. High Friction Surface Treatments are an innovative, cost-effective, and sustainable means of improving roadway safety, which could improve the safety of this alignment. This research involved a comprehensive review of crash data to identify the correlation between pavement skid number, roadway curvature degree, crash rate, and crash severity. The dataset showed that greater injury occurred on higher degrees of curvature, and lower skid numbers correlated to a higher percent of wet road crashes. Also, around a skid number of 55, an increase in skid number no longer resulted in decreased crash rates. The goal of this research is to use these correlations to develop Crash Modification Factor that would integrate pavement friction and horizontal curvature, to enhance the accuracy of the current Highway Safety annual performance function.
Skid resistance is an important parameter for highway designs, construction, management, maintenance and safety. The purpose of this manuscript is to propose the correlation between skid resistance, which is measured as skid resistance trailer, and mean profile depth (MPD) or the macro surface texture, which is measured by vehicle mounted laser, so that highway agencies can predict the skid resistance of pavement without the use of expensive and time consuming skid resistance trailer, which also causes disruption of traffic in use. In this research skid numbers and MPD from 5 new asphalt pavements and 4 old asphalt pavements were collected using a locked wheel skid trailer and a vehicle mounted laser. Using the data collected, a correlation between the skid number (SN40R) collected by locked wheel skid tester and the texture data or MPD collected by a vehicle mounted laser operating at highway speeds was developed. The proposed correlation for new pavements was positive for MPD values less than 0.75 mm to reach a peak SN40R value, then there was a negative correlation as the MPD increases until the MPD value was equal to 1.1 mm and beyond the MPD value of 1.1 mm to the maximum value of 1.4 mm, SN40R value remained almost constant. There were significant data scatter for the MPD value of 0.8 mm. To explain these results, water film thickness during the friction test was calculated and the critical MPD was defined. The effect of sealed water pool on the SN40R was discussed. The test result showed a similar trend for older asphalt pavements, but with lower SN40R values due to the polishing of pavement micro-texture by traffic. Hence, a reduction factor was proposed for older pavements based on cumulative traffic volume for the above correlation to predict the skid resistance of older pavements.
There is a wide range of routine skid resistance measurement devices on the market. All of them are measuring the friction force between a rubber wheel and the wetted road surface. Common to all of them is that they are relatively complex and costly because generally a truck carrying a large water tank is needed to wet the surface with a defined water layer. Because of the limited amount of water they can carry they are limited in range. Besides that the measurement is depending on factors like water film thickness, temperature, measurement speed, rubber aging, rubber wear and even road evenness and curviness. All of these factors will affect the skid resistance and are difficult to control. We present a concept of contactless skid resistance measurement which is based on optical texture measurement and consists of two components: measurement of the pavement texture by means of an optical measuring system and calculation of the skid resistance based on the measured texture by means of a rubber friction model. The basic assumptions underlying the theoretical approach and the model itself based on the theory of Persson are presented. The concept is applied to a laboratory device called Wehner/Schulze (W/S) machine to prove the theoretical approach. The results are very promising. A strong indication could be provided that skid resistance could be measured without contact in the future.
Pavement friction is one of the primary factors that affect highway safety. Pavements with adequate surface friction reduce the number of wet skidding crashes. The objective of this study was to develop a predictive model for friction loss on pavement surfaces. The model incorporates parameters that describe aggregate shape characteristics, aggregate resistance to abrasion and polishing, aggregate gradation, and polishing cycles. This model was developed on the basis of the results of a comprehensive experimental program. Square-shaped slabs of different asphalt mixtures were prepared in the laboratory by using a linear kneading compactor and polished with a wheel-polishing device. The frictional characteristics of the surface of the test slabs were measured after different intervals of polishing, and statistical analysis was performed to relate friction to mixture and aggregate characteristics.
One of the most important properties of flexible pavements in terms of tire-pavement interface is surface texture. The texture of a pavement surface and its ability to resist polishing effect of traffic is of prime importance in providing skidding resistance. Pavement surface texture greatly contributes to tire-pavement skid resistance which has a direct effect on traffic operation and safety particularly at high speeds. Doubtless, there exists a close relationship between pavement surface texture and aggregate angularity within the wearing course. This paper is aimed to determine the effect of aggregate shape on the surface properties of Hot Mix Asphalt (HMA). Two different mineralogical types of aggregate (basalt and limestone) have been crushed with impact, jaw and roll type of crushers. Various types of aggregate with different shapes have been mixed with 50/70 penetration grade bitumen to form dense graded mixtures. Test methods related with the evaluation of shape and texture characteristics have been utilized to characterize the geometrical properties of aggregates. The texture and friction properties of asphalt slabs have been evaluated by means of sand patch test, 3D laser scanner and dynamic friction tester respectively. The results indicated that a relationship exists between the shape characteristics of aggregate and the surface properties of HMA.
Wet pavement skidding due to inadequate surface texture or friction contributes to 20% to 35% of all wet weather crashes. Many of the past studies of pavement surface texture and friction have deficiency in selecting the model forms or variables and interpreting the models and (or) the findings or have recommended further investigation. These pose a challenge for the highway agencies in selecting the appropriate surface layer and (or) measuring tools. This study was undertaken to re-examine some of the pavement surface texture and skid resistance related issues and aid the highway agencies in this area. Pavement surface texture and skid resistance aspects were carefully examined using the data collected from nine asphalt concrete (AC) surfaces. Pavement surface texture was measured using the sand patch method and a high speed texture laser. Skid resistance was measured using a British Pendulum and a skid trailer. The analysis has reinstated that aggregate quality is the predominant factor for AC surface skid resistance. Both texture depth and ribbed tire skid resistance was shown to increase with an increase in coarse aggregate (CA) content proving their interdependency. Neither the voids in mineral aggregate (VMA) or air voids (AV) contents showed a meaningful or statistically significant correlation with the surface texture or skid resistance. Fairly good correlations were found among the British Pendulum number (BPN), ribbed tire skid number (SN) and mean texture depth (MTD) rejecting the hypothesis that BPN is a measure of only surface microtexture and ribbed tire skid number is insensitive to surface texture.
We propose a new model to predict the evolution of pavement skid-resistance due to traffic polishing. The model accounts for polishing (by coupling a contact model with a wear law equation) and friction mechanisms. The contact model considers the tire operating conditions (including load, speed, and slip ratio), the tire geometry and mechanical behavior of the rubber tread, the pavement texture, and the physical properties of contaminants (i.e. the thickness and viscosity of fluids). The wear law considers the types of aggregates in the pavements (particularly their mineralogical composition) and the pressure distribution within the tire/pavement contact area. The friction component considers the mechanical behavior of a rubber measuring pad, the operating conditions during pad/pavement contact, and the pavement texture. The new predictive skid resistance evolution model is a numerical computational code that resolves pavement texture topographies at different polishing stages and the corresponding skid resistance levels. The model outcomes have been validated against repeated profilometer measurements on three mosaic pavements made of different types of aggregates subjected to the “Wehner-Schulz” procedure (that polishes and measures friction). The modeled predictions performed well against the captured changes in pavement textures during the polishing process, with slight differences in their absolute values potentially due to probable limitations of the wear law. The ability to predict the evolution of pavement skid resistance has transformative potential for tailored forecasting and proactive interventions to be undertaken across road networks.
In order to effectively improve the anti-skid performance of asphalt pavement, 88# calcined bauxite was introduced as a kind of high anti-skid aggregate, and the principle of differential polish was applied. With the self-developed three-wheel polishing device (TWPD), dynamic friction coefficient tester (DFT), accelerated stone polishing tester and AMES road laser texture scanner, the polishing performance and distribution maps of mean profile depth (MPD) of limestone and 88# calcined bauxite were obtained. The anti-skid performance of asphalt mixture blended with high and low polished stone value (PSV) aggregates was investigated. Before and after polishing, the MPD and estimated texture depth (ETD) of asphalt mixture blended with different proportions of 88# calcined bauxite were analyzed. The results show that the PSV of 88# calcined bauxite is significantly better than that of limestone. Based on different polished times, the relationship model between dynamic friction coefficient (DF) and vehicle speed was established. The model can reflect the relationship between friction coefficient, polishing times and vehicle speed well. Meanwhile, the reasonable proportion of 88# calcined bauxite is 25%∼ 50% mass of the mineral aggregate in asphalt mixture. The surface of asphalt mixture appeared obviously differential polishing effect, and the anti-skid performance of asphalt pavement was significantly improved. The obtained MPD and ETD values and the distribution maps of MPD were used to demonstrate the proposed optimal scheme. The research results provide new ideas for improving durability and anti-skid performance for asphalt pavement.
Pavement friction largely depends on surface texture characteristics, which are directly related to the corresponding aggregate properties. This study selected forty-five field pavement sites, which were constructed using seven typical types of aggregates available from eleven different quarries in Oklahoma, as the testing beds. Aggregate properties were characterized in the laboratory using the Aggregate Imaging System (AIMS), and pavement texture and friction data were collected in parallel in the field using a three-dimensional laser imaging system and Grip Tester. The traditional multivariate friction models were developed while several regression coefficients did not follow engineering judgment. Subsequently, the random forest analysis (RFA) was performed to evaluate the pavement surface friction subject to various aggregate properties. Loss of texture (%) is identified as the most significant aggregate characteristic for friction evaluation, accounting for 26.54% contribution to pavement surface friction. Traffic volume and temperature also exhibit significant impacts, with 31%, 14.7% contributions to pavement surface friction, respectively. This study is beneficial to better understand the effect of aggregate properties on pavement friction and to improve skid resistance performance in the field.
This paper aimed to combine drivers’ behavior and tire-pavement friction in different
weather conditions (dry and wet) to the analysis of microscopic simulated vehicular
conflicts. An assessment was proposed in terms of the proxy indicator of safety
“deceleration rate to avoid the crash” (DRAC), obtained from microscopic simulations
in a typical urban corridor. Saturation flow and free-flow speed were selected as the
calibration parameters for microsimulation to represent behavioral adjustments
according to weather. The coefficients of friction (dry and wet), measured by British
pendulum and sand patch for an arterial corridor, determined the maximum available
deceleration rate (MADR) for each conflict. This paper confirms a behavioral
adjustment due to rainfall (decrease in saturation flow). The DRAC values decreased
from dry to wet, indicating lower severity in wet conflicts. The MADR values increased
from lower to higher traffic volumes due to the reduction of speeds, which represents
higher friction coefficients. Even so, higher traffic volumes and wet conditions tend to
represent more DRAC>MADR conflicts, leading drivers to potentially perform evasive
maneuvers.
This study was attempted to investigate the influence of aggregate type and polishing level on the long–term skid resistance of thin friction course particularly with calcined bauxite. The PSV (Polished Stone Value) test, self-designed three wheel polishing device (TWPD) and dynamic friction tester (DFT) were applied to examine the friction performance of asphalt mixture and aggregate at different polishing cycles in laboratory. The mineral hardness of aggregate was linked with the skid resistance of aggregate and thin friction course by regression analysis. The grey correlation and t-test were utilized to evaluate the factors that influenced the skid resistance of thin friction course. It is found that better skid resistance value is observed for thin friction course by 88# calcined bauxite than by limestone, basalt and 75# calcined bauxite at each polishing level. PSV presents most significant influence for both terminal value and initial value of μ60. The PSV attenuation rate of aggregate has a strong correlation with the attenuation rate of μ40. The aggregate hardness parameter presents the ability of the aggregate and asphalt mixture to keep long–term skid resistance. In addition, calcined bauxite aggregate owns extensively applied potential in the thin friction course in China.
Texture is required on pavements to provide safe and comfortable ride performance for users. This paper provides the first meaningful analysis of a long-term study of texture data obtained using TRACS (TRAffic Speed Condition Survey) at a site in the UK. TRACS data were collected annually, over a 2 km stretch of motorway from 1995 to 2019. A new data analysis approach utilising time series data with spectral analysis and spatial filtering procedures is presented. The results reveal that the approach enables legacy TRACS laser profile Sensor Measured Texture Depth (SMTD) data to be used to determine long term rates of change in road surface macrotexture. Thus, the technique has unlocked the potential for SMTD data collected annually for 7000 km of the Strategic Road Network in the UK, to inform road maintenance programmes by extrapolation. Additionally, results expose a systematic periodicity occurring each year within the SMTD data studied, corresponding to longitudinal oscillations with wavelengths between 33 and 62 m. The time-invariant periodicity of these oscillations suggests that it is ‘imprinted’ in the early life of the pavement. ‘Imprinting’ may theoretically arise with cyclic tyre loading applied by the suspension systems of heavy vehicles or during road construction.
This article presented the latest development of testing methods concerning surface textures and skid resistance of asphalt pavements. A review of the repeatability and harmonization of field-testing methods for macrotexture is outlined. Measuring methods of skid resistance both in lab and in situ are reviewed. The harmonization research on the laboratory and field-testing methods are summarized. The recent progress of skid-resistance modeling of asphalt pavement from well-known research work is summarized. This article also suggests a few key research directions. First, compared with macrotexture, standard testing procedures for microtexture also need to be established for uniform and comparable characterization methods. Second, the gap between lab test and field test for skid resistance should be bridged to realize more accurate estimation of pavement frictional properties in the phase of lab design. There is the need for the International Friction Index (IFI) model to be reevaluated when the data is acquired from testers installed with ribbed tires. Third, the accurate tire modeling of the dynamically frictional contact between tire and pavement still needs to be improved. The parameters of pavement textures, traffic volume, water, hydroplaning, temperature, and friction law on tire-pavement friction should be considered in depth in the modeling aspect.
This study proposes a newly developed real-time testing system, namely, a tire-pavement dynamic friction analyzer (TDFA), to measure the dynamic friction coefficient between tire and pavement. Based on the self-developed TDFA, the friction coefficient between tire and pavement can be measured in real-time in the lab. A number of working conditions of tires were mimicked and tested. Subsequently, the effect of parameters such as tire load, tire pressure, actual tire-pavement contact area, tire speed, and slip ratio on pavement friction were investigated. It is found that there is a closely linear correlation between the actual tire-pavement contact area and the dynamic friction coefficient (DFC), and such correlation differs with the variation of pavement types. DFC usually has a negative linear relationship to tire speed. As slip ratio varies from 0% to 100%, the strongest correlation between DFC and Mean profile depth (MPD) can be found at the interval of 10%–15% slip ratio, which indicates that the pavement macrotexture also plays a role in the peak value of friction coefficient for the asphalt pavement. This testing method is very promising for the estimation of friction properties of pavement in the phase of lab mix design. It may also be used in the materials selection for pavement design.
Skid resistance is a key factor in road safety. Surface friction characteristics of roads are dependent on the microtexture and macrotexture of the surface. The decay of skid resistance with time is a function of traffic level and aggregate characteristics. This study developed predictive models for skid resistance of asphalt pavements and seal coat surfaces. The researchers examined the surface friction characteristics of 35 asphalt pavement test sections and 35 seal coat test sections. The skid number was measured using a skid trailer, while the microtexture and macrotexture of the test sections were measured using a dynamic friction tester and a circular texture meter, respectively. The Aggregate Image Measurement System (AIMS) and Micro-Deval test were also used to evaluate the aggregate shape properties and its resistance to polishing and abrasion. The developed skid prediction models express the skid number over time as a function of aggregate gradation, aggregate resistance to abrasion and polishing, and traffic level. The models showed good correlations with skid numbers measured in the field. These models can be used to optimise the mix design to provide adequate level of friction and estimate the skid number of asphalt pavements and seal coat surfaces over time.
Rapid detection and maintenance of pavement friction is essential for roadway crash prevention. Traditional measurement methods are time-consuming, labor-intensive, and inefficient. This paper proposes a new method to rapidly estimate pavement friction by using a light detection and ranging (LiDAR) sensor. Eight parameters are developed to capture the texture and material information of pavement. The British pendulum number is adopted as the reference of pavement friction with the data collection and processing approaches stated. An ordered logit regression model is utilized to estimate the level of pavement friction, with an average accuracy of 75.86%. The model shows that both textures and material information contribute to pavement friction. Some experimental tests are conducted to explore the potential impact of illumination, showing that lighting and road shading do not affect measurements. The proposed LiDAR-based method is able to assist for rapid, economical, and automatic estimation of pavement friction.
Pavement skid resistance is influenced by both pavement macrotexture and microtexture, with the two components providing the skid resistance properties required to assist in ensuring road safety. In addition to these factors the cumulative traffic along a pavement is a known determinant factor influencing pavement surface characteristics leading to deterioration. However, previous research efforts in this area have been evaluated based on laboratory experiments that have not proven to be easily extrapolated to represent field conditions. With this in mind, the present study aims to investigate and comprehend the long-term effect of cumulative traffic on both skid resistance and macrotexture evolution based on actual field measurements. The ultimate research goal is to develop a practical approach for analysis and interpretation of in-situ performance characteristics that could be utilized by road agencies in evaluating long-term skid resistance performance. For the investigation, an 11-year field dataset consisting of three categories of pavement sections defined by their traffic volume/characteristics and geometric design was analyzed. The analysis results showed that skid resistance and macrotexture can be separated into two defined zones during their evolution, which are determinant for the remainder of the pavement service-life. In addition, the varying characteristics of the three investigated cases were presented and a sensitivity analysis performed. Overall, knowledge gained from understanding the long-term field pavement performance can provide valuable information to road agencies for on-time pavement maintenance actions that can help ensure pavement sustainability. © National Academy of Sciences: Transportation Research Board 2019.
Pavement frictional behavior affects pavement performance in terms of vehicle safety, fuel consumption, and tire wear. Comprehending and interpreting pavement friction measurements is a challenging task, because of friction sensitivity to several uncontrollable factors. These factors include: pavement surface conditions, such as the type and thickness of contaminants and fluids on the surface and their interaction with friction forces; and the device operating conditions, such as sliding speed, material properties and geometry of the rubber slider used, and operating temperature. Despite the efforts to describe and quantify the impact of varying conditions on pavement friction, which ultimately will allow for a better harmonization of friction measurements, there is a need to better understand the link between the surface texture and physical friction measurements. In this paper, Persson’s friction model is used to analyze and understand the impact of surface texture on frictional behavior of dry pavement surfaces. The model was used to analyze 18 test locations, which were compared with the dry kinetic coefficients of friction (COF) estimated using a British pendulum tester (BPT). The results show that Persson’s friction model could predict the COF estimated from the BPT results with relatively high accuracy. In addition, the model could provide a profound explanation of the frictional forces mechanism. Finally, it was found that the mean profile depth (MPD) cannot provide a full picture of the frictional behavior. However, combining MPD with the Hurst exponent, texture measurements can potentially provide a full physical explanation of the frictional behavior for road surfaces.
Maintaining adequate level of skid resistance is essential for road safety. As part of their regular maintenance program, many departments of transportation collect skid data on roads to ensure sufficient traction between road surface and vehicle tires. This study developed models for skid resistance of asphalt mix and seal coat surfaces. These models express the skid number over time as a function of aggregate gradation, aggregate resistance to abrasion and polishing, and traffic level. The researchers examined 70 test sections in this study, half of which had an asphalt mix surface while the other half had seal coat surfaces. Skid data were collected using a skid trailer while surface friction characteristics of the test sections were evaluated using a dynamic friction tester and circular texture meter. In addition, the change in aggregate shape properties due to abrasion and polishing was studied using the Micro-Deval test and Aggregate Image Measurement System (AIMS). The results demonstrated that the developed models provide good correlation with the skid measurements in the field. This study produced a revised version of a utility called skid analysis of asphalt pavement (SAAP) that incorporates the new models for skid resistance of both asphalt mixes and seal coat. The SAAP can be used by pavement management agencies and contractors to estimate the skid resistance over time.
A state-of-the-art review of key parameters that influence measurement and modeling of skid resistance of asphalt pavements is provided. Tire-pavement interaction/friction is discussed and the current harmonization method of friction measurements questioned. The latest developments on pavement surface texture measurement and characterization are highlighted. A critical review of aggregate properties affecting friction, the frictional properties of asphalt mixtures and the influence of environmental factors on skid resistance is presented. An overview of modeling efforts entailing different aspects of tire-pavement friction is also presented. The frictional performance of asphalt pavements largely depends on the type and quality of coarse aggregates used. The different hot mix asphalt (HMA) classifications generally have similar microtextures. Their frictional performance follows the same order as their macrotextures. There is need for experimentally-validated skid resistance prediction models, especially for warm surfaces. Such models should account for tire and pavement surface texture characteristics, and the influence of environmental factors. Some other research needs are also identified.
Accurate modeling of tire-pavement contact behavior plays an important role in the analysis of pavement performance and vehicle stability control. A three-dimensional (3D) tire-pavement interaction model was developed using the FEM to analyze the forces and contact stresses generated during vehicle maneuvering (free rolling, braking/acceleration, and cornering). A pneumatic radial-ply tire structure with rubber and reinforcement was simulated. The steady-state, tire-rolling process was simulated using an Arbitrary Lagrangian Eulerian (ALE) formulation. An improved friction model that considers the effect of sliding speed on friction coefficients was implemented to analyze the effects of pavement surface friction on contact stresses, friction forces, and cornering forces. The results showed that the magnitudes and nonuniformity of contact stresses are affected by vehicle-maneuvering conditions. As the pavement surface friction increases, the tangential tire-pavement contact stresses at various rolling conditions (free rolling, braking/ acceleration, and cornering) and the vertical contact stresses at the cornering condition increase. It is reasonable to use the constant friction coefficient when predicting tire-pavement contact stresses at the free-rolling condition or at the cornering condition with small slip angles. However, it is important to use the sliding-velocity-dependent friction model when predicting the friction force at tire braking. (C) 2014 American Society of Civil Engineers.
Skid resistance of road surfaces depends mostly on pavement texture. This texture is usually divided to two components: microtexture and macrotexture. Microtexture refers to the small-scale texture of the road aggregate component while macrotexture refers to the large-scale texture of the road as a whole due to the aggregate particle arrangement. Both components contribute to the generation of friction between tyre and road. However, due to traffic, the first-cited component is continuously polished over the road's life. Maintaining that microtexture depends greatly on the aggregates used in the wearing course, the traffic level and the vehicle velocities. This work tries to quantify the influence of these three parameters on skid resistance degradation. Different specimens fabricated from different types of aggregates are submitted to different polishing pressure levels and velocities. From experimental results, an updated version of an existing model of skid resistance evolution is thereby proposed and validated. As a possible application of the new model, a prediction of damages induced by truck and passenger car traffic on skid resistance is proposed.
This paper presents improved analysis methods for characterizing asphalt pavement surface texture and focuses on the use of laser profiling techniques to estimate friction characteristics. Derived from signal
processing theories, texture spectral analysis methods show promise for improving characterization of the tire–pavement interface. Texture parameters measured with spectral analysis techniques represent a
means for quantifying surface properties. Current methods to analyze frictional properties rely on the mean profile depth (MPD) and mean texture depth (MTD) texture parameters. Although these parameters are used widely, they do not capture the range and distribution of surface asperities on the pavement surface. Knowing the distribution of surface asperities is critical for assessing friction characteristics. Thus, texture spectral analysis methods are anticipated to improve on the MPD and MTD parameters by capturing relevant texture-level distributions. This study investigates the applicability of laser profiling systems
for measuring pavement surface texture and subsequent relationships to friction. Models accounting for aggregate and mixture properties are developed and related to texture parameters through analysis of constructed field sections and corresponding laboratory samples. Results indicate that stationary laser profiling systems can capture the microtexture and macrotexture spectrum and suggest that a omprehensive
friction characterization of asphalt mixtures can be obtained in a laboratory setting. With this analysis system, it is believed that asphalt mixture designers will have an improved tool by which to estimate pavement surface texture and frictional properties.
Characterization of Aggregate Texture and Correlation with Surface Skid Resistance
- H R Sareh Kouchaki
- Joaquin Bernardo Hernandez
- Jorge A Prozzi
Sareh Kouchaki, H.R., Joaquin Bernardo Hernandez, Jorge A. Prozzi,
Characterization of Aggregate Texture and Correlation with Surface Skid
Resistance, Technical report 0-6878-3, TX Dot project number 0-6878.
Investigating the influence of distresses on long-term performance of pavement friction of rural roads in Ontario Canada
- Luciana Girardi Omar
Luciana Girardi Omar, A.E.H.O.A.E.H., Investigating the influence of distresses on
long-term performance of pavement friction of rural roads in Ontario Canada.
Transportation Research Board 2018. Washington, D.C., 2019.
Field evaluation of asphalt mixture skid resistance and its relationship to aggregate characteristics
- A R Eyad Masad
- Arif Chowdhury
Eyad Masad, A.R., Arif Chowdhury, Field evaluation of asphalt mixture skid
resistance and its relationship to aggregate characteristics, FHWA/TX-11/0-5627-3, 2011, Project 0-5627.
Incorporating road safety into pavement management: maximizing surface friction for road safety improvements
- David A Noyce
- Josue Yambo
- Jeremy Chapman
- Andrea Bill
David A. Noyce, H.U.B., Josue Yambo, Jeremy Chapman, Andrea Bill,
Incorporating road safety into pavement management: maximizing surface friction
for road safety improvements, MRUTC 04-04, Final Report, 8/2003 -6/2007.
Conversion model of axle load for high-grade highway traffic
- Jie
H.W.L.X.H. Jie, Conversion model of axle load for high-grade highway traffic,
Journal of Highway and Transportation Research and Development 23 (2006)
53-55.
Automated pavement friction estimation using mobile lidar
- Yishun Li
- Shengchuan Jiang
- Yu Shen
Yishun Li, Y.D., Shengchuan Jiang, Yu Shen. Automated pavement friction
estimation using mobile lidar, 2019 Annual Meeting of Transportation Research
Board, Washington D. C., U.S.A.
Characterization of Asphalt Pavement Surface Texture
- Timothy Miller
- D S Laith Tashman
- Nader Tabatabaee
- U Hussain
- Bahia
Timothy Miller, D.S., Laith Tashman, Nader Tabatabaee, Hussain U. Bahia,
Characterization of Asphalt Pavement Surface Texture, Transportation Research
Record: Journal of the Transportation Research Board, No. 2295, Transportation
Research Board of the National Academies, Washington, D.C., 2012, pp. 19-26.
Safety effects of pavement roughness for freeways: a comparative analysis of interstate highways in five states
- M.-A.-A. Jaeyoung Lee
M.-A.-A. Jaeyoung Lee, Safety effects of pavement roughness for freeways: a
comparative analysis of interstate highways in five states, Annual Meeting of
Transportation Research Board, C., U.S.A, Washington D, 2019.
Laboratory and Field Evaluation of Single Layer and Double Layer High Friction Surface Treatments
- P C Li
- Y U Demei
- R Xiong
- Y I Jiang
P.C. Shuo Li, Y.u. Demei, R. Xiong, Y.i. Jiang, Laboratory and Field Evaluation of
Single Layer and Double Layer High Friction Surface Treatments, Annual Meeting
of Transportation Research Board, C., U. S. A, Washington D, 2019.
A review: Pavement Surface Microtexture and its contribution to Surface Friction
- K C Shabnam Rajaei
- A Dargazany
- U S A Washington
K.C. Shabnam Rajaei, A. Roozbeh Dargazany, A review: Pavement Surface Microtexture and its contribution to Surface Friction, in, Annual Meeting of
Transportation Research Board, C., U. S. A, Washington D, 2017.