Skid Resistance Values Research Articles

Evaluation of skid resistance of pervious concrete slabs under various winter conditions for driver and pedestrian users

Skid resistance of pervious concrete (PC) in comparison with traditional portland cement concrete (PCC) was investigated in the laboratory and in the field. Dry, wet, and iced PC surfaces were tested using the British Pendulum Tester (BPT) with two rubber sliders to represent driver and pedestrian users. Also, iced PC surfaces were treated with de- and anti-icing chemicals and then tested using BPT. Skid resistance values were recorded as the British Pendulum Number (BPN). PC slabs cast from one mix design in three compaction levels revealed that minimal correlation existed between PC porosity and BPN. Laboratory-cast PC slabs showed 23%, 27% and 97% higher BPN values relative to PCC slabs under dry, wet and icy surface conditions, respectively. After one icing event, the one-time application of anti- and de-icing agents on PC slabs improved their friction to the allowable BPN level using both MgCl2 and CaCl2. Field testing of five PC installations with various mix designs and surface conditions showed similar or slightly higher BPN than adjacent PCC slabs. Overall, the laboratory testing in this study showed it is possible to produce PC with significantly higher skid resistance relative to traditional concrete, the field testing revealed the importance of regular maintenance, aggregate type and mixture design on the skid resistance of pervious concrete.

Directional Skid Resistance Characteristics of Road Pavement: Implications for Friction Measurements by British Pendulum Tester and Dynamic Friction Tester

The British pendulum tester (BPT) and the dynamic friction tester (DFT) are commonly used to evaluate the polishing effect of traffic on pavement skid resistance. The present study was conducted to answer two questions: (i) whether the directional moving traffic action results in significant directional differences in skid resistance of the pavement, and (ii) if so, whether BPT and DFT are effective tools for evaluating the skid resistance performance of polished pavements with significant directional skid resistance characteristics. Five in-service pavement sections with different degrees of polishing were examined in this study. The following findings were obtained from the study: (a) There were statistically significant differences between the longitudinal and transverse skid resistance of the polished pavements tested; (b) there were no statistically significant differences between the longitudinal and transverse skid resistance of the newly paved unpolished pavement tested; (c) BPT was able to differentiate the directional skid resistance differences of the polished pavements tested; and (d) DFT was unable to differentiate the directional skid resistance differences of the polished pavements tested. DFT produces one skid resistance value for a circular path at each test point. The test results found that DFT over-estimated the traffic-direction skid resistance of in-service pavements. The over-estimation errors ranged from 0.001 to 0.023 DFT units, and the corresponding percent errors were from 0.4% to 11.1%. This finding suggests that the over-estimation effect of skid resistance directionality of polished pavements on DFT measurements should be recognized in pavement skid resistance evaluation and pavement safety studies.

The concept of pavement skid resistance state

The Concept of Skid Resistance State for highway pavements is introduced in this paper. The Concept states that at a given point in time, each unit length of a pavement has a fixed deterministic skid resistance value under a given set of pavement, environmental and vehicle operating conditions. A set of the operating conditions is defined by the following parameters: Vehicle tyre geometric and structural properties, wheel load, tyre pressure, vehicle speed, tyre slip ratio, tyre slip angle, pavement microtexture and macrotexture properties, ambient temperature, and pavement surface water film thickness. It is demonstrated in this study that, according to the proposed Concept, the skid resistance characteristics of a pavement can be fully described by a computer simulation model that analyses tyre–pavement–fluid interaction based on solid mechanics and fluid dynamics theories. Once the computer skid resistance model of a pavement section has been established, its skid resistance value under any vehicle–pavement–environmental operating condition can be calculated. Currently, there are already a number of computer skid resistance models developed by pavement researchers. Using one of these models for illustration, this paper explains how the Concept of Skid Resistance State is applied. The rationale, calibration process of the model, and input parameters are described; followed by a numerical demonstration of the establishment of the Skid Resistance State of an example pavement section. The significance and potential applications of the Concept on functional pavement mix design, pavement friction maintenance management, and harmonising of skid resistance measurements by different devices are also described.

An Evaluation of Relationship with Polished Stone Value and Skid Resistance Value Based on a Laboratory Investigation

Aggregates which are the main component of asphalt concrete play a major role in loading transfer and skid resistant performance of asphalt concrete. Therefore, reduction in friction resistance of aggregate would lead to a decrease in overall skid resistance of asphalt concrete which is a commonly used road pavement surface material. This research aims to evaluate relationship of aggregate friction capacity through the polished stone value and asphalt concrete skid resistance. In this study, a series of polished stone value tests on the study aggregate of limestone and sandy mudstone and British pendulum tests for skid resistance value of polished hot mix asphalt (HMA) slab. An accelerated polishing machine was used to create reduction of skid resistance of HMA slabs. Test results showed that reduction of polished stone value (PSV) of limestone 47.6% leads to a decrease of skid resistance value (SRV) approximately 43.8% of HMA slabs. Furthermore, 14.5% reduction of PSV of sandy mudstone causes a decrease of 20.3% SRV of HMA slabs. Finally, a relationship linear regression between PSV of aggregates and SRV of HMA slab was established.

Threshold value of skid resistance and texture depth for Malaysia road

Skid resistance is an important pavement characteristic for roads, which determines the friction between the road surface and vehicle tyres. The level of friction is largely influenced by the pavement surface aggregates micro texture, macro texture, and drainage attributes. The objective of this paper is to present the findings of the research and analysis conducted on Skid Resistance Value (SRV), Mean Texture Depth (MTD) and Skid Number (SN) obtained from the data collected on federal roads over the years since 2008. This research also attempted to determine the appropriate limiting values for SRV (microtexture), MTD (macrotexture) and SN for the federal roads. The result of analysis indicated that the average value of SRV at the locations of wet surface accident is 52.31 + 8.54. While for MTD, the accident risk is higher when MTD value is below the average of 0.45 + 0.025. The SRV and MTD results were correlated to each other and it can be concluded that accident risk increases significantly when SN value is below the average value of 31.49 + 7.87. Based on these findings, it is concluded that the minimum desirable values for SRV and SN for Malaysia’s Federal roads to be 55 and 30 respectively.

Experimental Investigation and Applied Research of Permeable Marking for Porous Asphalt Wearing Course

Abstract Porous asphalt wearing courses are a type of high-performance wearing course with technical features such as high skid resistance and low noise, as well as abilities that inhibit water mist during rainy weather conditions, prevent skidding during high-speed driving, and alleviate dazzle light during night driving. With the gradual popularization of this high-performance wearing course in China, the problem of its matched markings has become a growing concern. Hot melting scrape coating markings are commonly used in porous asphalt wearing course designs. However, this marking technology has associated problems. For example, its application often blocks the pores of the porous asphalt and causes surface water to gather on rainy days. It also attenuates the functional properties of porous asphalt. Additionally, material consumption increases because of marking infiltration. The proposed permeable marking technology addresses issues of performance concerning drainability, high skid resistance, and all-dimensional and all-weather reflection. Technical problems, such as pore blockage from ordinary markings, are successfully resolved by using an active bicomponent marking material through its reaction into membranes and in combination with rotating-coating type or discontinuous-extrusion type marking application technology. From the laboratory and in situ tests, it was determined that adhesion, reflection in the dark, wet driving conditions, and pavement skid-resistance value from the marking are improved.

Investigating the effect of temperature variations on the measured airfield pavement skid resistance

Airfield temperatures can range between −30 °C and +50 °C. Therefore, it is critical to correct the measured skid resistance values for field temperatures. To achieve this, several asphalt slabs were prepared and tested using the British Pendulum Tester. A special fluid was used to conduct skid resistance tests at below freezing temperatures. Test results were used to develop correction models for skid resistance under temperature variations, to be used by airfield operators. The results of this research are unique and important where it is the first time to include below freezing temperatures in skid resistance measurements and correction models.

Effect of cumulative traffic and statistical predictive modelling of field skid resistance

Skid resistance value (SRV) is a significant parameter representing the road safety condition. The measurement of SRV at different times after the construction is time-consuming and costly. To accurately predict the reduction of SRV, the SRV reduction model has been developed based on the aggregate and asphalt concrete mixture characteristics and field cumulative traffic volumes. In this study, three main types of aggregates typically used in pavements in Thailand, being limestone, granite and basalt were used to make asphalt concrete. The standard dense-grade asphalt concrete mixtures of 9.5 and 12.5 mm maximum aggregate sizes were designed and constructed at the studied sites (12 project sites located in 6 provinces). The SRVs were measured at every 50,000 passenger car unit (pcu) by the British pendulum tester for 3–4 years after the end of construction. Based on the statistical analysis of the test results, the SRV at various cumulative traffic volumes can be predicted using asphalt concrete mixture characteristics and initial SRV (after the end of construction) as prime parameters. The model will be recommended for inclusion in the Department of Rural Roads, Thailand preventive scheme for road safety management protocols.

Impact of Volcanic Ash on Road and Airfield Surface Skid Resistance

Volcanic ash deposited on paved surfaces during volcanic eruptions often compromises skid resistance, which is a major component of safety. We adopt the British pendulum test method in laboratory conditions to investigate the skid resistance of road asphalt and airfield concrete surfaces covered by volcanic ash sourced from various locations in New Zealand. Controlled variations in ash characteristics include type, depth, wetness, particle size and soluble components. We use Stone Mastic Asphalt (SMA) for most road surface experiments but also test porous asphalt, line-painted road surfaces, and a roller screed concrete mix used for airfields. Due to their importance for skid resistance, SMA surface macrotexture and microtexture are analysed with semi-quantitative image analysis, microscopy and a standardised sand patch volumetric test, which enables determination of the relative effectiveness of different cleaning techniques. We find that SMA surfaces covered by thin deposits (~1 mm) of ash result in skid resistance values slightly lower than those observed on wet uncontaminated surfaces. At these depths, a higher relative soluble content for low-crystalline ash and a coarser particle size results in lower skid resistance. Skid resistance results for relatively thicker deposits (3–5 mm) of non-vesiculated basaltic ash are similar to those for thin deposits. There are similarities between road asphalt and airfield concrete, although there is little difference in skid resistance between bare airfield surfaces and airfield surfaces covered by 1 mm of ash. Based on our findings, we provide recommendations for maintaining road safety and effective cleaning techniques in volcanic ash environments.

Gait of dairy cows on floors with different slipperiness.

This study assessed the slip resistance of different types of solid flooring in cattle housing using a range of technical tests and gait analysis. Dynamic and static coefficient of friction, skid resistance, and abrasiveness were tested on concrete flooring with a smooth finish, a grooved pattern, or a tamped pattern, acid-resistant mastic asphalt, soft rubber mats, and a worn slatted concrete floor. Coefficients of friction and skid resistance were tested under clean and slurry-soiled conditions. Linear kinematic variables were assessed in 40 cows with trackway measurements after the cows passed over the floors in a straight walk. All gait variables were assessed as deviations from those obtained on the slatted concrete floor, which was used as a baseline. The coefficient of friction tests divided the floors into 3 categories: concrete flooring, which had a low coefficient of friction (0.29-0.41); mastic asphalt flooring, which had medium values (0.38-0.45); and rubber mats, which had high values (0.49-0.57). The highest abrasion (g/10 m) was on the asphalt flooring (4.48), and the concrete flooring with a tamped pattern had significantly higher abrasiveness (2.77) than the other concrete floors (1.26-1.60). Lowest values on the skid-resistance tests (dry/wet) were for smooth concrete (79/35) and mastic asphalt (65/47), especially with a slurry layer on the surface. Gait analysis mainly differentiated floors with higher friction and abrasion by longer strides and better tracking. Step asymmetry was lower on floors with high skid-resistance values. The most secure cow gait, in almost every aspect, was observed on soft rubber mats. Relationships between gait variables and physical floor characteristics ranged from average to weak (partial correlations 0.54-0.16). Thus, none of the physical characteristics alone was informative enough to characterize slip resistance. With reference to gait analysis, the abrasiveness of the hard surfaces was more informative than the coefficient of friction, but the effect of pattern was better detected by skid-resistance measurements. Consequently, several physical characteristics are needed to objectively describe the slip resistance of cattle floors. Soft rubber mats gave better tracking than hard, solid floors, even with a grooved surface or a tamped pattern.

Prediction of Skid Resistance Value of Glass Fiber-Reinforced Tiling Materials

This research focuses on the use of adaptive artificial neural network system for evaluating the skid resistance value (British Pendulum Number; BPN) of the glass fiber-reinforced tiling materials. During the creation of the neural model, four main factors were considered: fiber, calcium carbonate content, sand blasting, and polishing properties of the specimens. The model was trained, tested, and compared with the on-site test results. As per the comparison of the outcomes of the study, the analysis and on-site test results showed that there is a great potential for the prediction of BPN of glass fiber-reinforced tiling materials by using developed neural system.

Korelasi Skid Resistance dengan Kedalaman Tekstur pada Permukaan Perkerasan Lentur

Skid Resistance is the force generated between the pavement surface and vehicle’s tires to resist the vehicle advance motion when braking. In this research the correlation between skid resistance value and texture depth on the pavement surface will be determined. The skid resistance value determined by using the British Pendulum Tester (BPT) and to determine the texture depth used Sand Patch Method. The research is conducted directly on a macro textured surface with two methods. The first method is applied on Ngumban Surbakti Road where the samples tested with the same distance from the edge of the pavement along the road; The second method is applied on Jend. Sudirman Road where the samples tested with specific distances from the edge of the pavement until the median. From the results of the analysis, there are some conclusions: (1) there is a positive correlation between the texture depth and skid resistance with a coefficient of determination (R2) = 0.028 on Ngumban Surbakti Road and (R2) = 0.191 on Jend. Sudirman Road;(2) the increase of skid resistance value is directly proportional to the increase of surface texture depth value; and (3) the different methods did not cause significant yield differences.

Pavement skid resistance consideration in rain-related wet-weather speed limits determination

Posted maximum speed limits used by highway agencies worldwide are typically applicable to dry-weather driving conditions. During wet weather, these speed limits may exceed the maximum speed for safe traffic operations. More and more highway agencies are employing variable speed limits as a means to improve wet-weather driving safety. For rain-related wet-weather conditions, the variable speed limit systems in use today commonly set speed limits based on either consideration of stopping sight distance, or past experience and engineering judgement. A common shortcoming of the existing systems is that the actual pavement skid resistance characteristics are not considered in setting the speed limits. This paper proposes an improved procedure to derive mechanistically the speed limits from the required safe stopping distance as well as the minimum skid resistance requirement for safe driving, based on the actual skid resistance properties of the pavement considered. The proposed procedure makes use of a finite-element skid resistance computer simulation model to determine both the available skid resistance values and vehicle braking distances at different vehicle speeds of the in-service pavement under specified rain-related wet-weather conditions. The procedure is theoretically sound, and is consistent with the concept of pavement network friction management system. In the analysis, the rain-related wet-weather condition is represented by rainfall intensity, and the road section is characterised by its gradient and cross slope, as well as the skid resistance properties of the pavement. A numerical example is presented to illustrate the working of the proposed procedure.

Skid Resistance of Asphalt Concrete at the Construction Stage Based on Thai Aggregates

AbstractIn Thailand, the skid resistance in road pavements requires considerable improvement in order to increase road network safety. However, skid-resistance values can only be measured in situ, ...

Incorporating Pavement Skid Resistance and Hydroplaning Risk Considerations in Asphalt Mix Design

AbstractAn analytical framework and procedure is proposed in this paper to incorporate pavement skid resistance requirements in asphalt mix design, as part of the overall asphalt pavement design process. The concept is introduced with the aim to overcome the inadequacy of current pavement design procedures, asphalt mix design in particular, in addressing pavement-related highway functional safety requirements. Central to the concept is the use of a theoretically derived finite-element simulation model to generate the skid resistance performance curve (i.e., skid resistance–speed relationship for a given water film thickness) of a pavement surface mix design, based on the input of two skid resistance values measured at different test speeds. Three highway functional safety requirements are addressed, namely the minimum safe terminal skid resistance, the maximum braking distance allowed, and the minimum hydroplaning speed. The proposed framework comprises three main components: (1) a laboratory-accelerated ...

Performance Evaluation of Gravel Road Sections Sealed with Surface Dressing

The rural population of India lack adequate transport infrastructure to access the nearby towns/headquarters. The Ministry of Rural Development (MoRD), Government of India (GoI) decided to develop various rural roads under Pradhan Mantri Gram Sadak Yojna (PMGSY). The main objective of PMGSY is to achieve all weather connectivity to all habitations. Hence, a pilot study was initiated over a 7 km gravel road stretch from “Ghanapur-Palakurthy Public Works Department (PWD) Road to Komatigudem via Ippagudem, and Rangaraigudem” in the Warangal district of Telangana State, India. There are various disadvantages associated with construction using gravel like dust generation and gravel loss over a period of time due to passage of vehicles. The best solution to minimize these problems is to seal the gravel roads. The pilot road considered in this study was constructed using locally available gravel up to the surface course and then sealed using surface dressing. The performance of the road sections were evaluated in terms of roughness, skid resistance, and texture depth. The initial set of data was collected immediately after construction and one month after construction. Later, four sets of pavement performance data was collected after seven months of construction of the surface dressing layer in November 2013, January 2014, April 2014, and June 2014. Altogether, six sets of data were collected. The data was analyzed and important observations are reported in this paper. There is a considerable change in surface texture and skid resistance values after the first one month of construction whereas no significant changes were observed in the roughness values. Further, there is no significant difference in the results of surface texture, skid resistance and roughness values when the pavement sub-sections were evaluated for four times even after seven months of construction of the sealing layer.

보도포장의 종류에 따른 보행자의 안전성 및 쾌적감에 대한 연구

Safety, resilience and comfort of pedestrian were assessed by the British Pendulum Test and SB/GB factor test at 8 kinds of sidewalk pavement. Sidewalk paving materials were normal concrete, porous concrete, concrete block, soil concrete, asphalt, rubber chip/resin mixture, wood chip/resin mixture and floor tile. In addition, a survey was conducted to investigate the perception of pedestrians on the sidewalk paving material. As a result, while the skid resistance value was measured in the most 60BPN above, the floor tile showed a low value of about 30BPN. The ratios of SB factor to GB factor of the elastic pavements(rubber/resin mixture and wood chip/resin mixture) appeared to be relatively large when compared with those of the conventional sidewalks. The survey showed that respondents perceived as more safe and comfortable elastic pavements compared to conventional pavements. Approximately 50% of respondents answered that hardened soil pavement was the most environmentally friendly.

Analysis of Surface Properties Determining Slip Resistance of Ceramic Tiles

Slip resistance tests of pavements form an important part of Construction Products Regulation (CPR) in the EU. Measuring slipperiness is a complex problem. This property is often incomplete or inaccurate. The paper presents new test results of glazed and unglazed ceramic tiles with natural, polished and textured surfaces tested in dry, wet and oily conditions. In the research 3 dierent methods of slip resistance tests were used providing the average angle of inclination, skid-resistance value and coecient of friction. The results show that surface roughness was also a significant factor aecting slipperiness. It is necessary to examine the structure of materials that is why measuring cleanability, as an important contributor to slip resistance and surface roughness, is fundamental in this research. Based on the experiments, it was found out that multiple cycles of sodium hypochlorite treatment could modify the surface of ceramic tiles.

Skid-Resistance and Noise-Reducing Characteristics of Exposed-Aggregate Cement Concrete Pavement

EACCP is a new-type cement concrete pavement with better skid-resistance and less traffic noise. In this paper, skid-resistance and noise-reducing performance of EACCP are tested and analyzed by laboratory and outdoor tests. The results indicate that the relationship between BPN and EAD is followed the parabola variation laws. With the increase of EAD, TD decreases. And skid-resistance value exists the extremum. If BPN is targeted as skid-resistance optimization goal for pavement surface features, the optimized EAD is existed and approximately to 40~60. The relationship between BPN and TD is also followed the parabola variation laws which also suggests the existence of the optimized TD scope approximately to 0.8~1.0mm.The relationship between TD and EAD can be simulated by index variation laws. With the increase of EAD, TD decreases, which proves the evident noise-reducing performance of EACCP. And the reduction amplitude of noise increases with vehicular acceleration.

Considering Safety Impacts of Skid Resistance in Decision-Making Processes for Pavement Management

With the increase in material and labor costs and the decrease in purchasing power, the Texas Department of Transportation (DOT) is striving to maintain its roadways at the current level of conditions within a severely constrained budget. In particular, maintaining adequate pavement skid resistance has become a challenge for decision makers at various levels. The goal of this study was to develop a methodological procedure that could be used to establish the appropriate threshold values for skid resistance so that safety would not be compromised on Texas highways when there is a budget shortfall. The two primary issues were to be addressed: ( a) identification of the quantitative relationship between pavement skid resistance and crash rates and ( b) determination of threshold values for skid resistance and corresponding recommendations for maintenance decisions. A detailed methodological framework was proposed. Highway segments were categorized into homogenous groups of safety-related characteristics, except skid resistance. The quantitative relationship between crash risks and skid resistance was then established with the concept of the crash rate ratio. Three threshold values were determined to establish four decision categories of skid resistance values, with crash and skid resistance data collected from 2008 to 2011 on the highway system maintained by the Texas DOT. Corresponding recommendations on maintenance decisions were provided. The results show that the proposed methodological procedure can effectively capture the safety impacts of skid resistance at the network level and provide a useful tool for the Texas DOT to take safety into its maintenance decision-making processes.