This research assesses the influence of temperature variation on GripTester (Findlay Irvine, Penicuik, Scotland) skid resistance measurements of asphalt pavements in Qatar. It evaluated a test road with six different sections and four major highways during winter and summer seasons with ambient temperature ranging from 18 to 44°C. Close-range photogrammetry (CRP) was employed for surface texture analysis using multiple pavement surface images and proprietary software. Differences in binder type and mixture design of the test road sections did not cause significant differences in skid resistance. The south-north (SN) direction of the test road had lower friction values during summer than winter. The opposite was the case for the north-south (NS) direction. The average friction and corresponding texture parameters in the NS direction were respectively 1.4 and 1.2 times higher than in the SN direction. The major highways generally had lower friction in summer than the following winter despite traffic polishing over time. The results suggest that the effect of temperature on skid resistance becomes pronounced when the grip number drops below 0.30 and surface texture decreases.

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Braking distance is one of the basic standards for road design and maintenance practices. Adequate tire-pavement skid resistance plays a significant role in reducing braking distance and consequently enhancing road safety. Several studies have shown the effect that some parameters, such as water film thickness, tire inflation pressure, and wheel load, have on braking distance. Less discussed is the effect of temperature which is of especial importance under hot weather conditions. The aim of this paper is to investigate the temperature effect on braking distance by means of the Finite Element (FE) method. A tire-pavement interaction FE model is proposed with the capability of considering the pavement textures and variations of surrounding temperature. Furthermore, the proposed model is validated by the field measurements carried out in the State of Qatar.@en

The skid resistance of a pavement surface is an important characteristic that influences traffic safety. Previous studies have shown that skid resistance varies with temperature. However, relatively limited work has been carried out to study the effect of temperature on skid resistance in hot climates. Recent developments in computing and computational methods have encouraged researchers to analyze the mechanics of the tire-pavement interaction phenomenon. The aim of this paper is to develop a thermo-mechanical tire pavement interaction model that would allow more robust and realistic modeling of skid resistance using the Finite Element (FE) method. The results of this model were validated using field tests that were performed in the State of Qatar. Consequently, the validated FE model was used to quantify the effect of factors such as speed, inflation pressure, wheel load, and ambient temperature on the skid resistance/braking distance. The developed model and analysis methods are expected to be valuable for road engineers to evaluate the skid resistance and braking distance for pavement management and performance prediction purposes.@en

The influence of test conditions such as test speed, pavement condition (wet or dry) and tire temperature on pavement friction measurements and texture-friction relationship was investigated. The skid resistance of an asphalt pavement section in Qatar was measured at test speeds of 35 and 50 km/h in dry and wet conditions, respectively, using a GripTester. The tire temperature was monitored using embedded small sensors. Close Range Photogrammetry (CRP) surface texture determination entailed using a camera for capturing pavement surface images, and analyzing the images with proprietary software. Both test conditions caused significant differences in grip numbers, but the average grip numbers fell within a narrow range (0.21–0.24). Among the texture parameters considered, only the peak material volume (Vmp) showed reasonable correlation (R = 0.61–0.78) with friction for both test conditions. The results suggest that the influence of test conditions on skid resistance decreases for smoothly polished pavement surfaces.@en

Braking distance is one of the basic standards for road design and maintenance practices. Adequate tire-pavement skid resistance plays a significant role in reducing braking distance and consequently enhancing road safety. Several studies have shown the effect that some parameters, such as water film thickness, tire inflation pressure, and wheel load, have on braking distance. Less discussed is the effect of temperature which is of especial importance under hot weather conditions. The aim of this paper is to investigate the temperature effect on braking distance by means of the Finite Element (FE) method. A tire-pavement interaction FE model is proposed with the capability of considering the pavement textures and variations of surrounding temperature. Furthermore, the proposed model is validated by the field measurements carried out in the State of Qatar.@en

The influence of test conditions such as test speed, pavement condition (wet or dry) and tire temperature on pavement friction measurements and texture-friction relationship was investigated. The skid resistance of an asphalt pavement section in Qatar was measured at test speeds of 35 and 50 km/h in dry and wet conditions, respectively, using a GripTester. The tire temperature was monitored using embedded small sensors. Close Range Photogrammetry (CRP) surface texture determination entailed using a camera for capturing pavement surface images, and analyzing the images with proprietary software. Both test conditions caused significant differences in grip numbers, but the average grip numbers fell within a narrow range (0.21–0.24). Among the texture parameters considered, only the peak material volume (Vmp) showed reasonable correlation (R = 0.61–0.78) with friction for both test conditions. The results suggest that the influence of test conditions on skid resistance decreases for smoothly polished pavement surfaces.@en

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.

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