Skid Resistance and Surface Texture Deterioration of Urban Asphalt Pavements in Algeria: Assessment and Service Life Estimation

Abstract The Algerian pavement design Technical document prescribes a new wearing course after about 8–10 years, when undefined condition indicators decline. This study proposes friction-based indicators and a traffic-based model of the functional service life of asphalt wearing courses. Continuous longitudinal friction (61.1 lane-km) and 125 sand-patch tests were analysed on an urban expressway, an arterial and four interchange loops near Algiers and compared with investigatory levels from UK practice. Of the surveyed length, 66.7% had friction below 0.39 and 84.0% below 0.45. The median texture depth was 0.23 mm, so wet friction falls sharply with speed, and friction was uncorrelated with texture. A literature equilibrium polishing law was combined with an asymptotic time-decay law, Technical document traffic classes, lane factors, traffic growth, a light-vehicle polishing weight, a speed-dependent texture gate and the Technical document’s structural life. The model was run by Monte Carlo simulation. For 1500–3000 heavy vehicles/day/direction, PSV ≥ 60 is needed for an even chance of 8 years above the 0.40 level. Applied to 2018 counts at 11 Algiers stations (2,600–21,500 vehicles/day/direction, 1.5–13% heavy vehicles), the model predicts skid-governed lives below 20 years only on the two busiest roads. Its ranking agreed with an independent network model (r = 0.95). A simulated calibration study shows that 20 sections surveyed annually for five years would predict life within about 1.5 years. Skid resistance, not structural capacity, should trigger renewal on heavily trafficked roads, and minimum PSV and texture requirements should be added to the Technical document.