Roads and pavement

Several ASTM standards give methods of pavement testing and methods of result calculation. British pendulum tester is used to measure surface frictional properties. Pendulum slider is positioned in contact with the tested surface which was previously thoroughly cleaned and wetted. Rubber slider gliding on the surface causes a swing of drag point which increases with surface frictional properties increasing. Results are read from scale in British pendulum numbers. 

The Mu-meter is a trailer towed by vehicle. The tester measures the side force friction of pavement. The results are expressed as Mu numbers. Skid resistance of paved surfaces is measured by tester developed by North Carolina State University. This tester is a pendulum tester using a smooth rubber tire. The friction between the tire and the specimen is measured from the energy lost in pendulum. A standard specification for a smooth tire is covered in a separate standard.  

Variable slip technique is used to measure fiiction coefficient between tire and pavement. The test equipment consists of an automotive vehicle. Each test wheel contains variable brake system. The resulting resistive force caused by friction between the tire and the pavement surface is sampled and recalculated to slip friction numbers. Frictional properties of pavement surface as a function of speed are measured by dynamic friction tester. A disk spins with its plane parallel to the test surface. The rabber sliders come into contact with pavement, and torque is monitored when rotational velocity reduces due to friction. A graph of friction vs. speed is plotted. 

Calculation methods of international frictional index of pavement surface and international runway fiiction index are given. A spot measuring decelerome-ter is used for measurement of deceleration sustained by test vehicle while braking with all wheels locked. This method estimates effect of winter contaminated pavement. 

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As well as these, several industries have their own specifications aggregates [22], porcelain [23], ceramic powders [24], plastics [25], coating powders [26], concrete [27] and metals [28], The standard for glass spheres [29] is designed specifically for sieve analysis of glass spheres used in reflective road and pavement markings and other industrial uses. 

Terms delating to Materials for Roads and Pavements, ASTM Designation D8, American Society for Testing and Materials, Philadelphia, Pa., 1976. 

Aggregates for concrete including those for use in roads and pavements (prEN 12620)... 

Enhanced oil recovery by alkaline flooding was proposed some years ago as an inexpensive way to take advantage of the acid components that occur naturally in some crude oils [80,81]. The stabilization of oil-in-water emulsions can also be attained this way. In these cases the carboxylic acid contained in the crude oil adsorbs at the O/W interface, where it is neutralized into a carboxylic salt with surfactant properties such as interfacial tension lowering or emulsification. Fatty amines and their cationic counterparts at low pH are routinely used to stabilize asphalt emulsions for roads and pavement. 

ASTM D 8. 2013. Standard terminology relating to materials for roads and pavements. West Conshohocken, PA ASTM International. 

Illuminated motorways, roads and traffic control systems make our roads and pavements safe for vehicles and pedestrians... 

Mackerle, J. 1998. Finite element and boundary element analysis of bridges, roads and pavements - A bibliography (1994-1997). Finite Elements in Analysis and Design 29 65-83. 

Durability of concrete elements made with recycled aggregate may be lower when exposed to various aggressive media and should be carefully checked. In such a case, application of natural fine aggregate (natural sand) is preferable (Brozovsky et al. 2006). The use of recycled aggregate is very important for ecological reasons, but should be preceded by careful testing because with old concrete various deleterious influences may be introduced to new structures. The bulk application of recycled aggregate is Umited to secondary structures, e.g. as a sub-base for roads and pavements. 

TE15-T145 Highway engineering, Road and pavements... 

Advances in asphalt materials Road and pavement construction Edited by Shin-Che Huang and Hervi Di Benedetto... 

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