In Australia increased road usage and declining road expenditure place a strain on existing pavements and increase the need for cost effective pavement rehabilitation. Geotextile inter-layers incorporated with asphalt wearing courses and geotextile seals can inhibit cracking in both seals and asphalt wearing courses, and provide a waterproof membrane to prevent moisture ingress into the underlying pavement. This reduces the rate of degradation and extends the pavement's life. Geotextiles used in bituminous paving applications are subjected to extreme temperatures that are not typical of other geotextile applications. For example paving operations often occur above the cited melting temperature of polypropylene. The effect of exposure to paving temperatures on two geotextiles (polyester and polypropylene), and their effective application in bituminous paving works, is the subject of this paper. Duration and temperatures of geotextile exposure to elevated temperatures typical of field conditions were determined and a laboratory testing methodology devised to investigate effects of temperature on geotextile performance parameters such as strength, permeability and dimensional stability. It was found that the polyester geotextile was able to meet all performance criteria for temperatures up to 180 degrees Celsius and therefore it is suitable for use in both asphalt and sealing works. However the polypropylene geotextile was found to perform satisfactorily to around 140 degrees Celsius to 145 degrees Celsius and consequently is recommended for use only in asphaltic concrete applications where no polymer modified binders are used. (a)
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