oliver(1989) also studied the seasonal variation of pavement friction in Australia using a British Pendulum Tester(BPT). This research project used a set of laboratory prepared surfaces resembling normal pavement surfaces, which covered a range of skid resistance values between 15 and 90 units, and a range of surface textures between 0 and 1.5 mm. These prepared surfaces were tested outdoors with temperatures ranging from 7 to 59 oc. This study observed a good correlation between the skid resistance value measured with the BPT and pavement temperature(Equation 2.7). The researchers suggested that temperature(air and pavement temperature) determines the rubber temperature, which affects the viscoelastic properties of rubber.