Friction coefficient behaviour between rubber wheel and hydraulic concrete under different contact conditions

Currently, some countries are implementing the Bus Rapid Transit (BRT) system which combines the efficiency and quality of the Metro system and offers flexibility and low cost of infrastructure. To ensure the safety of users, the study of friction in pneumatic wheels in different environmental contaminants must be prove for these vehicles, since they carry out some fundamental functions like driving transmission, traction and braking. In this study, the behaviour of the coefficient of friction between SBR rubber and hydraulic concrete MR 48 was analysed in different contact conditions. Properties of SBR rubber were obtained with a universal testing machine and a durometer shore A, while the properties of concrete MR 48 were obtained with a compression testing machine. The friction experiments were performed by using the British pendulum method. Micrographs of the rubber surface were obtained by scanning electron microscope. The results showed that high values of coefficient of friction are obtained in dry condition and even higher at high temperature. Contrary, the lowest coefficients of friction were seen in wet condition and with contaminants. However, for the wet condition the coefficient of friction can recover after applying silica sand.