Recent studies have concluded that boundary lubrication is highly pertinent to
slipping and that adhesion and hysteresis are the main friction components in boundary
lubrication. To have a better knowledge about the mechanisms governing the boundary
lubrication friction at the microscopic asperity interaction level, a three dimensional
computational model of two rough surfaces is developed which calculates the friction
force due to hysteresis and real area of contact (which is proportional to adhesion
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friction). The computer model includes two rough surfaces of rubber and rigid material.
A viscoelastic material model based on parameters calculated from experiments is used to
simulate the shoe material. In addition, surface to surface contact algorithm is used for
simulating the interaction of the two rough surfaces. The results show that microscopic
shoe and floor roughness, followed by material properties, shoe sliding speed, and normal
loading affect hysteresis and adhesion coefficient of friction. The model provides an
improved insight about the mechanisms that cause changes in adhesion and hysteresis
when altering shoe and floor roughness, sliding speed, shoe material and normal loading
and it can be useful in development of slip resistant shoes and floorings