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Wear Progression of Shoe Heels during Slip Resistance Measurements

Predicting changes in slip resistance performance with wear evolution is extremely difficult task and at present neither footwear nor flooring industries have a valid and reliable answer. Hence, in order to gain fundamental knowledge on wear mechanism, progressive wear and surface alteration processes of the shoes are investigated during repetitive dry rubbing. It is assumed that geometry changes of the shoe surface caused by wear development would be a major factor that affects the slip resistance performance. With the measurements of slip resistance, wear characteristics of two different shoes are comprehensively investigated based on the surface analyses and microscopic observations. For the systematic investigation of the surface alterations, topographic changes of each shoe were thoroughly examined on a regular time basis. The results show that surface alterations of each shoe were more severe than expected and occurred from the very early stage of sliding. It is also found that initially unstable friction process changed into the steady state friction process in the later stage of the slip resistance tests.