Hemler S L, Pliner E M, Redfern M S, Haight J M, Beschorner K E
Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA.
Department of Biomedical Engineering, University of Florida, FL, USA.
Footwear Sci. 2022;14(1):1-12. doi: 10.1080/19424280.2021.1994022. Epub 2021 Nov 11.
Footwear outsole design is an important factor for shoe-floor friction and for preventing slipping. Shoes with small, uniformly-separated tread blocks (often included on slip-resistant shoes) have decreased slip risk due to their increased friction and better under-shoe fluid drainage. However, these traction performance metrics (friction and fluid drainage) diminish with wear. This study quantifies shoe traction performance in response to natural wear and compares the relationship between common wear metrics: time, distance walked, and worn region size (WRS). Participants wore two pairs of shoes in the workplace for up to 11 months and the distance walked was tracked with a pedometer. After each month of wear, traction performance and WRS of each shoe were measured. Traction performance was quantified by the under-shoe available coefficient of friction and fluid force during a simulated slip condition. Increased wear (months worn, distance walked, and WRS) was associated with decreased traction performance. A WRS of 800 mm was associated with reductions in friction of 16-38% and increases in fluid force by 286-528%. Three and six months of wear were associated with WRS values of 251 mm and 462 mm and distances of 203 km and 519 km, respectively. A walking distance of 500 km was associated with a WRS of 406 mm. This study showed that all these wear metrics are good indicators of shoe traction performance loss. Thus, the most practical metric in a particular application can be selected. We argue that WRS may be the best indicator due to variations in wear rate from the user and environment. Therefore, tracking footwear usage and monitoring outsole wear can aid in shoe replacement recommendations to reduce slips and falls.
鞋底设计是影响鞋与地面摩擦力以及防止滑倒的重要因素。带有小的、均匀分布的防滑花纹块的鞋子（防滑鞋通常具备）因摩擦力增加和更好的鞋底排水性能而降低了滑倒风险。然而，这些防滑性能指标（摩擦力和排水性能）会随着磨损而降低。本研究量化了鞋子在自然磨损情况下的防滑性能，并比较了常见磨损指标之间的关系：时间、行走距离和磨损区域大小（WRS）。参与者在工作场所穿着两双鞋子长达11个月，并用计步器记录行走距离。在每个月的磨损之后，测量每只鞋子的防滑性能和WRS。防滑性能通过模拟滑倒情况下鞋底的有效摩擦系数和流体力来量化。磨损增加（磨损月数、行走距离和WRS）与防滑性能下降相关。WRS为800毫米时，摩擦力降低16 - 38%，流体力增加286 - 528%。磨损三个月和六个月时，WRS值分别为251毫米和462毫米，行走距离分别为203公里和519公里。行走500公里的距离与406毫米的WRS相关。这项研究表明，所有这些磨损指标都是鞋子防滑性能损失的良好指标。因此，可以在特定应用中选择最实用的指标。我们认为，由于用户和环境导致的磨损率差异，WRS可能是最佳指标。因此，跟踪鞋类使用情况并监测鞋底磨损有助于提出更换鞋子的建议，以减少滑倒和跌倒。
