Pedestrian slip and vehicular skid resistance have been the focus of the highway community for several years in order to enhance pavement friction and safety at pavement crossings. The objective of this study was to assess the friction of alternative pavement markings used in Maryland in pedestrian crossings and to develop predictive models linking vehicular and pedestrian friction under varied conditions. The British Pendulum Tester (BPT) was used since the current state acceptance specifications use the British Pendulum Number. The investigation included laboratory and field testing of the most prevalent marking types used in the state. Results indicated that surface conditions (dry, wet, and icy) affected vehicular and pedestrian friction. Field results are consistent with the laboratory findings, in materials and surface conditions, permitting the development of models that relate lab and field results. This is particularly important since field testing requires traffic control with potential implications on cost and safety. The impact of traffic effects (i.e., locations on and off the wheel path) was also assessed to quantify deterioration trends in pedestrian slip resistance BPN(PSR) and vehicular tire–slip resistance BPN(TSR) under inservice polishing of pavement markings. Statistical analysis was used to assess the level of significance of the observed parameters and construct multiple linear regression (MLR) models, optimized using Box–Cox transformations, to improve residual normality and predictive accuracy. BPN(TSR) and BPN(PSR) models exhibited strong explanatory power (R2≥0.90) with low predictive deviations from measured values e.g., root mean squared error (RMSE) from 4.69 to 0.148 for TSR, providing confident friction predictions. Kolmogorov–Smirnov test results also indicated improved residual normality in the transformed models. This investigation provides valuable insights into crosswalk pavement markings friction and is expected to influence revisions in the current state specifications for these materials to account for pedestrian safety. This investigation is one of the few studies to jointly evaluate pedestrian slip and vehicular skid resistance, relate laboratory and field friction, and provide statistically validated predictive models for agency use.
Aljarrah et al. (Sun,) studied this question.