Improved Interpretation of British Pendulum Test Measurements for Evaluation of Floor Slip Resistance

摘要

The widely used British pendulum test (BPT) for pedestrian slip resistance evaluation obtains its measurements from a numerical reading scale and reports the test result as either a British pendulum number (BPN) or pendulum test value (PTV). There exist two issues that, if resolved, could significantly enhance the practical application value of BPT: (1) Different units of the BPT device could produce BPN readings with differences higher than 20 %, mainly due to their different slider force-deflection characteristics; (2) the relationship between BPN and coefficient of friction (COF) of the floor is nonlinear for a given BPT device, and it varies from one BPT device to another because of issue (1). This study demonstrates that, by means of a finite element BPT simulation model developed based on the theory of mechanics, the COF of a floor can be determined from the measured BPN of a BPT. It is shown that the commonly adopted practice of applying a single regression equation relating BPN to COF does not correctly represent the relationship between BPN and COF. This is because, in practice, different BPT devices would most likely have different slider force-deflection characteristics. The proposed simulation model approach would overcome this problem effectively by converting BPN measurements into COF, based on the respective slider force-deflection characteristics of the BPT devices concerned. In so doing, both issues (1) and (2) could be effectively resolved. Validation experiments were performed to confirm the validity of the simulation model and the COF calculated.