The influence of binder rise in reducing tyre-road friction

摘要

Research undertaken between 2007 and 2009 examined the influence of binder rise in reducing tyre-road friction of chipseal surfaces. The emphasis was on the most extreme form of binder rise when the binder is level or above the sealing chip, resulting in the formation of a black, slick surface. This condition is referred to as flushing. The aims of the research were to: 1. identify the best statistic to detect flushing from two-dimensional (2D) road surface profiles measured with lasers; 2. establish whether the dynamic friction tester (DFT) can sufficiently simulate high-speed locked-wheel braking (LWB) performance to enable its use for investigating friction characteristics of flushed sections of chipseal roads; 3. quantify the reduction in dry and wet road friction of chipseal road surfaces caused by the presence of flushing.