Since July 1992, it has been possible for Local Authorities to apply to DOT for authorisation to use non-standard road humps such as `thumps' and speed cushions in traffic calming schemes. Standard circular profile road humps have been widely used in the UK, but they can be relatively expensive to install. Circular profile thermoplastic humps, (`thumps') 37 mm high by 900 mm in the direction of travel, were first used experimentally as a lower cost alternative by Wakefield MDC on Manygates Lane in 1990. The results were encouraging and therefore TRL included `thumps' in a track trial held at TRL in November 1992. Following the track trials, the DOT funded the installation and monitoring of on-road trials of `thumps' in order to further investigate the effectiveness of `thumps' as speed reducing devices and their effects on buses, emergency service vehicles and two-wheeled vehicles. Wakefield Metropolitan District Council assisted with these on-road trials and installed a series of `thumps' along a road in South Elmsall, West Yorkshire. The results of the Wakefield trials are given in this report together with results from a further 4 sites where thumps have been used. A brief comparison between `thumps' and 50 mm high standard circular profile humps with tapered edges is also included. Speeds and accidents have been reduced at the sites studied, but it is apparent that `thumps' can have opposition from bus companies, which may lead to the Authority removing the `thumps'. (A)
Abstract