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PIARC (World Road Association), founded in 1909 and comprising 125 member governments from all over the world, is the global forum for exchange of knowledge and experience on roads, road transport policies and practices. With consultative status to the Economic and Social Council of the United Nations, the Association is contributing to a stable and sustainable global development of the road and transport sector.

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Term of the Road Dictionary

design speed

  • Language : PIARC Road Dictionary / English
  • Theme : Roads Design Geometry
  • Definition : Speed selected in designing a new road or in modernizing, strengthening or rehabilitating an existing road section, to determine the various geometric design features of the carriageway that allow a car to travel safely at that speed, under normal road surface and weather conditions. Note: the design speed is not constant, but may vary depending on the conditions of relief (plain, hill, mountain).