The standards of the Swiss Association of Road Professionals (VSS) on the subject of pavement widening in curves dates back 20 years. Consequently they do not comply with actual cross-section standards and they basically do not correspond to the group of standards regarding the various types of roads. Thus, a general review of the subject is needed.

Swiss and foreign Experiences regarding the actual know-how on pavement widening are being analysed. In particular reference is being made to standards such as the German RAS-L-1995 and the Austrian RVS 3.23 respectively. Particular attention shall be given to the relevance of the following set of parameters:

• Track or pavement widening on the approach to the curve (cross-section design)
• Vehicle categories with similar dragging characteristics in curves
• Probability of vehicle crossings in curves
• Dragging of vehicles in short curves.

The investigation is based on both actual standards for cross-section design and space requirements in curves of the appropriate vehicle categories.

The actual research work comprises a proposal on the revision of the VSS - standard 640 105.