Abstract:Restricted by the construction conditions, the small horizontal and vertical alignment indicators are often used for the urban roads. The curved sections of underground road and elevated road are affected by the mid-partition wall, side wall, structural roof or anti-collision wall, anti-dazzle facilities, sound barrier and other structures, which are easy to cause the poor sight distance and bring the potential safety hazard. On the basis of summarizing and analyzing the calculation method of the sight distance for driving and the required value of specification, the corresponding values of the horizontal curve and vertical curve radiuses of urban roads under the different design speeds and sight distance requirements are calculated and achieved by the numerical analysis. And the optimization design measures for the poor sight distance are put forward in order to provide the reference for the similar projects in the future.
