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Highway And Railroad Engineering2D

Geometric Design: Vertical Alignment - Theory & Concepts - Sight Distance

Design of crest and sag vertical curves, calculating elevations, and ensuring adequate sight distance over hills and under bridges.

Open the complete lesson

Stopping Sight Distance (SSD) Simulator

Adjust the parameters to see how velocity, reaction time, road friction, and grade affect the total distance required for a vehicle to come to a complete stop.

60 km/h
2.5 s
0.35

(Lower = wet/slippery, Higher = dry/rough)

0%

(- = Downgrade, + = Upgrade)

Reaction Dist.
41.7 m
Braking Dist.
40.5 m
Total SSD
82.1 m

Visual Representation

250m Scale