Superelevation / Min Curve Radius (AASHTO)

Formula and source

e + f = V^2/(15 R); required e = V^2/(15 R) - f; minimum radius R_min = V^2/(15(e_max + f)). V in mph, R in ft.

The AASHTO A Policy on Geometric Design of Highways and Streets (the Green Book) point-mass curve model, by name.

Audience

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Related tools

• Horizontal Curve Layout
• Crest Vertical Curve Length for SSD (AASHTO)
• Horizontal Sightline Offset on a Curve (AASHTO)
• Stopping Sight Distance (AASHTO)

Posture

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