Transition Curve Deflection Angle – Necessary for Passenger Safety

• Length of spiral from tangent to any point (L)

• Length of spiral (L_s)

• Radius of Simple Curve (R)

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• Deflection angle to any point on the curve(i)

  

Formula:

i = L² / ( 6×R×L_s)

  Where,

     i - Tangent deflection angle to any point on the curve

     L - Length of spiral from tangent to any point

     L_s - Length of spiral

     R - Radius of Simple Curve

Use this online calculator to know how to use spiral curve to gradually change the curvature and super elevation of road and this is also known as transition curve.