SAG Vertical Curve Calculator

Calculate the SAG vertical curve with our free online tool using the input parameters: Sight Distance, Roadway Grade, Headlight, Angle

Determine the minimum length of the SAG vertical curve by inputting the values of sight distance, roadway grade, height of headlight, and angle of headlight beam. This calculation will provide you with the required length of the SAG curve to ensure adequate visibility and safety based on the specified parameters.

Sight Distance
Initial Roadway Grade
Final Roadway Grade
Height of headlight
Angle of Headlight Beam
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    1 Number of calculations

    Lm = \frac{A \times S^2}{200 \times (H + S \times \tan(\beta))}
    Lm = 2S - \frac{200 \times (H + S \times \tan(\beta))}{A}

    The variables used in the formula are:

    A – Absolute difference between g2 and g1

    S – Sight Distance

    Lm – Minimum Curve Length

    H – Height of headlight

    β – Angle of Headlight Beam