Name: setting out a horizontal curve
Uploaded: 2025-03-26T15:36:39.000Z
Duration: 1 min 3 s
Channel: JoVE

A horizontal curve has a radius of 400 meters, and the angle of intersection is 30 degrees, the station of point of curvature is 0 + 150 meters.The objective is to determine the stations of the point of intersection, point of tangency, and midpoint of the curve, as well as to calculate the length of the long chord.To identify the stations, the tangent distance and length of the curve are first calculated using the radius, and intersection angle of the curve.The station of the point of intersection is given by adding the length of the tangent to the station at the point of curvature.The station of the point of tangency is calculated by adding the length of the curve to the station at the point of curvature.Lastly, the station of the midpoint is found by adding half the curve's length to the station of the point of curvature.&nbsp;Then, the length of the long chord is obtained by the corresponding expression.

horizontal curve: problem solving

A horizontal curve is characterized by its radius, intersection angle, and stationing of key points. In this case, the radius is 400 meters, and the angle of intersection is 30 degrees, with the station of the point of curvature (P.C.) at 0 + 150 meters. The goal is to determine the station values at the point of intersection (P.I.), point of tangency (P.T.), and midpoint of the curve, as well as the length of the long chord.The process begins with calculating the tangent distance (T) and the length of the curve (L). The tangent distance depends on the radius and the tangent of half the intersection angle. The curve length depends on the radius and the intersection angle converted to radians.The station of the P.I. is found by adding the tangent distance to the station of P.C., and the station of P.T. is determined by adding the curve length to the station of P.C. The station of the midpoint of the curve is calculated by adding half the curve's length to the station of P.C.The length of the long chord, which spans the curve directly between the P.C. and P.T., is derived using trigonometric relationships involving the radius and intersection angle. These calculations ensure precise stationing and design integrity in setting out simple horizontal curves.

Horizontal Curve: Problem Solving

A horizontal curve is characterized by its radius, intersection angle, and stationing of key points. In this case, the radius is 400 meters, and the angle ...

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JoVE Core

Civil Engineering

Unit 1

Horizontal and Vertical Curves

KEY TERMS AND CONCEPTS

setting out a horizontal curve

A horizontal curve is set out by using its radius, intersection angle, and stationing of key points. In this example, the radius is 400 meters, the intersection angle is 30 degrees, and the station of the point of curvature, or P.C., is 0 + 150 meters. The goal is to find the station values for the point of intersection, or P.I., the point of tangency, or P.T., and the midpoint of the curve. The length of the long chord is also needed.

The first step is to calculate the tangent distance, T, and the curve length, L. Tangent distance depends on the radius and the tangent of half the intersection angle. Curve length depends on the radius and the intersection angle written in radians. These values are used to place the curve correctly in station form.

Next, the station of the P.I. is found by adding the tangent distance to the station of the P.C. The station of the P.T. is found by adding the curve length to the station of the P.C. The station of the midpoint of the curve is the P.C. station plus half of the curve length. The long chord, which stretches directly from the P.C. to the P.T., is found with trigonometric relationships that use the radius and the intersection angle. These calculations support accurate design and setting out of simple horizontal curves.

Setting Out a Horizontal Curve

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A horizontal curve is set out by using its radius, intersection angle, and stationing of key points. In this example, the radius is 400 meters, the intersection angle is 30 degrees, and the station of the point of curvature, or P.C., is 0 + 150 meters. The goal is to find the station values for the point of intersection, or P.I., the point of tangency, or P.T., and the midpoint of the curve. The length of the long chord is also needed. The first step is to calculate the tangent distance, T,...

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key terms and concepts

Find the P.I., P.T., midpoint, and long chord for a horizontal curve using radius, intersection angle, and stationing from the point of curvature.

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civil engineering

Setting Out a Horizontal Curve

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