Name: plotting a horizontal curve from field data
Uploaded: 2025-03-26T15:37:10.000Z
Duration: 1 min 9 s
Channel: JoVE

Consider that a civil engineer has to plot a simple horizontal curve with a 200-meter radius and a 20-degree intersection angle in the field.The engineer uses the method of perpendicular offsets from the long chord to plot the curve.&#160;First, the long chord length is calculated as 69.46 meters, and the intervals for perpendicular offsets are set at 3 meters.Next, the offset expression at the midpoint is used to determine the ordinate of the long chord&#8217;s center, and to ensure accuracy, this value is verified against the middle ordinate of the curve.The engineer marks the long chord of the curve on the ground, and the points at 3-meter intervals along both sides of the midpoint are marked.Then, the expression for the offset distance is used to calculate the perpendicular offsets, which are marked along the long chord at the corresponding points.Finally, the engineer connects the top ends of the perpendicular offsets to form the curve.

设计示例：使用设计数据设置曲线

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Designing and plotting a curve using field data requires precise calculations and execution. A horizontal curve with a radius of 200 meters and an ...

design-example-setting-a-curve-using-design-data

Education

教育

JoVE Core

Civil Engineering

土木工程

Unit 1

第一单元

Horizontal and Vertical Curves

平面曲线与纵断面曲线

KEY TERMS AND CONCEPTS

关键术语与概念

Design Example: Setting a Curve Using Design Data

plotting a horizontal curve from field data

Plotting a horizontal curve from field data starts with careful geometric design. The curve in this example has a radius of 200 meters and an intersection angle of 20 degrees. Engineers use the method of perpendicular offsets from the long chord to place the curve on the ground.

The long chord is the straight line between the two ends of the curve. Here, its length is calculated as 69.46 meters. To improve accuracy, 3-meter intervals are marked along the chord. Offset distances at each point are then found with the offset formula.

At the midpoint of the chord, the ordinate value is calculated and checked against the middle ordinate formula for the curve. This step helps confirm that the layout matches the design geometry. The long chord is then marked on the ground, and points are set at 3-meter intervals on both sides of the midpoint.

For each marked point, a perpendicular offset is measured at a right angle to the chord. The upper ends of these offsets show the curve position at each interval. When these points are joined smoothly, the curve is laid out on the ground according to the design specifications.

Plotting a Horizontal Curve from Field Data

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introduction to horizontal curves

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degree of curvature and radius of curvature

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introduction to vertical curves

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vertical curve: problem solving

Calculating Elevations on a Vertical Curve

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elevation-of-intermediate-points-on-vertical-curves

Finding High and Low Points on Vertical Curves

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design example: setting a curve using design data

Plotting a horizontal curve from field data starts with careful geometric design. The curve in this example has a radius of 200 meters and an intersection angle of 20 degrees. Engineers use the method of perpendicular offsets from the long chord to place the curve on the ground. The long chord is the straight line between the two ends of the curve. Here, its length is calculated as 69.46 meters. To improve accuracy, 3-meter intervals are marked along the chord. Offset distances at each point...

key terms and concepts

See how a 200 m horizontal curve is laid out from field data using a long chord, 3 m intervals, and perpendicular offsets for accurate ground marking.

Plotting a Horizontal Curve from Field Data | JoVE K12

JoVE Core Civil Engineering provides a foundational exploration of essential construction materials in civil engineering, focusing on bricks, stones, steel, wood, and concrete through easy-to-understand animated videos. This collection covers the properties, manufacturing processes, and practical applications of these materials. Additionally, the accompanied science-in-action videos demonstrate the research experiments performed in laboratories.

civil engineering

Plotting a Horizontal Curve from Field Data

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