# Construct curves

Use
the curve/circle tool to locate the curve where two
construction lines intersect.

Next, use the curve tool for horizontal
curve design by clicking on the ** **icon fro the toolbar. A
window allowing for curve radius input will pop up around the upper right corner
of the screen as shown in Figure 4(a).

## Figure 4(a) Curve setting input

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## Figure 4(b) Check minimum curve
radius

## Enter the desired
radius, for example 1110 ft, of the curve before you click on the left mouse
over the contour map. A message, as shown in Figure 4(b) will pop up if it does
not meet the minimum radius requirement. Click on the left mouse and drag the
curve/circle to a relatively close location where the curve will be constructed.
Construct two curves as shown in Figure 5. Note: The curve/circle does not need
to be placed exactly tangent to the lines. A curve alignment tool will be discussed and
used in next section to automatically compute the tangent points and align the
curve with the lines.

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## Note: Use right mouse clicking on a segment (line or curve)
to delete.

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## Figure Figure 5 Construct horizontal
curves/circles

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