Transcription: To create a level road across variable height land, first consider the profile view of the land. Any land above the road, 120 meters, will need to be cut, and any land below needs to be filled. Filling the land below the road, elevation 115 meters, creates new elevation contour lines. If the fill ratio was 1 to 2, these new lines would appear as parallel to the road, but 10 meters away from it. The reason is that for every 5 meters drop in elevation due to fill, the toe of the fill moves out by 10 meters. The filling stops when the elevation of the land matches the fill elevation below the lan ...
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