Superelevation is actually the amount by which the outer edge of a curve on a road or railroad is banked above the inner edge. This is the most important point when the highway is constructed and designed. The vehicles that will use the road need to be safe even they drive with high speed (limited by the road conditions). There are certain calculations needed to be done before the construction starts and exactly that angles to be build for best results. The images will show you more.

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