What is superelevation and why is it provided on curves?

Superelevation is the transverse slope provided on highway curves to counteract centrifugal force on vehicles. The outer edge of the curve is raised above the inner edge. It helps vehicles maintain stability while negotiating curves at design speed, reduces lateral friction demand, improves driver comfort, and allows use of higher speeds on curves. Maximum superelevation is typically 8-10% limited by slow traffic sliding inward and driver comfort.