Rail corrugation is very prominent where you have steam, electric, and high speed rail. The most common factor in these three incidents is lack of traction or tractive effort. The propensity for corrugation development is greater at the track that carries empty or low loaded cars. Rail from different manufactures have shown different growth rates and density of rail plays a major factor. Rails with less tensile strength show lower corrugation then higher strength rails. But on the other hand our modern head hardened rail have a smaller propensity to form corrugations.