Evaluation of Norwegian gradation based regulation for frost susceptibility of crushed rock aggregates in roads and railways

Abstract

Norwegian road and railway construction practice has significantly changed during the last 40 years due to the replacement of natural gravel by crushed rock material as main aggregates in base, sub-base and frost protection layers. The frost susceptibility criteria and thermal properties considerations have however not evolved accordingly to intrinsic characteristics of the new material. This article will first give an overview of main challenges and concerns with existing Norwegian regulation. Secondly, the Frost Protection for Roads and Railways research project is presented, followed by the description of a full-scale instrumented test site. Main goal of the paper is to indicate the challenges posed by the current regulation and to propose research investigations in order to improve it.