AASHTO R 40

Abstract

The rod and level can be used to accurately measure the profile of a pavement. The profile data can be used to evaluate the roughness of the pavement by computing a roughness index such as the International Roughness Index (IRI) or to evaluate effects such as frost heave or swelling of soils. In computing roughness indices, only the relative elevations and not the absolute elevations are needed. The guidelines in this standard practice can be applied to conventional survey equipment such as an optical level and graduated staff, which require the readings to be manually recorded, as well as automated equipment that is capable of automatically storing the measured data. <br><em>This standard practice may involve hazardous materials, operations, and equipment. It does not purport to address all of the safety concerns associated with its use. It is the responsibility of the user of this standard practice to consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.</em>