Evaluation Methodologies for Unpaved Road Surface Condition in Municipal District of Aquiraz, Ceará, Brazil

Abstract

Changes are described that were made in the evaluation method for unpaved surfaces developed by the U.S. Army Corps of Engineers (USACE) so that the method could be applied to the municipal district of Aquiraz, in Ceará, northeast Brazil. The main objective of these changes is to take advantage of the experience of USACE, reflected in the curves used to determine the deduct values from the defects, and to make adjustments according to a series of surveys involving endogenous variables (materials, topography, etc.) and exogenous variables (climate, traffic, etc.) for the unpaved road. The curves are nomograms representing the severity levels of each type of defect considered by the method, except for the dust excess defect. Seven curves are used to define an index of the road surface condition, called the unsurfaced road condition index, which is a function of the total deduct value. The ALYNOMO method, which was based on data obtained during studies of three unpaved roads located in the municipal district of Aquiraz, was compared with the USACE method to verify the changes made. A modification in the application principle of the USACE method was made so that it can provide evaluations identical (or very close) to those obtained by the ALYNOMO method. The new method is called VENO.