Proposed structural and functional evaluation of unpaved roads improved with geosynthetics, reclaimed asphalt pavement and Portland cement

Abstract

The cargo transport network in Brazil is highly unbalanced, with a marked concentration of road transport in relation to other modes of transport. As if the flagrant imbalance between modes were not enough, serious distortions are also observed in the distribution of road network coverage. Only 13% of the Brazilian network has coating considered definitive, reinforcing the importance of unpaved roads in the transport network. Despite advances, the design methods for unpaved roads were mostly developed for roads treated with gravel in regions with a temperate climate, which are inconsistent with the nature and behavior of Brazilian tropical soils. They also disregard important soil improvement techniques, such as reinforcement with geosynthetics, incorporating civil construction waste, reclaimed asphalt pavement, mining tailings or chemical stabilization with different additives (hydrated lime, Portland cement, latex polymers, organic additives and asphalt emulsion). Faced with this challenging scenario, this research was designed to monitor the structural and functional conditions of unpaved road test sections in Brazil built with different soil reinforcement and stabilization techniques. The structural condition of the test sections will be evaluated through deflection measurements with the Light Weight Deflectometer (LWD), Benkelman beam, and Falling Weight Deflectometer (FWD), and the functional condition will be evaluated through field inspections for the qualification and quantification of defects. This article aims to present the synthesis of the proposed methodology and the initial results of soil characterization obtained in constructing the first test section located in an unpaved section of the Federal Highway BR-030, in the state of Bahia.

Keywords

• unpaved roads
• soil improvement
• test sections