Damage evaluation during installation of geosynthetics used in asphalt pavements

Geosynthetics are commonly used as anti-reflective cracking systems in asphalt pavements. The rehabilitation design methods use the characteristics of as-received geosynthetics as inputs. However, these materials undergo physical damage during their installation due to mechanical and thermal loads which currently are not taken into account in the design processes. These loads can produce a reduction in geosynthetic strength and therefore, it is necessary to know the secant modulus after installation in order to improve the pavement design incorporating these materials. The secant modulus of a material indicates its initial stiffness. This paper describes an experimental study of damage due to installation of five different geosynthetics using three different procedures: (i) mechanical damage induced in the laboratory considering the action of aggregates, (ii) in situ mechanical and thermal damage due to actual installation in a test section, and (iii) a new mechanical and thermal damage experimental test developed with the aim of reproducing the real installation conditions. The main results of the study indicate that the obtained secant modulus of the tested geosynthetics reduced after applying the three damage procedures, and the loss of properties differed depending on the type and constitutive material and on the applied damage procedure.This investigation was supported by the research Project ‘Rehabilitation of roads and highways (REHABCAR)’ file number IPT-370000–2010–029, led by DRAGADOS (ACS Group), in collaboration with GEOCISA and ASFALTOS AUGUSTA among others. The project has been funded by the Ministry of Economy and Competitiveness (MINECO) within the National Plan for Scientific Research, Development and Innovation 2008–2011 (INNPACTO 2010) and the European Union under ERDF Funds (European Regional Development Fund)