Study of fatigue behavior of geosynthetic-reinforced asphalt overlays using DIC analysis

• Grant number: 24/17130-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2025
• End date: December 31, 2025
• Field of knowledge: Engineering - Civil Engineering - Transportation Infrastructure
• Principal Investigator: Natalia de Souza Correia
• Grantee: Lucas Longo Agra Siqueira
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

In the last decade, the use of digital image correlation (DIC) or non-contact optical measurement techniques has become increasingly popular for investigating fracture phenomena in asphalt materials. It is known that the use of geosynthetic reinforcements significantly affects the response of asphalt overlays regarding the initiation and propagation of reflective cracking, and the use of techniques such as DIC can provide additional insights into the effects of reinforcements on the cracking phenomena of double-layer asphalt coatings. One relevant aspect is the monitoring of the strain field at the interface, made possible by this technique. Moreover, little is known about how the quality of interface shear bond (between the asphalt layers and the geosynthetic) affects the crack propagation mechanism in reinforced asphalt systems. The present research proposal aims to evaluate the initiation and propagation of cracks, as well as the strains mobilized in the cracking region during cyclic tests on asphalt slabs reinforced with geosynthetic through four-point bending (4PB) cyclic tests. For this purpose, a geosynthetic-reinforced pavement will be compared with a control section. Four-point bending tests, following ASTM D7460-10 specifications, under controlled stress mode, will be conducted at a frequency of 5 Hz on double-layer asphaltic samples extracted from Highway SP-225. To this end, real experimental sections were executed. Interface shear bond tests, such as Leutner shear tests, will be conducted in search of correlations between shear bond behavior and the crack potential of the asphalt slabs. This research aims to establish improvement factors related to the benefits of including geosynthetic reinforcement in mitigating reflective cracks and increasing the fatigue life of geosynthetic-reinforced asphalt systems.