Danos de instalação em geogrelhas de poliéster em agregado natural e fresado de revestimento asfáltico (RAP)

Abstract

Geogrids are frequently used as reinforcement elements in infrastructure projects and geotechnical structures, providing increased load-bearing capacity and reduced deformations. However, the reinforcement function of geogrids can be compromised by damage occurring during the field installation process. To ensure that the design strength of the reinforcement aligns with actual service conditions, these damages are accounted for in engineering designs through installation damage reduction factors (FRDI), which vary depending on the characteristics of the material comprising the backfill layer. However, there is a gap in understanding the reduction factors for geogrids when used with alternative materials, such as construction and demolition waste (RCD) or recycled asphalt pavement (RAP). In this context, this study aims to assess the mechanical damage caused by the installation of geogrids in compacted RAP aggregate layers, comparing them to conventional aggregates (sand) and analyzing the influence of the physical characteristics of RAP on the micro and macro damage observed in the reinforcement. To achieve this, experimental tests were conducted following the ASTM D5818-22 standard. The results indicate a significant loss of strength in the geogrids used with RAP, with installation damage reduction factors (FRDI) ranging from 1.36 to 1.59. Despite the coarser granulometry of RAP compared to sand, the FRDI values were not substantially higher. This suggests that the presence of the asphalt binder may have mitigated the impact of mechanical damage, reducing the severity of stress on the geogrids. The results obtained in this study highlight the importance of considering specific reduction factors for alternative backfill materials and reveal the significance of ensuring adequate quality of the polymeric coating on geogrids.