Fracture strength of geogrid-reinforced concrete pavements with carbon-fiber composites insertion

ABSTRACT

Repeated and multiple traffic loads, along with climatic conditions, influence the mechanical behavior of linear pavements, leading to the formation of cracks that propagate significantly across the wearing surface and result in a loss of load-bearing capacity of the pavement body. To remedy this problem, various reinforcement and repair methods (traditional and modern) are applied to address this issue. The use of geogrids, involving the insertion of sheets at the interfaces of the sub-base layers, has proven effective as an alternative solution due to their mechanical and aesthetic performance. However, these geogrids, primarily serving as a separation layer, are sometimes limited in the gains they make in reducing stresses and strains, since these gains do not exceed 5 to 10%. Consequently, researchers have sought other techniques that provide both separation (to prevent crack propagation) and strengthening (to increase the bearing capacity of the pavement). In this article, we propose to study the reinforcement of rigid cement concrete pavements through an experimental approach, using two laboratory batches, each comprising a number of twenty-two (22) small-scale slabs, with dimensions of 400 × 400 × 50 (mm). The first batch was produced at an ambient temperature of 20°C while the second batch was produced at an elevated temperature of 50°C (arid climate). These slabs will be tested in 4-point bending, after reinforcement with different combinations of geogrids and carbon fibers composites. To compare the experimental results obtained, a numerical simulation based on the finite element method, using appropriate software, was conducted. The results regarding stresses and strains, as well as dissipation energy, showed that the combination adopted is very effective, yielding gains of up to 20 to 35%, additionally the integration of geogrids, with the addition of the composite, enhances the reinforced pavement’s longevity, ensuring long-term savings on its upkeep and maintenance.

Keywords:
Concrete Pavement; Geogrid; Composite; Experimental Test; Numerical Analysis