Comportamento mecânico de misturas solo laterítico-cimento e resíduo de pó de vidro para aplicação em pavimentos

Abstract

The incorporation of glass powder waste (PV) into pavement construction emerges as a sustainable alternative for valorization of this type of waste and contributes to reducing environmental impacts. Although clayey soils and soil-cement-PV mixtures have been studied, their behavior under dynamic loads—especially in soils from southern Brazil—still requires investigation. With the implementation of the Brazilian Dimensioning Method (MEDINA), resilient modulus (MR) and permanent deformation (DP) tests have become essential for pavement design. This study evaluates the mechanical performance of a lateritic clay soil collected from the city of Pato Branco, Paraná, incorporating Portland cement (CP V) and PV. The experimental stage included physicochemical tests, as well as compaction and mechanical resistance tests. Tests of unconfined compressive strength (UCS) and diametral compression tensile strength (RTCD) were conducted on mixtures using 3%, 6%, and 9% of CP V, combined with 3%, 6%, and 12% of PV relative to the dry mass of the soil, compacted with three energies and subjected to curing periods of 7, 28, 90, and 180 days. Additionally, MR and DP tests were conducted on mixtures compacted with modified energy at 28 days of curing. The results show that the increase in compaction energy, cement content, and curing time elevated the UCS and RTCD. The 3% and 6% PV contents showed better performance after 180 days of curing, with values of 5.975 kPa and 4.905 kPa, respectively. The parameters qu and qt were correlated with the porosity/cement ratio, proving effective in predicting these properties. The average MR value for pure soil was 272 MPa, while the soil-cement-PV mixture (SC6%-PV3%) reached 439 MPa, considering the applied loads. The DP showed values below 1% in all soil-cement and soil-cement-PV mixtures. Based on the parameters obtained by regression for MR and DP, pavement structure design simulations using MEDINA indicated a up to a 50% reduction in base layer thickness—from 40 cm (pure soil) to 20 cm—when using soil-cement-PV mixtures (SC3%-PV6% and SC6%-PV3%). SEM analyzes show the formation of calcium silicate hydrates (CSH) and ettringite in mixtures containing cement and PV. These results confirm the feasibility of using these mixtures in base layers, since they met the fatigue and permanent deformation criteria for the projected service life.