Engineering, Civil and Structural Engineering, Computational Mechanics, Ceramics and Composites
43
Scopus Publications
Scopus Publications
Urban waste to construction material: Casuarina equisetifolia cone ash in coating mortars Mariana Almeida de Azevedo Pessôa, Gustavo de Castro Xavier, Marcela da Silva Luna Paravidino, Laimara da Silva Barroso, Niander Aguiar Cerqueira, et al. Environmental Science and Pollution Research, 2026 This study investigates the potential use of Casuarina equisetifolia cone bottom ash (CC-BA) as an additional material in rendering mortars for wall and ceiling applications. A bibliometric analysis revealed a significant lack of research on the topic. Casuarina cones, widely dispersed in urban areas, pose a public maintenance burden but can be used as fuel, producing ash with potential applications in construction. Mortars were prepared with a 1:6 cement-to-sand ratio, incorporating 5 to 25% CC-BA by weight relative to the mass of cement, in addition to a reference mix (CPII-00). The materials underwent physical, chemical, and microstructural characterizations. Fresh-state testing indicated satisfactory workability up to 15% CC-BA, with CPII-10 yielding the best results. All compositions met the consistency index requirements, although water demand increased with higher CC-BA content. Calorimetry results highlighted CPII-05 and CPII-15 as thermally satisfactory, indicating accelerated hydration kinetics. Air content decreased with CC-BA addition, suggesting a filler effect. After 28 days, mechanical strength remained favorable up to CPII-15. Water absorption and void index increased with 20–25% CC-BA, while lower contents showed comparable or improved values relative to CPII-00. Microstructural analysis, particularly via micro-computed tomography (μ-CT), confirmed the filler effects of CC-BA, enhancing performance up to CPII-15. Overall, CPII-10 demonstrated the most promising balance of properties, with CPII-15 also suitable for the proposed applications.
Influence of 1% recycled PET fiber on the fracture behavior of recycled aggregate concrete beams Ana Carolina Morato Teixeira, Niander Aguiar Cerqueira Revista Materia, 2026 This study evaluates the fracture behavior of concrete produced with recycled coarse aggregate and reinforced with 1% by volume of fibers PET. The experimental program included three-point bending tests on notched beams, following the RILEM recommendations for determining fracture energy, critical stress intensity factor KIC, and critical crack tip opening displacement (CTODC). The adopted methodology allows a detailed analysis of the material response under cyclic loading. The results indicated a 36.67% increase in fractured energy, rising from 95.05 N/m in reference concrete to 129.91 N/m in fiber-reinforced concrete. In addition, KIC increased from 1.38 to 1.59 MPa · m1/2, corresponding to a 15.22% gain, while CTODC rose from 0.0055 to 0.0079 mm, equivalent to 43.64%. Although the reference beams exhibited higher peak load, fiber incorporation improved the post-cracking behavior, with greater energy dissipation and more controlled crack propagation. These findings show that recycled PET fibers enhance concrete toughness and ductility, even with recycled coarse aggregates. Practically, this improvement in post-cracking performance suggests longer service life and greater safety for structural elements. Thus, the proposed mixture is a technically viable and environmentally sustainable alternative for structural applications using recycled materials.