PRODUCTION AND ANALYSIS OF PERMANENT DEFORMATION OF ARTIFICIAL AGGREGATES FROM CALCINED CLAY CONTAINING MINING WASTE CONTAINING MINING WASTELisley Madeira Coelho1; Murilo Miguel Narciso, Sr1; Albeds Mesquita Povuação1; Ary Machado De Azevedo1; Pedro Henrique Poubel Mendonça Da Silveira1; Sergio Monteiro1; Antônio Carlos Rodrigues Guimarães, Sr.1
1Military Institute of Engineering, Rio de Janeiro, BrazilPAPER: 36/Composite/Regular (Oral) OS
SCHEDULED: 16:45/Wed. 19 Nov. 2025/Dusit 1
ABSTRACT:The shortage of natural aggregates in tropical regions has driven the development of alternative materials for road infrastructure applications. Among these, artificial aggregates produced through clay calcination have been investigated for their mechanical properties and pozzolanic reactivity potential (Cabral, 2008; da Silva et al., 2015; Friber et al., 2023). This study proposes the production of artificial aggregates from soil–waste mixtures, incorporating a clay-rich mining sludge, aiming to add value to mineral waste and reduce reliance on conventional materials.
The formulations were defined based on preliminary mineralogical analyses using X-ray diffraction (XRD) and scanning electron microscopy (SEM), with the objective of identifying the phases formed and microstructural changes induced by calcination (Monteiro et al., 2004; Pinheiro et al., 2023). The calcination temperature was selected to maximize the formation of amorphous cementitious phases. After calcination, the aggregates were used to mold cylindrical specimens using split molds, which were then subjected to repeated load triaxial tests to determine the permanent deformation a key parameter for assessing the mechanical performance of materials used in pavement base and subbase layers.
Initial results indicated that the artificial aggregate exhibits elastic behavior compatible with that of traditional pavement materials, reinforcing its potential as a technically and environmentally sustainable solution.
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