Durability Improvement of Ancient Bricks by Cementation of Porous Media
Abstract:The physicomechanical properties of historic bricks in Toledo (Spain) that have undergone a time-dependent self-healing by natural weathering processes have been improved by porous infill with gypsum, ettringite, and, mainly, calcite. Both these bricks and their experimental replica bricks, made from the original calcareous clays fired at the appropriate historical temperatures (700°–900°C), have been analyzed by X-ray diffraction, optical and scanning electron microscopy, mercury intrusion porosimetry, and ultrasound velocities to compare pore structure and strength evolution by mineral cementation. The resultant microstructure and mineral fillings depend on the brick calcareous composition and firing temperature, the brick location environment, burial, indoor or outdoor walls, the lime-based joint mortars and coat plasters, and infiltration waters.
Document Type: Research Article
Affiliations: 1: Centro Tecnologico, Departamento de Materiales de Construccion (AITEMIN), 45007, Toledo, Spain 2: Laboratorio de Petrologia Aplicada, Unidad Asociada CSIC-Universidad de Alicante, Departamento de CC. de la Tierra y del Medio Ambiente, 03080 Alicante, Spain 3: Museo Nacional de Ciencias Naturales (CSIC), 28006 Madrid, Spain
Publication date: 2005-09-01