Physical and chemical characterization of historical masonry materials from Yucatan churches, Mexico

Abstract

Yucatan churches are an important built heritage in Mexico from sixteenth to eighteenth centuries. They are massive structures, where loadbearing stone masonry walls and vaults represent the main structural elements. This paper presents the results of the experimental campaign carried out on stone units and mortars selected from six partially collapsed churches. The stone samples were collected from walls and vaults. Additionally, mortars samples were collected from joints and finishing mortars. The physical characterization was performed according to European standards and key physical properties were obtained, name-ly density (ρb), porosity (Po) and water absorption by immersion (Ab). Reasonable correla-tion between variables was achieved. The chemical characterization was carried out through X-ray diffraction test (XRD). A chemical composition of calcium carbonates showed almost all stones samples, only two stone samples show secondary compound as Magnesian and Ankerite. The mortars show a chemical composition mainly of calcium carbonates and few cases show additional traces of clays.XRD measurements were performed at LANNBIO Cinvestav Mérida, under support from projects FOMIX-Yucatán 2008-108160 CONACYT LAB-2009-01-123913, 188345, 204822, 292692, 294643. Technical help is acknowledged to MSc. D. Aguilar and Ing. Daniel Poot”. The physical measurements were carried out at Laboratories of Construction and the Laboratory of Mechanics of Materials of the Faculty of Engineering of the Autonomous University of Yucatan. Technical help is acknowledged to Ing. F. Duarte, Ing. A. Martinez, Ing. R. Valencia, Ing. J. Cab and M.I. M. Chi. The authors wish to express their gratitude to the National Institute of Anthropology and History of Mexico (INAH) and the Commission of Ecclesiastical Properties and Sacred Art of the Archdiocese of Yucatan for all collaboration and suppor