Influence of Environmental Conditions and Application of Cleaning Methods Against Biodeterioration of Marble Monuments

Abstract

The aim of this paper is the study of the effect of environmental factors on the deterioration of marble monuments and the selection of a suitable and effective cleaning method. One of the main deterioration problems of the monuments is biodeterioration. It was obvious the presence of thick layers of biological patina, covering all almost surfaces of these. The growth of microorganisms, bacteria and plants is enhanced from the particular environmental conditions, that combine increased moisture, insolation and temperature, an area full of plants and trees and can cause extensive chemical and mechanical decay of the monuments. The growth of microorganisms, bacteria, plants and lichens was observed and determined. The influence of specific weathering agents and factors to the behavior of the materials was examined. The chemical composition of bulk precipitation and also the physicochemical characteristics of the surface and underground water were investigated. The environmental conditions and the growth of physical microorgamisms on the surface of the materials led to loss of the structural cohesion and the surface instability of the building materials. A series of various mechanical and chemical cleaning methods were tested in the laboratory containing the use of distilled water, microsandblast, organic solvents, absorbing clays, NH4HCO3 solution, biocides (desogen, hydrogen peroxide). In situ tests were carried out with satisfactory results in the monuments when a method of combination of hydrogen peroxide solutions, EDTA, NH4HCO3 solution and organic solvent was applied in various steps on the monument surface.