RESPONSE OF POROUS BUILDING STONES TO ACID DEPOSITION

This work investigates the response of porous carbonate building stone s to acid deposition during a short-term exposure period and the chara cteristics that influence their reactivity and/or durability. Several carbonate porous stones used in Spanish and English monuments were exp osed to English urban and suburban environments. In each location they were both exposed to and sheltered from rainfall. Monthly analyses we re carried out in order to investigate any possible sign of reaction. In addition, some physical properties of the stones relating to transf er of moisture were determined. Results indicate that the reactivity o f these stones is relatively high, significant signs of reaction were detected within only a few months of exposure. Under the same environm ental conditions, the response and reactivity of porous carbonate ston es are determined by their petrophysical characteristics.