Application and limits of weathering simulation on the maintenance of monuments

The maintenance and repair of ancient buildings and monuments is one of the most important tasks in preserving cultural heritage. These buildings are often destroyed by being subjected to long-term stresses caused by air pollution, high humidity, and/or the lack of repair work. Before carrying out repair work or changing climatic conditions at monuments it is absolutely necessary to test the suitability of the renovation campaign. One possibility is testing the suitability for use by simulation methods. The advantages of simulation methods are the short duration of the test procedures and the alternative testing of different measures before the actual work is carried out on the monument building. On the one hand weathering simulations can be carried out in twin-climate chambers with climatic impacts generating indoor and outdoor climates. On the other hand numerical simulation using computers can forecast moisture and temperature behaviour of structural elements. Additionally it is necessary to use suitable measurement methods for detecting the impacts, e.g. thermography, modern optical surface inspection methods or measurements of material moisture content in high resolution. The proposal illustrates different examples of simulation techniques.