STRUCTURAL ANALYSIS OF WOOD BEAMS BY NON-DESTRUCTIVE METHODS IN RESTORATION WORKS OF THE CATHEDRAL OF MORELIA, MEXICO

[摘要] In the ceiling framework of the capitular hall of the Cathedral of Morelia, the overall state of the beams of the ceiling framework of the capitular hall of the Cathedral of Morelia was diagnosed as deplorable, for which a replacement was put underway for more recently sawed beams. The focus of this investigation was to determine the humidity content of the wood, its density, the wave velocity, the dynamic modulus and the quality factor of a sample of five new beams. These parameters were compared to the medium of five old beams. For the density, wave velocity, dynamic modulus and rigidness, there were no differences found between the old and new beams. The results suggest that the mechanical and physical properties of the new wood beams are equivalent to those of the older ones. Consequently, the strategy of substituting old and deteriorated wood beams for recently sawed ones was successful and complies with the requirements of the International Council of Monuments and Sites as referred to in the principles for the preservation of historical wooden structures.