查看文章

The work presented in this thesis has been developed at the Department of Civil Engineering of University of Minho, Portugal, and at the Department of Structural Engineering of Polytechnic of Milan, Italy. Modern practice in conservation of historical buildings is a complex task that requires a deep and careful diagnosis. Preliminary investigation is essential in order to intervene correctly and successfully. The objectives of such investigation are to gather adequate information about the building or structure, and to evaluate the mechanical properties of materials, being the latter a difficult task due to the complexity of old materials and historic fabrics. Necessary information is the state of conservation, the extent of damages, the presence of moisture, the geometry and hidden features such as voids, cracks and detachments. In order to increase the knowledge about ancient building materials, characterization of clay brick from historic monuments in Portugal was performed in bricks from the 12th to 19th century, collected from six monasteries. The results showed a large scatter, and the main characteristics are high porosity, high suction and low compressive strength. Chemical composition indicates that bricks are not prepared with the same raw materials as old clay artefacts. The restrictions to remove material for mechanical sampling or to carry out destructive tests are very large. Therefore, in the last decades, the use of non-destructive testing techniques for investigation and diagnosis of historical buildings has increased significantly. However, the evaluation of the compressive strength and other mechanical properties of historic materials using such …