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The problem of reducing the seismic risk for art objects, that are the objects generally contained within Museums, is of great interest. The first studies were performed in Japan and were successively organized in a general framework by a research program performed at Southern California University and sponsored by the Getty Museum at Malibu, California. In these papers and in the following Italian studies, the theoretical models for the problem concerning vases and statues are based on the dynamic behavior of rigid blocks and have been deeply developed. Unfortunately, because of the great lack of experimental data, determinant parameters for the problem characterization (like the friction between two superimposed blocks or between the art object and the support plane) are often assumed without reference to real values derived from laboratory tests. This paper presents the results of a research program containing the experimental determination of the friction coefficient between the art object and the support (by means of a testing apparatus on purpose realized) together with dynamic tests performed on simple-shaped objects made of different materials. The dynamic tests were performed using an unidirectional shaking table and different supporting surfaces, so that the influence of different friction coefficients has been analyzed. © 2014 Springer Science+Business Media Dordrecht

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A large part of the world’s architectural heritage is composed of masonry buildings located in seismic areas, and its vulnerability has been shown by the damage caused by the last earthquakes. Meeting the safety demands of cultural heritage buildings according to the performance-based seismic codes requires a deep knowledge of the mechanical properties of material components. Traditional mortars are among these. However, significant samples of structural mortars cannot be taken from existing masonry walls to perform mechanical tests, but tests can, alternatively, be conducted on samples realized according to traditional instructions for composition. Based on a historical study of mix proportions, this paper presents the results of a mechanical test campaign of traditional mortars. The samples were obtained combining lime and pozzolan according to the proportions derived from ancient treatises. The laboratory tests were performed taking into account three different types of limes, and a discussion involving the results presented in the literature is provided. Besides the contribution to fulfilling the lack of knowledge about the mechanical properties of traditional lime mortars, the test results are good references for on-site preparation of mortars for use in restoration. There is a focus on natural pozzolanic lime mortars, widely used in the Neapolitan area and, in general, in the whole Italian territory.

The assessment of the modulus of elasticity and compressive strength of masonry is a fundamental step in the seismic analysis of existing structures. In this paper, the representativeness of the values provided by flat-jack tests for tuff masonry is investigated through the analysis of a very large and homogeneous number of tests (635 double flat-jack tests). Data relate to existing buildings belonging to different historical and/or construction periods, located throughout the Campania region (Italy) in areas with different peculiarities. Results are compared with the values provided by Italian Building Code, containing ranges of the elastic modulus and compressive strength for different types of masonry. The values of flat-jack tests are then compared with laboratory tests available in the literature. Finally, comparisons with code equations are performed. It is shown that equations correlating the masonry compressive strength with the modulus of elasticity provide values larger than the mean of experimental data, whereas the equations correlating the masonry compressive strength with the strength of components provide lower values, if block and mortar strengths are varied within a probable and wide range.