ABSTRACT

Santa Ana Church (1.266) is one of the main milestones in the heritage of Seville for being the first Christian church built outside the city walls and on the other side of the river, after the Reconquest of the city. The singularity of the geometry of its vaults together with its execution in brick and stone masonry make complex to determine the properties of materials. The impossibility of characterizing these materials by means of destructive tests leads to the application of other technologies that allow us to approach the behavior of the numerical models to the reality performed.

This paper tries to adjust the mechanical properties of the materials that constitute the structure of the church of Santa Ana, which are brick and stone masonry, through analyzing its dynamic behavior with environmental vibration (EVT) techniques and modal operations analysis (OMA). After having carried the campaign out using the methods of modal identification in the stochastic subspace and in the frequency domain, four vibration modes are obtained that adjust to the modal behavior of the current building, within a frequency range between 2 and 4 Hz.

This method adjusts a series of imperfections that the numerical model does not contemplate. Usually, the geometry has many ornaments that can modify the structural behavior. The boundary conditions are other properties very difficult to evaluate in a heritage building or another pathologies as cracking or humidity. OMA let us to approach the mechanicals parameters of a numerical model to adjust the behavior to the real structure

Initially, and thanks to new techniques such as photogrammetry, it has been possible to develop a finite element model (FEM) to analyze the structure with theoretical parameters of its materials.

With this model and through the environmental vibration technical it is possible to conclude with the suitability of the application of a non-destructive method in heritage buildings to extract the mechanical properties of the materials that constitute its structure through its dynamic behavior.