Combined Laser Surveying and Finite Element Modeling for The Structural Assessment of Masonry Structures at the Hierapolis Outer Bath Complex

The outer bath remains at the complex of Hierapolis (Pamukkale, Turkey) are particularly in danger due to the damage they have accumulated in the past Centuries because of several seismic events [1]. In order to assess the present condition and to properly formulate hypotheses for the interventions, a combined laser surveying and finite element modelling procedure has been set up. In the present paper, the results of the laser survey are firstly described. The procedure is based on the use of Focus3D Faro® three-dimensional laser scanner for the acquisition, and Scene® software for the data management. The obtained point clouds have been analysed with the software 3DReshaper® to extrapolate the main features of the geometry. As a result of this first stage of the analysis, detailed plans and sections of the structure have been obtained, from which the geometry of almost each masonry block could be explicitly accounted for. In the second stage of the analysis, the geometry was converted to be used as the input of a finite element program. The finite element code iDiana® by TNO (The Netherlands) was used for the structural analysis thanks to its ability in representing the behaviour of the blocks interfaces. Different constitutive laws can be assigned to both the continuum blocks and the interfaces. In the present study, for the sake of simplicity, the blocks are considered linear elastic, while the interface have a combined constitutive law accounting for cracking-shear-crushing behaviour [2]. A detailed two-dimensional model of one of the main front has been built up, and several analyses performed starting from simple linear static analysis under the effect of dead loads, up to non-linear analyses accounting also for seismic effects. In particular, the in plane behaviour of the front subjected to equivalent seis- mic acceleration was analysed with a pushover analysis. Different possible interventions have been modelled, providing useful suggestion for the eventual adoption of any of them.