In urban areas, engineers often need to assess tunnelling-induced displacements of piled structures and the resulting potential for damage. This paper presents an elastic study of tunnel-pile-structure interaction through Winkler-based Two-Stage Analysis Methods (TSAMs), focusing on structural displacements resulting from tunnel excavation beneath piled frames or simple equivalent beams. Comparison of results with 3D finite element analyses shows that the simple TSAM models are able to provide a good assessment of tunnelling-induced building displacements. Parametric analyses highlight the role of tunnel-pile interaction and the superstructure (stiffness, configuration, and pile-structure connections) in the global response of the tunnel-soil-building system. In particular, the effect that key parameters have on deflection ratios and horizontal strains are investigated. Results illustrate how piled foundations increase the risk of structural damage compared to shallow foundations, whereas structural stiffness can reduce building deformations. Flexural deformations are predominately induced by tunnel excavations beneath piles whereas horizontal strains at the ground level are negligible when a continuous foundation is included. Furthermore, it is illustrated that results based on buildings modelled as equivalent beams can differ considerably compared to when they are modelled as framed structures. Simple design charts are provided to estimate horizontal strains and deflection ratio modification factors based on newly defined relative axial and bending stiffness parameters which account for the presence of the piles

This paper analyses the observational damage from post-earthquake investigations carried out on churches of the Marche Region struck by the 2016 Central Italy seismic sequence. Such seismic activity seriously damaged many historical buildings and particularly churches, due to their intrinsic inability to develop an efficient box-like resisting mechanism. After the mainshocks, teams of structural engineers were involved in the assessment of damage of churches and in the evaluation of their usability. Collected data are processed in this work to give insight into the occurred damage and to evaluate the vulnerability of the religious buildings of the Region. To this purpose, an architectural background is firstly provided to allow for a classification of the sample, then, the most recurring damage mechanisms are identified, and a global damage index of each church is computed. The distribution of the damage over the Region is commented, as a function of the macro-seismic intensity and other important factors affecting the seismic response. Finally, the overall damage of the sample is compared to that estimated through empirical models available in the literature and comparisons with the results of previous studies are provided.