In-plane and out-of-plane seismic vulnerability assessment of an ancient colonnade in the archaeological site of Pompeii (Italy)

The paper presents the results of an investigation carried out about the construction technique, the mechanical behaviour and the seismic response of some selected masonry remains in the archaeological site of Pompeii. In particular, the portion of the ancient colonnade dating back to the 1st century BC and located to the east of the civil forum of Pompeii is studied. Since this colonnade is a classic example of a rigid-block structure, its seismic vulnerability level is assessed performing a rigid-block model through the computer program BrickWORK, a tool developed by the authors. In-plane and out-of-plane non-linear analyses are carried out, considering both the horizontal uniform and the linear lateral load pattern to simulate the actions of an earthquake. In each analyzed case, the vulnerability level is assessed by detecting the collapse mechanism and the spectral acceleration of activation. Collapse mechanisms are detected by the program and graphically shown through its visual user interface. Furthermore, the influence of the joint inclination on the mechanical response of the structure is investigated considering various inclination angles of the joints between the stones of the lintel.