Dynamic identification of the tower of the provincial administration building, Bari, Italy

The reinforced concrete tower of the provincial administration building of Bari, Italy, dates back to the thirties of the 20th century, and it is about 60 meters tall. The building is located close to the centre of the city, near to a large road that follows the seaside, where the environmental excitations due to wind and traffic are expected to cause non-negligible vibrations of the tower. The paper, written in the framework of a research project on the dynamic identification of civil structures, reports some preliminary results on an experimental campaign devoted to characterise the tower using not only environmental loads, but also the structural vibrations induced by the explosions used to demolish two nearby buildings. The vibrations induced on the tower both by environmental and explosion loads have been recorded by a set of accelerometers installed at different points of the tower. Although the experimental results have to be considered as very preliminary, the comparison between recorded natural frequencies of the tower and dynamical characteristics evaluated by means of a FEM model, confirm the possibility of using environmental loads for monitoring purposes