Structural Health Monitoring of an Existing Complex Structure: From Experimental Data to Model Updating

The paper presents a study on the dynamic monitoring of a complex building in the port area of Bari, Southern Italy. The building consists of two mixed structures (masonry-reinforced concrete) at different heights, connected by a reinforced concrete spiral staircase. The aim of the study was to assess the structural behaviour of the building during excavation activities in the port, which lasted for about 3 months and were performed by a dredger. An experimental program was conducted, recording accelerations from biaxial and triaxial accelerometers at strategic points in the building. The experimental results were used for operational modal analysis to identify the main frequencies of the structure. After, a model updating procedure was carried out using structural analysis software. The main object of numerical updating consisted in finding some unknown parameters: (a) the mechanical properties of the masonry panels; (b) the mechanical properties of the reinforced concrete members; (c) the boundary conditions and the constraint degrees that characterize the numerical model. All the steps performed to fit the experimental and numerical results are reported in the paper, showing original and interesting results that are discussed in a broader view, especially when referring to structural health monitoring of complex structures.