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BIM methodologies and technologies find their place in structural engineering issues that deals with huge amount of data to properly gather and organize in order to streamline their retrieval. Current research is interested in investigating new BIM processes and approaches that can add benefits to structural engineering from different perspectives. However, information exchanges constitute a serious obstacle that open formats are trying to solve. This paper provides an overview of trends in using BIM methodologies in structural engineering during the last decade and deepens its latest applications and future likely developments, especially when combined with novel emerging technologies. © Fédération Internationale du Béton – International Federation for Structural Concrete.

Damage detection and assessment are key objectives of structural health monitoring. Inspections timing and results accuracy represent crucial aspects to properly assess the integrity of a structural system over time. The goal of this work consists in the development of an automated damage classification methodology based on machine learning, that is able to process sampled measurements of the dynamic structural response as input and provide a quantitative health assessment of the structure as output. The methodology is validated on a broad set of examples, including both numerical simulations and data recorded on real structures, evidencing high accuracy across all instances. Moreover, the computational experiments show consistency in the assessment of location and severity of the damages even in presence of additive white Gaussian noise.

Passive structural systems installed at the foundation level of existing buildings are a common solution to protect them against earthquakes. However, installation procedures are expensive and not always feasible, as for instance in the case of valuable buildings. In this paper, an alternative and innovative solution for the seismic isolation of existing buildings is presented: the idea is to create a barrier buried in the ground, made of grouted soil, able to properly filter the seismic input. This can be obtained by using soft grouts, having a dynamic impedance much lower than that of the natural soil. Previous papers published by some of the authors have shown that the soft barrier can be effective, tending to filter the high frequency components of the amplitude spectrum without modifying in a significant way the low frequency ones. This implies that ground treatment has to be tuned on the characteristics of the structure to be protected, above all its natural frequencies. In this paper, the case of a simple four-story building with a reinforced concrete structure and a shallow slab foundation resting on a sandy soil is considered. Analyses are carried out with the commercial codes PLAXIS 2D and SAP2000, considering a fixed base, the foundation on the soil and finally the existence of a soft barrier. It is shown that the natural frequencies of the structure are largely influenced by the characteristics of the subsoil. Once the soft barrier is created in the soil, a sharp decrease of the first natural frequency of the structure is obtained, similarly to the effect of traditional isolators. In the paper, dynamic analyses with different input motions are considered. It is confirmed that the soft barrier, whose dynamic impedance was assigned considering some experimental results obtained by the authors and previously published, is able to filter higher frequencies, while it has a minimum or even nil effect in the case of low frequency input signals.

The loss estimation analysis of a structure subjected to seismic hazard is used to determine the expected costs to be sustained due to seismic damages in the structure life-time. In this work a procedure is developed and applied to an existing structure in L'Aquila, Italy damaged by the April 2009 earthquake, in its as-built and retrofitted configuration. The method consists in a seismic hazard analysis, damage analysis and loss estimation. The loss evaluation is performed considering the probabilistic distribution of construction costs in Italy. The structure is divided into eight assemblies: foundations, external partitions, doors/windows, plumbing system, structural elements elevation, floors, retrofit system. Four limit state for each assembly are considered {very light, light, moderate, severe}. Then, the procedure is reiterated for different increasing retrofitted configurations of the structure, generating increasing initial costs, but a reduction of the expected costs. The results are elaborated in terms of actualized expected costs to face during the lifetime of the structure and marginal cost of the retrofit interventions.