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Many studies in literature proved the excellent hysteretic behaviour of metal shear panels that exhibited large ductility and energy dissipation capacity under cyclic loading. The lack of standardized design procedures has seriously limited their use for seismic retrofitting of RC buildings. This paper develops a passive control design method for RC structures added with metal shear panels. The simplified method is based on a single-degree-of-freedom idealization and an optimum equivalent stiffness distribution to arrange the metal shear panels over the height of the building. The design method is validated through implementation in two different building cases. Its effectiveness is demonstrated through nonlinear dynamic analyses focusing on the effects of the cyclic behaviour of the metal shear panels. Many studies in literature proved the excellent hysteretic behaviour of metal shear panels that exhibited large ductility and energy dissipation capacity un-der cyclic loading. The lack of standardized design procedures has seriously limited their use for seismic retrofitting of RC buildings. This paper develops a passive control design method for RC structures added with metal shear panels. The simplified method is based on a single-degree-of-freedom ideali-zation and an optimum equivalent stiffness distribution to arrange the metal shear panels over the height of the building. The design method is validated through implementation in two different building cases. Its effectiveness is demonstrated through nonlinear dynamic analyses focusing on the effects of the cyclic behaviour of the metal shear panels.

A case study is presented in this paper dealing with a steel braced frame office building located in Southern Italy and designed for gravity loads only. The building, erected in the early ‘60s, is investigated to assess its behavior with regard to both seismic and progressive collapse performance. At the same time, some possible retrofit strategies are outlined. To this aim, the results of both linear and nonlinear static and dynamic analyses are presented and discussed considering different column removal scenarios. Then, an integrated design procedure involving both robustness and seismic safety is developed using steel-braced frames and mega-truss outriggers. In this context, both seismic and progressive collapse performances after retrofit are investigated.

A study on the seismic retrofit of RC buildings using hysteretic dissipative braces is presented in the paper. By following a displacement-based design procedure, a fully multimodal approach based on an adaptive version of the capacity spectrum method is followed. Then, a dual RC-damped brace system idealized as bilinear is considered thus accounting for the effects of frame-damped braces interaction. Finally, the optimal distribution of dampers is determined using an iterative procedure. The proposed method is validated using nonlinear static and dynamic analyses. The results have shown the effectiveness of the proposed procedure to address the main issues of seismic design of damped braces: effect of force demands to the frame due to the dampers, higher modes contribution and effect of soft story irregularities.

In order to prove the possibility to adopt effectively metal shear panels for practical applications and to define specific design methodology, a case study, related to the retrofitting of the hospital building of Scafati in Campania, is presented in this paper. Based on the results of previous full-scale tests on a real r.c. frame reinforced with pure aluminium shear panels, a design procedure has been implemented in order to define the optimal configuration of shear panels to be applied to improve the seismic performance of the building under consideration. Then, a parametrical study by means of dynamic analyses under different historical records has been developed taking into account different hypotheses of modeling for the RC structure. The obtained results allows to confirm the effectiveness of the proposed system, which is able to increase significantly the seismic performance of existing structure. In addition, the outcomes of the study provide interesting indications for design applications.

The occurrence of a pituitary adenoma located entirely outside the sella turcica, socalled ectopic adenoma, is extremely rare. We report a case of a non secreting-pituitary adenoma located above the diaphragma sellae, with no invasion into the sella turcica, confirmed at surgery. The tumor was initially treated unsuccessfully by operations via the transphenoidal route. After initial negative exploration by the transphenoidal route, the patient was successfully treated by an endoscopic endonasal transphenoidal approach extended to the tuberculum sellae and the posterior planum sphenoidale to access the suprasellar supraglandular region. A brief review of ectopic adenomas and a discussion of the preoperative diagnosis are presented.