Some Mediterranean seismic codes consider wide-beam reinforced concrete moment resisting frames (WBF) as horizontal load carrying systems that cannot guarantee high ductility performances.Conversely, Eurocode 8 allows High Ductility Class (DCH) design for such structural systems. Code prescriptions related to WBF are systematically investigated. In particular, lesson learnt for previous earthquakes, historical reasons, and experimental and numerical studies underpinning specific prescriptions on wide beams in worldwide seismic codes are discussed. Local and global ductility of WBF are then analytically investigated through (i) a parametric study on chord rotations of wide beams with respect to that of deep beams, and (ii) a spectral-based comparison with conventional reinforced concrete moment resisting frames (i.e., with deep beams). Results show that the set of prescriptions given by each modern seismic code provides sufficient ductility to WBF designed in DCH. In fact, global capacity of WBF relies more on the lateral stiffness of the frames and on the overstrength of columns rather than on the local ductility of wide beams, which is systematically lower with respect to that of deep beams.

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: Tía Cayetana’s inn is an old road motel erected at the end of the 19th Century at Torrebaja (Spain). This inn was built using local vernacular construction techniques, i.e., with a structure made of gypsum pillars, and floors built with beams and gypsum vaulting. The facades and interior walls were built in a combination of stone masonry for the basement and either rammed earth walls or thin stone slabs wall for the upper parts. The local city hall bought the building and entrusted the rehabilitation of the building to the authors of this paper for its future use as a four-star hotel, i.e., the same use for the building more than one hundred years after its original completion. The authors of this paper made an exhaustive study of the fabrics of this building, its construction, material pathologies… and, taking into account these data, elaborated the restoration project for the building that previewed the use of the same original structure made of gypsum to be reinforced with compatible techniques. This article introduces the analysis of the local constructive technique based on the general use of gypsum for the vertical and horizontal structure, the bonding of fabrics and the external and internal coatings, and their structural performance. It also describes the reasoning that took the authors to respect the existing structure in its original condition and the reinforcements made mainly at the foundations and at the floors to assume the new weight of a four-star hotel.

Abstract. The structural design methods development nowadays allows including the effects of geometric and mechanical nonlinearity of the materials in the analysis itself. The resolution through matrixes methods frequently involves an incremental treatment for load application and a tangent stiffness matrix that bears in mind the nonlinearity. The present paper shows a procedure to evaluate the bar stiffness considering mechanical nonlinearity of materials. For structures of reinforced concrete formed by two materials where each of them has a resistant behavior so different from the other, its appropriated evaluation is, at the same time, necessary and especially complex. The iterative process exposed here provides the equilibrium position of the section to the general case of axial force and biaxial bending taking into account the nonlinear constituent relationships of materials. Once the equilibrium is reached, the relationship between the biaxial moment and the curvature allows the section stiffness module to be derived, from which the bar stiffness will be determined. As an application of the exposed procedure, the iterative process of the equilibrium research in a section of reinforced concrete is showed. At the moment-curvature diagram can be observed the stiffness progressive decreasing as biaxial bending moments are increasing, because of materials nonlinearity stresses and strains and the section inertia reduction produced by concrete cracking.