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Since the 1980s, calcium silicate element masonry has been commonly used in Dutch buildings, and vertical continuous joints have been usually located at the corner of perpendicular walls. Since the shear failure of these joints may significantly reduce the seismic performance of the flanged wall and therefore of the entire building, the assumption of rigid connection may be inaccurate, unlike for the traditional interlocking of bricks in running bond textures. In this paper, analytical and numerical approaches to study the failure of vertical joints in the seismic assessment of URM buildings are presented. The first part of the work focuses on two different numerical models to study the nonlinear behaviour of the vertical connection; the related critical numerical issues are then discussed. The second part introduces an analytical method able to estimate the lateral force–displacement curve of a flanged wall, which considers the possible failure of the connection. In particular, the method is derived from the section analysis approach developed for controlled rocking deformable systems. The comparison between the numerical simulations and the analytical method proves the capacity of the latter to provide a quick but sufficiently accurate estimate of the force–displacement curve of a URM U-Shaped wall. [ABSTRACT FROM AUTHOR]

An increasing interest in the development of high-performance seismic resisting systems based on posttensioned, jointed ductile connections has been observed in the last decade. The extensive experimental and numerical studies carried out under the PRESSS program developed efficient alternative solutions for seismic resisting frame or wall systems in precast concrete building construction, typically referred to as jointed ductile connections. Low structural damage and self-centering behavior, leading to negligible residual displacements after an earthquake event, were recognized to be the main features of such systems. Recently, the extension and application of similar technology and seismic design methodologies to bridge piers and systems have been proposed in the literature as a viable and promising alternative to traditional cast-in situ or precast construction. However, a broad acceptance of these solutions in the bridge design and construction industry has yet to be observed. Valid justifications can be found in the lack of official guidelines for design and construction detailing as well as in the general apparent complexity of the design procedure and analytical models presented by the scientific community. In this contribution, confirmations of the unique design flexibility, the ease of construction, and the high seismic performance of jointed ductile hybrid systems, combining recentering and dissipation capabilities, are presented. After a presentation of simple design methodologies and modeling aspects herein adopted to fully control the seismic response of these systems, the experimental results of quasistatic cyclic tests on five 1:3 scaled, bridge pier specimens are reported and discussed. Four alternative hybrid configurations are implemented by varying the ratio between the posttensioning steel and the internal mild steel as well as the initial posttensioning load. Lower levels of damage and negligible residual/permanent deformations are observed in the hybrid solutions when compared to the experimental response of the benchmark specimen, representing a typical monolithic (cast-in situ) ductile solution. In addition, the efficiency of the simple analytical procedure adopted for design and modeling is further validated. DOI: 10.1061/(ASCE)0733-9445(2007) 133:11(1648) CE Database subject headings: Bridges, piers; Post tensioning; Energy; Seismic tests; Mathematical models; Model verification; Connections.