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Seismic structural reliability is typically quantified in terms of the mean annual number of earthquakes causing the structure of interest to exceed, in a single shock, a performance threshold (conventionally referred to as failure). This requires the definition of a hazard curve, which probabilistically characterizes the ground motion intensity at the site of interest, and a fragility curve that provides the failure probability given the ground shaking intensity. Recently, research attempted to account for the possible failure due to subsequent earthquakes, that is, damage accumulation, an issue neglected in the mentioned (classical) approach. To this aim, the so-called state-dependent fragility functions are often used. They provide the probability of getting any intermediate damage condition as a function of the intensity of the earthquake and the damage state of the structure. Fragility functions can also be developed for structural typologies (i.e., matching a given taxonomy), rather than individual structures, for large-scale seismic risk assessment. The presented study developed, in a reproducible manner, state-dependent fragility functions for Italian building typologies derived via back-to-back incremental dynamic analyses of equivalent-single-degree-of-freedom systems. The latter are taken from the outcomes of the SERA project (Seismology and Earthquake Engineering Research Infrastructure Alliance for Europe) and refer to existing reinforced concrete and masonry residential buildings. • Methodology for large-scale risk assessment accounting for seismic damage accumulation. • Parametric state-dependent fragility functions for Italian residential building typologies. • Shown results are one of the outputs of the RISE (Real-time Earthquake Risk Reduction for a Resilient Europe) project. • Influence of damage accumulation on the structural reliability assessment over time for some cases. [ABSTRACT FROM AUTHOR]

Historic constructions are common in Europe, but natural hazards can produce significant damage. Shear reinforcement of historic walls, especially in seismic areas, is often necessary and new retrofitting methods have recently been proposed to restore or increase the lateral capacity of shear walls. In this paper the combined use of cross-laminated timber panels and steel wire ropes is proposed to reinforce rubble stone masonry walls with the aim of increasing their lateral load capacity while improving the energy performance of the building envelope. An experimental programme was carried out in the laboratory to assess the mechanical effectiveness of this retrofitting method. The results from a series of quasi-static cyclic shear tests are presented. The test programmes are described and the analysis of test results is included. The potential benefits and limitations regarding the use of the proposed combined method for reinforcing masonry structures are discussed, with an emphasis on the in-plane behaviour. [ABSTRACT FROM AUTHOR]

The behaviour of reinforced masonry structures, especially when reinforcement is provided to enhance the mechanical properties, i.e. different strength types or resistance of masonry, is still not completely investigated or thoroughly understood. A significant lack of knowledge can be observed in many areas, especially in Europe. As a result of this situation, the Commission W023 - Wall Structures of the International Council for Research and Innovation in Building and Construction (CIB) set up a Working Group (WG5) - Reinforced and Prestressed Masonry a few years ago, of which the authors are convenors. The first task of the WG5 is to produce a State of the Art document covering reinforced masonry applications in order to identify topics for future research and development. This document will serve as a contribution for the revision of European Structural Masonry Code EN 1996-1-1:2005 (Eurocode 6) [1], which is planned to be done between 2015 and 2018. It was agreed at the last W023 Commission Meeting held in Eindhoven in October 2013 that the preparation of the State of the Art document should cover the specific experience and problems connected with reinforced and prestressed masonry structures under static and dynamic/seismic loading, also outside Europe. The process of preparing such a report is now underway and the following article describes the planned scope of the document. [ABSTRACT FROM AUTHOR]

Plain masonry has been used as a construction material since very old age. Reinforced brick masonry is a relatively new type of construction with specific design procedures and construction techniques. Building codes have made provisions for reinforced brick masonry since 1953. Codes selected for this study includes Uniform Building Code 1997(UBC), Euro code 2005 (EC-05), Turkish Code 1998 (TK-98) and National Building code of India 2005(NBCI-05) along with building code of Pakistan 2007 (BCP-07). The materials involved in reinforced brick masonry include bricks, mortar and reinforcement. The quality and size of bricks are different in different regions. The codes under consideration used different approach for reinforced brick masonry design. Few codes design, brick masonry using allowable stress design or empirical methods and others use ultimate strength design method. UBC-97 is the only code that designs reinforced brick masonry on empirical, allowable and ultimate strength design approach. UBC-97 was also found to be more economical than the other codes. This study also revealed that BCP-07 is based on UBC-97 and it may be revised to account for the construction practices and quality of masonry manufactured in Pakistan. [ABSTRACT FROM AUTHOR]