131 documents found, page 1 of 14
Seismic fragility curves of rocking blocks: shaking table tests and numerical m...
Colombo, Carla; Vlachakis, Georgios; Savalle, Nathanaël; Giouvanidis, Anastasios I.; Mendes, N.; Lourenço, Paulo B.Unreinforced masonry structures are particularly vulnerable to seismic events. Their seismic vulnerability stems from the brittleness of the material and the insufficient connectivity with the neighbouring structural components. This results in the formation of local collapse mechanisms, whose dynamic motion can be resembled by a rocking block. Rocking motion constitutes a well-known, yet still challenging, pro...
Probabilistic framework for seismic performance assessment of a multi-span maso...
Cabanzo, Carlos; Mendes, N.; Akiyama, Mitsuyoshi; Lourenço, Paulo B.; Matos, José C.Extreme natural events, such as earthquakes, are unavoidable and have been identified as triggers of bridge failure. In Portugal, MABs with larger spans and thinner piers were built in the later years of the railway expansion and are expected to continue operating as a crucial part of the railway network without elevated maintenance costs. Large MABs have been the subject of research related to probabilistic an...
The seismic performance of earthen historical buildings in seismic-prone region...
Mora, Elesban Nochebuena; Mendes, N.; Salvalaggio, Matteo; Lourenço, Paulo B.Adobe churches are representative of Andean architectural heritage, yet their structural vulnerability to seismic events remains a significant concern. This study evaluates the seismic performance of the 17th-century Church of Santo Tomás de Aquino in Rondocan, Peru, an adobe building that underwent conservation work in the late 1990s. The assessment combines in situ inspections and experimental testing with ad...
Shake table tests on the out-of-plane two-way response of a U-shape masonry str...
Vecchio, Dario; Ilyas, B.; Mendes, N.; Lourenço, Paulo B.Unreinforced masonry (URM) structures are vulnerable to strong earthquakes due to their limited resistance to dynamic actions. These vulnerabilities often lead to failure or collapse, with out-of-plane mechanisms posing a major threat for existing structures lacking integral (or box-like) behaviour. Despite uncertainties within structural components, the response is usually governed by macro-elements, such as t...
Insights on the experimental dynamic behaviour and energy losses of rocking blo...
Colombo, C.; Vlachakis, G.; Giouvanidis, A. I.; Savalle, N.; Mendes, N.; Lourenço, Paulo B.This study focuses on the experimental response of free-standing hard limestone blocks under free vibration. The campaign includes 120 tests, varying the block’s height-to-width ratio and considering multiple specimens to account for the aleatoric variability of the phenomenon. The study offers full reconstruction of the three-dimensional free-rocking motion, giving insights into the influence of unintended geo...
Shake table testing of U-shape masonry structures: Out-of-plane response to var...
Ilyas, B.; Vecchio, D.; Mendes, N.; Lourenço, Paulo B.Historical structures consisting of unreinforced masonry (URM) are highly vulnerable to seismic forces, with out-of-plane failure mechanism being a primary concern. This vulnerability has often resulted in the collapses of the masonry structures during seismic events. Masonry walls tend to rock and overturn in the out-of-plane direction due to the dynamic loading, leading to either one-way or two-way bending. T...
Methodologies for assessing the structural integrity of historic masonry domes ...
Cintra, Danielli Cristina Borelli; Roehl, Deane de Mesquita; Filho, Emil de Souza Sánchez; Lourenço, Paulo B.; Mendes, N.Modern non-destructive investigation techniques and computational tools for nonlinear analysis allow understanding the structural behavior and damage of existing buildings, aiming at the least possible extent of intervention. Careful and minimal intervention is essential to preserve the authenticity of the built cultural heritage. An investigation with a historical, experimental, and numerical approach was carr...
Modelling of the dynamic response of a full-scale masonry groin vault: unstreng...
Bianchini, Nicoletta; Mendes, N.; Lourenço, Paulo B.; Calderini, ChiaraThis article presents the results of the numerical simulations of a dynamic experimental campaign on the shaking table. The specimen is a full-scale masonry cross vault without and with the textile-reinforced mortar used as a strengthening solution. The specimen was tested in the scope of the European project SERA.ta 07 “Seismic Response of Masonry Cross Vaults: Shaking table tests and numerical validations”. T...
An Integrated Data Acquisition Approach for the Structural Health Monitoring an...
Karanikoloudis, Georgios; Barontini, Alberto; Mendes, N.; Lourenço, Paulo B.The structural health monitoring (SHM) of buildings provides relevant data for the evaluation of the structural behavior over time, the efficiency of maintenance, strengthening, and post-earthquake conditions. This paper presents the design and implementation of a continuous SHM system based on dynamic properties, base accelerations, crack widths, out-of-plane rotations, and environmental data for the retrofitt...
Seismic behaviour and strengthening of rammed earth constructions
Oliveira, Daniel V.; Romanazzi, Antonio; Silva, Rui André Martins; Barontini, Alberto; Mendes, N.The widespread use of earthen buildings can be accredited to the local availability of the raw material, sustainability of the building process, and low cost. Earthen structures suffer from high seismic vulnerability, resulting from the low strength of the material, high mass, and lack of engineering approaches in design and building. Despite the extensive use of rammed earth structures, the structural behaviou...