Nonlinear Dynamic Response of a Precast Concrete Building to Sudden Column Removal

: Robustness of reinforced concrete (RC) structures is an ongoing challenging research topic in the engineering community. During an extreme event, the loss of vertical load-bearing elements can activate large-deformation resisting mechanisms such as membrane and catenary actions in beams and floor slabs of cast-in-situ RC buildings to resist gravity loads. However, few studies have been conducted for precast concrete (PC) buildings, especially focused on the capacity of such structures to withstand column loss scenarios, which mainly relies on connection strength. Additional resistance resource and alternate load paths could be reached via tying systems. In this paper, the progressive collapse resistance of a PC frame building is analyzed by means of nonlinear dynamic finite element analyses focusing on the fundamental roles played by beam-to-column connection strength and tying reinforcement. A simplified modelling approach is illustrated in order to investigate the response of such a structural typology to a number of sudden column-removal scenarios. The relative simplicity of the modelling technique is considered useful for engineering practice, providing new input for further research in this field

Robustness-oriented conceptual design of precast concrete frame structures

Ongoing research on structural robustness of precast concrete (PC) structures is a source of debate in the structural engineering community because few studies are currently available in the literature exploring it thoroughly. The importance of preventing progressive collapse of such structures relies upon redistribution capacity of structural members through connections and tying systems. A recent study has demonstrated that continuous ties along members can substantially improve the progressive collapse performance of PC buildings. In this paper, quantitative data from nonlinear dynamic analyses of a frame structure under peripheral column removal at different floors is processed to identify the most demanding scenarios. Furthermore, the dependency of the robustness assessment on the ties’ mechanical properties has been investigated both in terms of resistance and ductility. Finally, some remarks concerning the design of key elements, such as columns placed at the corner of the building, are given. The study is aimed at driving the conceptual design of PC frame structures towards robust solutions able to mitigate the risk of progressive collapse under extreme events

Bari-Santiago-Bari. Il viaggio, il pellegrinaggio, le relazioni

La giornata di studio e gli Atti hanno registrato il contributo di storici, antropologi, studiosi di letteratura e di teatro, storici dell’arte: infatti, un tema complesso come il pellegrinaggio, come scrive Paolo Caucci von Saucken nel suo saggio, «non può essere che studiato in una prospettiva interdisciplinare e in relazione all’intera civiltà che lo ha generato» e il pellegrinaggio compostellano deve essere visto in connessione con quello diretto a Roma, a Gerusalemme, a Monte Sant’Angelo. Al centro della riflessione sono il cammino e il viaggio di persone, di modelli, di artisti e di opere tra territori lontani uniti da una rete di percorsi, di strade, di relazioni. L’attenzione è stata rivolta alla ricostruzione della ricerca scientifica compostellana, ai pericoli del viaggio, alla figura di San Giacomo e al suo culto, alla tradizione letteraria e teatrale, ai Cammini europei verso Compostella, ai riconoscimenti del Cammino di Santiago da parte del Consiglio d’Europa e dell’Unesco, all’immagine del pellegrino, alle relazioni artistiche tra la Puglia e la Galizia in particolare nel Medioevo e in Età moderna