Design Guidelines for Connections of Precast Structures under Seismic Actions

This document has been drafted within Work-Package WP6, “Derivation of design rules” of the project SAFECAST (Performance of Innovative Mechanical Connections in Precast Building Structures under Seismic Conditions), Project FP7-SME-2007-2 Programme – Grant Agreement n. 218417, 2009). The provided guidelines have a theoretical derivation supported by the experimental results of the testing activities and the numerical simulations performed as a part of the project as well as by the general know-how on production practice and international literature on the subject.JRC.G.5-European laboratory for structural assessmen

Reinforced concrete design to Eurocode 2

This textbook describes the basic mechanical features of concrete and explains the main resistant mechanisms activated in the reinforced concrete structures and foundations when subjected to centred and eccentric axial force, bending moment, shear, torsion and prestressing,. It presents a complete set of limit-state design criteria of the modern theory of RC incorporating principles and rules of the final version of the official Eurocode 2. This textbook examines methodological more than notional aspects of the presented topics, focusing on the verifications of assumptions, the rigorousness of the analysis and the consequent degree of reliability of results. Each chapter develops an organic topic, which is eventually illustrated by examples in each final paragraph containing the relative numerical applications. These practical end-of-chapter appendices and intuitive flow-charts ensure a smooth learning experience. The book stands as an ideal learning resource for students of structural design and analysis courses in civil engineering, building construction and architecture, as well as a valuable reference for concrete structural design professionals in practice

Vulnerabilità Sismica degli Edifici Prefabbricati Esistenti: Analisi di un Edificio Critico Senza Diaframma di Copertura

The present work reports the analyses made on one of the critical buildings which had a relevant diffusion over the Italian territory, from the 60s up to the 90s of last century, for storehauses and agricultural destinations. It is characterised by shed beams and interposed rafters forming roofs without any diafragmatic stiffness. The seismic behaviour of this type of building has been investigated by means of modal dynamic analyses with standard response spectra. The results of the assessments indicate the levels of seismic capacities that can be expected and the effectiveness of possible simple retrofitting intervenctions.JRC.G.5-European laboratory for structural assessmen

Prove pseudodinamiche su prototipi di strutture prefabbricate

The paper presents the results of pseudodynamic and cyclic tests performed at ELSA Laboratory in Ispra on full scale prototypes of precast structures for one-storey industrial buildings. The typical frame system, with hinged beam-to-column connections, largely used for this type of buildings in Italy and in many other European countries is investigated. The results give clear indications on the seismic behaviour of such structures in terms of strength capacity, ductility resources, reinforcement details and role of the different construction elements (connections, roof diaphragm, cladding panels). The large ductility resources with large plastic deformations, joined to a strong attenuation of the response due to long natural vibration periods, leads to high strength capacity evaluated around 1 g of peak ground acceleration. For design purposes the due limitation of storey drift may become the limiting requirement.JRC.DG.G.5-European laboratory for structural assessmen

Capacity design and seismic performance of multi-storey precast structures

The seismic design of multi-storey precast structures is at present not covered by specific provisions of the European seismic codes. To fill such gap, capacity design criteria for multi-storey precast concrete frames with hinged beams are presented. Based on the same approach prescribed by the codes for monolithic cast-in-situ frames, a distribution of floor forces and a value of behaviour factor are assumed to perform a static linear analysis of the structure. A parametric study aimed to validate the design method is carried out by varying, within the range of practical interest, the main design parameters such as the number of storeys, the mass-over-stiffness ratios and the stiffness characteristics of the columns. The results of dynamic modal analyses and non linear static analyses show that the proposed method can safely be applied to ordinary multi-storey concrete precast frames characterized by structural regularity and limited flexibility.JRC.DG.G.5-European laboratory for structural assessmen