Recent major earthquakes in the Italian territory have reaffirmed the seismic vulnerability of precast industrial buildings typical of the past Italian building practice, highlighting structural deficiencies observed during previous events and mostly related to the transfer of the horizontal forces between structural and non-structural elements. Intrinsic lack of shear and ductility capacity has been observed in simply supported beam-to-joist and beam-to-column connections, mainly constituted by vertical steel dowels or solely relying on shear friction, with or without neoprene pads. These connections were designed neglecting seismic loads and their premature failure was observed during the recent seismic events causing the loss of support of beam elements, due to elements relative movements, and the collapse of part of the buildings, mainly the roof. The seismic displacement demand of the considered industrial buildings is larger compared to traditional reinforced concrete frame structures due to their higher flexibility, according both to higher inter-storey height and a cantilevered static scheme. Furthermore, this high flexibility could also result into displacement incompatibility between structural and non-structural elements, such as precast cladding panels, causing their connection failure. On the basis of detailed field observations on a relevant number of buildings, collected just after the earthquakes, seven representative industrial facilities are examined to outline the main vulnerabilities of one-storey precast concrete structures not designed and detailed for seismic loads.

All rights reserved. No part of this publication may be reproduced in any form or by any means, without the prior written permission of the Prestressed Concrete Institute. N ineteen seventy-nine was the 25-year Silver Jubilee of the founding of the Prestressed Concrete Institute. CONTENTS Part 6-Early History of Prestressed 163 Concrete in Colorado 'Ed Thwaits is now 85 years old and fives quietly in Denver, Colorado.

In this paper, an integrated approach targeting sustainability, safety, and resilience is envisioned for the renovation of the post-World War II RC buildings clustered in urban outskirts. The solution stems as an enhancement of the widespread camouflage practice, which targets energy efficiency and architectural restyling by complementing the building with a technological double skin, self-supported on an independent exoskeleton. Based on this integrated approach, the exoskeleton can be further engineered to also enable structural safety and resilience. Life cycle thinking is addressed to re-conceive traditional structural design approaches, guaranteeing safety, while minimizing costs and environmental impacts over the building life cycle. Accurate selection of materials and dry technologies enables adaptability, reparability and maintenance, and total recyclability/reuse at end-of-life. The intervention is carried out from outside, avoiding relocation of the inhabitants and possible building downtime. The paper introduces a possible framework for engineers, technologists, and architects to design new holistic renovation interventions, for which innovative solution sets are required. Possible structural techniques to be coupled with energy refurbishment are proposed. As a proof of concept, the envisaged holistic renovation strategy is applied to a reference building, and benefits entailed in combining structural safety measures within an integrated intervention are commented.

His research activities include the seismic design and retrofit of precast and reinforced concrete bridges and buildings.

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The paper investigates the in-plane performance of horizontal precast reinforced concrete (RC) cladding panels, typically adopted in one-storey precast industrial and commercial buildings.Starting from in-field observations of cladding panels failures in recent earthquakes, the seismic performance of typical connections is evaluated by means of experimental tests on full-scale panels under quasi-static cyclic loading. The failure mechanisms highlight the vulnerability of such connections to relative displacements and, therefore, the need to accurately evaluate the connections displacement demand and capacity.An analytical model is developed to describe the force-displacement relationship of the considered connections and compared to the experimental results. In order to determine the seismic vulnerability of such connections and provide design recommendations, linear and nonlinear analyses are conducted taking as reference a precast concrete structure resembling an industrial precast building. The results of the analyses show the importance of a correct estimation of the column's lateral stiffness in the design process and how an improper erection procedure leads to a premature failure of such connections.

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