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A close relationship between civil protection organizations and scientific community is widely recognized today at international and European level as being of paramount importance for the effectiveness of research products in their application for disaster risk management. In this perspective, European research projects on risks are more and more focused on application oriented outcomes, requiring the involvement of civil protection organizations, and creating a well-structured knowledge network within a European civil protection framework. For about forty years, the Italian civil protection has been relying upon the contribution of the scientific community to find the best solutions based on the most advanced and consolidated knowledge, for activities that concern the management of the entire disaster risk cycle. The interactions between civil protection and scientific community in Italy are mainly based on the so-called Competence Centers, i.e. the scientific operational partners of the Civil Protection Department (DPC), and on the Major Risks Commission, i.e. the technical-scientific advisory body of DPC. They both work with an interdisciplinary, multisectoral and, when necessary, multi-hazard risk approach. This paper aims to describe how Competence Centers presently operate, in a way that has evolved over the years. The focus will be on scientific activities and products related to the earthquake and structural engineering science, emphasizing the way of operating and collaborating of Competence Centers, consistently with the principles of the Italian Civil Protection Code. [ABSTRACT FROM AUTHOR]

This paper investigates the creation and use of integrated IFC models to modernise traditional processes for applications to building authorities for structural engineering approvals and permits. First, we provide a brief overview of e-permit systems in the AEC sector, with the focus on solutions that implement openBIM standards like IFC, MVD, and IDM. Second, we conduct a study on the information requirements of Italy's seismic-authorisation processes relating specifically to the field of structural engineering. Third, we describe preliminary research on defining the structural engineering information that needs to be incorporated in the IFC format for e-permitting scopes. Fourth, we present our early work on the development of an MVD that would enable the automatic extraction of integrated IFC models. Fifth, we illustrate the reference workflow of the Str.E.Pe. project and propose a preliminary proof-of-concept that makes use of an IFC model, which has been integrated with structural information to support the activities of the building authority in Avellino. The of- ficers there have developed a SWOT analysis using IFC models to assist them in assessing the compliance of structural projects with seismic requirements. Finally, the paper sets out additional research we intend to undertake and our conclusions. [ABSTRACT FROM AUTHOR]

The diffusion of seismic structural health monitoring systems, evaluating the dynamic response of engineering structures to earthquakes, is growing significantly among strategic buildings. The increasing availability of valuable vibration data is being backed by continuously evolving techniques for analysing and assessing structural health and damage. Within this framework, the paper proposes a novel model-driven vibration-based methodology to support the assessment of the damage level in masonry buildings hit by earthquakes. The leading idea is to exploit, in the pre-event phase, synthetic equivalent-frame modelling and nonlinear dynamic analyses to systematically relate the gradual reduction of natural frequencies to increasing levels of structural damage. The resulting behavioural chart (seismic chart) of the building, constructed by employing computational tools and robustly defined on a statistical base, may provide the theoretical expectation to ascertain a certain level of seismic damage, based on the decrease in vibration frequency experimentally identified in the post-event phase. The methodology is firstly formalized, integrating common identification techniques with a novel damage grade estimation procedure, and finally exemplified for a monitored strategic masonry building damaged by the 2016–2017 Central Italy earthquake sequence. The outcomes of this application confirm the operational validity of the methodology, which can be intended as effective support for the decision-making process regarding structural usability and safety in the post-earthquake scenario. [ABSTRACT FROM AUTHOR]

The Seismic Microzonation of level 3 (SM3) is nowadays a world-wide accepted tool for the mitigation of seismic risk. The SM3 is a complex process involving different disciplines ranging from Geology and Applied Seismology to Structural and Geotechnical Engineering. The outcome of a SM3 is presented on a zoning map in terms of a selected ground shaking intensity parameter and susceptibility to main ground instability (soil liquefaction, settlements, landslides, fault ruptures). In an advanced SM3 study for a given area, four main interdisciplinary steps can be recognized: (1) definition of the reference input motions, (2) construction of the subsoil model, (3) performing of numerical analyses and computing of amplification factors, (4) identification of zones with different geotechnical hazard potential and drawing up of the SM3 map. After the 2016–2017 Central Italy seismic sequence, intensive studies have been performed to obtain SM3 maps in 137 municipalities most damaged by the earthquakes. The aim of these studies has been to obtain a clear background on site effects to perform a correct reconstruction of the municipalities. In the paper, main results and critical issues of the above-mentioned steps of SM3 procedure are discussed together with some remarks on the use of SM3 output in supporting seismic design for reconstruction. [ABSTRACT FROM AUTHOR]

The unreinforced masonry (URM) buildings designed to be conforming with the Italian building code, as illustrated in the companion paper, were analyzed by performing time-history analyses on models realized using an equivalent frame approach and by adopting two different constitutive laws. Both the effect of record-to-record variability and of epistemic and aleatory uncertainties in modelling were explored. The achieved results constitute the basis for the evaluation of the risk level implicit in Italian code-conforming buildings. Two main performance conditions are considered, namely usability-preventing damage and global collapse limit states. [ABSTRACT FROM AUTHOR]

Two 5.9 M w and 5.8 M w earthquakes hit Emilia-Romagna region on May 2012. Most of the precast RC one-story structures exhibited significant damage, causing huge economic losses as well as deaths. These events produced in-situ observations and data to develop a deeper knowledge on the seismic behavior and collapse of this structural typology. This paper deals with the seismic assessment of a real precast RC industrial building with friction connections. The structure is located in Emilia-Romagna region and it was severely damaged during the second seismic event on May 29th. Structural columns exhibited cracking and yielding at the base as well as significant rotations along one direction. Moreover, relative displacements were recorded in both beam-to-column connections and roof-to-beam connections and several loss of support phenomena occurred for the roof elements. A detailed nonlinear structural model is defined in OpenSees code and nonlinear dynamic analyses are performed with the recorded accelerations time-histories of the two seismic events. By comparing the numerical results with the actual response of the structure, the adopted model is validated and the main damage typologies are also justified. [ABSTRACT FROM AUTHOR]

Soon after the earthquake that damaged L'Aquila municipality and its Province in the Abruzzi Region, Italy, on the 6th of April 2009, a widespread damage and usability assessment of buildings was launched. In 3 months, about 70,000 buildings were inspected, with the AeDES form, by public servants and professionals coordinated by the Italian Civil Protection Department. The paper, after describing the procedures and the form that were used for the assessment, discusses the time evolution of the inspections and analyses the data on building type and seismic damage. The empirical damage distribution conditional upon seismic intensity and building type is provided and the role of several vulnerability factors, such as the quality of masonry, the construction year, the number of stories, and the pre-existing damage, is highlighted. Lastly the damage consequences, such as the immediate occupancy conditional upon building damage and building type, are reported. [ABSTRACT FROM AUTHOR]

This paper examines how surveying and monitoring improve our knowledge about ancient buildings, allow the interpretation of their structural response and help in the search for the best solutions for their conservation. The case study of Palazzo del Capitano in Mantua (Italy) is analyzed. In particular, the attention is focused on the use of a Terrestrial Laser Scanner (TLS) for surveying and monitoring too, considering that the building structural control has been performed in combination with other traditional topographic techniques such as geometric leveling and topographic networks for 3D control based on measurements through total stations. The study of TLS monitoring has been tested only in the last decade and it is an innovative method for the detection of displacements of particular surfaces. Till now the research has focused only on the use of TLS monitoring to control large structures and in particular landscape situations; thus its use for a civil construction and historical buildings is a new field of investigation. Despite the fact technological development and new methodologies seem offer new future potential for the analysis of ancient buildings, currently there are still important limits for the application of the investigated surveying and monitoring techniques. [ABSTRACT FROM AUTHOR]

Abstract: In this paper the reliability in the load predicting ability of a design approach currently used in Italy for the repair of decayed end-beams of old elements was experimentally evaluated. The evaluation was carried out by using two different epoxy resins and two different materials for the connecting rods (namely steel and CFRP), used both on new graded beams and on 70years old elements. Results evidenced that specimens failed invariably at the prosthesis side (and not at the solid wood side), and that for larger sections load values were higher than those obtained on the basis of calculations. However, the expected mechanism of collapse (i.e., pull-out of glued-in rods) was never observed in tests, except as a consequence of other failure mechanisms. In contrast, specimens evidenced the splitting of wood close to rods, which was unexpected according to the considered design approach. Several criteria were compared in order to take account of the experimental evidences, and among them, one was the best performing. Although this work evaluated an approach also based on a national document, the results achieved and the fact that similar procedures are also considered in other national codes give to the outcomes a general validity, which can be effectively applied in similar cases. [Copyright &y& Elsevier]

The 2009 L'Aquila, Italy earthquake highlighted the seismic vulnerability of historic masonry building structures due to improper 'strengthening' retrofit work that has been done in the last 50 years. Italian seismic standards recommend the use of traditional reinforcement techniques such as replacing the original wooden roof structure with new reinforced concrete (RC) or steel elements, inserting RC tie-beams in the masonry and new RC floors, and using RC jacketing on the shear walls. The L'Aquila earthquake revealed the numerous limitations of these interventions, because they led to increased seismic forces (due to greater additional weight) and to deformation incompatibilities of the incorporated elements with the existing masonry walls. This paper provides a discussion of technical issues pertaining to the seismic retrofit of the Santa Maria di Collemaggio Basilica and in particular, the limitations of the last (2000) retrofit intervention. Considerable damage was caused to the church because of questionable actions and incorrect and improper technical choices. [ABSTRACT FROM AUTHOR]

An earthquake sequence struck the province of L'Aquila (central Italy) leaving 305 dead, about 1,500 injured, and 29,000 homeless. Hundreds of low-intensity events occurred between January and March, 2009. The mainshock took place on April 6, 2009, and its epicenter was located at about 6 km southwest of L'Aquila town; three stronger aftershocks happened on April 7 and 9, 2009. This paper focuses on actual performance of older and more recently constructed building structures during the earthquake sequence. After the main seismological characteristics of the sequence are described, the most significant observed damages are analyzed and associated with theoretical failure modes for both reinforced concrete and unreinforced masonry buildings. Since older masonry structures were more seriously damaged, the effects of the earthquake are described with more emphasis to ordinary masonry and cultural heritage buildings (churches, palaces, and castles). In conclusion, a number of lessons may be learned from the L'Aquila earthquake sequence. Several features are highlighted and some proposals are given to upgrade the current methods of structural analysis, as well as the existing codes. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the time evolution of the uncertainty effects associated with the different parameters defining the probabilistic structural performance of two existing cable-stayed bridges in Italy. The study is developed by using a general methodology for time-variant reliability analysis of concrete structures subjected to diffusive attacks from external aggressive agents. The time evolution of the probabilistic structural performance is analyzed with reference to proper indicators of the nonlinear behavior. The beneficial effects of prescribed rehabilitation interventions are also taken into account. The effects of each random variable on such indicators for both damaged and rehabilitated structures are quantified and compared by means of suitable time-dependent sensitivity factors. The obtained results show that the relative importance of the uncertainty effects associated with each random variable may vary significantly over time, and that this variation is considerably reduced by the adopted rehabilitation interventions. [Copyright &y& Elsevier]

The work described herein was conducted within the framework of an ongoing research program on the dynamic behavior of the Tower of Matilde, the bell tower of the Cathedral of San Miniato, Pisa, Italy, an interesting case study for its current structural arrangement and the modifications it has undergone over the centuries. This paper (Part I) details the experimental analyses performed in order to obtain an accurate measure of both the motion of the tower’s bells and, consequently, the time function of the dynamic actions transmitted to the tower during their motion. We then demonstrate how it is possible to arrive at an accurate, even though approximate, analytical description of both the bells’ motion and their actions by means of only a few experimental measurements and a simple mechanical model (also called in the following additional mass model). [ABSTRACT FROM AUTHOR]