Publications

In order to promote an effective approach to the prevention of and preparedness for disasters, the countries participating in the Union Civil Protection Mechanism (UCPM) shall develop risk assessments, risk management capability assessments and disaster risk management planning at national or appropriate sub-national level. The European Commission is providing scientific support to the countries participating in the UCPM, publishing updated guidelines to facilitate the development of their National Risk Assessments (NRAs). Earthquake is among the most common hazards considered in NRAs prepared by the countries participating in the UCPM. Indeed, in 2018 NRAs, more than 20 countries performed risk assessment for earthquakes, and some considered cross-border and cascading effects, such as tsunami, landslides, disruption of infrastructure and industrial accidents. This paper surveys and summarises the current state of research that can be utilized for national seismic risk assessment. It aims to facilitate the development of consistentNRAs with respect to earthquakes and ensure their utility in seismic risk management planning. It also aims to support the use of the new reporting guidelines on disaster risk management among countries participating in the UCPM. The seismic risk assessment process is described as outlined in ISO 31000: 2018. A wealth of hazard, exposure, vulnerability and damage-to-loss models, methodologies and tools are presented to serve the purpose of conducting national seismic risk assessment. References to relevant European research projects, good practices, and software to support the assessment are also provided.

The metropolitan area of Lisbon is the region of Portugal with the highest seismic risk, given the coexistence of moderate-to-high hazard with highpopulation density and building stock exposure. The present work addresses the seismic risk assessment of pre-code masonry buildings in this region, accounting various typological classes and conservation states in order to evaluate the consequences in terms of economic losses. The analyses are conducted through a seismic probabilistic approach, considering the sitespecific ground motion through a non-stationary stochastic method. The results can serve as a useful guide for decision-making in developing regional seismic risk mitigation strategies.

Given the 516 Arouca pedestrian suspension bridge

Azores Islands are seismically active due to the tectonic structure of the region. Since the 15th century, they have been periodically shaken by approximately 33 moderate to strong earthquakes, with the most recent one in 1998 (Mw = 6.2). Nonetheless, due to insufficient instrumental seismic data, the region lacks a uniform database of past real records. Ground motion simulation techniques provide alternative region-specific time series of prospective events for locations with limited seismic networks or regions with a seismic gap of catastrophic earthquake events. This research establishes a local ground motion model (GMM) for the Azores plateau (Portugal) by simulating region-specific records for constructing a homogeneous dataset. Simulations are accomplished in bedrock using the stochastic finite-fault approach by employing validated input-model parameters. The simulation results undergo validation against the 1998 Faial event and comparison with empirical models for volcanic and Pan-European datasets. A probabilistic numerical technique, namely the Monte-Carlo simulation, is employed to estimate the outcome of uncertainty associated with these parameters. The results of the simulations are post-processed to predict the peak ground motion parameters in addition to spectral ordinates. This study uses XGBoost to circumvent the difficulties inherent to linear regression-based models in establishing the form of equations and coefficients. The input parameters for prediction are moment magnitude (Mw), Joyner and Boore distance (RJB), and focal depth (FD). The quantification of GMM uncertainty is accomplished by analyzing the residuals, providing insight into inter- and intra-event uncertainties. The outcomes demonstrate the effectiveness of the suggested model in simulating physical phenomena.

The characteristic values of temperature corresponding to the maximum and minimum shade air temperature with an annual probability of being exceeded 0.02, used in the European construction standard for thermal actions (EN 1991-1-5:2003), are usually assessed at a country level and included in the National Annexes to that Eurocode part.The paper aims to support national authorities on elaborating maps for thermal actions using publicly available datasets, consistent at a European level, and harmonised modelling approaches. In addition, these datasets are continuously updated, reflecting the current climate and capturing potential global warming variations.The work investigates how updates in data and modelling could affect the characteristic values currentlyadopted in the Italian National Annexes to the Eurocodes. The main results show that: (i) the currently adoptednumber and locations of the weather stations result fairly representative of the patterns detected by exploitingadditional datasets; ii) the statistical method plays an essential role in the assessment of characteristic values, i.e., the method adopted in the current Italian standard evaluates more conservative characteristic values of maximum temperature than Gumbel or Generalized Extreme Value distributions, but could err on the unsafe side for minimum ones; (iii) both E-OBS and ERA5-Land datasets represent two optimal products to be used as a common source of temperature values at European scale; (iv) moving towards an updated period for temperature data results on an increase of characteristic values of maximum temperature and limited variations in spatial extent and magnitude of characteristic values of minimum ones.

The present work analyses the wind load effects on the 516 Arouca bridge, the world's longest pedestrian suspension bridge in 2020. Computational fluid dynamics (CFD) was used to model a range of wind incidence angles between -8

The safety and resilience of school buildings against natural disasters is of paramount importance since schools represent a reference point for communities. Such significance is not only related to the direct consequences of collapse on a vulnerable part of the population, but also due to the importance of schools in the post-disaster recovery. This work is focused on the risk and resilience assessment of school buildings in Lisbon (Portugal) under seismic events. The results of this study, in which a subset of 32 schools are analyzed, are used to define a prioritization strategy to mitigate the seismic risk of the Lisbon City Council school building portfolio and to assess the overall resilience of the school network. Numerical modeling of the school buildings is performed in order to estimate losses in terms of the built-up area of the schools and recovery times associated with different seismic scenarios, which are probabilistically defined specifically for the sites of the buildings, accounting for the local soil conditions and associated amplification effects. Based on the obtained risk estimates, which are compared to reference values established on international guidelines and specialized literature, the Lisbon City Council and LNEC jointly defined a short- and medium-term risk mitigation plan, starting with a detailed inspection and assessment of the most vulnerable school buildings and continuing to the implementation of retrofitting measures.

Probabilistic seismic hazard assessment (PSHA), despite its deep criticism, is still the most common tool used to decide on the acceptable seismic risk and corresponding mitigation measures. We propose two consistency tests to address the variability of earthquake generation models found in PSHA studies: (i) one rule-of-thumb test where the seismic moment release from the model is converted to an average slip on a typical fault and compared with known plate kinematics or GNSS deformation field and (ii) a test where using a neotectonic model the computed deformation is converted into seismic moment release and to a synthetic earthquake catalogue. We apply these tests to W and SW Iberia slowly deforming region, where two earthquake source areas are investigated: (1) the Lower Tagus Valley, one of the largest seismic risk zones of Portugal; and (2) the offshore SW Iberia area, considered to be the source for the 1 November 1755 event (M

Procuram-se sintetizar neste artigo os principais aspetos relacionados com a avaliação e a reabilitação sísmica de edifícios existentes de alvenaria, compatibilizando a NP EN 1998-3:2017 com os respetivosAnexo C, específico para edifícios de alvenaria, e Anexo Nacional, específico para Portugal.A avaliação sísmica é um procedimento quantitativo através do qual se verifica se um edifício existente, danificado ou não, satisfaz os requisitos de desempenho, definidos por uma combinação de um estado limite com um nível de ação sísmica, através de critérios de conformidade. Neste procedimento estão envolvidos a definição da ação sísmica, a modelação da estrutura, os métodos de análise para determinação dos efeitos das ações e as verificações de segurança. São abordados os métodos de análise, dois lineares e dois nãolineares, aplicáveis a edifícios existentes de alvenaria, bem como as recomendações específicas do Anexo C e as informações complementares do Anexo Nacional.

The response of three full-scale unreinforced masonry buildings, without specific seismic detailing, as observed in shake table testing at LNEC for a seismic action representative of induced seismicity, is presented. The first building specimen simulated the upper floor and roof of the end-unit of a two-storey terraced house, built with unreinforced cavity walls, a reinforced concrete slab and a pitched timber roof. The second specimen was a replica of the roof of the first building. The third specimen represented instead a one-story detached pre-1940

Typical low-rise masonry construction in regions such as Europe, Australia and New Zealand consists of cavity or solid URM walls covered with various timber roof configurations generally supported by masonry gables. The flexibility of these light timber roof systems has been reported to have significant effect on the seismic performance of the structure as a whole. Post-earthquake observations and experimental outcomes highlighted the large vulnerability of the URM gable walls to the development of overturning mechanisms, both due to the out-of-plane excitations and the in-plane timber diaphragm deformability. This paper presents a full-scale collapse shake-table test on a Dutch roof substructure composed by wooden planks supported by timber beams lying on masonry gable walls. After attaining the collapse of the gable walls, the timber roof diaphragm was subjected to a supplementary quasi-static cyclic pushover test for a complete characterization of the system response. The test is a part of a wider research project aimed at assessing the vulnerability of URM buildings in Groningen, a region of the Netherlands not naturally prone to seismic events, but which has recently been exposed to induced seismicity. The presented results include the damage evolution, the collapse mechanism and the hysteretic response of the specimen.

This paper discusses the results of three dynamic shake-table tests, performed on full-scale unreinforced masonry buildings without specific seismic detailing. The testing program is part of a wider research project aimed at assessing the seismic vulnerability of buildings typical of the Groningen region, located in Northeast of the Netherlands. This area, historically not prone to tectonic ground motions, in the recent years has been subjected to earthquakes induced by reservoir depletion due to gas extraction. The first building specimen simulated the end-unit of a two-story terraced house, built with unreinforced cavity walls. These walls were composed of an inner load-bearing leaf, made of calcium silicate bricks supporting the floors, and an outer veneer, made of clay bricks with aesthetic and weather-protection function. The two leafs were interconnected by distributed metal ties. The floors consisted of reinforced concrete slabs, providing rigid diaphragms in their plane. The pitched roof was made of longitudinal timber purlins, supported by end gables perpendicular to the shaking direction, and wood boards. The second specimen was a replica of the second story and the attic of the first building, with identical details for walls, slab, and roof framing tested to study the collapse mechanism. The third specimen represented instead a one-story detached pre-1940s house, built with double-wythe unreinforced clay masonry walls. The prototype structure was designed to include large openings and a re-entrant corner, causing significant horizontal irregularities. The first floor was made of timber beams and planks, resulting in a flexible diaphragm. The steep-pitch roof consisted of a series of timber trusses connected by wood purlins and boards. The two façades perpendicular to the shaking direction were designed in order to represent two common gable geometries.

Seismic risk has been the focus of a number of European projects in recent years, but there has never been a concerted effort amongst the research community to produce a uniform European risk model. The H2020 SERA project has a work package that is dedicated to that objective, with the aim being to produce an exposure model, a set of fragility/vulnerability functions, and socio-economic indicators in order to assess probabilistic seismic risk at a European scale. The partners of the project are working together with the wider seismic risk community through web tools, questionnaires, workshops, and meetings. All of the products of the project will be openly shared with the community on both the OpenQuake platform of the Global Earthquake Model (GEM) and the web platform of the European Facilities for Earthquake Hazard and Risk (EFEHR).

Reinforced concrete (RC) frames subjected to seismic loading often depict localized member-end deformations due to strain penetration effects between adjacent members, such as beam-column and column-footing joints. Past experimental programs indicate that the bond-slip deformations occurring at the interface between the reinforcement and the surrounding concrete can contribute up to 40% of the lateral deformation of the RC members.Despite the recognized importance of strain penetration effects on the response of RC structures, the consideration of such effects in numerical models is still limited. The employment of advanced bond-slip models within detailed finite element formulations, capable of simulating continuous domains with highly discretized meshes, has witnessed great advances over the recent years with encouraging results. Nonetheless, this modelling approach is computationally heavy and hence inapplicable for practical seismic (nonlinear) analysis of structures.Alternatively, the use of beam-column elements with lumped or distributed plasticity is a more computationally efficient and engineering-friendly modelling approach. Unfortunately, the elements of this type available in conventional numerical packages did not yet consider an explicit simulation of the interface between the reinforcing bars and the surrounding concrete along their embedment length. In other words, the inclusion of bond-slip effects in beam element models has been essentially achieved through simplified formulations based on empirical relationships.The present study aimed at overcoming the foregoing limitation by developing an explicit bond-slip model applicable to general fibre-based beam-column elements. Using a state-of-the-art bond-slip constitutive model, the current paper introduces a zero-length element that computes the localized member-end deformations accounting for the bond-slip response at each reinforcing bar of a given RC section. Along with the material properties and anchorage conditions, the proposed nonlinear model also accounts for cyclic degradation and rebar yielding effects. Validation studies conducted with the proposed numerical formulation reveal a good agreement with past experimental tests, evidencing an important stability and accuracy at the expense of an acceptable additional computational effort.

The research findings made in recent years now mean that the prospect of accounting for soil-foundation-structure interaction within seismic design is becoming a viable reality. By examining the cyclic response of a parameterized set of shallow foundations, simulated using a recently developed macro-element model that accounts for rotational-vertical-horizontal motion interaction and which considers coherently possible uplift behaviour, new degradation curves for the stiffness and damping of shallow foundations are developed. The improvements included in these curves with respect to previous proposals are: i) the uplift mechanism, a non-dissipative nonlinear mechanism, is taken into account and ii) the overturning moment and the corresponding simultaneous horizontal load are applied on the footing so that the effect of shear force on the overall response is investigated.It is found that rotational stiffness degradation is more severe when shear demands are relatively large compared to flexural demands. Moreover, the stiffness degradation becomes more intense as the static factor of safety for centred vertical loads on the foundation reduces, since the response tends to be dominated by hysteretic behaviour in contrast to an increasingly rigid-body rocking response for larger factors of safety. Hysteretic energy dissipation evolution is represented via equivalent viscous damping curves, obtained from quasi-static cyclic analyses.Finally, the new set of stiffness and damping curves are included for use within the direct displacement-based design framework. By using the improved curves, the bearing capacity of the foundation will be automatically respected since each point of the developed curves will correspond to a solution lying inside or on the ultimate load surface of the foundation system. The benefit of this approach is illustrated through the design of 6-, 8- and 12-storey buildings with and without taking into consideration soil-foundation-structure interaction. Nonlinear dynamic analyses are used to gauge the performance of the design solutions, and it is found that, even though the prediction of foundation rotation demands can be further improved, the direct displacement-based design method provides good control of storey drifts and displacements, suggesting that it could be a valuable procedure for performance-based earthquake engineering in the future.

As estruturas em casca de formas livres ultrafinas são caracterizadas por terem capacidade portante decorrente da sua própria forma. Estas estruturas em casca, ao serem construídas em betão de ultra-elevado desempenho, podem ter espessuras extremamente finas que lhes confere uma imagem de esbelteza e beleza bastante apreciada. A complexidade das formas arquitetónicas destas estruturas em casca exige uma descrição mais exacta da ação do vento e da interação com estas estruturas. No presente trabalho analisa-se o comportamento aerodinâmico de cascas finas pré-fabricadas em betão de ultra-elevado desempenho, com forma triangular. O objetivo é avaliar a interação entre a casca e o vento para diferentes ângulos de incidência do vento bem como a influência de fachadas incorporadas no modelo. Para isso, foi realizada uma campanha de ensaios experimentais num túnel de vento do Laboratório Nacional de Engenharia Civil (LNEC), caracterizada por um perfil de velocidade do vento uniforme, a 20 m/s, em que se determinam os coeficientes de pressão internos e externos na superfície da casca. Foram ensaiadas três configurações distintas do modelo: i) sem fachadas, ii) com uma fachada e iii) com duas fachadas. Os resultados do ensaio são apresentados sob a forma de curvas isobáricas representativas de valores de coeficientes de pressão resultantes.

A arquitetura recorre, por vezes, a dispositivos de sombreamento de grandes dimensões, com formas e configurações de montagem cuja resposta à ação do vento carece de caracterização. Os sombreamentos em cascata, instalados no exterior de fachadas e constituídos por uma série de lamelas paralelas entre si, colocam desafios particulares do ponto de vista da avaliação aerodinâmica que condicionam a carga imposta pelo vento sobre as lamelas e, portanto, o correto dimensionamento dos apoios e da solução a adoptar. O presente trabalho pretende caracterizar experimentalmente o desempenho aerodinâmico das lamelas de um protótipo destes sombreamentos, através de ensaios em túnel de vento com um modelo

The aerodynamic design of a compact lightweight high-speed train is discussed. It is an isolated automotive vehicle with a capacity for forty passengers. The fore end geometry is very streamlined and the upper curvature radii are exceptionally large to delay flow separations. The particular duck-shape of the fore region of the nose is responsible for large transverse pressure gradients. The research, described in this paper, explores how the nose geometry and the yaw angle influence the pressure distribution and the three dimensional boundary layer on the nose of the train, causing limiting streamlines on the wall to converge along specific locations. A main goal is to understand if these patterns can be related with the onset of separations at yaw. A semi-analytic model for the skewed boundary layer was compared with RANS calculations. RANS simulations failed to reproduce the expected wall profile and seem to overestimate the diffusion in the boundary layer. On the other hand, the semi-analytic model seems to underestimate diffusion and should be refined with a better model for Reynolds stresses effects on the buffer layer.

Este trabalho tem como objetivos a caracterização e análise do comportamento dinâmico da plataforma sísmica triaxial do LNEC e da evolução das propriedades modais de um pórtico em betão armado com o dano acumulado em sucessivos ensaios sísmicos. Para esse fim foram analisadas as leituras da instrumentação utilizada em ensaios realizados na referida plataforma sísmica e foram desenvolvidos modelos numéricos de elementos finitos da mesa sísmica e do sistema completo mesa-pórtico. A plataforma sísmica foi caracterizada com base em ensaios de identificação dinâmica utilizando sinais de entrada constituídos por acelerações com conteúdo em frequência de banda larga, do tipo

O comportamento à compressão e à tração em paredes de alvenaria de fachada foi analisado através de uma campanha experimental. Foi desenvolvido um estudo localizado, precisamente na parte da ligação existente, através de conectores, entre uma parede de tijolo face à vista e uma parede de alvenaria de enchimento, que em situações reais se encontra inserida num pórtico de betão armado estrutural. Amostras de ligações quer da parede de tijolo face à vista, quer da parede de enchimento foram submetidos individualmente a carregamentos monotónicos de tração e cíclicos tração-compressão, simulando de alguma forma os carregamentos para fora do plano da parede de fachada. Este trabalho experimental teve como objetivos: (i) avaliar a influência de diferentes características dos ligadores, nomeadamente espessura, geometria e rigidez; (ii) avaliar um método de aplicação alternativo (ancoragem química) possível de adaptar a soluções de reabilitação e (iii) descrever e catalogar os tipos de rotura e comportamento de todas as soluções. Os resultados experimentais deste estudo demostraram que existem determinados parâmetros que têm mais importância no desempenho da ligação, contribuindo assim para uma melhor compreensão do comportamento das ligações submetidas a diferentes tipos de carga.

This book presents a selection of the best papers from the HEaRT 2015 conference, held in Lisbon, Portugal, which provided a valuable forum for engineers and architects, researchers and educators to exchange views and findings concerning the technological history, construction features and seismic behavior of historical timber-framed walls in the Mediterranean countries. The topics covered are wide ranging and include historical aspects and examples of the use of timber-framed construction systems in response to earthquakes, such as the gaiola system in Portugal and the Bourbon system in southern Italy; interpretation of the response of timber-framed walls to seismic actions based on calculations and experimental tests; assessment of the effectiveness of repair and strengthening techniques, e.g., using aramid fiber wires or sheets; and modelling analyses. In addition, on the basis of case studies, a methodology is presented that is applicable to diagnosis, strengthening and improvement of seismic performance and is compatible with modern theoretical principles and conservation criteria. It is hoped that, by contributing to the knowledge of this construction technique, the book will help to promote conservation of this important component of Europe

The applications of discrete elements models based on rigid block formulations to the analysis of masonry walls under horizontal out-of-plane loading is simplified block pattern are addressed. Two procedures for creating irregular block systems are presented, one using Voronoi polygons, the other based on a bed and cross joint structure with random deviations. A test problem provides a comparison of various regular and random block patterns, showing their influence on the failure loads. The estimation of manual frequencies of rigid block models, and its application to static pushover analyses, is addressed. An example of application of rigid block model to wall capacity problem is presented.

The overall aim of Sub-Project 10 (Earthquake disaster scenario predictions and loss modelling for urban areas) has been to create a tool, based on state-of-the-art loss modelling software, to provide strong, quantified statements about the benefits of a range of possible mitigation actions, in order to support decision-making by urban authorities for seismic risk mitigation strategies. A further larger aim has been to contribute to a seismic risk mitigation policy for future implementation at European level. Among the European cities for which loss estimation studies have been carried out are Istanbul, Lisbon and Thessaloniki, and tools, using GIS mapping, have been developed by research teams in each of these cities; these were made available for further development to examine mitigation strategies within SP10. Related research studies

Much work in Earthquake Engineering was devoted to the improvement of earthquake resistant design of new structures. One European result is EN 1998, which will be in several years the main seismic code for all European countries. But it is well known, that older existing structures cause in many large earthquakes much more casualties and damages than new structures. It is certainly not possible to retrofit all existing structures, but agreement exists, that assessment and retrofit of safety - critical - structures and lifeline structures must have priority. In September 2004 the European Integrated Research Project LESSLOSS on Risk Mitigation for Earthquakes and Landslides was started. The project will run for three years and comprises 13 Sub-Projects (SP´s). The consortium consists of 46 partners (see http:\\www.lessloss.org). LESSLOSS SP5 is on In-situ Assessment, Monitoring and Typification of buildings and Infrastructure. The project partners of SP5 are ARS, CESI, LNEC, RWTH and VCE. This Sub Project focuses mainly on the assessment of important existing structures and tries to integrate experimental methods into the assessment procedure. The progress of SP5 obtained in the first year is summarized in this paper. Highlights presented by all partners are mentioned and the assessment of Hospital Innsbruck is presented in more detail. The most innovative task of LESSLOSS/ SP5 is Update of vulnerability estimates via monitoring, which was also started in the first year.

In order to study the behavior of bridge structures in relation to traffic, wind and seismic loads, it is extremely important to know their actual dynamic properties (natural frequencies, vibration mode shapes and damping). The experimentally identified dynamic properties of bridge structures are also an effective way to characterize their actual global structural behavior. Whether included in the reception load tests of recently built bridges, before they are opened to the traffic, or as part of the inspection works of bridges already in service, LNEC has performed modal analysis studies based on the results of ambient vibration tests. Some of the studies carried out recently in important bridges are reported in this paper.

O sismo de Northridge ocorreu na parte norte da área metropolitana de Los Angeles, Califórnia, às 4:31 h do dia 17 de janeiro, uma segunda-feira coincidente com dia de feriado nacional, tendo atingindo uma magnitude de 6.6 na escala de Richter. O número total de vítimas mortais cifra-se em 57, havendo para cima de 8 000 feridos e 20 000 desalojados.As estimativas de perdas totais, feitas em meados de fevereiro de 1994, apontavam para valores de 15 biliões de US dólares, tendo o Estado da Califórnia apresentado um impacto económico total de ordem dos 30 biliões de dólares, perto do valor do Orçamento Geral do estado Português para 1994. Os prejuízos infligidos na indústria e no comércio são também surpreendentemente elevados, exigindo longos períodos de interrupção das atividades económicas.

Within the realm of natural hazards, geohazards are recognised as being particularly complex and often having the potential of triggering disasters. This complexity has led to increased political commitment and interest in engaging multi-stakeholder and citizens in disaster risk management. The AGEO project explored new forms to foster collaboration between civil society and authorities, using the rapidly developing field of citizen science and its innovative tool of citizens

Communicating science within disaster risk reduction using methods that encourage two-way dialogue between scientists and laypersons is a challenging task. This paper aims at presenting a methodological strategy of communicating risk and non-structural seismic protection measures through participatory approach. Such methodological strategy is part of a pilot experience of risk communication in two schools in Lisbon (Portugal) under the EU project KnowRISK (Know your city, Reduce seISmic risK through non-structural elements). The efficacy of education for seismic safety is often inhibited by an incomplete understanding of the process by which individuals decide to protect themselves from harm (Becker JS, Paton D,Johnston DM, Ronan KR. Nat Hazards 64(1):107

Most of the Lisbon 18th century timber-framed masonry

Good performance of non-structural elements can be decisive in saving lives and costs when an earthquake strikes. The European project KnowRISK aims to educate and encourage households to take the necessary precautionary measures to protect people, houses, and contents. Preparedness and prevention act on community resilience. Within the KnowRISK project, the idea of a Practical Guide has been conceived suggesting seismic mitigation solutions for non-structural components to non-experts stakeholders. It is intended to guide people into the first steps of prevention in a straightforward manner, minimizing or avoiding injuries, damage, and long-term financial consequences. The novelty of the Guide belongs to his philosophy: a path through increasing challenges corresponds to a growing level of safety. The idea is that anyone can mitigate seismic risk in its own environment by adopting simple and low cost measures. The Practical Guide may contribute to increase risk awareness. This kind of initiatives if undertaken at larger scales may also enhance social resilience.

When one of the dimensions of a structural member is not clearly larger than the two orthogonal ones, engineers are usually compelled to simulate it with refined meshes of shell or solid finite elements that typically impose a large computational burden. The alternative use of classical beam theories, either based on Euler-Bernoulli or Timoshenko

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This text reflects the first of the four lectures that the author has presented at Udine, Italy, at CISM

Um dos principais problemas e interesses da engenharia sísmica é a caracterizaçãoda acção sísmica, envolvendo a estimativa da intensidade, conteúdo em frequência,duração e variabilidade espacial dos movimentos intensos do solo mais gravosos, emtermos dos seus efeitos nas estruturas, que pode ocorrer num local.O presente trabalho de investigação desenvolve e aplica a metodologia estocástica etécnicas de modelação de fonte

Os sismos são encarados frequentemente como desastres naturais inevitáveis. Todavia,deveriam ser considerados fenómenos naturais, cujos efeitos adversos podem ser minimizadoscaso se proceda a uma gestão efectiva do risco sísmico.O objectivo principal do presente trabalho de investigação é o de avaliar o risco sísmicoem Portugal Continental.Sendo um tema de natureza multidisciplinar, apresentam-se e discutem-se modelos deavaliação probabilística da perigosidade sísmica e sua desagregação, de vulnerabilidade efragilidade sísmicas de tipologias construtivas, de danos e de perdas económicas e humanas.Aplica-se a análise probabilística da perigosidade sísmica, e sua desagregação, aPortugal Continental, obtendo-se cenários modais capazes de reproduzir os níveis deperigosidade que os condicionam. Apresenta-se o inventário do parque habitacional e seushabitantes, descriminado por factores de vulnerabilidade, e classifica-se a sua vulnerabilidadesegundo os modelos de dano. Procede-se à actualização e aferição de uma metodologia parasimulação de cenários sísmicos, integrada num Sistema de Informação Geográfico. Avalia-seo risco sísmico, seguindo diversas abordagens, comparando-se os resultados com o risco deoutros países.Construiu-se assim uma ferramenta de avaliação de perdas devidas a sismos, queconstitui uma primeira contribuição para o desenvolvimento de um processo de gestão dorisco sísmico aplicado ao Continente Português.

O parque habitacional de Portugal Continental contém algumas tipologias construtivas deelevada vulnerabilidade sísmica em relação às quais urge actuar no sentido de reduzir o riscosísmico a elas associado. No projecto de investigação

O Laboratório Nacional de Engenharia Civil (LNEC) participa atualmente numa das sete Tarefas, doprojeto Europeu SHARE- Seismic Hazard Harmonization in Europe, mais precisamente na tarefa nº 2,intitulada Requisitos de engenharia e aplicações.O presente relatório de progresso descreve a participação do LNEC na sub-tarefa 2.5 - Cenários derisco sísmico para cidades Europeias selecionadas

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No presente relatório pretendem-se apresentar e definir alguns das linhasorientadoras para a simulação do comportamento dinâmico de fluidos no interior deAmortecedores de Líquido Sintonizado (TLDs), de acordo com o proposto na literatura.O problema da modelação do comportamento de fluidos no interior deAmortecedores de Líquido Sintonizado, à semelhança do que acontece parareservatórios, é complexo, sendo apresentados os principais modelos matemáticos emecânicos utilizados na actualidade.Assim serão descritos modelos de comportamento adoptados no casoparticular dos Amortecedores de Líquido Sintonizado (TLDs) e modelos simplificadosde sistemas de 1 (SDOF) ou mais graus (MDOF) de liberdade com com os referidosdispositivos de mitigação de acções dinâmicas acopladosO presente relatório servirá, à semelhança dos relatórios Sistemas passivos,activos, híbridos e semi-activos: Estado dos conhecimentos, Actividade experimentalna área dos sistemas passivos para a protecção sísmica de estruturas: Experiência doNESDE e Modelos de comportamento dinâmico para fluidos no interior dereservatórios como uma das linhas orientadoras para o desenvolvimento dos trabalhospropostos no âmbito do PIP 2009-2012 do NESDE-DE Protecção Sísmica deEstruturas: Reabilitação, reforço e sistemas inteligentes.

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This Report corresponds to Task 2 of the NEFOREEE (New Fields of Research inEarthquake Engineering Experimentation) Project and comprises the description of theLNEC triaxial seismic platform and a presentation of the experimental programdeveloped in the scope of this Project.It is presented a description of the facility and the 3D seismic table with graphicalsupport, drawings of sizing and photographs, as well as its control system. The maininstrumentation available at the NESDE laboratory and used for this test is alsoincluded in this report.The model tested is described as well as the sequence of tests and the correspondingobtained results. Finally a brief analysis of the results is made.

O presente relatório final do projecto USuET integra o trabalho já apresentado norelatório de progresso de Sousa & Afonso [2007], nomeadamente no que toca aoscapítulos 2, 3 e parte do capítulo 4 e, adicionalmente, descreve, em detalhe, asactividades desenvolvidas no projecto desde a data desse relatório (secção 4.2, ecapítulos 5 e 6). A parte da investigação conducente à actualização do Simulador deCenários Sísmicos para ambiente WebSIG, aplicado ao Arquipélago dos Açores, não seencontra descrita com o mesmo detalhe, neste relatório, pois enquadra-se na tese demestrado em Sistemas de Informação Geográfica de Afonso [2007], submetida àUniversidade Técnica de Lisboa. A versão definitiva desta tese, cuja discussão se prevêainda em 2008, será enviada oportunamente.

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This report describes the second phase activity of the Portuguese group in the Precast Structures EC8 research project. The Portuguese group is composed by Laboratório Nacional de Engenharia Civil (LNEC) and the Civibral, S.A. precast company. This phase follows the shaking table tests of a 2 stories structure of the same precast system, which is commercialized by Civibral. More information about these tests can be found in the repor.The goal of the work presented in this document is to assess the seismic behaviour of column-foundation and beam-column connections from the same precast system. To help achieve this goal, 4 column-foundation and 10 beam-column connections were tested using quasi-static, monotonic and cyclic tests, which were made imposing displacements to the specimens. The column-foundation connections (CFC) can be categorized as socket connections and the beam-column connections (BCC) as dry connections using only mechanical devices to transmit forces between elements. All the specimens were supplied and mounted by Civibral personal.

Análise dos registos históricos de eventos climáticos e o seu impacto no setor da energia da AML, para identificar o grau em que este setor foi afetado por estímulos relacionados com o clima. Avaliação de capacidades adaptativas.

Análise da forma das edificações nas ações do vento

As condicionantes arquitetónicas e de urbanização na ventilação natural

Caracterização do vento. Ações sobre estruturas. Ensaios em túnel de vento