Welcome to LNEC's Scientific Repository
Recent Submissions
This document presents the Data Management Plan (DMP) for the MOSAIC.pt project. MOSAIC.pt has chosen to participate in the Open Research Data pilot from FCT. Following the recommendations provided by the European Commission (EU, 2016), in the scope of making data FAIR, this Data Management Plan (DMP) provides the approach to the following topics: • the handling of research data during and after the end of the project; • what data will be collected, processed and/or generated; • which m...
Dams have practically been around since human civilization. While modern dams are built for hydroelectric purposes, ancient dams were built to flood prevention and water irrigation providing. In the past, the sparse knowledge on hydrology, soil mechanics and on structures analysis made the waterworks development to be based on empirical methods. Because of this, most of the dams were constructed indiscriminately with earth and rock, with no slope protections and were not provided with safety ...
A firma MONESTORIL – Investimentos Lda. solicitou a este Laboratório Nacional o desenvolvimento de um estudo de garantia da qualidade que promovesse a correta gestão da qualidade do processo de instalação das janelas exteriores e do condicionamento acústico do edifício da Av. Saboia nº 123, em Cascais. O presente documento tem por objetivo certificar, não só a realização pelo LNEC do estudo de garantia da qualidade mencionado, mas também a eficácia dos resultados obtidos com a sua implementaç...
This paper presents a study of the effect of a superabsorbent polymer (SAP) for autogenous shrinkage control on the uniaxial tensile behavior of steel fiber reinforced concrete (SFRC). The use of fibers and SAP potentially increases the durability of the concrete, preventing cracking by autogenous shrinkage and enhancing post-cracking behavior. Furthermore, SAP can provide further hydration for self-healing purposes and improve the ductility of the SFRC. In order to evaluate the effect of the...
O projeto de I&D SINERGEA visa criar uma plataforma inteligente e inovadora de suporte à gestão integrada e otimizada da energia, da qualidade da água balnear e da inundação em cidades costeiras. Enquadrada no paradigma “cidades inteligentes”, esta plataforma permitirá, em simultâneo: 1) contribuir para a eficiência energética das cidades, através de estratégias integradas de minimização do consumo de energia das infraestruturas de drenagem; 2) proteger a utilização das zonas balneares u...
To upgrade the response capability to coastal flood events, hazard predictions need to be improved through integrating the effect of the coastal morphological variability in the nearshore-foreshore-backshore hydromorphological processes induced by waves-tide-wind-atmospheric pressure. In order to evaluate the short-term morphological response of different coastal typologies to potential flood conditions (spring high tide level, storm surge, high wave height), field data acquired in 2019 in th...
O LNEC encontra-se a apoiar o Ministério da Defesa Nacional (MDN) num conjunto de questões técnico-ambientais relacionadas com a presença, nos últimos 60 anos, do contingente da Força Aérea Americana (USAFE) na Base das Lajes, ilha Terceira. Nesse contexto, o LNEC procedeu à caracterização adicional de um conjunto de locais. Neste relatório apresentam-se os trabalhos desenvolvidos e a análise dos resultados obtidos a SE do Site 5001, com base em prospeção geofísica, assim como na avaliação da...
Atualmente, o controlo da segurança de grandes barragens de betão tende a apoiar-se em sistemas de monitorização com Recolha Automática de Dados (RAD), incluindo a medição de grandezas para caracterização da resposta sob ações dinâmicas, em que é necessário utilizar altas frequências de amostragem, em geral da ordem de 50 Hz ou superiores. No caso da barragem do Cabril, por exemplo, o LNEC e a EDP instalaram, em 2008, um sistema para monitorização da resposta da obra sob ações sísmicas e sob ...
No âmbito da assessoria técnica para a "Análise e acompanhamento dos trabalhos de reabilitação para melhoria da situação ambiental envolvente aos furos de abastecimento de água do concelho de Praia da Vitória, Açores", que o LNEC tem vindo a prestar à Entidade Reguladora dos Serviços de Águas e Resíduos dos Açores (ERSARA) desde 2012, o presente contrato, CON-ERSARA/2019/3, visa dar seguimento ao estudo que vem sendo desenvolvido. Neste relatório apresenta-se uma análise dos resultados obtido...
The seismic response of a 290 m high arch dam, located in a high seismicity zone in China, is studied in this paper. The goal is to evaluate the influence of the reservoir water level on the dam’s seismic behaviour. The numerical simulations are carried out using the 3DFE program DamDySSA3.0, developed in LNEC for linear dynamic analysis of dams, including a module for seismic analysis under applied base accelerations. The problem is solved by a Finite Element coupled formulation in displacem...
Neste trabalho efetuam-se estudos de simulação numérica da resposta sísmica de uma grande barragem abóbada, considerando uma dada lei de amortecimento de Rayleigh com vista a analisar a influência da cota da albufeira. A modelação do sistema barragem-fundação-albufeira é efetuada com um modelo coupled, baseado numa formulação em deslocamentos e pressões, que permite simular a interação dinâmica barragem-albufeira considerando a propagação de ondas de pressão na albufeira. A discretização do s...
The BINGO Project is a Horizon 2020 project, with the goal of evaluating climate change and its impacts on the water cycle in the short range (2015 to 2024). Such evaluation is the basis for risk analysis and this analysis supports the creation of an actionable adaptation actions’ portfolio, able to be replicated in other areas beyond those of the 6 case studies belonging to this project. The whole hydrological cycle was analysed for climate change impacts and, in the Portuguese case study is...
Nowadays, the management and safety control of large dams is generally based on automatic monitoring, including the socalled seismic and structural health monitoring systems (SSHM), using the latest technology for automatic data measurement, acquisition and transmission. These systems should include software for automatic management and analysis of continuous monitoring data and software for numerical simulation of the dam dynamic behavior using 3D finite element models. This software should ...
This paper is focused on the LNEC experience regarding the development and operation of continuous vibrations monitoring systems in large concrete dams. The goal is to emphasize the importance of the combined use of monitoring data and numerical models for Seismic and Structural Health Monitoring (SSHM) of Dams. The SSHM system installed in Cabril dam (132 m high), in operation since 2008, is described. The design and implementation of this system, including hardware and software, was the res...
This paper is focused on the Portuguese experience regarding the development and operation of continuous vibrations monitoring systems in large concrete dams. The goal is to emphasize the importance of the combined use of monitoring data and numerical models for Seismic and Structural Health Monitoring (SSHM) of Dams. The case study is Cabril arch dam (132 m high), the highest dam in Portugal, in which a pioneer SSHM system has been in operation since 2008. This system, installed by LNEC, was...
This paper focuses on studying the dynamic behaviour of large dams over time, including identification of modal parameters (natural frequencies, modal damping ratios and mode shapes) and seismic response analysis, based on measured acceleration time histories. A comparison between experimental results obtained from continuous vibration monitoring data and numerical modelling results from 3D FE models is presented. The aim is to emphasize the interest of combining the use of recorded data from...
This chapter is focused on the Portuguese experience on the development and exploration of systems for continuously monitoring dam vibrations, using accelerometers. The pioneer system for seismic and structural health monitoring (SSHM) installed in Cabril dam (the highest Portuguese arch dam: 132 m high) is described in detail. The design of this system was the result of a long-term LNEC research program, still ongoing. These monitoring systems should include software developed to automatical...
The safety control of dams under operation is based on the comparison between observed data, from monitoring systems, and numerical data from mathematical models developed to simulate/predict the dam behaviour over time. For the direct analysis of observed data semi-statistical models for effects separation are usually adopted, namely of the type HST or HSCT. For dam behaviour simulation/prediction Finite Element Method (FEM) models, based on the fundamental equations of structural mechanics,...
LNEC's Scientific Repository
The LNEC Scientific Repository has the purpose of publicizing and allowing free access to the scientific production of its research community in the fields of civil engineering and related areas, promoting the sharing and visibility of scientific information and assuring the preservation of the institution's intellectual memory.
Communities in DSpace
Choose a community to browse its collections.
Discover
- 3568 2010 - 2020
- 1188 2000 - 2009
- 730 1990 - 1999
- 550 1980 - 1989
- 325 1970 - 1979
- 206 1960 - 1969
- 81 1951 - 1959