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Traditional dam safety methods, based on visual inspections and manual monitoring, have long been the standard for ensuring the stability and safety of dams. However, as the scale and complexity of dam projects have increased, these methods have become increasingly insufficient. Major limitations of traditional dam safety methods are the existence of deficient observation plans and the potential for human error. Inspectors may miss crucial signs of deterioration or failure, and manual monitor...

Most gravity dam failures occur due to sliding along the dam/foundation interface, rock mass discontinuities, or rock mass layers of lower strength. The possibility of sliding of a dam is usually evaluated based on simplified limit equilibrium techniques. In this study an explicit time-stepping small displacement algorithm, Parmac2D-Fflow, is used to assess the safety of gravity dams. This algorithm is based on a discrete representation of discontinuities, simulates the hydro-mechanical inter...

Evaluation of the sliding stability of concrete dams requires the use of numerical tools not only able to simulate the coupled hydromechanical behavior but also able to adequately represent the foundation discontinuities and the specific features of dam foundations. The formulation of a three-dimensional (3D) small displacement finite element model based on interface elements to simulate the discontinuities is presented. In this model, the hydraulic behavior is simulated assuming that the wat...

Stone masonry walls are the main structural elements of many historic buildings. Their restoration and preservation are a major concern given the increasing interest in the rehabilitation of built historical heritage and the implementation of preventive measures to mitigate seismic risk. The accurate structural assessment of the existing rubble stone masonry is a very complex and difficult task, due its composite and complex nature. The heterogeneity and uncertainty in material properties of ...

A codificação das normas técnicas da construção (NTC), prevista desde 1999 no Regime Jurídico da Urbanização e da Edificação, não foi ainda concretizada, devido aos múltiplos desafios que coloca. A codificação representa também uma oportunidade para realizar uma reforma estrutural do quadro legal e regulamentar da construção. Com o objetivo de apoiar o processo de codificação, foi desenvolvido no Laboratório Nacional de Engenharia Civil um estudo de investigação para sistematizar e aprof...

Micromechanical modelling through the Discrete Element Method (DEM) is adopted for the study of bituminous materials given its capability to replicate complex microstructures behaviour. Typically, DEM models of bituminous materials consist of an assembly of randomly distributed spherical rigid particles which interact using elastic and/or simple viscoelastic contact models, and individual aggregates are represented by single particles. However, recent years have witnessed a notable surge in r...

The integration of healing capsules into asphalt mixtures has demonstrated promising advancements in their intrinsic self-healing properties. However, the efficacy of this technology still requires further investigation. Rigid particle models, utilizing the discrete element method (DEM), have been adopted to simulate the creep, fracture, and viscoelastic behavior of asphalt mixtures, accounting for their irregular microstructure and particle contacts. This study utilizes the previously develo...

A avaliação estrutural das paredes de alvenaria de pedra tradicional é uma tarefa complexa devido à heterogeneidade e incerteza nas propriedades dos materiais constituintes, argamassa e pedra, e à variabilidade do posicionamento e geometria destes elementos na alvenaria. Nesta comunicação, modelos experimentais de alvenaria de pedra (muretes), construídos de acordo com técnicas tradicionais portuguesas, ensaiados experimentalmente sob condições de carregamento em compressão-corte, são avaliad...

he current first generation of Eurocodes is a suite of ten Euro-pean standards for the design of buildings and civil engineeringworks, whose implementation started in 2010. EN 1990 sets thebasis of structural design, with the other Eurocodes dealingwith different materials and specific aspects of design. Geo-technical aspects of design are covered by EN 1997 “Geotech-nical design”, usually called Eurocode 7. The evolution of the Eurocodes started in 2012 and the main ob-jectives of their rev...

O presente trabalho insere-se no âmbito de um protocolo entre o Instituto da Mobilidade e dos Transportes, I.P. (IMT) e o Laboratório Nacional de Engenharia Civil (LNEC) e consiste no relatório de ponderação do processo de consulta pública a que foi sujeito o documento normativo para aplicação a arruamentos urbanos, recentemente concluído.

A conjugação entre os modelos numéricos e os resultados observados do comportamento das obras é uma ferramenta fundamental no apoio ao controle de segurança de grandes obras. A barragem do Baixo Sabor possui um sistema de monitorização dinâmica em continuo, e foram realizados dois ensaios de vibração forçada para duas cotas de albufeira. Neste contexto foram desenvolvidos modelos numéricos da barragem do Baixo Sabor incorporando o conjunto barragem-fundação-albufeira. Neste artigo, apresentam...

A avaliação da resposta dinâmica das obras e o acompanhamento da evolução do seu comportamento durante as várias fases da vida é muito importante, estando inserida nas atividades do controle de segurança estrutural. A barragem do Baixo Sabor possui sistemas de monitorização dinâmica em continuo e sísmica, tendo sido realizados dois ensaios de vibração forçada para duas cotas de albufeira. Foram desenvolvidos modelos numéricos incorporando o conjunto barragem-fundação-albufeira, calibrados com...

The Baixo Sabor dam is a 123 meters high concrete arch dam located in the north of Portu-gal. After the performance of a forced vibration test, a quite unique experimental programme was initiated in the dam during the first filling of the reservoir, with the installation of a con-tinuous dynamic monitoring system in December 2015. The implementation of such a system aimed to study the evolution of the dam’s dynamic behaviour during the first filling, as well as to monitor its condition in the...

The dam’s reservoir water level varies over the year according to the water inflow and outflow, as a function of environmental events but also of dam exploitation management policy and human decisions. In the Portuguese dam safety regulation (RSB 2007), the normal water level (NWL) is considered as the optimum exploitation level. However, as proved by the continuous monitoring over the lifetime of a set of dams, the NWL is occasionally exceeded for non-negligible time periods. The reservoir w...

One concern of the dam surveillance activities is the assessment of the real structural behaviour, to detect possible malfunctions early. For real-time decision be effective, there must be confidence in the measured data, and it must be possible to interpret the data (through adequate data-based methods) in order to properly assess the structure's behaviour and condition (based on reliable numerical models). In the actual context, the main threats are the inability to detect in a timely manne...

The main purpose of assessment of dam condition, through the use of the infor-mation provided by the monitoring system, is achieved by having up-to-date knowledge of the dam. Early anomalous behaviour detection is expected in order to allow appropriate intervention to correct the situation or to avoid serious consequences. Once a dam is in its operation phase, the assessment of the dam's condition and the interpretation of the dam's behaviour are supported by data-based models, among others, ...

Tirando partido das medições do sistema de observação de uma barragem de betão, registadas automaticamente com frequência horária, é possível realizar-se um estudo para avaliar o efeito da frequência de medição na qualidade dos modelos de Machine Learning utilizados para a previsão expedita do comportamento observado em barragens de betão. Para tal, foram criados subconjuntos desses valores com diferentes frequências, como diárias, semanais ou quinzenais, com o intuito de simular cenários de ...

This paper describes the study of the metrological quality of the excitation force in the context of force vibration test of concrete dams. For this purpose, a measurement uncertainty evaluation was performed, based on available probabilistic information about the input quantities – rotation frequency, mass, radial position, dimension, diameter and density of the generator’s rod – which support the determination of the excitation force in an eccentric masses vibration generator, used by LNEC ...