TADEU , Antònio

This paper proposes a novel boundary element approach formulated on the Bézier–Bernstein basis to yield a geometry-independent field approximation. The proposed method is geometrically based on both computer aided design (CAD) and isogeometric analysis (IGA), but field variables are independently approximated from the geometry. This approach...

This paper proposes an enhancement of the treatment of non-homogeneous boundary conditions to improve the boundary element method (BEM) formulation. The standard formulation is modified by introducing the boundary conditions in the integral kernels. The boundary conditions are implicitly defined through known parameters depending on the...

This work presents a two-and-a-half dimensional (2.5D) spectral formulation based on the finite element method (FEM) and the boundary element method (BEM) to study wave propagation in acoustic and elastic waveguides. The analysis involved superposing two dimensional (2D) problems with different longitudinal wavenumbers. A spectral finite...

This paper proposes a novel boundary element approach formulated on the Bézier-Bernstein basis to yield a geometry-independent field approximation. The proposed method is geometrically based on both computer aid design (CAD) and isogeometric analysis (IGA), but field variables are independently approximated from the geometry. This approach...

This paper presents a novel formulation of two spectral elements to study guided waves in coupled problems involving thin-walled structures and fluid-acoustic enclosures. The aim of the proposed work is the development of a new efficient computational method to study problems where geometry and properties are invariant in one direction,...

This work presents a two-and-a-half dimensional (2.5D) spectral formulation based on the finite element method (FEM) and the boundary element method (BEM) to study wave propagation in acoustic and elastic waveguides. The analysis involved superposing two dimensional (2D) problems with different longitudinal wavenumbers. A spectral finite...

In this paper, we propose a spectral element method (SEM) to study guided waves in coupled problems involving thin-walled structures and fluid-acoustic cavities. The numerical method is based on the subdomain decomposition of the fluid-structure system. Two spectral elements are developed to represent the fluid and the structure. A plate...

This paper presents a numerical method based on a two-and-a-half dimensional (2.5D) boundary element-finite element (BEM-FEM) coupled formulation to study noise and vibration from underground structures. The proposed model properly represents the soil-structure interaction problem and the radiated noise and vibration. The soil is modelled with...

This paper describes a general approach to compute the boundary integral equations that appear when the boundary element method is applied for solving common engineering problems. The proposed procedure consists of a new quadrature rule to accurately evaluate singular and weakly singular integrals in the sense of the Cauchy Principal Value by...

The efficiency of two coupling formulations, the boundary element method (BEM)-meshless local Petrov–Galerkin (MLPG) versus the BEM-finite element method (FEM), used to simulate the elastic wave propagation in fluid-filled boreholes generated by a blast load, is compared. The longitudinal geometry is assumed to be invariant in the axial...

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 angles of attack between −8° and +8°. The simulations were performed by solving the steady-state Reynolds averaged Navier-Stokes (RANS) equations...

This work validates the simplified theoretical, analytical and numerical models used in the preliminary design stage of the 516 Arouca footbridge over the River Paiva (Portugal), the world's longest suspension footbridge. The models were used to define the configuration of the bridge under static loading and the eigenfrequencies excited under...

This paper investigates the vibrations induced by humans through in situ behaviour tests of the 516 Arouca footbridge (Portugal), the world's longest span in 2020 (516 m). The study consists of in situ experimental tests in which the structure was subjected to wind and pedestrian loads. The bridge is first described, to provide design and...

Modular steel bridges are structures whose construction is based on regular prefabricated truss units. This presents several advantages, such as rapid and easy deployment, high adaptability to the terrain and reduced construction costs. However, they generally face operational restrictions for span lengths greater than 60 m. Recent...