A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Time simulation of aerodynamic response of long-span bridges to turbulent wind
Abstract An efficient computational procedure is developed for time simulation of buffeting and flutter response of suspension bridges. The structural model is reduced by quasi-static condensation leading to a typical 1:5 reduction of the number of dynamic degrees of freedom. The turbulent wind field is represented by a convected fully three-dimensional velocity field and simulated by an auto-regressive procedure in which the coefficients are determined explicitly from conditional mean values and variances in the convected field. This procedure permits free choice of the simulation points – typically the nodes of the structural model. The convection concept can include translation of a fully three-dimensional nodal lay-out, e.g. the double set of main cables and hangers. The wind field representation is a generalized orthotropic representation of the von Kàrmàn velocity spectrum. This implies that the coherence functions contain a length scale in addition to the traditional non-dimensional frequency, reducing the coherence at large separations and thereby the fluctuating response of long suspension bridges. The aerodynamic forces are represented by a compact rational representation which is included in a momentum based time integration procedure which allows a fairly detailed tailoring of structural and algorithmic damping. The procedure is sufficiently general to permit response analysis of the full bridge structure with two layers of cables, but examples demonstrate rather small effects on the lower modes from the wind load on the cables.
Highlights Efficient model for direct computation of time domain response of long-span bridges subjected to turbulent wind. Wind turbulence based on a fully three-dimensional orthotropic full field representation, simulated as convected turbulence by an explicit sequential conditional mean field procedure with free layout of simulation points. Reduction of structural model by quasi-static condensation, leading to significant size reduction of the wind field simulation, the structural model and the aero-elastic representation. Second order momentum-based time integration of aero-dynamic system with energy balance reproduction and optional algorithmic high-frequency dissipation.
Time simulation of aerodynamic response of long-span bridges to turbulent wind
Abstract An efficient computational procedure is developed for time simulation of buffeting and flutter response of suspension bridges. The structural model is reduced by quasi-static condensation leading to a typical 1:5 reduction of the number of dynamic degrees of freedom. The turbulent wind field is represented by a convected fully three-dimensional velocity field and simulated by an auto-regressive procedure in which the coefficients are determined explicitly from conditional mean values and variances in the convected field. This procedure permits free choice of the simulation points – typically the nodes of the structural model. The convection concept can include translation of a fully three-dimensional nodal lay-out, e.g. the double set of main cables and hangers. The wind field representation is a generalized orthotropic representation of the von Kàrmàn velocity spectrum. This implies that the coherence functions contain a length scale in addition to the traditional non-dimensional frequency, reducing the coherence at large separations and thereby the fluctuating response of long suspension bridges. The aerodynamic forces are represented by a compact rational representation which is included in a momentum based time integration procedure which allows a fairly detailed tailoring of structural and algorithmic damping. The procedure is sufficiently general to permit response analysis of the full bridge structure with two layers of cables, but examples demonstrate rather small effects on the lower modes from the wind load on the cables.
Highlights Efficient model for direct computation of time domain response of long-span bridges subjected to turbulent wind. Wind turbulence based on a fully three-dimensional orthotropic full field representation, simulated as convected turbulence by an explicit sequential conditional mean field procedure with free layout of simulation points. Reduction of structural model by quasi-static condensation, leading to significant size reduction of the wind field simulation, the structural model and the aero-elastic representation. Second order momentum-based time integration of aero-dynamic system with energy balance reproduction and optional algorithmic high-frequency dissipation.
Time simulation of aerodynamic response of long-span bridges to turbulent wind
Møller, Randi N. (author) / Krenk, Steen (author) / Svendsen, Martin N. (author)
2019-12-10
Article (Journal)
Electronic Resource
English
Response analysis of long-span bridges for turbulent wind
| British Library Conference Proceedings | 1994
Aerodynamic Effect of Non-uniform Wind Profiles for Long-Span Bridges
| Springer Verlag | 2019
Coupled aeroelastic and aerodynamic response analysis of long-span bridges
| Online Contents | 1996
Coupled aeroelastic and aerodynamic response analysis of long-span bridges
| British Library Conference Proceedings | 1996
Modeling and simulation of aerodynamic in long span suspension bridges
| British Library Conference Proceedings | 2005