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Item type:Publication, Access status: with files , Scaling laws for mitigated pile driving: dependence of underwater noise on strike energy, pile diameter, ram weight, water depth, and mitigation system(American Institute of Physics (AIP), 2024-09-01); ; ; Sound induced by impact pile driving is a possible risk to marine life. Therefore, it is common practice to use noise mitigation systems during piling to reduce the respective impact and to fulfill the prescribed noise limits. Scaling laws for the estimation of the underwater noise from unmitigated impact pile driving have been presented in von Pein, Lippert, Lippert, and von Estorff, "Scaling laws for unmitigated pile driving: Dependence of underwater noise on strike energy, pile diameter, ram weight, and water depth," Appl. Acoust. 198, 108986 (2022). This contribution shows how these scaling laws need to be changed if noise mitigation systems are considered. Scaling laws are developed for four different kinds of noise mitigation system setups. These include big bubble curtains, double big bubble curtain combinations, a fully absorbing system directly at the pile, and the combination of a system close to the pile and a double big bubble curtain. The derived scaling laws are verified and compared to publicly available measurement data.Publicationtype: Journal Article16 106 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Scaling offshore pile driving noise: Estimating the relevant sound pressure levels(2022-10); ; ; Underwater noise due to construction activities can reach sound pressure levels that are potentially harmful to the marine fauna. Percussive pile driving is the state-of-the-art installation technique for the foundations of offshore wind farms. The installation process leads to very high noise emissions. To protect the environment, limits have to be fulfilled for offshore pile driving noise in many countries. The assessment of the occurring sound pressure levels can be either done by numerical models or by simplified scaling methods. The scaling methods are especially useful at early stages of the planning phase, since a lot of input data that is necessary for the numerical models may not be available at that point. Within this contribution, the scalability of the relevant sound pressure levels such as the sound exposure level (SEL) and the peak sound pressure level (SPLpeak) is shown with and without the application of a big bubble curtain (BBC).Publicationtype: Conference Paper32 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: with files , Scaling laws for unmitigated pile driving: Dependence of underwater noise on strike energy, pile diameter, ram weight, and water depthSound produced by marine pile driving activities poses a possible risk to marine life. The assessment and mitigation of this risk requires a prediction of the expected sound levels. While different analytical models have been presented to estimate the decay characteristics of pile driving noise, the estimation of the source level still requires the use of numerical modelling in most cases. The paper at hand discusses the possibilities and limits of estimating approximate source or any other levels by scaling laws, using measurement data from previous projects. The identified main influencing factors include strike energy of the hammer, pile diameter, ram weight, and water depth. The scaling laws are derived from theoretical considerations verified against results of a state-of-the-art finite element model for pile driving noise radiation. The found dependencies are then validated against a set of offshore measurement results. It is shown that the obtained scaling laws provide an option to approximately estimate the sound exposure levels of pile driving activities from one site to the other, within practical ranges of accuracy.Publicationtype: Journal ArticleScopus© Citations 5 98 224 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Scaling offhore pile driving noise : examples for scenarios with and without a big bubble curtain(International Commission for Acoustics (ICA), 2022-06); ; ; Publicationtype: Conference Paper52 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Scaling offshore pile driving noise: examples for scenarios with and without a big bubble curtain(2022-06); ; ; For the installation of offshore wind turbines, large pile foundations are driven into the seabed. The pile driving process can lead to high sound pressure levels in the water column. These levels can reach magnitudes that are potentially dangerous for the marine fauna. Therefore, in many countries the emitted sound pressure levels have to comply with limit values in order to protect the marine environment. Noise mitigation measures are usually necessary to fulfill these limits. Prior to wind farm construction, complex numerical models are often applied for a precise prediction of the occurring sound pressure levels to be expected. In order to allow a simplified first estimation even without such detailed calculation models, scaling laws provide an alternative approach. Within this contribution, already existing scaling laws for unmitigated pile driving are updated for scenarios including a big bubble curtain. The sound exposure levels of six different sites are estimated applying scaling laws for unmitigated and mitigated pile driving noise and compared to the actual measurements.Publicationtype: Conference Paper24 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Skalierungsgesetze für Offshore-Rammschall: Ein Anwendungsbeispiel zur Bestimmung der auftretenden Unterwasser-Schallpegel(2022-03); ; ; Publicationtype: Conference Paper20 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Validierung eines 3D-Rammschall-Modells unter Berücksichtigung unterschiedlicher Schallschutzsysteme(2021-08); ; Publicationtype: Conference Paper45 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Validation of a finite element modelling approach for mitigated and unmitigated pile driving noise prognosis(2021-03-01); ; Piles are the state-of-the-art foundation type for offshore structures like offshore wind turbines. The pile driving process induces high sound pressure levels into the water, which are potentially harmful for the marine environment. To protect the marine life, regulations for these levels apply in many regions of the world. Therefore, detailed pile driving noise models are necessary to allow for both a prognosis of the underwater noise levels and the dimensioning and optimization of possible noise mitigation systems. In this paper, an established model based on a finite element approach is validated by means of three measurement campaigns. These have been conducted at different sites in the North Sea and include piling with and without noise mitigation measures. The noise mitigation systems are modelled as fully absorbing by applying a mixed Dirichlet-Neumann boundary condition at its position. Therefore, the computational results with noise mitigation measures are generally below the measured data and present the highest achievable noise reduction. The measurement campaigns have been conducted with a big bubble curtain and a noise mitigation screen. The occurring differences between the modelled and measured results with and without noise mitigation are shown.Publicationtype: Journal Article69 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Validation of a 3D pile driving noise model with noise mitigation measuresPiles are the state-of-the-art foundation for offshore wind structures. The piling process leads to high sound pressure levels in the water reaching levels that are potentially harmful to the marine life. Numerical models are used to predict the sound pressure levels and to optimize the sound mitigation set-up prior to construction. Such models are often based on a hybrid modelling approach with a close-range and a far- range model. Thereby, the close-range model is used to derive the starting field for the far-range model. Often, the close-range model is based on the finite element method (FEM). Far-range models usually use underwater acoustics propagation models such as the parabolic equation (PE) modelling approach. Within this contribution, a hybrid three-dimensional (3D) pile driving noise model is validated with measurement data from offshore sites with a dedicated bathymetry. The model is based on a FE modelling approach for the close-range and a 3D PE model for the far-range. The measurements were conducted with two different noise mitigation measures. The method of including these measures into the PE model as well as the influence of bathymetry-induced 3D effects on the sound pressure levels are presented.Publicationtype: Conference Paper48 - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Access status: without files , Pile driving noise: general setup and capability of state-of-the-art prediction models in 2D and 3D(2019-10-17); ; Publicationtype: Conference Paper73