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    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)
    Pein, Jonas von
    ;
    Lippert, Tristan
    ;
    Lippert, Stephan
    ;
    Estorff, Otto von
    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 Article
      16  105
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    Scaling offshore pile driving noise: Estimating the relevant sound pressure levels
    (2022-10)
    Pein, Jonas von
    ;
    Lippert, Tristan
    ;
    Lippert, Stephan
    ;
    Estorff, Otto von
    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 Paper
      31
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    Scaling laws for unmitigated pile driving: Dependence of underwater noise on strike energy, pile diameter, ram weight, and water depth
    (Elsevier, 2022-08-27)
    Pein, Jonas von
    ;
    Lippert, Tristan
    ;
    Lippert, Stephan
    ;
    Estorff, Otto von
    Sound 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 Article
    Scopus© Citations 5  98  220
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    Item type:Publication, Access status: without files ,
    Scaling offshore pile driving noise: examples for scenarios with and without a big bubble curtain
    (2022-06)
    Pein, Jonas von
    ;
    Lippert, Tristan
    ;
    Lippert, Stephan
    ;
    Estorff, Otto von
    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 Paper
      24
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    Scaling offhore pile driving noise : examples for scenarios with and without a big bubble curtain
    (International Commission for Acoustics (ICA), 2022-06)
    Pein, Jonas von
    ;
    Lippert, Tristan
    ;
    Lippert, Stephan
    ;
    Estorff, Otto von
    Publicationtype: Conference Paper
      52
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    Item type:Publication, Access status: without files ,
      20
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    Damped cylindrical spreading model: Estimation of mitigated pile driving noise levels
    (2021-12-15)
    Jestel, Jasmin
    ;
    von Pein, Jonas
    ;
    Lippert, Tristan
    ;
    Estorff, Otto von
    Underwater noise caused by impulsive pile driving for the installation of foundations for offshore wind farms is potentially harmful to marine life if not properly mitigated. Several models have been developed over the past years, to accurately predict the underwater sound field from pile driving activities. However, due to the complexity of the problem and subsequently the corresponding models, the use of such models is often restricted to a relatively small group of experts. To enable a wider group of people to estimate at least the sound exposure level (SEL), as one of the key quantities, the Damped Cylindrical Spreading (DCS) model has been developed recently and validated using measurement data from unmitigated pile driving. The paper at hand now aims at extending the DCS model to the case of mitigated pile driving noise, using corresponding measurement data from five offshore sites in the North Sea. Furthermore, the potential of the model to predict noise levels in close vicinity of the pile is investigated. Based on the available data sets, it is shown that the approach can indeed be extended to mitigated pile driving scenarios including short range levels as well as different noise mitigation techniques and foundation types, while still producing results that are more accurate than the currently most widely used approach for sound decay estimations.
    Publicationtype: Journal Article
      72
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    Validation of a finite element modelling approach for mitigated and unmitigated pile driving noise prognosis
    (2021-03-01)
    Pein, Jonas von
    ;
    Lippert, Stephan
    ;
    Estorff, Otto von
    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 Article
      69