Portland State University. Department of Electrical and Computer Engineering
Lisa M. Zurk
Date of Award
Master of Science (M.S.) in Electrical and Computer Engineering
Electrical and Computer Engineering
1 online resource (xiv, 88 pages)
Piling (Civil engineering) -- Environmental aspects -- Columbia River, Marine animals -- Effect of noise on -- Columbia River, Underwater acoustics -- Mathematical models, Underwater acoustics -- Columbia River -- Measurement
Impact pile driving can produce extremely high underwater sound levels, which are of increasing environmental concern due to their deleterious effects on marine wildlife. Prediction of underwater sound levels is important to the assessment and mitigation of the environmental impacts caused by pile driving. Current prediction methods are limited and do not account for the dynamic pile driving source, inhomogeneities in bathymetry and sediment, or physics-based sound wave propagation.
In this thesis, a computational model is presented that analyzes and predicts the underwater noise radiated by pile driving and is suitable for shallow, inhomogeneous environments and long propagation ranges. The computational model uses dynamic source models from recent developments in the technical literature. Pile source models are coupled to a broadband application of the range-dependent acoustic model (RAMPE), a standard parabolic equation (PE) propagation code capable of modeling wave propagation through complex, range dependent environments. Simulation results are shown to be in good agreement with several observations of pile driving operations in the Columbia River between Portland, Oregon and Vancouver, Washington. The model is further applied to extend sound level predictions over the entire river and study the effects of sediment and bathymetry on the underwater sound levels present in the environment.
Laws, Nathan, "A Parabolic Equation Analysis of the Underwater Noise Radiated by Impact Pile Driving" (2013). Dissertations and Theses. Paper 1083.