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G. Reuver:
"Evaluation of vibratory pile installation effects on adjacent buried pipe structures through a coupled analytic approach";
Supervisor: M. Hicks, P. Vardon, C. Kasbergen, A. Ramkisoen, D. Adam, P. Nagy; Delft University of Technology, Faculty of Civil Engineering and Geosciences, 2016; final examination: 2016-05-25.

Urban areas in the Netherlands are expending rapidly and civilization is squeezed onto a decreasing space. As a result building projects intent to be located very close to adjacent constructions leading to potential risk damaging these structures. Especially structures that are constructed within the subsurface, like cables and ducts, require extra care. A fundamental challenge in engineering of vibratory pile installation methods is to quantify the vibration levels and wave propagation through the subsurface. Using empirical predictionmethods, based onmeasured field data, the complexity of the problem lacks authenticity. No distinction between different wave types or layered soil is taken into consideration. These crude methods are good "first prediction methods", but lack the validly with respect to the impact on pipe structures present in the subsurface. Cost expensive precautionary measurements or time expensive 3D Finite Element calculations are in directly related to the complexity of the problem statement. The need for a reliable and simple to use prediction method is the fundamental basis for thisMaster Thesis research project.
Basic dynamics is mandatory to retrieve knowledge about the complexity of the problem spectrum. Various wave properties and behavior are therefore included in the investigation to obtain favorable judgment in modeling choice. Massarsch and Fellenius [80] proposed a simplemodel for the prediction of vibration levels at the surface induced by impact pile installation will be applied. This mothodology makes it possible to investigsted layer soil compositions and makes a clear distinction between different wave types. Investigation of vibratory pile installation problems, as carried out in this Master Thesis project, requires modification of this model. To prove the validity of the modified research methodology, the Eurocode 3 [2] and the application of an axis symmetric 2D Finite Element ABAQUS model is inserted as comparison method.
The pressure wave as modeled enforces the pipe to vibrate. Modeling the impact of this oscillations on pipe structures by means of a 1D Finite Element approach is in accordance with the aim for simplification and model authenticity. The constitutive behavior of the model is build on the Euler-Bernoulli beam theory and applied to the equation of motion. A realistic soil damping representation is incorporated by means of the Rayleigh-dampingmethod.
A parameter sensitivity study is applied to test all individual model components on their behavior with respect to condition changes. From the study can be concluded that the coupled modified vibration estimation method of Massarsch and Fellenius [80] (named Wave Propagation Model in this research) to the proposed pipe structure representation (named Pipe Structure Model in this research) made it possible to accomplish the research goals of this Master Thesis project. The most important research goal achieved is the possibility to predict the oscillatory behavior of the pipe to enforced vibration waves from vibratory sheet pile installation. Although the comparison between the Wave Propagation Model and the ABAQUS model show complementary results, due to the the lack of observation regarding fieldmeasurement data the authenticity of the model is not yet confirmed.

pipe structures, vibration, wave propagation,

http://publik.tuwien.ac.at/files/publik_250924.pdf