This thesis investigates vibration transmission during \ac{vp} with a focus on risks to the lifting equipment. The work is motivated by incident reports and by the absence of field measurements on cranes during offshore operations. The study aims to identify resonance frequency(ies), quantify component displacements, determine forces in the hoist cable, and characterize how each component responds across the input frequency range. A secondary aim is to relate frequencies that favor pile penetration to potential risks for the crane.

A two stage modeling approach is adopted. First, the crane is generalized to a \ac{2d} form and converted to a \ac{1d} system of lumped masses and linear springs aligned vertically. The pedestal is idealized as fixed. Linear behavior and small displacements are assumed. Second, the \ac{mp} is modeled in Ansys with shell elements to capture flexible body behavior. A mode reduction retains only axial modes of the \ac{mp}, since bending, torsion, and circumferential shell modes do not directly couple to the vertical vibration path that governs \ac{vp}. Depth dependent stiffness and damping represent the soil at the toe. Hoist stiffness varies with depth through cable length.

The calculation method separates free and forced vibration. In free vibration, the system eigen-problem provides resonance frequency(ies) and mode shapes with the \ac{mp} first treated as rigid. The axial flexible body natural frequency of the \ac{mp} is then obtained from the shell model. In forced vibration, the harmonic response is computed to obtain frequency response functions and absolute displacement magnitudes for the components, as well as the hoist cable force.

Results show two frequency families that govern the response. The first family contains the system resonance frequency(ies) with a rigid \ac{mp}. The second family contains the axial flexible body natural frequency of the \ac{mp}. Modes 1, 2, and 4 are largely insensitive to \ac{mp} flexibility. Mode 3 and the axial flexible body frequency depend strongly on the soil stiffness at the toe and shift with depth. Within the operational range of the \ac{vh}, the fourth system resonance and the first axial flexible body frequency of the \ac{mp} lie close together and can interchange order as depth changes.

The harmonic response clarifies component participation at key frequencies. Near Mode 3, motion concentrates in the exciter and \ac{mp} and engages the soil stiffness most strongly. Near Mode 4, the lower block and bias mass dominate while the \ac{mp} response is limited. At the axial flexible body frequency of the \ac{mp}, the head and toe move in opposite directions with a near stationary point along the pile length, consistent with a fundamental axial mode. These behaviors explain the locations and amplitudes of the observed peaks.

A verification step compares boom tip response and hoist cable force between the simplified system and the full \ac{fe} crane. The first peak aligns in both models, supporting the validity of the simplified representation for global behavior. Differences at higher frequencies are traced to flexible crane substructures that the simplified model does not include. This comparison establishes where the simplified model is reliable and where detailed crane is more suitable for cranes structure fatigue study.

Mitigation is explored conceptually. Removing the hoist load path would eliminate force transmission into the boom, but this is often impractical. Introducing an isolator between the lifting equipment and the piling equipment is a more practical option. When tuned near the axial flexible body frequency of the \ac{mp} and near the fourth system resonance, an isolator can reduce force transmission into the boom while preserving penetration performance.

The study concludes that frequencies that favor penetration can occur near frequencies that amplify responses in the lifting equipment. Managing this close proximity requires attention to frequency modes, awareness of depth effects through soil stiffness, hoist force fluctuations, and consideration of isolation in the load path. The work provides a structured method to identify critical frequencies, quantify responses, and separate the roles of monopile flexibility and crane structure, while pointing to targeted measurements and modeling extensions that would complete a validated framework for decision making.