A modal analysis of bucket foundation breakwater based on the Lanczos method

The bucket foundation breakwater is a new type of structure applied in port and coastal engineering, the stability of which is sustained by the bucket foundation penetrated in soft soil. According to the project of extending breakwaters in Tianjin Port, a three-dimensional finite element model is developed and used in modal analysis based on the Lanczos method. It is resulted that the movement modes of this new type of structure in soft soil foundation in the previous modals are mainly described as the displacement along horizontal direction, the movement up and down along vertical direction and the rotation round a point under the bucket; the longest natural period of vibration of the system is far away from the external excitation wave force period, so the structure will not be instable for resonance under the dynamic wave load.