Effects of foundation damage and water-level change on vibration modal parameters of gravity-type caisson structure  

作　　者：LEE So-Young KIM Jeong-Tae 

机构地区：[1]Department of Ocean Engineering, Pukyong National University

出　　处：《Science China(Technological Sciences)》2015年第2期316-329,共14页中国科学（技术科学英文版）

基　　金：supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry ofEducation,Science and Technology(Grant no.NRF-2013R1A1A2A10012040);the financial support of the project Development of Inspection Equipment Technology for Harbor Facilities funded by Korea Ministry of Land,Transportation,and Maritime Affairs

摘　　要：In this paper,the effects of foundation damage and water-level change on vibration characteristics of gravity-type caisson structure are examined by analyzing modal parameters extracted from output-only information.To achieve the objective,the following approaches are implemented.Firstly,vibration response analysis methods are selected to estimate power spectral density and modal parameters such as natural frequency,damping ratio and mode shape of a lab-scale caisson structural system.Secondly,vibration tests on the lab-scale caisson system are performed under a series of test scenarios which include three water-level changes and three damage levels.Thirdly,experimental modal parameters corresponding to the damaging cases as well as the water level cases are extracted by frequency domain decomposition method and stochastic subspace identification method.Finally,the effects of the water-level variation and foundation damage on the extracted modal parameters are examined to assess the feasibility of the vibration-based damage detection in gravity-type caisson structures under water-level uncertainty.

关 键 词：caisson structure gravity-type structure modal parameter effect of water-level foundation damage 

分 类 号：U656.2[交通运输工程—港口、海岸及近海工程]