Seismic Dynamic Response Of Offshore Platforms

In offshore petroleum engineering,the design of offshore platforms has an important impact on the development of offshore oil.The platform is usually in a harsh marine environment and is subject to a variety of dynamic loads.Some dynamic loads can cause platform deformation.When the platform is subjected to loads such as earthquakes that are long lasting and highly destructive,there may be instability or cause structural damage,even the platform to collapse.It will also cause large-scale pollution to the marine environment.The response of the structure to wind loads and wavy loads is the main direction of offshore platform design research.However,there is less research on the seismic dynamic response of the structure.This paper is based on the seismic response spectrum method and time history method to analyze seismic dynamic response of jacket platform.First,the basic theory of response spectrum method is introduced in detail.Analysis of seismic dynamic response of a jacket platform using response spectrum method,to get the 6th order mode of the platform.The maximum response of the offshore platform under seismic action is obtained by SPRS method.Secondly,the basic principles of the time history method are introduced.Involving structural model selection and selection of seismic waves,etc.Then based on USFOS software,selected 4typical seismic time history records to analyze dynamic response of jacket-type offshore platform.Get some result such as,base sheer and overturning moment.Pile head force.At the same time,the main components of the platform are analyzed.Finally,it explores the criteria for checking the platform when the offshore platform is subjected to seismic in engineering practice,includes overall calibration criteria and parameter limits for the platform,and characteristics and standards of node check and pile check.Through an example to explored two methods for inputting different time history using different soil layers and inputting the same time history using different soil layers.Thus,different check results are obtained.