Deepwater Jackup Dynamic Response Analysis And Structure Optimization Research

In recent years, with the development of deep sea petroleum exploration, oceanengineering has gradually become a hot spot in the study of direction. Study of deepwaterJack-up drilling platform, breaking the monopoly of foreign technology to form productswith independent intellectual property rights, are important.Aiming at the a certain type oftruss leg deep jack-up drilling platform, focus on the static and dynamic characteristics ofthe whole, and the jack-up platform structure optimization, to improve the jack-up platformdesign ability has important significance. This paper studies the main content includes:1. This paper expounds the basic idea of the finite element method and the basicconcept, and introduces the jack-up platform nonlinear dynamic analysis method. By usingnonlinear wave theory Stokes five order wave theory and Morison formula, theenvironmental load of wave load calculation method.2. Using APDL language build parameterized geometric model and the finite elementmodel. Including the jack-up platform ship deck, leg structure and hull and deck connectionmode of numerical simulation.Through ANSYS software static calculation and analysis,Simulated respectively from the storm deposit and normal operation conditions of jack-upplatform work state, studying the statics characteristic.3. Using Block Lanzcos method get jack-up platform vibration modes and naturalfrequencies. Using Newmark gradually integral method research platform in the wholeunder the action of transient dynamic response, and the result of dynamic analysis of theamplification coefficient; Through the random vibration analysis, studied in random waveload, platform structure on the dynamic response of random load, according to the Steinbergproposed based on gaussian distribution and Miner linear cumulative damage law intervalmethod, carries on the fatigue strength calculation, check leg life.4. This paper expounds the structure optimization theory methods: zero order methodand first-order method. By defining variables chord center distance, chord wall thickness,horizontal bar pitch and horizontal bar wall thickness in size and shape optimization, getoptimal result, improve the platform structure，improve the design level.