Design And Optimization Of An Offshore Jacket Steel Structure

This paper presents a systematic design and research on the construction and testing of a jacket platform.this paper is designed to optimize the structural performance according to the special requirements proposed by the special environment;It's also designed to reduce the weight of the structure,improve the economic efficiency,optimize the design of the prefabricated layout process,reduce material waste,and provide a simple workflow and clear ideas for the material control and structural design of similar large-scale projects.This paper uses Tekla software to establish the steel structure model,and the SACS model is established according to the Tekla model.Firstly,the model is subjected to static analysis to check the stiffness and strength and find the optimal structural design solution.The total weight and center of gravity distribution of the structure are simulated by repeatedly applying the plumb node force during the self-weight analysis,and adjusted according to the UC value and deformation of the bars.In the static analysis,three different working conditions were simulated and tested separately to make the results more accurate,so the tests were conducted in different working conditions.ANSYS software was used to optimize the size and total weight of the structure,and the mathematical model of the objective function was established.And the distribution of each rod was more reasonable and the steel was saved.This paper analyzes the model under different wind loads,based on the owner's records and analysis of the local service environment.Different wind load conditions are designed separately,and the model is analyzed under different wind loads according to the surface wind pressure function of the structural rods and the wind load formula acting on the structure.In this case,the working conditions are divided into two cases:normal wind and storm,but because of the difference in the weight of the equipment in different areas of the modules on the structure,it is also necessary to distinguish the magnitude of the forces acting on the nodes in different areas.The results show that the deformation of the structure and the strength of the rods under both conditions can meet the requirements of the owner.In this paper,the strength of the steel pier and the crane card used in the construction of the module is verified,and the finite element software is used to simulate the two conditions of the crane card:lifting condition and forklift condition.The L-shaped plate of the main body of the crane card is designed and modeled with Shell181 units,and the maximum equivalent force is less than the rated stress,indicating that the crane card is safe and can withstand the overall weight;the steel pier is used to support the large model,and the load is applied after modeling,and the maximum equivalent force is less than the rated stress,indicating that the steel pier has sufficient strength and is safe.This paper summarizes the optimization of the modeling and nesting process and the site construction requirements to be noted during design based on feedback from the site.The nesting guidelines for plates and profiles are set up during the production and distribution of the nesting plates and adjusted according to the site machines so that the nesting drawings can be distributed to the construction process with less unnecessary material waste and easier to work with on site.