Analysis On Load Capacity And Optimization Of Fabricated Steel-concrete Hybrid Tower

Tower is the main supporting structure of the wind turbine.The mechanical characteristics of the tower have a direct impact on the working performance of the wind turbine.In order to improve the bearing capacity of the tower,the thickness and diameter of the bottom are usually increased in the designing of the traditional steel cylinder tower.This can cause difficulties in processing the steel cylinder and the problem of transportation height limit.Combined with the advantages of steel and concrete,the prefabricated steel-concrete hybrid tower solves the above problems to a certain extent.Therefore,it is widely concerned by the wind power industry.In this paper,the bearing capacity of the hybrid tower was analyzed based on ABAQUS finite element software.And the optimized design of the hybrid tower was carried out by combining ISIGHT software.1.A 2MW wind turbine hybrid tower is taken as the model for analysis.Unbonded prestressed tendons and flange are used for assembly and connection between concrete and steel.The mechanical properties of the tower are studied under three working conditions: normal power generation,cut-out wind speed and extreme shutdown.The tower load under three working conditions is calculated and the bearing capacity of steel tower section and prestressed concrete tower section is checked respectively.2.Based on ABAQUS,the natural vibration frequency and mode of the tower are analyzed,and the static response,stability and ultimate bearing capacity of the tower under three working conditions are studied.The ‘Riks' method was used to analyze the failure process of the tower,and the minimum values of steel buckling load factor,concrete tension load factor and compression load factor were taken as the ultimate load factor of the tower.So as to determine the failure control factors and failure modes of the tower.3.The influence of the height of concrete tower section,the size of prestress and the wall thickness of steel tower section on the bearing capacity of the tower is analyzed.The results show that increasing the height of concrete section,the size of prestress and the wall thickness of steel tower section within limits can improve the bearing capacity of the tower and change the failure mode of the tower.4.Python language was used for parametric modeling,and ISIGHT software was combined to optimize the hybrid tower using multi-island genetic algorithm.The cost of the tower was taken as the target,and the strength,stiffness,stability and natural vibration frequency of the tower were taken as constraints.Compared with the original tower,the cost of the optimized tower is reduced by 11.6%,and the bearing capacity of the tower is reduced by 7.6%.The failure mode of the tower is changed from steel buckling to concrete tensile failure.