文档介绍：摘要
摘 要
风能作为洁净的能量来源,受到各个国家的重视,随着时代的进步,风力发电技术得到越来越广泛的推广。塔架作为风力发电机主要的承重构件,在工程中发挥着重要作用。风力发电机塔筒承受着顶部桨叶和发电机舱轴压作用和水平风荷载作用,但已有研究表明,轴力对塔筒的影响很小,塔筒主要由受弯承载力控制。塔筒径厚比越大,截面越开展,抗弯承载力越高,但大径厚比易导致钢管局部屈曲,从而降低构件的承载力和延性。在塔筒内设置加劲肋,可避免局部屈曲对塔筒受力产生的不利影响。但从国内外已有的研究成果看,目前还未见有关大径厚比加劲塔筒的试验研究和理论分析。
论文主要针对大径厚比加劲钢管在弯矩作用下的力学性能进行试验研究和有限元分析。论文主要完成以下工作:
(1) 进行了 4 个加劲薄壁圆钢管和 6 个非加劲薄壁圆钢管的试验研究,试验中监测了构件的荷载、位移和应变的变化,研究了径厚比、加劲肋对构件刚度、承载力、延性和破坏模式的影响。
(2) 采用 ABAQUS 有限元软件建立了薄壁圆钢管和加劲圆钢管的有限元分析模型,模型中考虑了钢管初始几何缺陷和残余应力等因素对圆钢管受弯性能的影响,有限元分析结果和试验结果进行对比,验证并修正了有限元模型。
(3) 对薄壁加劲钢管受弯性能进行了参数分析,研究一字型加劲和槽型加劲对薄壁塔筒屈曲破坏模式、承载力、刚度及延性的影响;研究不同径厚比、加劲肋
形式、加劲肋数目、加劲肋尺寸和加载角度对钢管抗弯性能的影响。在大量参数
分析的基础上,提出了大径厚比加劲塔筒的设计建议,可为工程设计提供一定的参考。
关键词:大径厚比;圆钢管;加劲;抗弯;延性
哈尔滨工业大学工学硕士学位论文
Abstract
Wind turbines are ing an important alternative to standard energy provision. Wind energy is renewable and has no direct pollution related environmental effects, which makes it attractive in many countries. With the development of technique, wind energy technology develops rapidly. The main supporting structure of the wind turbine is assembled by thin-walled circular hollow section (CHS) steel tubes. For wind turbine tower, it is mainly subjected to horizontal wind load and vertical dead load caused by nacelle and rotor. It is found that the bearing capacity of wind turbine towers is controlled by bending moment. With the increase of diameter-to-thickness ratio, the load-carrying capacity increases evidently, but results in low ductility under bending moment. It is a good way to weld stiffener on CHS steel tubes to improve its stabiliy and ductiliy. At present, most of research is focused on the study of CHS steel tubes subjected to bending moment. And there is little research to study the behavior of CHS steel tubes with stiffeners. The main contents are as follows:
A total of 10 specimens is fabricated and tested, which includes 4 CHS steel tubes with stiffeners and 6 CHS steel tubes without stiffeners. All specimens are subjected to bending moment. The loa