摘要
直筒-锥段型钢结构冷却塔自重较轻、塔型相对规则,正逐步成为火电行业大型冷却塔建设的新方向,而该结构大跨度大空间特点导致的强震下响应与风致整体稳定性,是钢塔结构设计的挑战。使用有限元软件SAP2000建立钢冷却塔模型,进行恒荷载、风载和地震作用下的计算,分析塔筒的受力情况和内力分布规律;以一阶线性屈曲模态作为钢塔初始缺陷状态,以H/300(H为塔高)作为初始缺陷大小,基于双重非线性分析,探究此类钢结构冷却塔真实工况下的风致非线性屈曲规律。结果表明:在多向地震作用下,钢冷却塔的位移符合《空间网格结构技术规程》(JGJ 7—2010)要求,锥段和直筒段主要分别发生弯曲变形和剪切变形,整个塔体的变形性能满足我国抗震设防要求;考虑双重非线性下钢结构冷却塔临界屈曲承载力下降,直筒段设置的加强环有力保证了结构刚度。为类似大跨度钢塔抗震性能及稳定性能评估提供一定参考。
ABSTRACT:The steel cooling towers with cylinder-cone section,due to its light self-weight and regular tower shape,is gradually becoming a new trend in the construction of large-scale cooling towers in the thermal power industry.However,the large span and large space characteristics of this structure result in strong earthquake re-sponse and overall wind-induced stability,which are challenges in the design of steel tower structures.This pa-per uses the finite element software SAP2000 to establish a steel cooling tower model,performs calculations un-der constant load,wind load and earthquake action,and analyzes the stress distribution condition of the tower.The first-order linear buckling mode is taken as the initial defect state,and H/300(H is the tower height)is taken as the initial defect size.Based on the dual nonlinear analysis,the wind-induced nonlinear buckling law of this type of steel cooling tower structure under real working conditions is explored.The results show that un-der multi-directional earthquake,the displacement of the steel cooling tower meets the requirements of JGJ 7—2010 Technical Specifications for Spatial Grid Structures.The cone and the straight tube section mainly undergo bending deformation and shear deformation respectively,and the deformation performance of the entire tower body meets the seismic fortification requirements of China.Considering the double nonlinearity,the critical buckling bearing capacity of the cooling tower is reduced,and the reinforcement ring set in the straight section effectively ensures the structural rigidity.This study provides references for evaluating the seismic performance and stability of similar large-span steel towers.
作者
周钰
杨建林
Zhou Yu;Yang Jianlin(Jiangsu Urban and Rural Construction Vocational College,Changzhou 213000,China)
出处
《特种结构》
2024年第1期12-17,共6页
Special Structures
基金
江苏省高等职业院校高水平专业群建设项目(ZJQT21002401)。
关键词
钢结构冷却塔
双非线性
屈曲分析
风致稳定性
Steel cooling tower
Double nonlinearity
Buckling analysis
Wind-induced Stability
