考虑内压影响的薄壁钢板筒仓屈曲承载力研究  

Buckling Strength of Thin Walled Steel Silos with Internal Pressure

作　　者：王培军[1] 郑玉超[1] 

机构地区：[1]山东大学土建与水利学院,济南250061

出　　处：《特种结构》2013年第6期7-14,共8页Special Structures

基　　金：国家自然科学基金项目;编号51008181

摘　　要：一定程度的内压会降低薄壁钢板筒仓对缺陷的敏感性,提高其弹性屈曲承载力;但内压过高时,筒仓会出现弹塑性强度破坏或弹塑性屈曲破坏,其承载力反而降低。我国现有《粮食钢板筒仓设计规范》(GB50322-2011)给出了考虑内压影响的屈曲承载力计算公式,但该公式只适用于计算内压较低时筒仓的弹性屈曲应力,对高内压下筒仓弹塑性破坏时采用该公式将得到不安全的结果。采用有限元方法对轴压和水平内压作用下有初始缺陷的筒仓进行了参数分析,分别讨论了内压大小、材料强度和径厚比等对筒仓屈曲应力的影响,提出了筒仓在轴压和均匀内压作用下的弹性屈曲应力和弹塑性屈曲应力计算公式,并对《粮食钢板筒仓设计规范》公式进行了修正。经验证,该计算公式与有限元分析结果基本吻合。The existence of internal pressure can reduce the sensibility of buckling stress of a steel silo to the geometric imperfection,and can improve its buckling bearing capacity.However,elastic-plastic failure may occur when the silo is under high internal pressure.In Code for Design of Grain Steel Silos（GB50322-2011）,a design equation is present to calculate the buckling stress of a steel silo with internal pressure.However,the method is applicable only when the silo is under a low level of internal pressure buckling elastically.It will produce un-safety results if it is used to predicate the buckling strength of the silo under higher internal pressure.A systematic parametric study was carried out to investigate the elastic and elastic-plastic buckling behaviors of the imperfect steel silo with internal pressure.Studied parameters include the level of internal pressure,the steel strength and the radius to thickness ratio.Design equations were proposed for calculating both the elastic and elastic-plastic buckling stress of steel silos under the combined axial compression and internal pressure.And the buckling stress predicated by the proposed equations agrees well with that obtained by the finite element model.

关 键 词：薄壁筒体 筒仓 弹性屈曲 弹塑性屈曲 内压 

分 类 号：TU392.1[建筑科学—结构工程]