刚架结构极限承载力分析的广义塑性铰研究  

Generalized plastic hinge for ultimate bearing capacity of rigid-framed structures

作　　者：杨绿峰[1,2] 柏大炼 杨大尉[2,3] Yang Lufeng;Bai Dalian;Yang Dawei(School of Civil Engineering&Architecture,Guangxi University,Nanning 530004,China;Key Laboratory of Disaster Prevention and Structural Safety of the Ministry of Education,Guangxi University,Nanning 530004,China;Anhui Transport Consulting and Design Institute Co.,Ltd.,Hefei 230088,China)

机构地区：[1]广西大学土木建筑工程学院,广西南宁530004 [2]广西大学工程防灾与结构安全教育部重点实验室,广西南宁530004 [3]安徽省交通规划设计研究总院股份有限公司,安徽合肥230088

出　　处：《土木工程学报》2020年第4期31-37,共7页China Civil Engineering Journal

基　　金：国家自然科学基金重点项目(51738004);面上项目(51478125)。

摘　　要：传统塑性铰法及其改进方法具备比例特点,能够根据外荷载与内力之间的比例关系快捷确定刚架的塑性铰位置和极限承载力,但不能应用于多内力组合作用下的刚架极限承载力问题。随后发展起来的二阶塑性铰法和精细塑性铰法尽管解决了该问题,但不具备比例特点,需通过大量迭代试算、并连续调整荷载增量来确定刚架的塑性铰位置和极限承载力,导致理论复杂,计算效率低。为此,文章利用广义屈服准则提出内力组合因子的定义,据此建立具备比例特点的广义塑性铰法,能够快捷处理刚架结构在多内力组合作用下的极限承载力问题。首先,利用广义屈服准则研究建立内力组合因子,据此修正刚架单元在不同加载步的截面强度。然后,利用齐次广义屈服函数和标准化内力定义单元承载比,并根据荷载与单元承载比之间的比例关系快捷确定各加载步的塑性铰位置和极限承载力。最后,通过与弹塑性增量法和改进塑性铰法对比分析,验证了该方法具有简捷、高效和高精度特性。The traditional plastic hinge method(PHM) and its improved methods(iPHM) have proportional property,which can be used to determine rapidly the position of plastic hinge and ultimate bearing capacity of rigid-framed structures.However,these methods cannot be applied to rigid-framed structures under multiple internal forces.The second-order plastic hinge method(SPHM) and the refined plastic hinge method(RPHM) subsequently developed can solve this problem,but they don’t have the proportional property,and instead they require a large number of iterative trials to determine the position of hinge position and ultimate bearing capacity.Hence,the two methods are inevitably complex and inefficient.In this work,a generalized plastic hinge method(GPHM) with proportional property was developed on the basis of the generalized yield criterion and the combining factor of internal forces to figure out the difficulties.Firstly,the combing factor of internal forces was presented to modify the element sectional strength at each loading step.Secondly,the element bearing ratio is defined by homogeneous generalized yield function and standardized internal force,then the plastic hinge position and ultimate bearing capacity of frame can be determined by the proportional property.Finally,comparison of GPHM with EPIA and iPHM was performed to demonstrate the high accuracy and efficiency of the proposed GPHM.

关 键 词：广义塑性铰 内力组合因子 齐次广义屈服函数 极限承载力 刚架结构 

分 类 号：TU311.4[建筑科学—结构工程]