摘要
为研究几何非线性条件下分阶段成形结构平衡状态与无应力状态量的关系,定义了梁单元无应力构形及无应力状态量的概念。构建2个结构系统状态和3个单元状态,基于单元无应力状态,考虑结构几何非线性效应,利用最小势能原理建立基于平面梁单元分阶段成形结构线形控制方程,该方程从理论上证明了无应力状态法原理三(分阶段成形结构通过主动控制构件单元的无应力状态量,可以实现相互独立的结构内力和结构线形)在几何非线性结构中的适用性。当计算状态取平衡状态时,线形控制方程为几何线性方程,提出了单元无应力状态量的间接法求解。通过某三跨连续箱梁结构算例验证了间接法的可靠性,同时进一步验证了无应力状态法原理三在几何非线性结构中成立。
In this paper,the relationship between the equilibrium state variable and stress-free state variable of the structure that takes form in a phased manner is studied using geometric nonlinear analysis and the concepts of the stress-free geometric shape and stress-free state variable of a beam element are defined.Two structural system states and three element states are formulated,based on the element stress-free state,a geometric shape governing equation to calculate the geometry of the structure constructed in stages is developed following the minimum potential energy principle and considering the geometric nonlinearity effect of structure.The equation theoretically proves the feasibility of the principle 3 of the stress-free state method,namely for the structure that takes form in a phased manner,the stress-free state variable of an element can be actively controlled to achieve the independent internal force and geometry of the structure.When the equilibrium state is drawn for calculation,the geometric shape governing equation degenerates to a geometric linear equation,based on which the indirect solution to obtain the stress-free state variable is proposed.The reliability of the indirect method is verified by the calculation of a real three-span continuous box girder structure,and the validity of the principle 3 of the stress-free state method in the structure with geometric nonlinear effect is also proved.
作者
苑仁安
秦顺全
喻济昇
YUAN Ren-an;QIN Shun-quan;YU Ji-sheng(China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.,Wuhan 430056,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2022年第4期46-52,共7页
Bridge Construction
基金
中国中铁股份有限公司科技研究开发计划项目(2021-专项-01)。
关键词
桥梁工程
平面梁单元
几何非线性
无应力状态量
无应力构形
线形控制方程
间接法
bridge engineering
plane beam element
geometric nonlinearity
stress-free state variable
stress-free geometric shape
geometric shape governing equation
indirect method
