Abstract: In this paper, by using Noutong's and Bailei's experimental formulas and elastic anslogy method, the total complement energe function of bar system structures is obtained. Meanwhile when Lagrangians are intruduced the conditional minimax problems of the complement energe function may be changed into unconditional minimax problems of Lagrange function, and by means of which the creeped stress of indeterminate bar system structures is computed. Examples are also given to describe its applications. With clear concepts and convenient calculation, the paper has practical value.

Key words: bar system structure, creeping, elastic analogy, complement energe function, Lagrange function, minimax value

摘要： 本文应用诺通与拜勒的经验公式,采用"弹性比拟"的方法,获得杆系结构的总余能函数。与此同时,引入拉格郎日乘子,将求总余能函数的条件极值问题,转化为求拉格朗日函数的无条件极值问题,并用以计算超静定杆系结构的蠕变应力。文中用实例说明了应用,概念清晰,计算简便,具有一定的实用价值。

关键词: 杆系结构, 蠕变, 弹性比拟, 余能函数, 拉格朗日函数, 极值