摘要
针对由索组成的荷载缓和体系的非线性分析,提出了一种虚拟应变计算法。该方法在保持索单元初内力一定的前提下,通过调整单元的弹性模量E或截面积A将初应变0ε设为较大值。把荷载分成多个足够小的荷载步分步加载,在计算完每一荷载步后,将单元应变重新赋为0ε并修正结构几何模型,作为下一荷载步计算的初始模型。算例表明:虚拟应变法在计算过程中能够基本保证结构单元内力恒定,是一种能够模拟由索组成的荷载缓和体系运行的有效方法;同时初始应变0ε越接近于1计算结果越精确。
To ensure the invariableness of initial forces of cable elements in the load-relieving system composed of cables, a dummy-strain method was proposed in this paper. In this method, initial strain ε0 was assigned a relatively large value by adjusting the value of the elastic module E or the cross-section area A under the condition that the initial forces of cable elements were constant. Meanwhile, the loads were divided into many small increments and applied step by step. After the calculating of each increment, the geometrical model of the structure was revised and the initial strain ε0 was assigned to corresponding elements again. The examples were shown that the initial forces in cable elements were invariable nearly and the dummy-strain method was an effective method, The initial strain ε0 was nearer to 1.0, and the result was more accurate,
出处
《科技通报》
2007年第3期392-395,共4页
Bulletin of Science and Technology
基金
国家自然科学基金资助项目(50478079)
关键词
荷载缓和体系
虚拟应变法
索单元
内力恒定
load-relieving system
virtual-strain method
cable elements
initial constant force
