Abstract: In?the?process?of?establishing?model?of?cable-stayed?bridge?by?use?of?ANSYS,?it?is?necessary?to?input?the?initial?cable?force?precisely.?But?there?is?no?simple?method?provided?by?ANSYS?to?obtain?the?initial?internal?force?directly,?so?other?alternative?methods?should?be?used,?such?as?element?birth?and?death,?the?initial?strain?method?and?the?temperature?load?method.?After?discussing?the?problems?of?single?simulation?method?and?cyclic?iteration?method,?a?new?method?based?on?matrix?analysis?is?proposed.?This?method?considers?the?mutual?influence?of?cable?force,?modifies?the?cyclic?iteration?formula,?and?simulates?precisely?the?cable?forces?of?cable-stayed?bridges.?At?the?same?time,?the?conventional?cyclic?iteration?method?is?proved?as?special?cases?of?matrix?analysis?method.?The?feasibility?is?verified?by?cable?force?simulation?of?Sutong?cable-stayed?bridge.?The?method?also?provides?thought?to?further?develop?ANSYS?and?solve?similar?problems.

Key words: element birth and death ;initial strain , temperature load , cyclic iteration , matrix analysis ;

摘要： 用ANSYS对斜拉桥进行建模时,需要输入初始索力,但ANSYS并没有直接提供施加初内力的方法,只能利用 单元的生死特性、单元初应变或者温度荷载来模拟斜拉索索力。讨论了单次模拟法和循环迭代法存在的问题,提 出了一种基于矩阵分析的方法;考虑斜拉索索力之间的相互影响,修改了循环迭代公式,能实现索力的精确模拟, 并证明常规的循环迭代法只是矩阵分析法的特例。通过苏通大桥斜拉桥索力的精确模拟,验证了该方法的可行 性,为以后类似问题的ANSYS二次开发提供了思路。

关键词: 单元生死, 初应变, 温度荷载, 循环迭代, 矩阵分析