結構相依逐步積分法之係數敏感度分析

先前研究的無條件穩定外顯式積分法同時具Newmark外顯式積分法計算上較為簡單與省時的優點與等平均加速度內隱式積分法沒有穩定條件的限制，因而可選用較大的積分時間步長進行逐步積分運算的優點。一般的逐步積分法積分方程式的係數皆為常數，然而，無條件穩定外顯式積分法其積分方程式的係數並非常數，是由結構的基本性質與積分時間步長的乘積表示的逐步積分法。因此對無條件穩定外顯式積分法而言，結構之基本性質中的初始勁度是非常重要的因素。一些高度非線性的材料，其結構受力後往往很快進入材料的非線性行為，因此在學術或在工程上對於結構的初始勁度量測往往因量測的標準不同而有所差異，如此一來，利用此量測初始勁度值所決定的積分方程式的係數將因量測的初始勁度值的不同而有所差異。對此，本論文將進一步經由數值分析與擬動態試驗,研究這種差異是否會影響無條件穩定外顯式積分法的準確性。研究結果得知，無論在數值分析或擬動態試驗上，使用無條件穩定外顯式積分法進行運算時，對於系統較重要的結構低頻反應並不會因量測的初始勁度值的不同而有明顯的影響。

關鍵字

逐步積分法；無條件穩定外顯式積分法；擬動態試驗

並列摘要

Formerly studied explicit integration method with unconditional stability, has explicit integration method to calculate simpler and a time-saving merit, and simultaneously holds implicit integration method unconditional stability the merit. Integration equations coefficient of this integration method is expresses by the structure basic nature and the integration time length of stride product. Speaking of uses explicit integration method with unconditional stability to carry on step-by-step integration Pseudodynamic test, carries on before the experiment essential to gauge the structure initial stiffness matrices in order to calculates integration equations coefficient, can use step-by-step integration method to carry on the operation. However, speaking of the highly non-linear material, when its initial stiffness often can gauge exerts the displacement different obtains different values, then, integration equations coefficient will have a difference because of initial stiffness values, then will have the influence to the explicit integration method with unconditional stability integral result.Therefore, the present paper will penetrate numerical examples and Pseudodynamic test, will discuss this kind of difference to explicit integration method with unconditional the stability precision influence. Knew by the result, reaction time structure in important low frequency, the precision of integral won’t have the obvious influence because of difference of the initial stiffness gauging.

並列關鍵字

step-by-step integration method ； explicit integration method with unconditional stability ； Pseudodynamic test

參考文獻

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[6] Chang S.Y.,”Integrated Equations of Motion for Direct Integration Methods,, ”,

國際替代計量

結構相依逐步積分法之係數敏感度分析

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