1、計算機輔助工程分析計算機輔助工程分析內容內容2 有限元法的直接剛度法有限元法的直接剛度法 2.1 直梁的有限元分析直梁的有限元分析要求要求 了解：了解：單元、節點單元、節點的概念的概念 理解：梁單元理解：梁單元節點內力、節點載荷節點內力、節點載荷的概念的概念 梁梁單元剛度矩陣單元剛度矩陣的概念的概念 掌握：梁單元剛度矩陣的建立辦法掌握：梁單元剛度矩陣的建立辦法 利用利用節點平衡節點平衡組裝整體剛度組裝整體剛度作業作業 超靜定懸臂梁的有限元分析超靜定懸臂梁的有限元分析上節回顧上節回顧整體離散單元組裝上節回顧上節回顧本節提要一個例題：MDCBAZ212343ZM4321ZM4321M4321ijq

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5、lllmM4321Z1M1m11q11Z4M4m43q43Z2M2m22q22q21m21Z3M3m33q33q32m32Z1M1m11q1100YM111112231221111223212612626462EIZqflfllEIMmlfllfll00YM1222211223223331222222112232222333212612621261262626426462EIZqqflfllEIflfllEIMmmlfllfllEIlfllfllZ2M2m22q22q21m21Z4M4m43q43Z3M3m33q33q32m32 11223344,TQZ M ZMZ MZM QK Q 1122

6、3344,Tffff K 222222322222212612600006462000012612 126 612600626 6 44620020012612 66 36300626 3 42300006363000033 2llllllllllllllllllEIKlllllllllllllllllll 對稱，稀疏，奇異，主對角元恒正 QK122122222233222234412612600006462000012612 12661260062664462002000126126636300062634230000636300000ZllMllllZZllllMMllllllllEIZl

7、llllMllllllllZllM1122334224000332ffffllll122122222233222234412612600006462000012612 12661260062664462002000126126636300062634230000636300000ZllMllllZZllllMMllllllllEIZlllllMllllllllZllM1122334224000332ffffllll22223322232242401260086202012618330623600032fZlmlllEIfllllllllllll 對稱，稀疏，非奇異，主對角元恒正 22223322232242401260086202012618330623600032fZlmlllEIfllllllllllll 11223344,Tffff本節課小結第一步，對直梁進行離散化，劃分為有限個單元。第二步，對各結點和單元進行編碼。第三步，