[轉(zhuǎn)載][ABAQUS問(wèn)題一] import from Standard to e

在SIMWE論壇上經(jīng)常有人問(wèn)到*import的相關(guān)內(nèi)容,Robert_Su對(duì)此也做了詳細(xì)的說(shuō)明,具體可登錄http://forum.simwe.com論壇上參看。

上述內(nèi)容也提到standard模塊中有重力作用下,import到explicit模塊時(shí)需要繼續(xù)施加重力作用。ABAQUS Analysis幫助中第9.2.2頁(yè)的load部分也提到:Loads, including those applied for connector actuation, defined in the original analysis are not imported. Loads may, therefore, need to be redefined in the import analysis. There are no restrictions on the loads that can be applied when results are imported from one analysis to the other. In cases when the loads need to be maintained at the same values as in the original analysis, you can prescribe a constant (step function) amplitude variation for the analysis step (see“Prescribing nondefault amplitude variations” in “Procedures: overview,” Section 6.1.1) to apply the loads instantaneously at the start of the step and hold them for the duration of the step. Alternatively, you can refer to an amplitude curve in the load definition (see“Amplitude curves,” Section 30.1.2).

但對(duì)重力作用下是否會(huì)出現(xiàn)震蕩,及震蕩后該如何調(diào)整,沒(méi)有一個(gè)明確的說(shuō)法。這里自己做了兩個(gè)算例,僅說(shuō)明重力是會(huì)出現(xiàn)震蕩,至于如何控制,還有待進(jìn)一步的嘗試。

(1)一個(gè)實(shí)體塊的自重作用下(材料均為彈性)

說(shuō)明:簡(jiǎn)單的實(shí)體從standard輸入到explicit狀態(tài),僅模擬重力狀態(tài);
圖1左邊為隱式計(jì)算后得到的豎向變形;右邊為顯式最初狀態(tài)(import),云圖兩者一致;
圖2左邊為顯式最初狀態(tài)(import);右邊為顯式1s后的豎向變形,云圖兩者一致;

圖1 隱式的導(dǎo)入狀態(tài)(左邊),右邊為顯式的最初狀態(tài)

圖2 顯式模塊下重力加到1s時(shí)的狀態(tài)

說(shuō)明:模擬簡(jiǎn)單的框架-核心筒從standard輸入到explicit狀態(tài),僅模擬重力狀態(tài);
圖3左邊為隱式計(jì)算后得到的豎向變形;右邊為顯式最初狀態(tài)(import),云圖兩者一致;
圖4左邊為顯式最初狀態(tài)(import);右邊為顯式1s后的豎向變形,云圖相差很大;

圖5表示頂點(diǎn)豎向位移的震蕩圖

圖3 隱式的導(dǎo)入狀態(tài)(左邊),右邊為顯式的最初狀態(tài)

圖4 顯式模塊下重力加到1s時(shí)的狀態(tài)

圖5 頂點(diǎn)豎向位移的震蕩現(xiàn)象

小結(jié):

(1) 實(shí)體單元未出現(xiàn)震蕩;

(2)梁柱和殼出現(xiàn)震蕩

原因猜測(cè)中。。