Ansys 中beam4實常數中Ixx—扭轉慣性矩是什麽，是極慣性矩嗎？

the torsional moment of inertia (IXX), and the material properties. For stiffness purposes, the torsional moment of inertia, if IXX is equal to 0.0 or not specified, is assumed to be equal to the polar moment of inertia (IYY + IZZ). For inertial purposes, the torsional (rotational) moment of inertia used is the polar moment of inertia, and is therefore not affected by the value entered for IXX. The IXX value should be positive and is usually less than the polar moment of inertia.

以剛度為目的，IXX是扭轉慣性矩，如果IXX＝0或不指定，系統會假設IXX=IYY+IZZ（極慣性矩）；以慣性為目的，扭轉慣性矩使用的就是極慣性矩，並且不會受輸入的IXX值的影響（即不管輸入的IXX為多少，在這種情況下，IXX都等於極慣性矩。IXX值應該為正且總是小於極慣性矩。

只是做了大致的翻譯，如果懂英語請看英文原版。