工程力学试卷A答案 - 百度文库 ر

C±ԵӦʱȻMC?MAy1?y2Ҫ󣬲˶ӦĴ

У¸Ӧ A±Ե

MAy1(4.8?103Nm)?(80?10?3m)?c???72?106Pa?72MPa???c??150MPa ?64IZ5.33?10mAϱԵ

MAy2(4.8?103Nm)?(40?10?3m)6?t???36?10Pa?36MPa???t??60MPa ?64IZ5.33?10mC±Ե

MCy1(3.6?103Nm)?(80?10?3m)?t???54?106Pa?54MPa???t??60MPa ?64IZ5.33?10mǿ

塢ͼʾеĵԪӦӦǵ淽λڵԪͼϡ

ͼʾԪϵӦΪ

?x??20MPa,?y?30MPa,?xy?20MPa Ӧ

2??20?30??max??x??y??x??y??37MPa?20?30?2?2?????????20MPa?????xy??????min??2222????27MPa??2??

ӦΪ ?1?37MPa,?2?0,?3??27MPa ȷƽλ

tan2?0??2??20?2?x???0.8

?x??y?20?30ȡֵa0=-19.3㣬ʾͼʾĵԪϡ

Ӧ

5 ҳ 6 ҳ

?max?

?1??32?37?(?27)MPa?32MPa 2 6 ҳ 6 ҳ