结构力学试题2(9)

0?2i?? i/3??l5lm?2A?2kAl?1.5m?2A?2l?0.75m?2A??0

22?2?2k/1.625m?1.23k/m??1.109k/m?11??22

二十二．

4l3l3?;?12??21?? 3EIEI?11m1?2X1??12m2?2X2?X1 ?21m1?2X1??22m2?2X2?X2

设 ??1

?11m1?2(1??)X1??12X2?0?11?21X1?(1??)X2?0?11

1???3/4?0 ?1?7/4;?2?1/4

?3/41???12?3EIEI323 ;??0.655EI/ml;??3;??1.732EI/ml122337mlmlX11X??1;12?1; X21X22二十三．

1314.5?106???8426.28;

156?1032??2??600?62.8; 60??1.88

A?0.0224?10?3?1.88?0.0224?10?3 m

N?55.33 kN