(2015更新版)材料力学网上作业题参考答案20151014 - 图文 下载本文

EIv????积分得:

Mex?Me 3aMex2EIv????Mex?C1 (3)

3a2Mex3x2EIv???Me?C2x?D2 (4)

3a62x?3a时,vB?0;代入(4)式,得 3Mea39a2??Me?C23a?D2?0

22x?3a时,vC1?vC2;?C1??C2

联立解得系数C1,C2,D2

x?0时,?A?Mea 6EIMea x?3a时,?B??3EI7.解:?C1??B1Fa2??2EI,vC1Fa3, ??3EIFa3Fa25Fa3得vB?? ??a??13EI2EI6EI?B24Fa22Fa28Fa3,vB?? ????23EI2EIEIFa22Fa25Fa2?????

2EIEI2EI

叠加原理得:

?B??B1??B2vB?vB1?vB28. 解:?A18Fa35Fa37Fa3?????

3EI6EI2EIql3ql4ql3?,vA??,?C??A?126EI8EI8EI49

ql4,vC??24EI,

vA2ql4ql3l5ql4, ??????24EI8EI248EIql3ql37ql3???6EI8EI24EI叠加原理得:

?A??A1??A2vA?vA?vA

ql45ql411ql4?????

128EI48EI

9. 解:v?Fl3Fl2C1?48EI?Fl2,B1?16EI vC2?Fl316EI,?B2??3EI ????13Fl2B?B1??B248EI vFl2C?vC1?vC2? 24EI 10.

?7Fa2C1?6EI3??q(2a)qa3C2?A??24EI??3EI

v??qa3qa4C2A?a?3EI?a?3EI叠加原理得:

???5qa3C?C1??C26EI 2qa4vC?vC1?vC2??3EI

ql2?l11. 解:?A??Melql313EI??6EI,vC21??2l2ql46lEI(l2?4)??32EI

50

48EI叠加原理得:

vqa4C1??EI