???????????????
4??1500??8000 21??
10??2000??8000 70??
4??1500??800035??
4??1500??8000 80??
8??1800??8000 70??
6??1800??8000 80??
???????????????
?????????????????????????
1?????????????1.95??105MPa???????????????????????????????
??1.96 19.3 19.1??/3=1.93??105MPa??
2?????????????????μ???????????????
??L=P*L*(1-e-(kx ???))/(kL ???)/Ay/Eg
????????????????
??????????????????????????????????????????????????????????????????????????????????????????????г?????????????Ρ??磬?????????????????????????????????????????????λ??????ò??????д?????б????????淶?????????????????????????????г?????ɡ????????????????????????????????????????Ч????????????
????4??28????й?????2??q690qe?????????????С??????
