=0.12×12×12.4×1010/36002
=13778源`自*优尔?文.论/文`网[www.youerw.com
③、A-5(1根)
K=4.5/7.233=0.62
αc=(0.5+K)/(2+K)=0.428
Di3=αc×12×ic/h2
=0.43×12×7.233×1010/83002
=5392
④、A-4、A-6(2根)
K=(4.5+3.8)/(12.42)=0.32
αc=K/(2+K)=0.14
Di4=αc×12×ic/h2
=0.4×12×12.4×1010/36002
=15730
⑤、B-1、C-1、B-9、C-9(4根)
K=(2.5+3.38)×2/(12.4×2)=0.474
αc=K/(2+K)=0.19
Di5=αc×12×ic/h2