解:应用截面法,由平衡方程求得: F=-F-G1(0)=-F-pg4y=-60-2.46ykN 此为直线方程,F(0)=-60kN,F3(3.5)=-68.6kN, 得轴力图。 F FNkN 60 643 F㾷˖ ᑨ⫼៾䴶⊩ˈ⬅ᑇ㸵ᮍ⿟∖ᕫ˖ 㾷˖ ᑨ⫼៾䴶⊩ˈ⬅ᑇ㸵ᮍ⿟∖ᕫ˖  = − −
() = − − ρ ⋅  ⋅ ⋅ = − −    ( ) ᕫ䕈࡯ ೒DŽ ℸЎⳈ㒓ᮍ⿟         = −  = −