ΣMA =0,FB.a -F.a/2 -m =0
FB = F/2 +m/a （向上）
ΣFy =0.FAy +FB -F =0
FAy +(F/2 +m/a) -F =0
FAy =F/2 -m/a (若F/2>m/a,则FAy向上）
ΣFx =0,FAx =0
直角折杆AB结构尺寸及荷载如图所示,求A、B支座的支座反力.
ΣMA =0,FB.a -F.a/2 -m =0
FB = F/2 +m/a （向上）
ΣFy =0.FAy +FB -F =0
FAy +(F/2 +m/a) -F =0
FAy =F/2 -m/a (若F/2>m/a,则FAy向上）
ΣFx =0,FAx =0