- #1

- 23

- 3

- Summary:
- Moment equilibrium

I have a quesrion about forming the eqaution of moment equilibrium.

As shown in the picture at cut 1 there are 2 vertical forces and a bending moment. I expect V=A.

If I apply moment equilibrium about the point where the bending moment is, we get that Ay*x = M(1). But how about if I take moment about point A, is this equation of moment equilibrium valid: (V*x) -M = 0(2). Until now every exercise solved I was applying moment equiibirum about the point where the bending moment is.

Now I am doing buckling and I saw an example with fixed end column. The method of section was used again and at the one end (A) there was a horizontal force(P) with fixed-end moment(Q) and on the other end (B, the sectioned end) there was an equal and opposite horizontal force (P) and bending moment M(x). The vertical distance between the two ends was v(x) and the equation for moment equilibrium was P*v(x) = M(x) + Q and I got confused about which point the moment were takend ( A or B).

As shown in the picture at cut 1 there are 2 vertical forces and a bending moment. I expect V=A.

If I apply moment equilibrium about the point where the bending moment is, we get that Ay*x = M(1). But how about if I take moment about point A, is this equation of moment equilibrium valid: (V*x) -M = 0(2). Until now every exercise solved I was applying moment equiibirum about the point where the bending moment is.

Now I am doing buckling and I saw an example with fixed end column. The method of section was used again and at the one end (A) there was a horizontal force(P) with fixed-end moment(Q) and on the other end (B, the sectioned end) there was an equal and opposite horizontal force (P) and bending moment M(x). The vertical distance between the two ends was v(x) and the equation for moment equilibrium was P*v(x) = M(x) + Q and I got confused about which point the moment were takend ( A or B).