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Homework Statement
I have to find the Shear Force and Bending Moment diagrams for this problem. The lengths in the picture are 1.2m each and the peak force is 4kN/m and I calculated the support reactions to be:
Ay=4,8kN (up)
Ma= 5.76kN.m (anticlockwise)
Homework Equations
These are what I'm looking for but failed to do...
The Attempt at a Solution
I first section the beam 0<x<4
Efy=0
+4.8 .5x*3.33xVx=0
I got the 3.33x by using similar triangles; if triangle 1 is (1,2;4) then sectioned triangle should be (x;y) so therefore 4/1.2=y/x x=3.33x
this gave me Vx=1.67x^3+4.8 which is wrong.
Then EMo=0
+Mx +.5x*3.33x*(x/3) 4.8x +5.76=0
which gets me Mx=0.56x^3 +4.8x +5.76
The correct answers for this question are:
Vx=4.8 (x^3/6)
Mx=4.8x (x^3/18) 5.76
I have a feeling I'm not using the triangle force correctly. Please advise.
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