Strength of materials (shear and moment)

AI Thread Summary
The discussion centers on the calculation of shear and moment in a structural analysis problem. The initial calculations for reactions at points A and B are provided, but discrepancies arise in the moment values calculated from both sides of point x. It is pointed out that the shear diagram is incorrectly drawn, particularly in how concentrated loads are treated as distributed loads. The correct approach reveals jump discontinuities in shear values at critical points, specifically at points C and E. The user acknowledges the error and expresses gratitude for the clarification.
defdek
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R at B = 5.0625
R at A = 8.5kN-5.0625kN=3.4375kN

x/0.9375=(0.5-x)/4.5625

x=15/176

but moment near x there i get different from both side:
from A = 2.431kNm
from B = 2.346kNm

is there something wrong?
 

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Your shear curve is not drawn correctly. For example, starting at A, the reaction gives a shear of 3.4375 kN. The distributed load between A and C is 1 kN/m over a distance of
0.5 m. At C, there should be a jump discontinuity in the shear. Approaching from the left, the shear is 3.4375 - 0.5 * 1 = 2.9375 kN. The 2 kN concentrated load is applied at point C only. The shear value at C approaching from the right is 0.9375 kN. A similar situation will occur at point E with the 5 kN concentrated load there.

In other words, your shear diagram is incorrect because you have incorporated the concentrated loads as if they were distributed loads.
 
SteamKing said:
Your shear curve is not drawn correctly. For example, starting at A, the reaction gives a shear of 3.4375 kN. The distributed load between A and C is 1 kN/m over a distance of
0.5 m. At C, there should be a jump discontinuity in the shear. Approaching from the left, the shear is 3.4375 - 0.5 * 1 = 2.9375 kN. The 2 kN concentrated load is applied at point C only. The shear value at C approaching from the right is 0.9375 kN. A similar situation will occur at point E with the 5 kN concentrated load there.

In other words, your shear diagram is incorrect because you have incorporated the concentrated loads as if they were distributed loads.

Oh I didnt see that. Thank you so much... :D
 
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