Singularity Functions for Beam Bending

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A beam with vertical reaction loads at both ends experiences a distributed load of 2,000 N/m from 0cm to 5cm and a point load of 1,000 N at 7.5cm. The calculated reaction loads are 325 N at the left end and 775 N at the right end. The singularity function for shear is correctly defined, but when transitioning to the moment function by increasing the exponents, the output does not align with expectations. A suggestion is made to check for typographical errors in the moment equation, particularly in the integration terms. This adjustment may resolve the discrepancies observed in the moment function's behavior.
tangodirt
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There is a beam of width 10cm, and vertical reaction loads on each end (x1 = 0cm, x2 = 10cm). Starting from the left end of the beam, we have a vertical distributed load of 2,000 N/m spanning from 0cm to 5cm. Finally, we have a 1,000 N point load located 7.5cm from the left end of the beam.

Through statics, it can be said that the left most reaction load (x1 = 0cm) is of magnitude 325 N while the right most reaction load (x2 = 10cm) has a magnitude of 775 N.

My singularity function for this system is shown below:

V = 325<x - 0>^{0} - 2000<x - 0>^{1} + 2000<x - 0.05>^{1} - 1000<x - 0.075>^{0} + 775<x - 0.1>^{0}

Which, when plotted (my end goal here), works perfectly and as it should. My issue comes when I switch the shear (V) singularity function to a moment function by increasing the exponents by one (as I've been told).

Through integration of the shear singularity function, the moment equation then becomes:

M = 325<x - 0>^{1} - 2000<x - 0>^{2} + 2000<x - 0.05>^{2} - 1000<x - 0.075>^{1} + 775<x - 0.1>^{1}

Which doesn't work quite as well. The moment function falls completely apart, but from every source I've read so far, it shouldn't. Also, if I draw the moment equation by hand (through the "area under the curve" approach), it hardly matches the output of the moment singularity equation.

Any ideas?
 
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tangodirt: But for n ≥ 0, w*integral[(<x - a>^n)*dx] = w*[1/(n+1)]*<x - a>^(n+1), not w*<x - a>^(n+1). Therefore, don't the second and third terms of your M equation contain a typographic mistake? See if this resolves the problem.
 

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