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Hi guys. I have come across an obstacle that I have not managed to find a satisfactory solution to. I am sure the problem is easy for the experts here, but the solution completely eludes me. I want to make a function to plot bending moments caused by an eccentric load. My aim is to make an equation/function that can plot a continuous bending moment diagram, while being able to scale how many loads is acting on the member. Thank you for your time. Best regards, Hans Kristian. test.sm (107kb) downloaded 13 time(s).
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Do you mean a function that will represent M(x)... up to 100 ? Certainly from selecting representative support points ! test (3).sm (109kb) downloaded 12 time(s).
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Originally Posted by: Jean Giraud Do you mean a function that will represent M(x)... up to 100 ? Certainly from selecting representative support points ! test (3).sm (109kb) downloaded 12 time(s). Hi Jean, I want a function that will represent M(x) where the eccentric load P will be divided into n equal loads which are spaced out evenly along the length of the member. Does that make sense?
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saw.sm (8kb) downloaded 10 time(s). |
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Originally Posted by: hanskl Hi Jean,
I want a function that will represent M(x) where the eccentric load P will be divided into n equal loads which are spaced out evenly along the length of the member. I guess it makes sense, that stuff is not my cup of tea. You mean the 100 lines is typical of eccentric load model but each one will be of different parameters [your conditions] ??? Big project in view Captain ! We have a utility that divides a range in N equal spaces> That will make some lines longer/shorter as per the how those loads appear on the beam. Do you have some material from else source ?
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Now with proper scaling saw1.sm (6kb) downloaded 18 time(s). |
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Originally Posted by: Jean Giraud Originally Posted by: hanskl Hi Jean,
I want a function that will represent M(x) where the eccentric load P will be divided into n equal loads which are spaced out evenly along the length of the member. I guess it makes sense, that stuff is not my cup of tea. You mean the 100 lines is typical of eccentric load model but each one will be of different parameters [your conditions] ??? Big project in view Captain ! We have a utility that divides a range in N equal spaces> That will make some lines longer/shorter as per the how those loads appear on the beam. Do you have some material from else source ? The application for this sheet is going to be on sandwich concrete wall panels where the weight of the exterior non-bearing layer of concrete acts on the interior bearing layer. The actions to consider are N and M. In practical application, N will be split into 2-4 equal loads, but I wanted to make a framework that could split the load into n parts, just for fun..
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Thank you Martin, this is exactly what I am looking for! Although your expression is both much simpler and much faster to compute, it does not look anything like what I had in mind.. Goes to show I have so much more to learn when it comes to SMath! Cheers! rinks:
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Originally Posted by: mkraska Now with proper scaling
Just for show why the Martin solution it's correct: Best regards. Alvaro.
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Originally Posted by: hanskl Thank you Martin, this is exactly what I am looking for! Although your expression is both much simpler and much faster to compute, it does not look anything like what I had in mind.. Goes to show I have so much more to learn when it comes to SMath! Cheers! rinks: The approach was purely phenomenological, i.e. to reproduce the plots, no matter what they mean. The idea was to combine a sawtooth function and a linear term (slope). There are many options to get a sawtooth, the modulo function being just one of them. Others are round(), Floor(), Ceil()... The remainder was guessing the coefficients in a heuristic trial and error fashion. |
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Originally Posted by: Razonar Originally Posted by: mkraska Now with proper scaling
Just for show why the Martin solution it's correct: Best regards. Alvaro. Interessting. I have tweaked Martins equations - now n represents the number of loads, not the number of segments between loads/supports. Any idea why the integral gives me this result? Also, my integral is 10x the value of yours. Best regards,
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Originally Posted by: Jean Giraud Interesting stuff.. I will have a closer look at that when I have some spare time. Cheers
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Originally Posted by: mkraska Originally Posted by: hanskl Thank you Martin, this is exactly what I am looking for! Although your expression is both much simpler and much faster to compute, it does not look anything like what I had in mind.. Goes to show I have so much more to learn when it comes to SMath! Cheers! rinks: The approach was purely phenomenological, i.e. to reproduce the plots, no matter what they mean. The idea was to combine a sawtooth function and a linear term (slope). There are many options to get a sawtooth, the modulo function being just one of them. Others are round(), Floor(), Ceil()... The remainder was guessing the coefficients in a heuristic trial and error fashion. I thought that might be the case.. Anyways, it was purely to illustrate what happens when n approaches infinity, and your solution worked wonders for that! Thanks again
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Originally Posted by: hanskl Any idea why the integral gives me this result? Smath native Simpson integrator ranges from: 1. Exact only few trivial cases. 2. Acceptable but depending upon Options/Calculations/Int. acc set 1000 in your example. 3. Native Simpson may be TOTALLY useless. Sooner or later, units system collide in the wall. Discontinuous integration is poison in the soup. Master tool box has done all difficult projects except ONE ... The Inverse_Z transform. Cheers ... Jean Integrate Discontinuous [min(x)].sm (9kb) downloaded 11 time(s). Integrate Discontinuous_1.sm (25kb) downloaded 11 time(s). Integrate Discontinuous.sm (32kb) downloaded 10 time(s). Integrate Discontinuous_2.sm (133kb) downloaded 10 time(s). Integral 00000000 MASTER ToolBox.sm (477kb) downloaded 15 time(s).
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Originally Posted by: Jean Giraud Originally Posted by: hanskl Any idea why the integral gives me this result? Smath native Simpson integrator ranges from: 1. Exact only few trivial cases. 2. Acceptable but depending upon Options/Calculations/Int. acc set 1000 in your example. 3. Native Simpson may be TOTALLY useless. Sooner or later, units system collide in the wall. Discontinuous integration is poison in the soup. Master tool box has done all difficult projects except ONE ... The Inverse_Z transform. Cheers ... Jean Thanks again Jean.. I am baffled by the knowledge you guys possess here on the forum! Best regards, Hans Kristian.
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Originally Posted by: hanskl Thanks again Jean.. I am baffled by the knowledge you guys possess here on the forum!
At least, two of us are old kookoo from Mathcad. Smath learning curve has not revealed asymptotic. Two versions of the 3D rolling Torus. Rotate Torus [Ber7 20170922].sm (21kb) downloaded 10 time(s). Rotate Torus.sm (45kb) downloaded 11 time(s).
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Originally Posted by: Jean Giraud Originally Posted by: hanskl Thanks again Jean.. I am baffled by the knowledge you guys possess here on the forum!
At least, two of us are old kookoo from Mathcad. Smath learning curve has not revealed asymptotic. Two versions of the 3D rolling Torus. It took my computer about 3 minutes to compute this sheet..
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