# Help with a Beam Equation and Drawings

• LareeRudi
In summary, the conversation includes a request for help with creating a Shear Diagram, a Moment Diagram, and finding the maximum deflection value for a beam equation. The beam is 11.00 ft long and has point loads at specific distances from each end. The speaker is looking for assistance in creating these diagrams and is open to emailing details to receive a solution. References for additional information are also provided.

#### LareeRudi

I might be in the wrong place, let me know where to go [kindly, ha] if I am.

I havn't had math and physics etc since 1956 and never had the course "Strength of Materials"; I have a beam equation that I'd like answers to; it's not for a test, nor anything but my info, and I'd like some help drawing a Shear Diagram, a Moment Diagram, then to find the max deflection value.

If there is a more "Structural" forum that you know of, let me know. Else if I HAVE any takers here, let me know. The problem is not easy to diagram as I have no tools to DO IT. So it'll have to be all words, carefully presented.

The beam is freely supported at each end and is 11.00 ft long.

There are POINT loads [I don't want to approximate a uniformally loaded problem; I want it to be specific for these loads].

In from the left end 0.5 ft is a load of 75 lbs, in 1.5 ft is a load of 70 lbs, in 2.5 ft is 65 lbs, in 3.5 ft is 60 lbs, in 4.5 ft is 55 lbs, and in 5.5 ft [the middle] is 50 lbs, then the loading is symetrical, starting in from the right, 0.5 ft is 75 lbs, in 1.5 ft is 70 lbs, etc; total load of 700 lbs if I can still add correctly. So of course then I'd have 350 lbs on each end, but I can't get STARTED to even find the Shear forces as they increase/decrease towards the middle, then of course, same thing on creating a Bending Moment Diagram and then, a deflection equation, please.

If you can help, help me and thanks, if you've got to send me away, do it kindly, ok?

Thanks,

LarryR : )

If you could describe the beam is it an I beam? rectangular? you should sketch the details on a page and scan it and email it to me. I can then send you the solution.

I could sort this whole problem out if you give me that. I presume if its a steel s275 beam yea?

I can tell you already shear will not be a problem for an 11ft beam given that it has sufficient depth.

The max shear on this beam is on the edges where it is being supported and the value of max shear is 350lbs.

Don't laugh, but you can chuckle, ha. It's a 2 x 6, or 2 x 8 etc, so see, that is not part of the question. I'm wanting to learn how to create the shear diagram [even tho it's not going to break; I just want to know HOW to do it]. Then once the shear diagram is created, I'm wanting to learn HOW to create the Moment diagram.

So if it's a steel beam, joist, or a railroad tie, you see, I just want to know how to create those diagrams, then to find the deflection.

I'll try to figure out how to email you. And I thank you for your willingness to help.

LarryR : )

microbiek said:
If you could describe the beam is it an I beam? rectangular? you should sketch the details on a page and scan it and email it to me. I can then send you the solution.

I could sort this whole problem out if you give me that. I presume if its a steel s275 beam yea?

I can tell you already shear will not be a problem for an 11ft beam given that it has sufficient depth.

The max shear on this beam is on the edges where it is being supported and the value of max shear is 350lbs.

alright no problem...its not too hard to make the shear and moment diagrams i have a good pdf that i downloaded from an american university called wisconsin i think? but its really good and explains fully how to create bending moment diagrams and shear force diagrams.

i can email that to you.

to quickly demonstrate in words like yourself how easy an SFD is a horizontal line represents the beam on the very left you draw a line straight up and mark it as 350lbs...

as the max shear is on the edges and this is gotten by the (total load/2)

moving in from the left end say 2 ft in you have a 50lbs weight then from your 350 line draw a line horizontally over until you reach where the 50lbs weight acts...

Then a vertical line downwards to the value of 300lbs as the shear suffered by the beam by this weight acts down i.e. the shear values tend towards 0 as you get closer to midspan.

bending moments however are a maximum at midspan!

Essentially in this instance it will be a step like SFD...any way i dint know if I am any use at explaining but the PDF has visual aids so it should do the trick for you...just need your email.

Here are links to some reference information that might help:

http://www.awc.org/pdf/DA6-BeamFormulas.pdf

http://oak.cats.ohiou.edu/~williar4/html/HapEd/NSF/Stat/Beam.pdf [Broken]

http://ocw.mit.edu/NR/rdonlyres/Materials-Science-and-Engineering/3-11Mechanics-of-MaterialsFall1999/Modules/statics.pdf [Broken]

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hotvette said:
Here are links to some reference information that might help:

http://www.awc.org/pdf/DA6-BeamFormulas.pdf

http://oak.cats.ohiou.edu/~williar4/html/HapEd/NSF/Stat/Beam.pdf [Broken]

http://ocw.mit.edu/NR/rdonlyres/Materials-Science-and-Engineering/3-11Mechanics-of-MaterialsFall1999/Modules/statics.pdf [Broken]

Thanks a million; that top one REALLY helped. Thanks to you and others that are emailing me, I'm beginning to get a grasp on it.... I'm graduating now to "overhung" loads, ha.

Truly, thanks.

LarryR : )

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## 1. What is a beam equation?

A beam equation is a mathematical formula used to calculate the deflection, stress, and other properties of a beam under different loading conditions. It is an essential tool in structural analysis and design.

## 2. How do I solve a beam equation?

To solve a beam equation, you need to first determine the type of beam (e.g., cantilever, simply supported) and the type of loading (e.g., point load, distributed load). Then, you can use appropriate formulas or software to calculate the deflection, stress, and other properties.

## 3. What are the most common beam equations used in engineering?

Some of the most common beam equations used in engineering include Euler-Bernoulli beam equation, Timoshenko beam equation, and the moment-curvature equation. These equations vary in their assumptions and can be used for different types of beams and loading conditions.

## 4. What is the importance of drawings in solving beam equations?

Drawings, such as free body diagrams and shear force and bending moment diagrams, are crucial in solving beam equations. They help visualize the loading and boundary conditions, which are essential for determining the correct beam equation to use and for setting up the equations for solving.

## 5. Can beam equations be used for real-world applications?

Yes, beam equations are widely used in real-world applications, particularly in the design and analysis of structures such as bridges, buildings, and aircraft. They provide engineers with valuable insights into the behavior of beams under different loading conditions, helping them ensure the safety and stability of structures.