What is the maximum bending moment for this beam?

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SUMMARY

The maximum bending moment for the beam with overhanging supports, a uniformly distributed load (UDL) of 40 N/cm, and a point load of 14 kN is determined through both graphical and analytical methods. The total equivalent load from the UDL is calculated as 11,200 N, which acts at the center of gravity of the UDL. The reactions at the supports, denoted as F_A and F_B, can be computed using static equilibrium equations. Understanding the impact of the UDL's position relative to the supports is crucial for accurate bending moment calculations.

PREREQUISITES
  • Understanding of static equilibrium principles
  • Familiarity with beam loading conditions, including UDL and point loads
  • Knowledge of bending moment diagrams
  • Ability to perform unit conversions in mechanics
NEXT STEPS
  • Study the calculation of support reactions for beams with varying load distributions
  • Learn how to construct bending moment diagrams for beams with overhangs
  • Explore the effects of load positioning on bending moment calculations
  • Investigate the differences in analysis for beams with and without overhangs
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Engineering students, structural analysts, and anyone involved in mechanical design or civil engineering who needs to understand beam mechanics and load analysis.

Antex
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Homework Statement



Problem: For the beam according to the image, solve graphical and analytical:

1.) Reactions in the supports,
2.) Bending moment diagram,
3.) Maximum bending moment

Given variables:
F = 14 kN
q = 40 N/cm
a = 100 cm
b = 55 cm
l = 180 cm

TS2dfMZ.png

Homework Equations


This is a Beam with both overhanging supports, with a UDL and a point load on the right overhang. And I cannot find information for solving this.

Sorry for my terminology, I am doing physics in another language.

I am having a lot of trouble with the solving of this problem. What really confuses me is the UDL (I hope this is the correct terminology) that isn't over the entire beam, but hangs off on the left side.

I can't find any problems in my book that solve this kind of problem, and the professor didn't go into detail.

The Attempt at a Solution



This is a Beam with both overhanging supports, with a UDL and a point load on the right overhang.

My attempt at this was trying to figure out the force F_{q}, with: F_{q} = q*l => 40 * 280 = 11200 N/cm, 112 N/m, 0,112 kN/m

And assuming that the above is correct, which I do not know, I can go ahead and find F_{A} and F_{B}
 
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Antex said:
My attempt at this was trying to figure out the force F_{q}, with: F_{q} = q*l => 40 * 280 = 11200 N/cm, 112 N/m, 0,112 kN/m

And assuming that the above is correct, which I do not know, I can go ahead and find F_{A} and F_{B}
The numbers are right, but not the units. If you multiply N/cm by cm what do you get?
 
haruspex said:
The numbers are right, but not the units. If you multiply N/cm by cm what do you get?

Just N?
 
Antex said:
Just N?
Yes.
 
haruspex said:
Yes.

Could you explain me the difference if there was no overhang at A, and the UDL ended at A? Is there a different process in calculation in that case?

And also: 11200 N is then 112 kN? or would it be N/m and then 1.12 kN?
 
1. The difference is in the position where Fq "grabs". Otherwise same calculation.
2. No: 11200 N = 11200 N / (1000 N/kN)
or if you are word-oriented: eleven thousand 200 = eleven thousand plus (200 * thousand/thousand) = (eleven plus 200/thousand ) * thousand​
 
Antex said:
Could you explain me the difference if there was no overhang at A, and the UDL ended at A? Is there a different process in calculation in that case?

And also: 11200 N is then 112 kN? or would it be N/m and then 1.12 kN?
When determining the support reactions, the UDL can be represented by a single concentrated load of 11,200 N acting at the center of gravity of UDL, that is, at (a + l)/2 from the left end of the beam.
 

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