Comparison of Bending in Beams : Rectangular Section, I-Section & C- Section
Aim
To compare the bending performance of three types of beams
- Rectangular Section
- I-section
- C-section
Objective
- create the sketches shown below in Solidworks
- extrude the sketches to a length of 400mm
- Apply a load of 1500N on the smaller face
- 45mm face for case 1
- 40mm face for case 2
- 45 mm face for case 3
Theory
- FEA(Finite Element Analysis)
FEA is an analysis method using FEM(Finite Element Method) to solve the structural problems. The finite element method is a numerical technique for obtaining an approximate solution to a wide variety of engineering problems. The method originated in the aerospace industry as a tool to study stresses in the complex air-frame structure.
Since its birth, the finite element method has gone through various developmental stages. Started with the formulation of finite element theory, variational and Galerkin's approaches for two dimensional and three-dimensional problems were formulated. Isoparametric formulations for both linear and non-linear, static and dynamic analyses were developed. Also, computational methods required by the finite element method were established. This method includes numerical integration of element equations, a solution of the global system of algebraic equations, the study of numerical stability and error analysis solution algorithms.
- Stress
When a body is acted upon by an external force or load, internal resisting force is set up, such a body is said to be in a state of stress, hence stress is the resistance offered by the body to deformation.
- Strain
when a force or load acts on a body it undergoes deformation. This deformation per unit length is known as unit strain or simply strain.
- Bending of Beams
In applied mechanics, bending (also known as flexure) characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to a longitudinal axis of the element
Procedure
On these 3 types of beams created according to the dimension given and perform a static analysis on the simulation of solid works. as mentioned earlier the forces and fixed geometries are given. then create a fine mesh and run the simulation. the output of the simulation has displacement, stress and strain with the plots.
Material - Alloy steel
Mesh Type - Fine Mesh
Force Applied - 1500 N
Model Created
- Case 1
- Case 2
- Case 3
Results
- Case 1
- Case 2
- Case 3
Conclusion
If we compare the stress plots, maximum stress-induced is less on the rectangular beam then on the I section and is maximum at the C-section beam. Strain figures indicate that maximum change in length takes place in the C-section beam and minimum change in length occurs in the I-section beam and the displacement plots indicate that minimum displacement occurs in the rectangular beam after application of 1500N and maximum displacement occurs in the C-section beam. It can be seen that the C-section beam is subjected to torsion, therefore, it is the least preferred among the three beams. Since stress-induced in both the I-section and rectangular beam is under the yield strength therefore both the beams will sustain the force of 1500N properly without failing, but if we look at the distribution of stress, it is quite evenly distributed in the I-section, which I feel will withstand larger force as compared to the rectangular beam.
So, I would prefer the I-section beam as the best of the three beams.