Uploaded by Jithesh S.R

CantileverBeamProblem

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DEPARTMENT OF MECHANICAL ENGINEERING
Ex: CAA-01-Q1
Structural Analysis of a Loaded Cantilever Beam
Question
Loading on a cantilever beam (Rectangular section: 0.1m x 0.1m) is shown in figure. Find
the max. deflection, shear force and bending moment of the cantilever beam.
Loading: 1500N downwards at mid-point from fixed end (hint: Point load)
3000N downwards at free end (hint: Point load)
UDL – 1000N/m downwards upto mid-point from fixed end (hint: Edge load)
COMPUTER AIDED DESIGN AND ANALYSIS LABORATORY
DEPARTMENT OF MECHANICAL ENGINEERING
Ex: CAA-01
Structural Analysis of a Loaded Cantilever Beam
Aim
To find maximum deflection, shear force and bending moment of a loaded (Point loads and
Uniformly Distributed Load) cantilever beam.
Tools used
Grid, Geometry-Keypoints, Geometry-Curve, Mesh, Load/BC-Displacement BC, Load/BCPoint Load, Load/BC-Edge Loads, Property-Material, Property-Physical, Analysis, Run
Solver, Post tools etc.
Steps involved
Step-1: Setting Grid
The FEASTSMT Analysis software was opened and set ‘Grid’ from ‘Settings’ (last tab
on Control panel) > Grid as per requirement.
Step-2: Creating geometric model
In 'Main' (first tab on Control panel),
Commands > Geometry > Key point > Create > By X/Y/Z
Parameters for the command (shown below the Control Panel)
Required coordinate data was entered to create three points P1(0,0,0) and P2 (1,0,0).
Geometry > Curve > Create > Line.
Also ‘Snap to point’ (Below the Control panel) was selected.
Parameters for the command
A line (i,e, a beam of 1m length) was drawn by selecting previously created points
(P1 and P2).
Step-3: Meshing the geometric model
Mesh > FE Mesh > Bar
Parameters for the command
Previously drawn line was selected with suitable ‘Subdivisions’ (Say, 10).
COMPUTER AIDED DESIGN AND ANALYSIS LABORATORY
DEPARTMENT OF MECHANICAL ENGINEERING
Step-4: Applying boundary constraints
Load/BC > Displacement BC > Add
Parameters for the command
Point P1 was selected as ‘Node IDs’, which is the fixed end of the cantilever beam
and all degrees of freedom (DOF) was set to zero (‘BC values’ set as Translation:
Ux=Uy=Uz=0 and Rotation: Rx=Ry=Rz=0).
Step-5: Applying Load
Load/BC > Point Load > Add
Parameters for the command
The node (‘Node IDs’) on the midpoint of the line (beam) was selected, applied
suitable load value (‘Data’) and direction (‘Component’).
Node IDs: The node at mid-point of the beam
Data: -1500 (Numerical value in Newton)
Component: Fy
Repeated the same procedure for the node corresponding to the free end of the beam
with Data: -3000 and Component: Fy.
Load/BC > Edge Loads > Add
All nodes from fixed end upto mid-point of the beam were selected (‘Element edges’),
applied suitable load value (‘Edge load data’) and direction (‘Direction’).
Parameters for the command
Two nodes (‘Node IDs’) were selected, applied suitable load value (‘Data’) and
direction (‘Component’).
Element edges: 1T5(D1)
Data: -1000 (Value in Newton)
Direction: Normal to edge.
COMPUTER AIDED DESIGN AND ANALYSIS LABORATORY
DEPARTMENT OF MECHANICAL ENGINEERING
Step-6: Adding material to the model
Property > Materials > Structural > Isotropic > Add
Parameters for the command
All elements (line) was selected and required material data was entered.
Element IDs: All [Click ‘All’ (Tool bar below the Control panel)]
Material-Data: 2E+11/0.3/0/0/0
(For Steel, Modulus of elasticity: 200GPa and Poisson’s ratio: 0.3)
Note: Material data can be retrieved from the Materials library of the software, if
available, otherwise enter user specified values of relevant properties.
Step-7: Setting physical properties
Property > Physical > Beam properties > Standard section > Add
Parameters for the command
Parameters of the beam cross section (Rectangular) were added.
Element IDs: All
Cross-section shape: RECT/0.1/0.1
[Click the button ‘dialog box’ next to ‘Cross-section shape’, ‘Beam sections’ dialog
box was opened, set ‘Shape’ as ‘RECT’ and dimensions, both ‘b’ and ‘h’ values as
0.1 (i.e, 0.1 m)]
Step-8: Setting analysis type
Analysis > Analysis Type
Parameters for the command
Set analysis type as ‘Static’.
Step-9: Analysing/Solving the problem
Analysis > Run Solver
Or click on ‘!’ (‘Run solver’ button placed on the tool bar).
COMPUTER AIDED DESIGN AND ANALYSIS LABORATORY
DEPARTMENT OF MECHANICAL ENGINEERING
Step-10: Post processing of analysis/solution
Post > Beam Plots > Force diagram
Parameters for the command
For shear force diagram
Component: SHEAR1
Plane: Plane-1
For bending moment diagram
Component: BM2
Plane: Plane-1
Watched the animation of the deflected beam.
Post > Deformed shape
Maximum deflection of the beam was obtained.
Options available are ‘Superimpose’ (shows original position of the beam), ‘Highlight
maximum’ (maximum deflection of the beam) and ‘Animate Deflection’.
Result
Hence the analysis (shear force and bending moment) of the loaded cantilever beam was
done.
Maximum deflection at free end
= 0.00071092 m (or 0.71 mm)
Maximum shear force
= 4.95 kN at fixed end
Maximum bending moment
= 3.875 kNm at fixed end
COMPUTER AIDED DESIGN AND ANALYSIS LABORATORY
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