FEMUR BONE STRESS ANALYSIS -USING ABAQUS SOFTWARE
A Simplified overview of the whole implementation.
What is the Femur bone and its uses to the human body system.
The femur is your thigh bone. It’s the longest, strongest bone in your body. It’s a critical part of your ability to stand and move. Your femur also supports lots of important muscles, tendons, ligaments and parts of your circulatory system.
What does the femur do?
Your femur has several important jobs, including:
- Holding the weight of your body when you stand and move.
- Stabilizing you as you move.
- Connecting muscles, tendons and ligaments in your hips and knees to the rest of your body.
What causes femur fractures?
Bones break when there’s more force applied to a bone than it can absorb. Fractures can occur from a fall, trauma, or direct blow.
Most childhood femur fractures result from:
- falling, for instance, from stairs or a jungle gym
- moderate to severe trauma that may happen in a car accident or during contact sports
Femur fractures in infants (up to 1 year old) are unusual, but can be caused by:
- osteogenesis imperfecta and other medical conditions that cause weak bones
- a very difficult delivery
- child abuse
The whole implementation is mainly about apply stresses on a femur design to know its breaking point which helps in designing for patients with femur fracture.
Main software used was Abaqus
How to install Abaqus — I have provided youtube links and links to that effect.
Modeling a femur bone in Abaqus CAE
Abaqus is one of the many software’s used for finite element analysis.
· Creating the femur part
1. Abaqus loads the module part. Any other module can be accessed from the drop-down
2. From the main menu bar, select Part-Create to create a new part (which is femur).In the create part, name the part Femur, and give an approximate size
Accept the default settings of a 2-D deformable body with a solid. And click continue
3. To sketch the femur you need circles and curves.
4.The final sketch is as follows
5. Click done in area to exit the sketcher .The 2-D model is generated
5.Creating the material definition
6. Assigning section properties
7. Assembling the femur model and hence creating instance
8. Creating general static analysis step.
9. Applying boundary conditions to one end of the femur;
10. Applying load on top of the femur;
Explanation of why stress magnitude is 1888.7 MPa in my model;
Stress magnitude=(Plane stress)⁄(strain thickness)
NB. The average weight of an adult human is 62 kg.
Force
62kg*9.8g=607.6 N
Strain thickness. =607.6⁄(3.142*〖(0.00032)〗² )
=1888.7 MPa
Radius of the curves used in the sketches is approximately 0.32 mm=0.00032m
11. Meshing the femur model
*From the main menu select seed-part to seed the femur part
*Click Ok
- Finally meshing the femur
11.Creating and submitting an analysis job
12. Results after job is submitted and completed;
Deformed femur model
- Undeformed femur model
Deformed shape
