General Idea of Truss and analysis of it through Method of joints

1. Analysis of Truss
Dr. Nitesh Mondal
Mechanical Engineering Department
Email: niteshmondal.mech.rs@jadavpuruniversity.in

2. Truss
Assumption:
• Truss members are connected together at their ends
only.
• Truss members are connected together by pins which
is frictionless.
• The truss is externally loaded at the joints only.
• The weights of the members are neglected for the
analysis.

3. Simple Stress
• The basic building block of a truss is a
triangle.
• Large truss are constructed by attaching
several triangles together ,A new triangle can
be added truss by adding two members and a
joint.
• A truss constructed in this fashion is known
as a simple truss.

4. Method of Joints
Method of joints means of solving force inside
of the truss use equilibrium equations at a joint.
This method is known as the method of joints.
• Conditions of equilibrium are satisfied for the forces at each joint.
• Equilibrium of concurrent forces at each joint
• Only two independent equilibrium equations are involved
• Forces on the joints are –Compression, Tension and no force.
Force from the joint- Tension
Force to the joint- Compression
Tension Compression

5. Steps of Analysis:
1.Draw Free Body Diagram of Truss
2.Determine external reactions by applying equilibrium
equations to the whole truss
3.Perform the force analysis of the remainder of the truss
by Method of Joints
Draw Free Body Diagram

6. Example:1
Determine the force in each member of the loaded truss by Method
of Joints

9. Thank You