1.Why we need to study the
Strength of material subject?
·
Strength of materials, also called mechanics of
materials, is a subject which deals with the behavior of solid objects subject
to stresses and strains.
·
To predict the response of a structure under
loading condition and its susceptibility to various failure modes.
· Predicting properties of the materials such as yield
strength, ultimate strength, Young's modulus, and Poisson's ratio by various method
· Helps calculate the
stresses and strains in structural members, such as beams, columns, and shafts.
2. What is Load? Its
classifications?
·
A load is defined as combined effect of external
force acting on a body.
Classification of loads.
·
Point load
·
Distributed load
Other classification is
·
Tensile load
·
Compressive load
·
Torsional or twisting loads
·
Bending loads and shearing loads
·
Static load
·
Dynamic load
3. Classification of structure
based on the type of load they resist?
·
Bar- Resist axial loads both tensile and
compressive
·
Beam- Resist transverse loads
·
Truss (Collection of bars) - Resist axial loads
both tensile and compression
·
Shaft- Resist torsional loads
·
Columns- Resist axial compressive loads only
4. What is mean by rigid body?
·
A rigid body does not undergo any deformation.
·
It is hypothesis only. In real life all bodies
are elastic and deformable up to a certain limit.
5. Define an
elastic body.
·
The strains which disappear with the removal of
load, this type of body is called elastic body.
6. Define stress.
The internal resistance which the body offers to meet
with the load is called Stress.
Ratio between Internal resisting
forces per area perpendicular to the direction of force.
σ =P/A
7.What type of stresses occurring
in a structure?
1.
Direct stress or simple stress
o
Tension stress
o
Compressive stress
o
Shear stress
2.
Indirect stress
o
Bending stress
o
Torsional stress
3.
Combined stress
8. What is shear stress?
·
Ratio of Internal resisting force (shear force)
to area parallel to the direction of force.
Ratio between Internal resisting forces per area perpendicular to the direction of force.
τ=V/A
9. Explain strain.
Deformation produced by the stress
Ratio of Change in length to the
original length.
Normal strain = Change in length /
original length
ϵ = δL / L
Where,
ϵ - Normal strain
δL - Change in length
L
- Original length
10. Various types of strain.
·
Tensile Strain
·
Compressive strain
·
Shear strain
·
Volumetric strain
