Loading

1
I.I- Introduction
Loading
Structure
Response
1- Analyzing structures under dynamic
loading 2-Codes and beyond
i- Loading
a- Types of dynamic loading
1-Periodic (repetitive loading) such as rotating
machinery in a building
2-Non-Periodic such as blast, earthquake, and wind
2
b- Characteristics of a dynamic loading
1-No single solution (function in time)
3
b- Characteristics of a dynamic loading (contd)
2-Inertia loads are developed in dynamic loading
ONLY
ii- Structure
a- Structure modeling
4
b- Degree of freedom
1-The number of independent displacement required
to define the displacement position of all the
masses relative to their original position
iii- Response
5
a- Damping
Process by which vibration steadily diminishes in
amplitude.
b- Sources of damping
1-Friction 2-Opening and closing of micro
cracks 3-Impact and energy radiation, etc.
It is almost impossible to identify
mathematically each energy dissipating mechanisms
in an actual building. We may represent all
damping by a single idealized equivalent viscous
damping
6
c- Static force
d- Equivalent stiffness