Chapter 3 - Vibration Theory Flashcards
What is natural period?
It is the time required to complete a full cycle of vibration
What is the response spectra?
A collection of response spectrum for variety of damping ratios and soil types
what is stiffness?
the force required to produce a unit displacement in the direction of the force
what are the two different ways that stiffness can present itself?
in parallel OR in series
what is the formula for stiffness?
aka rigidity
stiffness = force / deflection
what is the constant for gravitational constant?
- 32.2 ft/sec^2
- 386 in/sec^2
what is damping?
a frictional resistance which dissipitates the energy of the system, primarily through friction
w/o damping, then SDOF will oscillate indefinitely
what is critical damping?
the amount needed to bring the system back to normal in the shortest amount of time
what is a response spectrum?
a graph which plots all of the maximum responses (position, velocity, acc) of a structure with certain damping ratio to a particular ground motion
what is base shear?
the maximum force imparted to the structure from an earthquake
how long is the long period? TL
greater than 6 seconds
