When the FNA method is used for time history analysis, the mode needs to be read, and the effective stiffness is used for the modal analysis, so the small/medium/large earthquake levels should correspond to different effective stiffnesses. Frictional damping refers to the reduction of system energy in mechanical physics — not all damped oscillations are caused by “resistance”. As far as mechanical oscillations are concerned, one is heat generated by frictional resistance, which makes the system
The mechanical energy is reduced and converted to damping of internal energy. In short, frictional damping is a measure. It refers to the measurement of the degree of energy dissipated by the system due to frictional heat during frictional motion. Frictional damping is a measurement method, which refers to the measurement of the degree of energy dissipated by the system due to frictional heat during frictional motion.
Oscillation control has always been an important topic in modern industrial production. Due to the effect of friction Seismic Isolation Device For Earthquake Manufacturer on the dissipation of mechanical energy, friction damping is widely used in machinery manufacturing, aero-engines, civil engineering and other fields, so the study of friction damping characteristics is of great significance.
The energy loss of the oscillating system is mainly friction loss. According to the principle of energy conservation, the total mechanical energy dissipation is equal to the work done by friction. Ability to define frictional damping loss factors.
However, since the frictional work of a free oscillation system gradually decreases with time, and the motion characteristics of different systems are different, the energy loss in one cycle is used to calculate the loss factor. The loss factor can be expressed as where ΔE is the energy dissipated by friction during one cycle.
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