15-09-2016, 09:50 AM
1454523386-baseisolationusingperiodicfoundation1.ppsx (Size: 5.11 MB / Downloads: 3)
INTRODUCTION
Earthquakes are one of the worst natural calamities.
Causes instantaneous destruction of property and loss of life.
During an earth quake, principal attack on a structure is by transient horizontal force.
BASE ISOLATION SYSTEMS
One of the most effective means of protecting structure from earthquakes
Decouples the structure from horizontal ground motion induced by earthquakes
Increases the natural time period of vibration
DRAWBACKS OF TRADITIONAL BASE ISOLATORS
Building will have large residual horizontal displacement relative to foundation after an earthquake
The vertical bearing capacity of the rubber base is relatively poor which may result in yielding of isolation support
The effect of soil-foundation interaction is ignored
EXPERIMENTAL STUDY
Scaled model of the periodic foundation were tested using shake table
Tests were conducted at the National Centre for Research on Earthquake Engineering, Taiwan
Results were compared with specimen having no periodic foundation
CONCLUSION
Performance of a periodic foundation depends on LEF, UEF and FGW.
High density of core and increase in filling fraction decreases LEF.
High density of core and increase in filling fraction increases FGW.
With proper design, a periodic foundation made using common engineering materials is found to be more effective in base isolation compared to traditional rubber bearings