Managing The Earthquake Hazard Homework 07
Managing the earthquake hazard Homework 07/03/15
Mitigation: Modify the event
1. How realistic is the control of the physical earthquake event?
Control of the earthquake event itself and physical variables such as the location of the epicentre, depth of the focus, foundation material ie rock type, duration of shaking and time of day is not a realistic form of management. Earthquakes caused by humans on the other hand such as those resulting from dam destruction can be managed by considering the seismic hazard hen creating the structures.
2. What is ‘aseismic’ building design?
The impact of hazards can be reduced by incorporating earthquake resistant or ‘aseismic’ design features. Buildings made of mud brick (adobe) or other materials without reinforcement will collapse easily during an earthquake. In multi storey buildings the shaking can be increased with height as the building moves. Techniques and regulations are constantly being updated and improved. However some buildings may not be as safe as once thought. Examples of aseismic deign includes a large concrete weight on top of a building activated by computer controlled dampers which moves in the opposite direction to the force of the earthquake to counteract stress in the structure. Total power failures means the block can’t be moved. Large rubber shock absorbers can be planted into the foundations to allow the building to rock back and forth without causing too much damage to the structure. By adding eccentric cross-bracings to a structure the building becomes more ductile and can respond to pressures from earthquakes, minimising damage. An aseismic design is less likely to collapse on its occupants-it doesn’t mean that the structure is not damaged beyond repair. Economic losses therefore remain high ans continue to rise as more expensive techniques are used when rebuilding.
3. Examples of how aseismic design can reduce the earthquake hazard
MEDC’S:
Seismic Isolators-A combination of two
Mitigation: Modify the event
1. How realistic is the control of the physical earthquake event?
Control of the earthquake event itself and physical variables such as the location of the epicentre, depth of the focus, foundation material ie rock type, duration of shaking and time of day is not a realistic form of management. Earthquakes caused by humans on the other hand such as those resulting from dam destruction can be managed by considering the seismic hazard hen creating the structures.
2. What is ‘aseismic’ building design?
The impact of hazards can be reduced by incorporating earthquake resistant or ‘aseismic’ design features. Buildings made of mud brick (adobe) or other materials without reinforcement will collapse easily during an earthquake. In multi storey buildings the shaking can be increased with height as the building moves. Techniques and regulations are constantly being updated and improved. However some buildings may not be as safe as once thought. Examples of aseismic deign includes a large concrete weight on top of a building activated by computer controlled dampers which moves in the opposite direction to the force of the earthquake to counteract stress in the structure. Total power failures means the block can’t be moved. Large rubber shock absorbers can be planted into the foundations to allow the building to rock back and forth without causing too much damage to the structure. By adding eccentric cross-bracings to a structure the building becomes more ductile and can respond to pressures from earthquakes, minimising damage. An aseismic design is less likely to collapse on its occupants-it doesn’t mean that the structure is not damaged beyond repair. Economic losses therefore remain high ans continue to rise as more expensive techniques are used when rebuilding.
3. Examples of how aseismic design can reduce the earthquake hazard
MEDC’S:
Seismic Isolators-A combination of two