D - Pre-Event Management Flashcards
List three methods to reduce landslide risks.
Terracing steep slopes, improving slope drainage, and constructing restraining structures like stone walls.
How can erosion control help manage landslide risk?
By protecting the base of cliffs or slopes from undercutting, reducing the chance of slope failure.
Why are single-storey buildings generally safer in earthquakes?
They sway less than multi-storey structures and are less prone to collapse.
What is a ‘soft storey’ in earthquake-resistant design?
A collapsible lower level (often a parking area on pillars) that absorbs the impact of upper floors sinking onto it.
Explain ‘basement isolation’ in seismic design.
Foundations are mounted on rubber bearings, allowing the ground to move beneath the building while the structure remains stable.
Name two ways buildings can be reinforced against earthquakes.
Building deep foundations on bedrock and using steel frames capable of withstanding shaking.
Besides construction methods, how else can earthquake risk be reduced?
Through land-use planning, such as avoiding building in high-risk zones or on unstable ground.
What are two ways to manage or divert lava flows?
Using channels or explosives to redirect lava, or pumping water onto the lava front to cool it.
Why is it difficult to manage pyroclastic flows?
They move rapidly and are extremely hot, so evacuation is generally the only effective method.
How can GPS help in volcanic risk management?
By monitoring volcano swelling, which may indicate rising magma and an imminent eruption.
How are tsunamis generally managed?
Through sea walls and early warning systems.
What limitation do sea walls have in tsunami management?
Their height is limited by cost, so they can only provide protection up to a certain wave size.
