What are the three methods countries use to defend against earthquake damage?  

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One method used by the United States is to plan infrastructure in locations that have lower earthquake risks and/or appropriate soil. This method is achieved through USGS produced earthquake risk maps, which can then serve as a delimiting factor for land use planning by politicians (and city planners). When selective land use planning reaches its limitation highways that cut across earthquake prone areas have also been retrofitted with cable supporters (that reinforce the joints between road segments), hinge restraints (that reinforce the connection between the roads and the columns), steel casing around the columns, a layer of grout between the concrete column and steel casing, widening the footing underneath the columns and deepening the pilings further into the soil.

Another method that is used in Japan are building regulations which give skyscrapers the pliability to sway with the earthquake instead of collapsing from rigidity. This architectural (or technological) method is implemented through two techniques. The first incorporates shock absorbers into the foundation of the building, where the second technique partially segments the top portion of the building from a base structure. Other components for building earthquake resistant structures also include cross-bracing (steal beams that cut across to connect the walls) and shear walls (steel bars inside of concrete walls). 

A method used in China is earthquake monitoring and warning systems. The most pervasive monitoring systems is by (digital) seismological observations, which are regionally collected and then transmitted to the national level via satellite.  Computer detection of tremors on the land (as well as the ocean and the ocean-bed) then provide a small timeframe (as in a few seconds or minutes at most) for sending warning and/or implementing evacuation responses. 

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