Seismic retrofit Seismic retrofit Seismic retrofitting is the modification of existing structures to make them more resistant to seismic activity, ground motion, or soil failure due to earthquakes. With better understanding of seismic demand on structures and with our recent experiences with large earthquakes near urban centers, the need of seismic retrofitting is well acknowledged. Prior to the introduction of modern seismic codes in the late 1960s for developed countries (US, Japan etc.) and late 1970s for many other parts of the world (Turkey, China etc.), many structures were designed without adequate detailing and reinforcement for seismic protection. In view of the
Seismic Experiment for Interior Structure has large marsquakes, they may allow the deep interior to be determined. As the vibrations pass through the planet they are affected by the properties of the materials and its configuration. For example, the effect of tidal forces on Mars by Phobos, which should be about 10 mm, would be noticeably affected by a liquid Mars core. Even without any marsquake, it should be possible after about six months of observation to use this method to increase or decrease the likelihood Mars has a liquid core. Seismic Experiment for Interior Structure The Seismic Experiment for Interior Structure (SEIS) is a