Earthquake is sudden and has very low predictability, to the serious loss of human society, is the most serious types of natural disasters, the disasters. According to the current level of science in China and economic conditions, Seismic proposed "three levels" of fortification goal, known as "minor earthquake, the earthquake can repair, earthquake did not fall." Usually about a small earthquake, the earthquake, earthquake, respectively referring to the probability of exceedance in 50 years, 63%, 10%, more than 2 to 3% of the earthquake, seismic fortification intensity, strong earthquake. A structure designed to determine the earthquake forces 1.1 The feasibility of low seismic force values Twentieth century, the eighties, both countries recognize the design of such a fact that in the earthquake, structural failure in the real before, there is a large plastic deformation capacity (ductility), namely the structure of a smaller earthquake in or close to the yield potential under the state; in larger earthquakes, the structure of certain positions will have moved into post-yield inelastic deformation, and with the seismic force increases, the structure of the site into plastic deformation increased first enter the site of plastic deformation of yield increase. Dissipation through deformation of the structure of this earthquake came more energy to convert it into heat.