A Comparative Study On The Equivalent Base Shear Method In The Codes For Seismic Design Of Buildings In China And Japan

The Seismic Design Code in a country reflects its level of research and practical experience on seismic. When the earthquake comes, with a better seismic design philosophy, the destruction on buildings can be decreased greatly, the economic losses of property can be reduced dramatically and people’s lives and safety can be protected effectively as well. We must first of all realize that deficiencies still exist in terms of seismic design in our country, and thus in our development be tolerant to diversity, learning advanced theories from other countries in the seismic field. Only in this way can our seismic design of buildings be more perfect.In this thesis, the main provisions of Seismic Design Code in the two Chinese versions ——Version 10 and Version 01 are compared and analyzed. Subsequently, a brief introduction about those in Japan is conducted. In the last part, with different provisions from three versions, analysis and comparison is made on the seismic design calculations of an eight-floors frame structure. The conclusions are as follows:(1) In consequence to the increase in the building seismic intensity, equivalent base shear values, floor shear values, and floor displacement values figured out in both Version——01 and Version——10 are enlarged. The difference lies in the fact that in Site I equivalent base shear values calculated in Version——01 are larger than those in Version10; whereas in Site II, III, and IV, the results are identical in both versions. And with the increase of classifications in the foundation sites, equivalent base shear values are dramatically increased.(2) As site classifications increase, floor shear values and interlayer displacement calculated in both versions go up accordingly. However, Site I, by showing a higher level in floor shear values and interlayer displacement in Version01, is an exception.(3) Under the same building seismic intensity and in the same sites, floor shear values and interlayer displacement goes down as the height of buildings increases. In Site I, with the increase in height, floor shear values and interlayer displacement in Version——10 are always less than those calculated in Version——01.(4) The building seismic intensity rising, the equivalent base shear values, floor shear values, and interlayer displacement calculated in both Japanese and Chinese versions also increase. What is different is that the increase in the Japanese Code is greater than that in the Chinese Code. With the increase of the site classifications, equivalent base shear values in the Japanese version first goes up and then remains unchanged. However, in the Chinese version, equivalent base shear values have always been increasing.(5) With the increase of site classifications, floor shear values and interlayer displacement calculated in the Codes form two countries go up as well. But those in Chinese Code have a faster increasing speed than those in Japanese Code.(6) In the Codes from two countries, under the same seismic intensity and in the same site, floor shear values and interlayer displacement decreases, following the increase in the height of the buildings. The distinction is that floor shear values, as shown in the Japanese Code, decrease in a slower speed. Another distinction is that in Japanese Code, the decrease in interlayer displacement in Site I and II happens much faster. In Site III and IV, the speed of that in both Codes keeps the same.