The Statistical Property Of Mainshock-Aftershock Sequences Of Wenchuan Earthquake And Its Impact On The Structures

The aftershock often happens after the main-shock, and it has a considerate impact on the structures. The main-shock can also be considered a kind of foreshock relative to the aftershocks.On May12th2008the Wenchuan earthquake happens, which is the most serious earthquake in the history of China, making a lot of death and loss. This earthquake is worth being focused because it has some distinctive characteristics including the high intensity, the broad range of impact etc. We get lots of recordings in Wenchuan earthquake, including main-shocks recorded by420seismographs and aftershocks recorded by77fixed seismographs and86unfixed seismographs.There are some differences between the Chinese seismic code and the U.S. code. In chapter four of this thesis, two structures which were designed in conformance with the seismic codes respectively are analyzed, and some useful conclusions have been reached.Based on the background above, the thesis includes the following contents:(1) Research on the attenuation rules of PGA in the Wenchuan earthquake along with the fault distance and the peak ground acceleration relationship between the main shock and the aftershock;(2) Research on the impact of the aftershock on the structural response;(3) Using IDA and PUSHOVER methods to analyze two structures in order to compare the Chinese and U.S. seismic code.