Assessment of structural performance of steel building on shake table using multi input multi output models

3―1 Assessment of Structural Performance of Steel Building on Shake Table Using Multi Input Multi Output Models Academic Year 2010 Ho Thu Hien Master’ ster ’s Thesis Academic Year Year 2010 2010 Keio University Graduate School of Science and Technology School of Science for Open and Environmental Systems Systems As we know, earthquakes have caused many serious damages; that is why it is needed to study the health of buildings after these earthquakes After a large earthquake, evaluation of damage of structures is an important task for health assessment Vibrations of buildings give us valuable information on it Changes in the modal properties like natural frequencies, modal shapes and modal damping are very important to assess the structures Among the representative structural characteristics, natural frequencies provide the global information However they are relatively simple, accurate to measure and easy to obtain Besides, the changes in frequencies must be considered to assess the health of structure When the frequency shifts give the general health assessment, the mode shape changes can be categorized up to the higher level of damage identification – determination of the geometric location of the damage This study will consider the frequencies shifts and their mode shapes with various levels of seismic excitations The excitations are represented by different intensity levels of the 1995 Hyogoken Nanbu Earthquake that are obtained in JR – Takatori Station The acceleration data of E–defense tests on full scale story steel building will be analyzed Five sets of acceleration data were measured at center and corners on shake table and stories of the full scale model were considered as inputs and outputs signals of many types of multi input multi output (MIMO) models From the defined models, some first mode natural frequencies of structure will be obtained and compared to each other By analyzing the two first mode natural frequencies of X and Y directions, the capacity of structure will be assessed with its performance The aim of this research is to assess the capacity of a steel building after a seismic activity using real size shake table tests Course No !" # ! " # $ % &''( - $ $ % ) * *# " +, # $ / / / / 123245 " $ / " $ % 2 92 : 4 2 - 12 : : - ) 2 2 ; 2 2 : < 12 $ * - + ! && & &= &> ? @ & =& &A == */B && => " / $ / ' &= = *% =( , >& &' >= ) =C >> =@ > *% > ! &( % " &C " ! & > = 2324 ( > 2324 C C @ # # $ 67