Seismic Performance Evaluation Of High-rise Buildings Based On The Local And Global Monitoring Information

With the rapid development of economy and urbanization, a large number of high-rise buildings were being built in our country. Meanwhile, occurrence of earthquakes is always accompanied with severe disasters, especially in populated mega cities where the vast majority of high-rise buildings were located. So the evaluation of the degree of structural damage becomes significant for a better understanding of the structural seismic performance. So far, some research scholars are keen on making the structural health monitoring system applied in the high-rise buildings. In order to forecast the seismic performance of structures, the structures are being monitored all the time.With reference and further research to the optimal placement of the sensor, the structural initial modal vector matrices are suggested to be reconsidered. The modal vectors are combined to form modal vector matrix on the premise that at least certain number modes remained. At the same time, the relation between the structural damage index and the optimized resulted of the modal vector matrix is established. The research shows that comparing to those damage indexes based on the inter-story drift, the detrimental inter-story drift and the inter-story pure translation, the damage index based on the modal information is more suitable for the damage analysis of high-rise building. The index can be more in line with the actual damage of the structure and be more beneficial to predict the structural seismic damage condition.This paper presents a revised weighted combination method, in which the weighting coefficient is expressed as a linear combination of the existed static coefficient and the static coefficient based on responsive information. Under earthquake especially strong earthquake, response-based interpretation about structural damage evolution is quite necessary. Specifically, by comparing with the structural global damage index based on the revised Ghobarah model, the proposed weighting coefficient could not only reflect the weaker part of the structure, but also evaluate degrees of the whole structural damage. It is suggested that, the parameter a’is supposed to be constant value and the parameter β’has been shown to be positively related with PGA. If the level of PGA is relatively low, the damage outputs from different weighting coefficients are similar. As PGA level increases, the proposed weighting coefficients could yield more reasonable damage predictions. The modified weighted combination method with the proposed weighting coefficients is proved to be applicable for assessing damage of frame structures under earthquakes. An example given in the end of this paper is helpful for understanding how to apply the research results.