Structural reliability and seismic performance of reinforced concrete building in the performance-based design

In the current seismic building design, there is great necessity of developing a better method for assessing the seismic vulnerability of a structure. An important step towards reaching these goals is to define an adequate measure of building performance with global and local response parameters. A pioneering work for this has been done in the FEMA 273 and VISION 2000 Guidelines and this concept is called the Performance-Based Design. In the Performance-Based Design, overall building performance during an earthquake is measured by the roof drift or inter-story drift. However, an adequate method of building performance evaluation should be capable of representing various types of structural local and global damages. For these reasons, there is a renewed interest in the damage analysis in the current performance-based design.; This study focuses on the nonlinear responses of reinforced concrete building and their seismic performances. Both the structural micro model and the structural macro model are chosen for this study. In the structural micro models, sensitivities between input and response parameters are studied. Nonlinear behaviors in different types of substructures are also observed. Structural macro models are designed by 1997 Uniform Building Code varying the design base shear values. Nonlinear time history analyses are performed using the selected ensemble of earthquake ground motions. The statistical results produce the probabilistic distribution of each response parameters. Correlation relationships among those response parameters are studied and the sensitivities of the response parameters to the different base shear models are observed. Utilizing the results learned from the structural micro and macro model, this study introduces a performance parameter that is called System Damage Index (SDI). The System Damage Index is calibrated with the roof drift or inter-story values at each performance level specified in the recent Guidelines. Probabilistic distribution of the SDI is calculated and the probability of failure at the performance levels is studied. Correlation relationship between the SDI and other global response parameters are also examined.