Advancements in Pushover Analysis for Improved Seismic Performance Evaluation
摘要
The pushover method is a simplified yet effective seismic analysis tool that estimates the nonlinear behavior of structures under increasing lateral loads, commonly used in performance-based earthquake engineering. This review discusses the development, applications, and advancements in both monotonic and cyclic pushover methods, which are essential tools in seismic analysis. Monotonic pushover methods, which include non-adaptive approaches such as the Capacity Spectrum Method and N2 method, are widely used for their simplicity and practicality, particularly in low- to mid-rise buildings. However, these methods fail to account for higher-mode effects and complex structural behavior, especially in taller or irregular structures. To address these limitations, adaptive methods have been developed to improve accuracy by adjusting the lateral load distribution and accounting for changes in stiffness and dynamic properties as the structure deforms. These methods show better correlation with nonlinear time-history analysis, the gold standard in seismic assessment. On the other hand, the cyclic pushover method has been introduced to consider the dynamic cyclic loading and address stiffness and strength degradation of structural components–factors often overlooked by monotonic methods. Despite its advantages, the pushover method has limitations, and it should not be over-relied upon, as it may provide rapid but superficial predictions of structural behavior. However, its application in risk-based and loss assessment frameworks has expanded its potential for future use. This review highlights the versatility of pushover methods in seismic design and retrofitting, emphasizing their evolving role in improving the accuracy and reliability of structural assessments, contributing to safer and more resilient buildings in earthquake-prone regions.