Seismic behavior of highly irregular structures with multiple passive energy dissipation system: Case study of a single‐column elevated station

Abstract

Summary This paper presents a case study of the layout strategy for a multiple passive energy dissipation (MPED) system and its influence on the seismic behavior of highly irregular structures. The investigated structure is a single‐column elevated station in a cantilevered structure form, which is unique and characterized by uneven mass and stiffness distributions in both elevation and plane. To improve seismic resistances of the focused structure, the MPED system composed of multiple types of passive energy dissipation (PED) devices targeting different vulnerabilities is devised. In addition, a high‐fidelity and efficient numerical model is developed to assess the structural seismic performance, by leveraging the secondary development based on proprietary finite‐element analysis package MARC.MSC. The fiber beam–column elements are employed to simulate the composite members under complex loading conditions, and spring elements incorporated with cyclic hardening property are developed to simulate the PED devices. Nonlinear static and time history analysis are conducted for the key substructures and whole structure. The results demonstrate that the MPED system can effectively improve the stiffness, strength, and ductility of the structure and significantly reduce its global responses. A comprehensive evaluation indicates that the MPED system is beneficial for the members directly equipped with PED devices, but the benefits are limited for unprotected members that require special attentions in design to avoid secondary damage. Through this study, valid analysis tools and suggestions are provided for the design of high‐irregular structures with MPED system.

Seismic Assessment of a Single-Column Elevated Station Structure

“…The three sub-indices were averaged to obtain the index of the overall structure. The sub-index of the translation in the X direction, Er(X), can be calculated using Equation (8), where X i,BPA/NRHA denotes the displacement in the X direction at the mass center of the i th floor of the structure using the BPA or NRHA method. Similarly, the sub-index of the translation in the Y direction, Er(Y), can be calculated using Equation (9).…”

“…The composite structure system can effectively reduce the component size and realize multiple failure mechanisms in the vertical and horizontal directions, improving the seismic performance of complex station systems. Zhuang et al [8] applied multiple passive energy dissipation (MPED) devices to the vulnerable parts of the structure to improve its seismic performance. Nonlinear static and time-history analyses of the key substructure and entire structure revealed that the MPED system could effectively enhance the strength, stiffness, and ductility of the structure, reduce the general response significantly, and increase the energy dissipation capacity of the overall structure.…”