Hysteretic models that incorporate strength and stiffness deterioration

TLDR

The study introduces, calibrates, and applies simple hysteretic models that incorporate strength and stiffness deterioration to improve demand predictions as a structural system nears collapse. Three standard hysteretic models—bilinear, peak‑oriented, and pinching—are modified to include deterioration via an energy‑based parameter that governs four cyclic modes (basic strength, post‑capping strength, unloading stiffness, accelerated reloading stiffness) and accounts for post‑yield softening and residual strength. Calibration on steel, plywood, and reinforced‑concrete components confirms the models capture key deterioration behaviors, and their use in a peak‑oriented SDOF seismic evaluation demonstrates advantages for highly inelastic systems. © 2005 John Wiley & Sons, Ltd.

Abstract

This paper presents the description, calibration and application of relatively simple hysteretic models that include strength and stiffness deterioration properties, features that are critical for demand predictions as a structural system approaches collapse. Three of the basic hysteretic models used in seismic demand evaluation are modified to include deterioration properties: bilinear, peak-oriented, and pinching. The modified models include most of the sources of deterioration: i.e. various modes of cyclic deterioration and softening of the post-yielding stiffness, and also account for a residual strength after deterioration. The models incorporate an energy-based deterioration parameter that controls four cyclic deterioration modes: basic strength, post-capping strength, unloading stiffness, and accelerated reloading stiffness deterioration. Calibration of the hysteretic models on steel, plywood, and reinforced-concrete components demonstrates that the proposed models are capable of simulating the main characteristics that influence deterioration. An application of a peak-oriented deterioration model in the seismic evaluation of single-degree-of-freedom (SDOF) systems is illustrated. The advantages of using deteriorating hysteretic models for obtaining the response of highly inelastic systems are discussed. Copyright © 2005 John Wiley & Sons, Ltd.