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Loading Protocols for ASCE 41 Backbone Curves



Bruce F. Maison, Matthew Speicher


ASCE 41-13 is an industry standard for seismic evaluation and retrofit of existing buildings. Alternative component modeling and acceptance criteria are based on a backbone curve constructed from an envelope of component hysteresis loops derived via experimental cyclic tests. ASCE 41-13 requires use of loading protocols having fully-reversed cyclic loadings with increasing displacement levels. However, recent research summarized herein indicates the need for inclusion of different protocols that pay specific attention to behavior close to collapse. This view is given support by example building computer earthquake response simulations described herein. A generalized loading pattern derived from the simulations found relatively few drift excursions having one-direction bias suggesting one-sided cyclic and/or monotonic tests may be better for describing building inelastic seismic demands.
Earthquake Spectra


ASCE 41, backbone curves, loading protocol, seismic, nonlinear modeling


Maison, B. and Speicher, M. (2016), Loading Protocols for ASCE 41 Backbone Curves, Earthquake Spectra, [online], (Accessed June 17, 2024)


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Created October 31, 2016, Updated October 12, 2021