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Free Webinar: FEMA P-2139, Short-Period Building Collapse Performance and Recommendations for Improving Seismic Design 26 April 2022 منبع مشاهده فیلم وبینار دانلود فیلم

Investigation of March 15, 2018 Pedestrian Bridge Collapse at Florida International University, Miami, Fl June 2019 @civilbest - Miami FIU Bridge Collapse 2018 - Report.pdf

Collapse Assessment of RC Structures فیلم آموزشی به زبان اصلی در حدود 18 دقیقه مربوط به یک ورکشاپ آموزشی منبع Collapse Assessment of RC Structures.mp4

Hysteretic models that incorporate strength and stiffness deterioration Luis F. Ibarra1;∗; †; ‡, Ricardo A. Medina2 and Helmut Krawinkler3 1Southwest Research Institute; CNWRA; San Antonio; TX 78238; U.S.A. 2Department of Civil and Environmental Engineering; University of Maryland; College Park; MD 20742; U.S.A. 3Department of Civil and Environmental Engineering; Stanford University; Palo Alto; CA 94305; U.S.A. SUMMARY This paper presents the description, calibration and application of relatively simple hysteretic models that include strength and stiness 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 modied to include deterioration properties: bilinear, peak-oriented, and pinching. The modied models include most of the sources of deterioration: i.e. various modes of cyclic deterioration and softening of the post-yielding stiness, 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 stiness, and accelerated reloading stiness 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 inuence 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. KEY WORDS: hysteretic behaviour; strength deterioration; cyclic deterioration; collapse منبع دانلود از پیوست HEERAD.IR-Ibarra Medina Krawinkler.pdf

Global collapse of frame structures under seismic excitations Lf Ibarra, H Krawinkler Submitted to the Department of Civil and Environmental Engineering. Copyright by the author. Thesis (Ph. D.)--Stanford University, 2004. Global collapse in earthquake engineering refers to the inability of a structural system to sustain gravity loads when subjected to seismic excitation. This research proposes a methodology for evaluating global incremental (side-sway) collapse based on a relative intensity measure instead of an engineering demand parameter. The report presents applications of the proposed collapse methodology to the development of collapse fragility curves and the evaluation of the mean annual frequency of collapse. [Hidden Content] TR152_Ibarra.pdf

Probabilistic Response Evaluation of Plan-Irregular Buildings Subjected to Bi-directional Seismic Loading Original Article, D34 Manie S, Moghadam AS, Ghafory-Ashtiany M. J. Civil Eng. Urban. 4(3): 223-232. 2014 ABSTRACT: The present paper aim at evaluating the response of three-dimensional buildings with in-plan unidirectional mass irregularities subjected to bi-directional seismic loading. The study is carried out in a probabilistic frame-work considering the response of the structural models at their near-collapse nonlinear state of response. To this end, three-dimensional 3 and 6-story reinforced concrete building structures with unidirectional mass eccentricities equal to 0% (symmetrical), 10%, 20% and 30%, were subjected to extensive nonlinear incremental dynamic analyses (IDA) utilizing degrading hysteretic models under a set of far-field two-component ground motions records. The collapse-level intensities of each model under all records were, then, assessed using standard uni-variate as well as bi-variate statistical and probabilistic analysis procedures. Results demonstrated that remarkable differences exist between behavior of regular and irregular buildings in terms of median collapse-level spectral intensities, the corresponding coefficients of variation, and the properties of the associated probability density and cumulative density functions (PDFs and CDFs). The paper, also, introduces the “fragility surface” concept as an alternative to conventional fragility curves for collapse behavior assessment of three-dimensional structures. Keywords: Torsional Buildings, Probabilistic, Collapse, Plan Irregularity, Low-Rise Buildings. منبع: [Hidden Content] دانلود: [Hidden Content].,%204%20(3)%20223-232,%202014.pdf J. Civil Eng. Urban., 4 (3) 223-232, 2014.pdf