Seismic Fragility Assessment of Ordinary RC Shear Walls Designed with a Nonlinear Dynamic Analysis

The seismic performance of ordinary reinforced concrete shear walls, that are commonly used in high-rise residential buildings in Korea (h < 60 m), but are prohibited for tall buildings (h ≥ 60 m), is evaluated in this research project within the framework of collapse probability. Three bidimensional analytical models comprised of both coupled and uncoupled shear walls exceeding 60 m in height were designed using nonlinear dynamic analysis in accordance with Korean performance-based seismic design guidelines. Seismic design based on nonlinear dynamic analysis was performed using different shear force amplification factors in order to determine an appropriate factor. Then, an incremental dynamic analysis was performed to evaluate collapse fragility in accordance with the (Federal Emergency Management Agency) FEMA P695 procedure. Four engineering demand parameters including inter-story drift, plastic hinge rotation angle, concrete compressive strain and shear force were introduced to investigate the collapse probability of the designed analytical models. For all analytical models, flexural failure was the primary failure mode but shear force amplification factors played an important role in order to meet the requirement on collapse probability. High-rise ordinary reinforced concrete shear walls designed using seven pairs of ground motion components and a shear force amplification factor ≥ 1.2 were adequate to satisfy the criteria on collapse probability and the collapse margin ratio prescribed in FEMA P695.

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Assessment of the Seismic Response of CLT Shear Walls Using the EEGBW, a Bouc–Wen Class Predictive Model

Infrastructures ◽

10.3390/infrastructures6040055 ◽

2021 ◽

Vol 6 (4) ◽

pp. 55

Author(s):

Angelo Aloisio ◽

Massimo Fragiacomo

Keyword(s):

Dynamic Analysis ◽

Nonlinear Dynamic ◽

Nonlinear Dynamic Analysis ◽

Shear Walls ◽

Numerical Data ◽

Seismic Excitation ◽

Quadratic Error ◽

Cyclic Response ◽

The Stability ◽

Energy Dependent

The paper presents an application of the Extended Energy-dependent Generalized Bouc–Wen model (EEGBW) to simulate the experimental cyclic response of Cross-Laminated Timber (CLT) panels. The main objectives of the paper are assessing the sensitivity of the quadratic error between experimental and numerical data to the EEGBW parameters, showing the fitting performance of the EEGBW model in matching the experimental cyclic response of CLT panels, highlighting the stability of the model in nonlinear dynamic analysis with seismic excitation. The research proves that the considered Bouc–Wen class hysteresis model can reproduce the hysteretic response of structural arrangements characterized by pinching and degradation phenomena. The model exhibits significant stability in nonlinear dynamic analysis with seismic excitation. The model’s stability and versatility endorse its application to simulate structural systems’ dynamic response when Finite Element modelling might be an impractical choice.

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