Balancing the Beneficial Contributions of Foundation Rocking and Structural Yielding to Improve Structural Seismic Resilience

Liu, W.; Hutchinson, Tara C.; Kutter, Bruce L.; Hakhamaneshi, Manouchehr; Gavras, A-G.

doi:10.7712/120113.4710.c1408

Cited by 7 publications

(8 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It is important to note that the relative amount of dissipated energy of the footings and structural fuses are quite comparable between the asymmetric models (dashed lines) and the symmetric models (solid lines). This consistency applies to the BD system as well . As such, it is concluded that the building asymmetry, which results in relatively pronounced axial load fluctuation did not significantly alter the distribution of energy dissipation in this system, regardless of the motion intensity and the yielding hierarchy between the dominant inelastic elements.…”

Section: Seismic Response Comparison Between Asymmetric and Symmetricmentioning

confidence: 57%

“…These plots show that all symmetric models accumulate less permanent deformation than their asymmetric counterparts, particularly for the FRD model. Although not shown, it is noted that the symmetric BD model experienced less residual deformation than its asymmetric counterpart as well . In addition, all asymmetric models cumulate a negative residual deformation, in other words ratcheting towards their weak direction.…”

Section: Seismic Response Comparison Between Asymmetric and Symmetricmentioning

confidence: 87%

“…The response of the aFRD and sFRD models under quasi‐static cyclic loading is compared in this section. Although these tests were carried out after the sequential dynamic shaking, physical observations after the sequential dynamic shaking indicate that the structural components and surrounding soil of both models were not severely damaged or deformed . Therefore, the post‐dynamic quasi‐static cyclic testing is a reasonable means to characterize the model's seismic performance.…”

Section: Cyclic Response Of the Afrd And Sfrd Modelsmentioning

confidence: 99%

See 2 more Smart Citations

Effect of earthquake‐induced axial load fluctuations on asymmetric frame–wall–rocking foundation systems

Liu

Hutchinson

Kutter

et al. 2015

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

SUMMARYFluctuations in axial load imposed on a rocking footing will affect its moment capacity, the shape of its moment-rotation hysteresis, and potentially the system's seismic performance. Structural asymmetry increases the likelihood of axial load variation during earthquake excitations. To investigate this issue, a unique centrifuge testing program was carried out on low-rise frame-wall-rocking foundation systems. In this paper, the seismic behaviors of asymmetric and symmetric models from this test program are systematically compared. Experimental results reveal that placing the lateral force resisting shear wall outboard produces significant axial load fluctuation, which in turn greatly deteriorate the lateral load-carrying capacity of a foundation rocking dominated frame-wall system, particularly in its weak direction. However, it strengthens the system when loading is towards the shear wall, leading to a highly asymmetric hysteretic response. During earthquake loading, all asymmetric rocking foundation systems observe smaller peak roof accelerations, but larger peak and permanent roof drifts compared with the symmetric systems. Despite these differences in response, the axial load fluctuation and structural asymmetry do not significantly change the relative energy dissipated by the rocking foundations and inelastic structural components within each framewall-rocking foundation model. Copyright © 2015 John Wiley & Sons, Ltd. KEY WORDS: axial load fluctuation; frame-wall structure; foundation rocking; asymmetry; nonlinear soilstructure interaction; seismic testing; centrifuge modeling 1. BACKGROUND AND RESEARCH SCOPE BackgroundArchitectural aesthetics or building functionality often leads to requirements for large open bays in buildings. Structural shear walls, however, are highly successful at minimizing interstory drift demands induced by an earthquake. Many buildings require a compromise between these two competing design issues and therefore are constructed of mixed systems, i.e. walls and frames, with multiple load resisting systems. As a result, it is not uncommon that the building load path becomes asymmetric. When subjected to lateral wind or seismic load, building asymmetry could produce a coupled response between its lateral and torsional modes, which greatly complicates the analysis of the system. Researchers have realized this issue and proposed approximate analytic solutions [e.g. 1, 2], or developed simplified numerical methods for estimating the seismic demand to these structures [e.g. 3-5]. These and other studies highlight another key aspect of the asymmetry, namely that axial

show abstract

Section: Seismic Response Comparison Between Asymmetric and Symmetricmentioning

confidence: 57%

Section: Seismic Response Comparison Between Asymmetric and Symmetricmentioning

confidence: 87%

Section: Cyclic Response Of the Afrd And Sfrd Modelsmentioning

confidence: 99%

See 1 more Smart Citation

Effect of earthquake‐induced axial load fluctuations on asymmetric frame–wall–rocking foundation systems

Liu

Hutchinson

Kutter

et al. 2015

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

show abstract

“…For example, at large κ f values ( κ f ≥ 0.9) and at high ductility values ( μ ≥ 6.0) the hysteresis can support Zone 2 type behavior. Additional investigations of the effects of κ d and β are provided in Liu (2014).…”

Section: Stiffness Degrading and Pinching (Sdp) Systemmentioning

confidence: 99%

Characterizing Seismic Resiliency Using an Energy Dissipation-Recentering Correlation Diagram

Liu¹,

Hutchinson

2016

Earthquake Spectra

View full text Add to dashboard Cite

For a structural system, the potential to dissipate energy and re-center during an earthquake are two important characteristics, which support seismic resiliency. This paper proposes two dimensionless parameters, namely an energy dissipation ratio (RED) and a re-centering ratio (RRC), to quantify the potential of an inelastic mechanism to dissipate hysteretic energy and recover from inelastic deformations, respectively.For most mechanisms used in seismic design, these two parameters are not independent, but rather they are inherently related. In this work, an RED-RRC correlation diagram is established by placing each parameter within a 2-dimensional plot.Importantly, four different zones with varying seismic response attributes are identified. Numerical studies considering various idealized inelastic systems coupled with experimental data are then utilized to demonstrate the utility of the RED-RRC correlation diagram as a simple design tool for estimating the seismic resiliency of a system. BACKGROUND AND MOTIVATION

show abstract

“…Studies of Hakhamaneshi (2014) and Hakhamaneshi and Kutter (2016) aimed to evaluate the performance of rocking foundations with different shapes and embedment depths and revealed the larger settlements in narrower rectangular and I-shaped footings. Liu et al (2013) and Liu (2014) investigated the performance of low-rise frames and observed the beneficial features of balancing the foundation rocking and structural inelasticity. Aiming to support the concept of controlled share of ductility demand between superstructure and foundation, Pecker et al (2014) provided an overview of the experimental activities for seismic evaluation of nonlinear foundations and theoretical achievements in using foundation macro-element models in DBD framework.…”

Section: Introductionmentioning

confidence: 99%

Empirical Models to Formulate the Nonlinear Response of Rocking Shallow Foundations

Hamidpour

Shakib

Paolucci

et al. 2021

Preprint

View full text Add to dashboard Cite

This paper aims to introduce a simplified moment-rotation backbone model for exploring the nonlinear behavior of shallow foundations subjected to rocking. The model is developed based on parametric numerical investigations of rectangular footings on dense dry sand, taking advantage of a nonlinear macro-element model verified based on a set of experimental results. Empirical expressions are proposed for rocking stiffness degradation due to gravity loads and foundation rotation as a function of the factor of safety against vertical loads and aspect ratio of foundations. Similar to previous researches, the uplift reference rotation was introduced to explore a new closedform expression appropriate for normalizing the foundation response in a non-dimensional form. The proposed approach for stiffness degradation and nonlinear backbone model of rocking foundations aims to be simple, to minimize the dependence on the variable parameters, and to provide physically sound selections for engineering applications.

show abstract

Balancing the Beneficial Contributions of Foundation Rocking and Structural Yielding to Improve Structural Seismic Resilience

Abstract: Abstract. To date, numerous individual and system-level experimental studies have illustrat-

Cited by 7 publications

References 13 publications

Effect of earthquake‐induced axial load fluctuations on asymmetric frame–wall–rocking foundation systems

Effect of earthquake‐induced axial load fluctuations on asymmetric frame–wall–rocking foundation systems

Characterizing Seismic Resiliency Using an Energy Dissipation-Recentering Correlation Diagram

Empirical Models to Formulate the Nonlinear Response of Rocking Shallow Foundations

Contact Info

Product

Resources

About