Earthquake Engineering & Structural Dynamics最新文献

{"title":"Characterization of the Strain Rates in Steel Reinforcement During the Seismic Response of Reinforced Concrete Structures","authors":"Juan F. Velásquez,&nbsp;José I. Restrepo,&nbsp;John J. Blandón,&nbsp;Freddy Bolaños","doi":"10.1002/eqe.4352","DOIUrl":"https://doi.org/10.1002/eqe.4352","url":null,"abstract":"<div>\u0000 \u0000 <p>Predicting the seismic performance of reinforced concrete structures responding nonlinearly during strong-intensity earthquakes is one of the most vexing challenges in structural modeling nowadays. Efforts in nonlinear structural modeling have been made since the 1960s, with the latest models having increased complexity. This paper uses data collected from two reinforced concrete specimens built at full scale and tested in the National Science Foundation-funded single-axis Large High-Performance Outdoor Shake Table of the University of California at San Diego. The strain rates derived from strain gauge readings placed in longitudinal bars undergoing plastic deformations in the plastic hinge regions of these two specimens were derived and characterized. To the authors’ knowledge, this is the first paper that reports and characterizes the strain rates recorded on longitudinal bars in plastic hinge regions of full-scale reinforced concrete specimens subjected to strong input ground motions. Test observations indicate strain rates can be high when the Lüders bands nucleate and traverse the strain gauges. The strain rate in one of the specimens reached 44%/s. Once the Lüders bands had fully developed, strain rates reached nearly 20%/s, which was still significant. Most current computational models developed to assess the seismic response of reinforced concrete structures neglect the strain rate dependency of reinforcing steel. If constitutive stress–strain relationships were made strain rate dependent, the fraction of the empirically prescribed damping in the models could be reduced.</p>\u0000 </div>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"2134-2151"},"PeriodicalIF":4.3,"publicationDate":"2025-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Seismic Meta-Foundations With Imperfect Interfaces","authors":"Anchen Ni,&nbsp;Xingbo Pu,&nbsp;Zhifei Shi,&nbsp;Ioannis Antoniadis","doi":"10.1002/eqe.4357","DOIUrl":"https://doi.org/10.1002/eqe.4357","url":null,"abstract":"<p>Seismic wave isolation through layered meta-foundations is an emerging area of research, driven by its intrinsic theoretical significance and potential practical applications. To date, the complexities associated with imperfect interfaces have often been overlooked in the development of analytical frameworks, which tend to prioritize simple yet effective closed-form dispersion laws. This work provides a further step toward the analytical study of meta-foundations under real-world conditions by incorporating the effects of imperfect interfaces. Our developed framework demonstrates that accounting for interface effects markedly enhances ultra-low-frequency wave attenuation in meta-foundations, as revealed through complex dispersion analysis and verified by transmission analysis of finite-sized meta-foundations. This enhancement is achieved by modifying the stiffness and mass of the interfaces, which affects both the location and width of frequency attenuation zones (AZs) and improves wave attenuation within these frequency domains. Overall, our meta-foundations that incorporate interface effects demonstrate superior performance compared to traditional meta-foundations. This study offers a practical analytical model for meta-foundations and explores the effects of interface imperfections on their dynamic properties, paving the way for further advancements in the design of novel meta-foundations with artificial interfaces.</p>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"2121-2133"},"PeriodicalIF":4.3,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eqe.4357","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944729","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Video Tracking of Targets for Vibration Measurement of Large-Scale Structures Under Seismic Excitation","authors":"Stefania Lo Feudo,&nbsp;Yunhyeok Han,&nbsp;Gwendal Cumunel,&nbsp;Ryan Hoult,&nbsp;Alex Bertholet,&nbsp;Denis Garnier,&nbsp;Paulo Candeias,&nbsp;António A. Correia,&nbsp;João Pacheco de Almeida","doi":"10.1002/eqe.4353","DOIUrl":"https://doi.org/10.1002/eqe.4353","url":null,"abstract":"<div>\u0000 \u0000 <p>Development of video-based vibration techniques and reliability of displacement measurements have important implications in several areas, including structural testing and monitoring of large structures. Through the use of numerous targets placed on the structure, 3-dimensional (3D) analysis, and modal identification can be performed with minimal installation costs, no mass increase, and contactlessly. This study applies and validates video tracking of targets for vibration analysis of a large-scale structure, namely, a reinforced concrete U-shaped wall, tested experimentally under seismic excitation on a shake table. 2D grids of targets are placed on two orthogonal surfaces and filmed by several cameras. Values obtained from a motion capture system, digital image correlation, and traditional displacement sensors are compared. Results confirm that the 3D motion of the U-shaped wall surfaces and foundation can be accurately extracted from video analysis.</p></div>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"2106-2120"},"PeriodicalIF":4.3,"publicationDate":"2025-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944728","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of Soil–Structure Interaction Modeling Simplifications and Structural Nonlinearity on Uncertainty in EDPs: A Case Study on an Existing RC Building in Santiago","authors":"Alberto Hurtado Valdés,&nbsp;Eduardo Torres,&nbsp;Guido Camata,&nbsp;Massimo Petracca,&nbsp;Jorge G. F. Crempien,&nbsp;José A. Abell","doi":"10.1002/eqe.4340","DOIUrl":"https://doi.org/10.1002/eqe.4340","url":null,"abstract":"<div>\u0000 \u0000 <p>This study investigates the impact of modeling simplifications on the uncertainty of seismic response in numerical simulations, focusing on a five-story, asymmetric-plan, reinforced-concrete building in Santiago, Chile, subjected to simulated seismic motions from hypothetical events at the San Ramón fault (SRF). In order to achieve this, a comparative analysis is conducted between a high-complexity reference model and lower-complexity models. The reference model incorporates three-dimensional seismic inputs using the domain reduction method (DRM) and a detailed structural model accounting for material nonlinear behavior. The complexity of the models is systematically reduced to assess the effects of different soil–structure interaction (SSI) modeling assumptions. These assumptions include the use of DRM and plane-wave (PW) input, and also the exclusion of SSI through fixed-base (FB) conditions. For each model, both linear and nonlinear material behaviors are considered. Given the lack of historical records from the SRF, the study employs source-to-structure physical simulation to address seismic performance evaluation as well as its sensitivity to modeling. Simulations are conducted in OpenSees using input motions from 10 realizations of a <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 <msub>\u0000 <mi>M</mi>\u0000 <mi>w</mi>\u0000 </msub>\u0000 <mo>=</mo>\u0000 <mn>6.7</mn>\u0000 </mrow>\u0000 <annotation>$M_w = 6.7$</annotation>\u0000 </semantics></math> event at the SRF, generated with the <span>ShakerMaker</span> Python library. With respect to the reference model, findings indicate that PW assumptions moderately increase uncertainty across different engineering demand parameters (EDPs) and analysis directions. Conversely, FB conditions significantly elevate modeling uncertainty, drastically changing the mean and variance of computed EDPs. A simple EDP sensitivity score is proposed to compare the statistics of computed EDPs, from which a global performance-score is constructed for ranking of models with respect to the reference model. The ranking shows that linear FB models may outperform non-linear FB models, highlighting a complex and nonintuitive relationship between structural nonlinearity and soil flexibility modeling on uncertainty. There are also indications that high-complexity modeling, accounting for the spatio-temporal complexities of the seismic wave-field through the DRM, is needed for responses quantities sensitive to high frequencies. Overall, it is shown that even for this realistic building, located on a very stiff soil, the effects of SSI cannot be neglected as this can produce unpredictable changes in mean and variance of computed EDPs.</p></div>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"2062-2083"},"PeriodicalIF":4.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-Axial Subassemblage Testing System for Hybrid Simulation With Large-Scale Structural Components","authors":"Diego Pizarro,&nbsp;Milan Kovarbašić,&nbsp;Giuseppe Abbiati,&nbsp;Božidar Stojadinović","doi":"10.1002/eqe.4351","DOIUrl":"https://doi.org/10.1002/eqe.4351","url":null,"abstract":"<p>This article presents the Multi-Axial Subassemblage Testing facility of ETH Zurich, Switzerland (ETHZ-MAST) for quasi-static testing and hybrid simulation (HS) of large-scale structural components and assemblies. The ETHZ-MAST features a 6-degrees-of-freedom (DOFs, 3 translations and 3 rotations) loading system based on a steel crosshead and 10 hydraulic actuators. The control system of the test system allows for mixed-mode control of applied boundary conditions meaning that some DOFs can be controlled in force while the remaining are controlled in displacement. The control system relies on a kinematic model of the system and compensates for the elastic deformation of the crosshead and the backlash in the actuator clevises. The capabilities of the facility are demonstrated with two experimental campaigns on reinforced concrete shear walls, which comprise in-plane quasi-static cyclic testing and HS of nominally identical axially loaded specimens. One of the campaigns studied the transition between flexure and rocking behavior modes in specimens with spliced reinforcement, whereas the other addressed the transition between shear and sliding behavior modes. A comparison between the testing protocols revealed that the specimens tested in HS using a ground motion excitation had a larger displacement capacity than the nominally identical specimens tested using a quasi-static cycling test protocol. However, the behavior mode transitions the specimens exhibited did not depend on the test protocol, but on the specimen strengths and the applied axial loads.</p>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"2084-2105"},"PeriodicalIF":4.3,"publicationDate":"2025-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eqe.4351","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Risk-Based Structural Seismic Response Assessment of Large-Scale Jacket-Supported Offshore Wind Turbines","authors":"Zeyad Khalil,&nbsp;Peter J. Stafford,&nbsp;Ahmed Y. Elghazouli","doi":"10.1002/eqe.4348","DOIUrl":"https://doi.org/10.1002/eqe.4348","url":null,"abstract":"<p>Offshore wind energy is growing as a major contributor to achieving the current targets of reaching net-zero carbon emissions globally, offering a scalable, reliable, and cost-competitive energy source. With the worldwide momentum of investing in wind energy infrastructure, offshore wind farms are now being constructed in seismically active regions, along with ambitious future expansion plans in countries of moderate-to-high seismic activity. To date, limited data exists on the long-term performance of large-scale offshore wind turbines under earthquake loading, which necessitates a comprehensive understanding of the performance of such assets under moderate and extreme seismic events. This study provides a risk-based assessment of the seismic performance of jacket-supported offshore turbines which have received less attention in the literature compared to monopile-supported offshore turbines, and can provide a more attractive solution in seismic regions. The performance of a four-legged, X-braced reference jacket structure supporting a 10 MW turbine located in a reference site of high seismicity, where different source types drive the seismic hazard, is investigated using response history analysis. Particular emphasis is given to the hazard-consistent ground-motion selection methodology required for properly evaluating the response considering several seismic response measures. To achieve this, 300 nonlinear response history analyses are conducted to investigate the maximum acceleration and drift demands at the rotor-nacelle assembly (RNA) level across a range of seismic hazard intensity levels. Additionally, conditional fragility curves for different acceleration and drift limits and demand curves showing the annual rate of exceedance as a function of demand values are reported. The study highlights the high sensitivity of the obtained results to the demand limit definition for both drifts and accelerations at the RNA level. This emphasizes the need for proper and consistent definitions of demand limits and acceptance criteria to provide reliable risk-based damage and loss assessments.</p>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"2044-2061"},"PeriodicalIF":4.3,"publicationDate":"2025-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eqe.4348","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Investigation of an Earthquake-Resistant Steel Bridge Substructure System","authors":"Arjun Jayaprakash,&nbsp;Mervyn Kowalsky,&nbsp;James Nau","doi":"10.1002/eqe.4344","DOIUrl":"https://doi.org/10.1002/eqe.4344","url":null,"abstract":"<p>The grouted shear stud connection has been experimentally shown to provide two-column steel bridge bent systems with seismic resistance. It achieves this by relocating the plastic hinging to the column section, thereby mobilizing the full strength and ductility of the steel columns. However, to be able to carry out displacement-based design procedure, accurate estimation of system displacements is necessary and no such models currently exist for these substructure systems. In this study, a fiber-based numerical model and an approximate hand calculation model are developed that can estimate the full force–displacement response of these systems. These models were developed by first carrying out cyclic pushover experiments on large-scale two-column bridge bent specimens and subsequently calibrating numerical models, which were able to simulate experimental structural response.</p>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"2009-2030"},"PeriodicalIF":4.3,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eqe.4344","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep Learning-Based Response Spectrum Analysis Method for Bridges Subjected to Bi-Directional Ground Motions","authors":"Taeyong Kim,&nbsp;Oh-Sung Kwon,&nbsp;Junho Song","doi":"10.1002/eqe.4345","DOIUrl":"https://doi.org/10.1002/eqe.4345","url":null,"abstract":"<p>The response spectrum analysis method is one of the most widely used approaches developed to estimate the seismic demands of structural systems with minimal computational expense while maintaining high accuracy. The authors recently proposed a deep learning-based combination (DC) rule to enhance the prediction accuracy of the response spectrum analysis method without compromising computational efficiency. The DC rule employs a deep neural network (DNN) model to estimate the contributions of individual modal responses. The DC rule, primarily developed for building structural systems, has limitations in its applications to bridge structures, particularly those subjected to bi-directional ground motions. Moreover, the inherent “black box” nature of deep learning models restricts the interpretability and practicality of the method. To address these challenges, this research further develops the DC rule in three aspects. First, we construct a seismic demand database for bridge structures subjected to bi-directional ground motions. Second, the DC rule is extended to accommodate structural systems under bi-directional ground motion excitations. Third, we develop a simplified regression-based model to replace the DNN model, thereby enhancing the practicality and interpretability of the DC rule approach. Extensive numerical investigations are conducted to validate the performance of the proposed framework, demonstrating its efficiency and accuracy in predicting the seismic demands of bridge structures. The source codes, data, and trained DNN models are available for download at https://github.com/TyongKim/ERD2.</p>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"2031-2043"},"PeriodicalIF":4.3,"publicationDate":"2025-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/eqe.4345","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945004","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Variability in Damping Ratios on the Seismic Risk of Steel Moment-Frame Buildings","authors":"Alvaro Aravena,&nbsp;Cristian Cruz","doi":"10.1002/eqe.4349","DOIUrl":"https://doi.org/10.1002/eqe.4349","url":null,"abstract":"<div>\u0000 \u0000 <p>This paper evaluates the sensitivity of seismic risk to variations in damping ratio in four steel moment-frame buildings of 4, 9, 20, and 50 stories. Seismic risk is quantified through the expected annual loss (EAL) due to earthquake ground motions. Nonlinear models of the buildings are developed using OpenSees, where damping ratios are systematically altered within defined ranges. The influence of damping ratio on collapse fragility and EAL deaggregation is assessed using PEER's framework for performance-based earthquake engineering, considering the contribution from structural and nonstructural elements, as well as contents. Results show that when the damping ratio is varied within two standard deviations from its median value based on height, the probability of collapse of the buildings when subjected to the maximum considered earthquake varies between −60% and +35%. This same range of damping ratio generates a variation of up to approximately ±35% in the EAL of the buildings. It is found that EAL deaggregation is highly sensitive to the damping ratio at low intensities, where nonstructural components dominate economic losses. The study establishes a moderate effect on deaggregation at intensities where demolition costs contribute significantly to EAL. Conversely, at large intensities, where collapse governs the EAL, deaggregation becomes insensitive to changes in the damping ratio. Finally, the impact of damping models on EAL is explored, demonstrating differences of up to 10% when employing modal damping versus various variations of Rayleigh damping in the 50-story building.</p>\u0000 </div>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"1992-2008"},"PeriodicalIF":4.3,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944525","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of the Hypocenter Location of a Mw7.0 Scenario Earthquake on the Hayward Fault on the Seismic Response of Tall Buildings in San Francisco","authors":"James Bantis,&nbsp;Eduardo Miranda,&nbsp;Pablo Heresi","doi":"10.1002/eqe.4339","DOIUrl":"https://doi.org/10.1002/eqe.4339","url":null,"abstract":"<div>\u0000 \u0000 <p>A regional seismic risk assessment of the tallest 150 buildings in the Financial District of the city of San Francisco, California is conducted when subjected to three hypothetical M_w7.0 earthquakes on the Hayward Fault with different hypocenters, but rupturing the same area, situated to the north, east, and south of the Financial District. The analyses are conducted using a probabilistic Monte Carlo-based framework previously proposed by the authors, which uses reduced-order models with linear-elastic analyses to perform simplified site-response analyses at each site and compute responses of each building in both principal orientations. The combined effect of the hypocenter location and building orientation on the hazard and building responses is carefully analyzed. Results indicate that peak building inter-story drift ratios may change by as much as 20% with a change in the hypocenter location along the Hayward Fault, suggesting that regional seismic risk assessments for a scenario earthquake should consider multiple hypocenter locations for a given rupture area. Furthermore, peak building inter-story drift ratios can change by as much as 34% with a change in both the hypocenter location along the Hayward Fault and the building principal orientation. Building inter-story drift ratios at different building heights (i.e., not just where inter-story drift ratios are maximum) can also change by much more than 34% with a change in the hypocenter location. This study also compares the hazard and building responses computed with the proposed framework to those computed with a commonly used Ground Motion Model (GMM). Results show that current GMMs overestimate response spectral ordinates for longer periods of vibration at shallow, soft-soil sites, consequently leading to overestimations in displacement-based responses of tall buildings.</p>\u0000 </div>","PeriodicalId":11390,"journal":{"name":"Earthquake Engineering & Structural Dynamics","volume":"54 8","pages":"1975-1991"},"PeriodicalIF":4.3,"publicationDate":"2025-03-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143944524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}