International Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166927120250101Numerical Investigation of the Influence of Seismic Excitation Characteristics on the Response of Hunchbacked Block-Type Quay Walls with Varying Geometries12171638810.48303/jsee.2024.2039374.1121ENAli AkabrEhteramiPh.D. Candidate, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University (SBU), Tehran, Iran0000-0002-5126-9240BabakEbrahimianAssistant Professor, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University (SBU), Tehran, Iran0000-0001-9196-5374AliNoorzadProfessor, Faculty of Civil, Water and Environmental Engineering, Shahid Beheshti University (SBU), Tehran, Iran0000-0002-3785-7679Journal Article20240823Using the finite element method, this study investigates the seismic behavior of hunchbacked block-type gravity quay walls with varying configurations. The research employs adaptive meshing strategies and error-based adaptivity techniques to refine the plane strain FE meshes. Interface elements are utilized to simulate discontinuities along the wall height, particularly between concrete blocks, and to model the interaction between the quay wall and the adjacent soil medium. The developed FE models are validated against data from 1g shaking table tests available in the literature. The study evaluates the seismic performance of three quay wall models, each with a unique configuration, under a range of seismic loads, including peak ground accelerations from 0.1g to 0.9g and frequencies from 3.0 Hz to 9.0 Hz. The findings indicate that increasing hunch height and optimizing the upper inclination angle effectively reduce lateral earth pressures and horizontal<br>displacements, enhancing seismic performance. The study recommends positioning critical structures, infrastructure, and sensitive buildings in the backfill area at a distance greater than the wall height, as maximum backfill settlement occurs between 0.55H and 0.65H from the quay wall, where significant settlement poses risks to facilities. Additionally, acceleration amplification in the backfill decreases at distances greater than the wall height, indicating reduced seismic impact.https://www.jsee.ir/article_716388_e44bb8319c3b61f9452adb9437e6d3ab.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166927120250101On the Implications of NPD Process Management on DRR Solutions Management233471521710.48303/jsee.2024.2035414.1112ENPouyaSarvghad MoghadamLecturer in Operations Management, Business, School of Management, Swansea University, Swansea, UKNickL. RichProfessor in Operations Management, Business, School of Management, Swansea University, Swansea, UKAbdolreza S.MoghaddamAssociate Professor, Structural Engineering Research Center, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, IranSaraNaghaviResearch assistant, International Institute of Earthquake Engineering and Seismology, IIEES, Tehran, IranJournal Article20240713The ability to compress time and enhance process quality are key determinants of effective New Product Development (NPD) and equally<br>Disaster Risk Reduction (DRR) management. This paper explores the qualitative relevence of an Analytical Hierarchy Process (AHP) derived<br>unified conceptual model of correlation coefficients between NPD subfactors of success and performance measures drawn from dominant<br>classical NPD models. The paper shows the application of the conceptual model to compare base isolation with damper technologies that are amongst the most advanced earthquake risk reduction strategies. The study finds that there are significant benefits for successful knowledge transfer between NPD and civil engineering and earthquake resilience engineering sectors, and there are many potential academic and professional benefits from doing so.https://www.jsee.ir/article_715217_102e1da9281e0b32f9b431ce48529bea.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166927120250101A New Variable Step Size Adaptive Blind Sources Separation for Online Structural Modal Identification354771511510.48303/jsee.2024.2035560.1113ENVidaGhasemiPh.D., School of Civil Engineering, Iran University of Science and Technology, Tehran, IranFereidounAminiProfessor, School of Civil Engineering, Iran University of Science and Technology, Tehran, IranJournal Article20240714The Equivariant adaptive separation by independence (EASI) algorithm, as an online blind structural identification method, is very important not only to better understand the structural response but also to conduct an efficient maintenance and management strategy. However, the traditional EASI algorithm has some drawbacks. It uses a constant step-size parameter and requires establishing a trade-off between the misadjustment in the steady-state and the convergence rate. This paper proposes a new variable step-size equivariant adaptive source separation via independence (VS-EASI) algorithm for online blind modal identification of structures. Unlike the traditional EASI algorithm,<br>the proposed algorithm adaptively updates its step-size based on the input signals and the unmixing matrix, through establishing a new function between the step-size and the separating indicator. This results in a better performance for the proposed method, and fast convergence speed is achieved while the steady-state error is low. Furthermore, this algorithm mitigates the irrelevant noise, making it more suitable than the EASI algorithm for practical applications. Simulation results of synthetic examples and a benchmark structure verify the superior convergence and better performance of the proposed algorithm in the steady-state over the conventional EASI with a fixed<br>step-size in stationary environments as well as non-stationary ones.https://www.jsee.ir/article_715115_62e41efe0e0696e4db546366950fdfe6.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166927120250101Effect of High Axial Load on Overstrength Factor of Intermediate Links in EBFs495671521810.48303/jsee.2024.2030587.1094ENZahraGhafariM.Sc. Student, Department of Civil Engineering, Faculty of Civil Engineering and Transportation, University of Isfahan,
Isfahan, IranMasoodMojaradPh.D. Student, Department of Civil Engineering, Faculty of Civil Engineering and Transportation, University of Isfahan,
Isfahan, IranMaryamDaeiAssociate Professor, Department of Civil Engineering, Faculty of Civil Engineering and transportation, University of Isfahan,
Isfahan, IranJournal Article20240529Eccentric bracing frames (EBFs) are one of the most suitable seismic resistance systems due to their high strength, ductility, and energy dissipation. In some EBF configurations, due to loading patterns or structural geometry, the link member can be subjected to a high axial load. The presence of high compressive axial loads increases the occurrence of buckling and thus reduces both its strength and ductility. Most of the studies conducted have focused on short links, and as mentioned in the commentary of the AISC seismic regulations, the effect of axial load on the behavior of intermediate and long links has not been sufficiently investigated, which highlights the need for further study. In this research, numerical modeling is first validated by experimental results. Subsequently, the overstrength factor of intermediate links made from European I-shaped sections subjected to axial loads is examined. The results indicate that the overstrength factor of intermediate links is lower than the prescribed value of 1.5 in the provisions.https://www.jsee.ir/article_715218_5bfac1f7a9341df9f473796a4f7877f3.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166927120250101The Cyclic Behavior Assessment for Equipped Frames with the Novel Load-Resisting System: Eccentric-Braced Frames with Steel Shear Plate Infills577171521610.48303/jsee.2024.2031989.1100ENRezaKhalili SarbangoliPh.D. Student, Department of Civil Engineering, Maragheh Branch, Islamic Azad University, Maragheh, IranAhmadMalekiAssistant Professor, Department of Civil Engineering, Maragheh Branch, Islamic Azad University, Maragheh, Iran0000-0002-4649-4347RaminK.BadriAssistant Professor, Department of Civil Engineering, Azarshahr Branch, Islamic Azad University, Azarshahr, IranJournal Article20240611One of the important advantages of steel plate shear walls (SPSWs) is the possibility of creating openings with various geometric dimensions and in different positions on the steel plate. The goal is to offer a novel kind of steel shear walls with an eccentric brace and enhance the system's seismic behavior by including a brace at the opening edges. To evaluate the performance of the proposed frames, a finite element analysis was used, considering the nonlinear parameters of materials and geometry under cyclic loading. The findings of the numerical models reveal that transforming the infill plate's surface into regular and smaller geometric forms causes the plate's buckling mode. Moreover, the extension of the braces and their connection to the bottom of the beam creates diagonal tension fields in the plate and prevents local buckling of the plate at the opening edge.https://www.jsee.ir/article_715216_65775986a9b9ac5cae56434b6626386f.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166927120250101Collapse Mechanism Investigation of Mass-Isolated Systems738771525410.48303/jsee.2024.2038378.1119ENSaeidSaharkhizanPh.D. Candidate, Structural Engineering Research Center, International Institute of Earthquake Engineering and Seismology
(IIEES), Tehran, Iran0009-0000-6929-4842MansourZiyaeifarAssociate Professor, Structural Engineering Research Center, International Institute of Earthquake Engineering and Seismology
(IIEES), Tehran, IranJournal Article20240814Rare earthquakes cause heavy damages to building structures. Design of structures using yield mechanisms that provide extra resources to ensure structural stability for intensity higher than the design-based earthquake (DBE), can be considered as a reasonable technique to reduce the collapse probability. In this regard, the design of a mass-isolated structural system with a multi-phase seismic behavior as a reliable lateral load-bearing system has been investigated. In this type of configuration, by separating the mass from the stiffness of the system in the vertical direction, the structural system is transformed into two subsystems (soft and stiff), which can be utilized as an<br>effective damping amplification technique by using an appropriate energy dissipation mechanism between these two parts. Furthermore, it can be used as an efficient seismic rehabilitation method for non-code-confirmed structures. In this study, in addition to performing parametric studies to determine the optimal damping coefficient, the impact and ultimate collapse mechanism of the system have been simulated and investigated numerically. The results of nonlinear time history analysis indicate that the mass-isolation technique can efficaciously improve the seismic performance of buildings compared to conventional structural systems due to the multi-phase seismic<br>behavior.https://www.jsee.ir/article_715254_24b0cd4c12a71d434f3a65b0b30dbbf0.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166927120250101Effect of Composite Action on Seismic Response of Steel Structures with Dampers Designed by the DDBD Method8910271606610.48303/jsee.2024.2034260.1110ENSeyed BehdadAlehojjatResearcher in Structural Engineering, Department of Civil Engineering, Qa. C., Islamic Azad University, Qazvin, Iran0000-0003-2450-9381MasoodYakhchalianAssistant Professor, Department of Civil Engineering, Qa. C., Islamic Azad University, Qazvin, Iran0000-0003-2672-6187OmidBaharAssociate Professor, Structural Engineering Research Center, International Institute of Earthquake Engineering & Seismology
(IIEES), Tehran, Iran0000-0002-9655-4512Journal Article20240701This paper investigates two important engineering demand parameters for assessing seismic performance of steel moment resisting frames equipped with linear fluid viscous dampers designed using the modified direct displacement-based design (DDBD) method. These parameters include the inter-story drift ratio (IDR) and the residual inter-story drift ratio (RIDR). For this aim, nonlinear dynamic time history analyses are performed at two seismic hazard levels, involving the design basis earthquake (DBE) and the maximum considered earthquake (MCE). The effects of panel zone flexibility and gravity framing are modeled in the analyses. In addition, the effect of considering and neglecting composite action on gravity framing and beam elements in moment resisting frames is investigated. The results show that in<br>both cases, the structures designed using the modified DDBD method could acceptably meet the performance target IDR limit. Additionally, it is shown that accounting for the effect of composite action leads to a reduction of about 4% in the maximum value of mean IDRs at both the DBE and MCE hazard levels. However, an increase of up to 12% is obtained for the maximum value of median RIDRs at the MCE level when the composite action is considered.https://www.jsee.ir/article_716066_567b7c54f21e7be84ac78c83a2253614.pdf