International Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166922420201101Bayesian and Non Parametric Estimation of ETAS Models Applied to Seismic Recurrence in Ecuador 201612725464710.48303/jsee.2022.254647ENFausto FabianFernandezMSc. Graduate, San Francisco de Quito University National Polytechnic University, San Francisco de Quito UniversityCarlos JimenezMosqueraPh.D. San Francisco de Quito University National Polytechnic University, San Francisco de Quito UniversitJournal Article20171017In this paper our purpose is to analyze, from the Bayesian point of view, the occurrence rate of earthquakes in Ecuador since March 2016 to July 16, 2016. We implemented in Stan language the ETAS models, starting with the purely temporal model, then considering the magnitudes, and later the spatio-temporal models (both isotropic and anisotropic), and finally the hypo-central model. We introduced the use of Welzl algorithm to evaluate the log-likelihood of the occurrence rate for spatio-temporal models. We conducted simulations by extracting values from the a posteriori distributions of the models parameters, to obtain estimations of the accumulated number of earthquakes (with magnitude greater than a threshold) and the behaviour of inter-time events. The estimations are validated with the observed from July 16 2016 to September 2016.https://www.jsee.ir/article_254647_86646b13fed6dc496690db6e0a22834b.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166922420201101Utilization of Neural Network in Seismic Refraction Data Processing293969976510.48303/jsee.2022.560648.1022ENRezaKhajaviAssistant Professor, Ferdowsi University of Mashhad, Mashad, IranGholamJavan-DoloeiAssociate Professor, Seismology Research Center, International Institute of Earthquake
Engineering and Seismology (IIEES), Tehran, Iran0000-0002-6546-2412NaimehKhorshidiM.Sc. Student, Ferdowsi University of Mashhad, Mashad, IranJournal Article20220821Increasing our understanding of the earth's layering characteristics at an engineering scale is crucial for the optimal design of tall buildings, important industrial facilities, and lifelines infrastructures. The most important characteristics that can be measured by the seismic refraction method is the speed of longitudinal and transverse seismic waves. In addition, determining the thickness of layers up to depth of 150 meters is another capability of this method. In this research, the classical refraction seismic method has been compared with methods based on artificial intelligence techniques with emphasis on two types of fully connected and convolution neural network techniques. The results of this research show that by replacing the neural network that fits the characteristics of the subsurface layers instead of using classical inversion methods, the accuracy of classical inversion methods can be achieved in much less time. Fully connected and convolutional neural networks are highly capable for identifying geological structures, whose measurement data is contaminated with noise, with acceptable accuracy without pre-processing. Therefore, our proposed method, in addition to the ability to detect the arrival time of seismic phases in noisy signals and the time-consuming process of manual processing, is likely to be useful for identifying complex geological formations.https://www.jsee.ir/article_699765_8637e7bfddcc1ad02797c041eaa576eb.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166922420201101On the 2D Characteristics of Small-Scale Trapezoidal Sedimentary Basins415424779210.48303/jsee.2021.247792ENRezaMovahed AslPh.D. Student, Disaster Risk Management Research Center, International Institute of
Earthquake Engineering and Seismology (IIEES), Tehran, IranMohammadGhayamghamianProfessor, Disaster Risk Management Research Center, International Institute of Earthquake
Engineering and Seismology (IIEES), Tehran, IranJournal Article20210407Recent researches clearly revealed that the 1D lateral model fail to reproduce actual site response characteristics in complex wave propagation field. In spite of many available researches on 2D or 3D effects of large-scale basins, different 2D or 3D behavior of small-scale sedimentary basins, are not well understood and explained. In the previous study, the authors studied the effects of small-scale basins and found it very important, depending on the shape of the lateral irregularities. Among different shapes of lateral irregularities, the small trapezoidal basin shows special site amplification characteristics, which need to be examined further. In this paper, different aspects of small-scale trapezoidal basins such as slope angle, basin length, infill soil properties and basin thickness are parametrically investigated to clarify those effects on strong ground motion characteristics. For this purpose and in the absence of recorded earthquake data on such lateral irregularities, extensive parametrical studies are carried out by using finite difference numerical analysis. Then, huge numbers of trapezoidal small basin models are constructed and are simultaneously subjected to the earthquake motions in both horizontal and vertical directions. The site response at the points along the basin are analyzed in the frequency domain using Fourier spectral ratio, and in the time domain using the ratio of 2D horizontal and vertical peak ground accelerations with respect to 1D ones are defined as the horizontal and vertical aggravation factors (AG<sub>H</sub> and AG<sub>V</sub>). The AG<sub>H</sub> and AG<sub>V</sub> factors show large sensitivity to infill soil properties and thickness as well as slope angle. The AG<sub>H</sub> shows large variation in the middle of small trapezoidal basin in the range of 1.5 to 2. Meanwhile, the AG<sub>V</sub> shows large variation around the two basin edges with the values of 1.5 to 2.5. Finally, the outcomes provide some recommendations in design, and emphasize on the importance of 2D analysis in site effect estimation of small-scale trapezoidal basin.https://www.jsee.ir/article_247792_3164c0c476b4d88e4ca28656493260e7.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166922420201101Study of Seismic Performance of Self-Centering Steel Plate Shear Walls at DBE and MCE556825230310.48303/jsee.2022.252303ENSorourArjmandzadehPh.D. Candidate, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, IranAbdolrezaS. MoghadamAssociate Professor, Structural Engineering Research Center, International Institute of
Earthquake Engineering and Seismology (IIEES), Tehran, IranJournal Article20220208Self-Centering Steel Plate Shear Wall (SC-SPSW) is a promoted steel shear wall in which steel web plates absorb the seismic energy and Self-Centering connections bring the structure back to its original position after a ground motion. The main goals of this seismic resisting system are mitigating plastic damage in the mail structural elements such as beams and columns and reducing the residual drift after the earthquake. This paper offers a study to evaluate the efficiency of this innovative system in midrise buildings at Design Based Earthquake (DBE) and Maximum Credible Earthquake (MCE). Three archetypes which are five, seven and ten story office buildings are prepared to be representative of midrise buildings. Each archetype is designed to bear 4% gap opening at the connections. Infill plates alone can resist 100% of the specified seismic load without considering boundary frame moment resistance. Nonlinear dynamic analysis under a set of far-field ground motion consisting of seven records is performed to estimate the seismic performance of the archetypes. The results of the dynamic analysis consisting main structural damage, inter-story drift and residual drift are studied to assess the efficiency of Self-Centering Steel Plate Shear Wall. According to the analysis results, the residual drifts of all archetypes were significantly reduced and full self-centering was achieved at both DBE and MCE level. In addition, beams and columns demonstrated no plastic deformation in nonlinear dynamic analysis at DBE and MCE ground motion, which is a great achievement to keep the main structural element safe during the earthquake. Inter-story drift in the archetype was below the allowable amount suggested by seismic design code except for upper stories that could be improved by choosing proper thickness for upper web plates.https://www.jsee.ir/article_252303_bf591e75f9ee8d1eaddb47edd0694235.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166922420201101Seismic Responses of Innovative Vertically Isolated Liquid Storage Tanks under Near-Fault and Far-Fault Ground Motions698224940510.48303/jsee.2022.249405ENMortezaMoeiniAssistant Professor, University of Zanjan, Zanjan, IranMohammad AliGoudarziAssociate Professor, Structural Engineering Research Center, International Institute of
Earthquake Engineering and Seismology (IIEES), Tehran, IranJournal Article20200909<span style="font-size: 11.0pt; line-height: 150%;">The seismic response of aboveground liquid storage tanks isolated by the proposed vertical isolation system (VIS) is investigated under near-fault and far-fault ground motions. For this purpose, a set of 14 ground motions including seven far-fault and seven pulse-like near-fault motions have been considered. Effectiveness of VIS is evaluated theoretically and numerically in selected tanks with different geometries including Short-Broad, Tall-Broad, Short-Slender, and Tall-Slender. In the proposed isolation system, the tank shell is detached from the base and supported on a ring of vertical isolators, and then the forces in the vertical direction caused by the overturning moment are isolated as an alternative to the common horizontal system used for shear base isolation of storage tanks. The equations of motion for a liquid tank equipped with the proposed system were extracted using the mass-spring simpliļ¬ed model of contained liquid. A study was performed by employing the non-linear solution of the governing equations and the effectiveness of the proposed system for selected tanks is discussed. To measure the effectiveness of the isolation system, the seismic response of isolated steel tanks is compared with that of the non-isolated (or fixed-base) tanks. The results of this study demonstrate the influence of the tank's geometries, characteristics of the isolation system, and input excitation features. These parameters should be reasonably selected to achieve the maximum mitigation of seismic responses in the tanks equipped with the VIS. Excitation parameters, PGV/PGA ratio of input records, and pulse period in two sets of ground motions are defined to recognize the variety of responses. It is confirmed that the VIS performs well under both near and far-fault motions but near-fault earthquakes amplify the seismic responses more than the far-fault records especially in broad tanks.</span>https://www.jsee.ir/article_249405_ab9cd4c4618f3e57370c03d0625c5d41.pdfInternational Institute of Earthquake Engineering and SeismologyJournal of Seismology and Earthquake Engineering1735-166922420201101A New Model for Estimating the Value of Human Loss for Cost-Benefit Analysis in Disaster Risk Management in Iran839425354810.48303/jsee.2022.253548ENSanaAzimiM.Sc. Graduate, International Institute of Earthquake Engineering and Seismology (IIEES),
Tehran, IranKambodAmini HosseiniAssociate Professor, Earthquake Risk Management Research Center, International Institute of
Earthquake Engineering and Seismology (IIEES), Tehran, Iran0000-0002-5989-8826HoomanMotamedAssistant Professor, Earthquake Risk Management Research Center, International Institute of
Earthquake Engineering and Seismology (IIEES), Tehran, IranJournal Article20220208This research provides a new methodology for evaluating the socioeconomic consequences of earthquakes by reconsidering the debated topic of the value of human loss in the course of disaster loss estimation in Iran. To do this, at first, the relevant methodologies have been investigated, and then the consistency of the results of those methods with the existing norms in Iran has been assessed. Then, a model was proposed to estimate the Value of Human Loss (VHL) to be used in cost-benefit analyses in disaster risk management planning. Finally, the proposed model has been applied to estimate the economic loss arising from the individual's death due to a seismic event in a vulnerable neighborhood in Tehran. The results of this study depicted that the outputs of the proposed model could provide a more tangible understanding of the earthquake losses to decision-makers. Also, it can facilitate the economic analysis required for various stages of disaster management, in particular, choosing more economically-justified risk reduction options. In addition, it can be used for evaluating the importance and urgency of earthquake risk mitigation in different urban and rural places. The proposed methodology can be applied in other countries with certain modifications based on differences in socio-economic characteristics.https://www.jsee.ir/article_253548_3c0f96fa125737f51438923fb1a99431.pdf