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EditorialPublication Metadata only Eulogy to Professor Nicholas N. Ambraseys(Springer Science+Business Media, 2013-02) Ansal, Mustafa Atilla; Civil Engineering; ANSAL, Mustafa AtillaSadly, at the final phase of all these preparations for Vol.11 N.1, our very dear and very distinguished Editorial Board Member Prof. Nicholas Ambraseys passed away on December 28, 2012 at the age of 83. Prof. Ambraseys played a very positive and crucial role in the initiation of the Bulletin of Earthquake Engineering ten years ago. He attended the EAEE Executive Committee Meeting held in Lisbon on September 16, 2000 and supported the publication of a new technical journal as the official journal of EAEE. As the Editorial Board of BEE, we believe it would be very appropriate to dedicate this issue to our great mentor, colleague and great researcher, Professor Nicholas Ambraseys. He recently submitted two manuscripts to be published in BEE. The first one “Assessment of the long-term seismicity of Athens from two classical columns” was published in the V.10 N.6 (2012). The second one “Ottoman archives and the assessment of the seismicity of Greece 1456–1833” is in the review stage.ArticlePublication Metadata only Multi-criteria decision-making model for risk management in modular construction projects(Taylor & Francis, 2024) Khodabocus, Sabah Fatima; Seyis, Senem; Civil Engineering; KAZAZOĞLU, Senem Seyis; Khodabocus, Sabah FatimaThe modular sector needs a precise guide to determine the most efficient risk management approaches. The main research objective of this study is to develop a multi-criteria decision-making model to find the most efficient risk management approach according to the relevant risk criteria. The risk criteria and risk management approaches for modular construction projects were also identified and classified within this scope. A systematic literature review, semi-structured interviews, and open-ended questionnaires were performed for identification and classification purposes. For ranking and quantifying the identified risks and risk approaches, as well as developing the decision-making model, the Delphi method and the Analytical Hierarchy Process (AHP) were conducted. A two-round Delphi method, with eleven experts, was conducted to achieve efficient performance scores of the identified risk management approaches. The percentage standard deviation decreased, Relative Importance Index (RII), Cronbach’s alpha, and Kendall’s coefficient of concordance (Kendall’s W) were calculated to ensure the outputs’ reliability, validity, and agreement level. The AHP method opted to quantify the Delphi method outputs, solve the multi-criteria decision-making process, and develop the multi-criteria decision-making model for risk management of modular construction projects. Triangulation results show that the critical risk categories are supply chain, health and safety, stakeholders, and governmental support. Lean principles such as the Last Planner System, Value Stream Mapping, Just in Time, and Kaizen are top-rated risk management approaches. This research’s novelty is identifying and analyzing crucial risk categories, providing the relevant risk management approaches ranked according to efficiency performance, and presenting a decision-making model as a guideline for risk management of modular construction projects.ArticlePublication Metadata only Energy-based sidesway collapse fragilities for ductile structural frames under earthquake loadings(Elsevier, 2018-11) Deniz, Derya; Song, J.; Hajjar, J. F.; Civil Engineering; DENİZ, DeryaIn assessing the likelihood of structural collapse under strong earthquake motions, uncertainties in structural properties and ground motions can be incorporated by use of a probabilistic analysis framework in conjunction with analysis methods such as incremental dynamic analysis (IDA). Maximum inter-story drift ratio (IDR) is typically selected as the key descriptor to characterize the global behavior of structural system in such a probabilistic assessment. The structural collapse capacity is often defined in terms of a threshold value of IDR or a reduced slope of the IDA curve between a selected seismic intensity measure and the corresponding IDR. However, collapse assessment approaches based on IDR may not accurately represent the overall structural collapse behavior due to redistribution and variation of local damage within the structure. Moreover, results of collapse predictions are found to be sensitive to variability in such drift measures, and assumed threshold values used in the collapse criterion. Recently, an energy-based seismic collapse criterion has been developed to describe collapse in terms of dynamic instability of the whole structural system caused by gravity loads. Using the energy-based collapse criterion, this paper proposes a more effective sidesway collapse risk assessment approach of ductile planar frames subjected to horizontal seismic loadings based on a new key descriptor of structural performance. The key descriptor, designated as the equivalent-velocity ratio, is related to the ratio of the energy dissipated through structural degradation to the seismic input energy. Using the equivalent-velocity ratio, a probabilistic collapse assessment method is developed for systematic treatment of uncertainties in the ground motions.Book ChapterPublication Metadata only Design of energy-efficient white portland cement mortars for digital fabrication(Springer, 2020) Kurt, S.; Atalay, Yiğit Alper; Aydın, Ozan Eray; Avcıoğlu, B.; Yıldırım, T.; Göktepe, G. B.; Emir, S.; Bundur, Zeynep Başaran; Paksoy, H. Ö.; Civil Engineering; Bos, F. P.; Lucas, S. S.; Wolfs, R. J. M.; Salet, T. A. M.; BUNDUR, Zeynep Başaran; Atalay, Yiğit Alper; Aydın, Ozan ErayAdditive manufacturing, i.e. three-dimensional (3D) printing technology has many advantages over traditional processes and the related technology is continuously improving. This study aims to develop an energy- efficient White Portland cement (WPC) mortar mix suitable for 3D printing applications. The mortar mix contained a blended binder content using Çimsa Recipro50 calcium aluminate cement (CAC) along with Çimsa Super WPC (sWPC). Microencapsulated Phase Change Materials (mPCMs) added to the mix enhance thermal performance through latent heat storage capability. The CAC used in the study has an alumina content of at least 50% Mineralogical analysis of the CAC and sWPC binder were characterized by the XRD-Rietveld method. In terms of material design for 3D printing, printable mortars must be workable enough to be extruded (extrudability) and retain its shape with little or no deformation after extrusion (buildability). In this study, the printability of mortar was evaluated through workability loss, open time, green strength, and early-age compressive strength. Results showed that use of sWCP and CAC composite enables a thixotropic behavior, which is required for 3D printing. The designed mortar mixes can enable high flowability necessary for successful extrusion and have high green strength at fresh state to maintain stable printing. The results also showed that the use of mPCMs can influence printability while improving buildability.EditorialPublication Metadata only Preface(Springer, 2023) Atalar, C.; Çinicioğlu, Safiye Feyza; Civil Engineering; ÇİNİCİOĞLU, Safiye FeyzaN/AArticlePublication Metadata only Seismic design and performance of SPSWs with beam-connected web plates(Elsevier, 2018-03) Özçelik, Ahmet Yiğit; Clayton, P. M.; Civil Engineering; ÖZÇELİK, Ahmet YiğitSteel plate shear walls with beam-connected web plates (B-SPSWs) are an alternative steel plate shear wall (SPSW) configuration in which the web plate edges are detached from the columns to avoid high flexural demands in the columns resulting from tension field action. Releasing the columns from the web plates results in development of a partial tension field instead of the full tension field observed in conventional SPSWs, which changes system behavior and member demands significantly. A numerical study is undertaken to assess the seismic performance of B-SPSWs designed for low-seismic regions. Equations for the web plate lateral strength and the beam axial force, shear force, and moment demands are provided. Following two design approaches, eighteen B-SPSWs possessing different geometric characteristics are designed based on the provided equations. Each B-SPSW is subjected to forty ground motions representing two seismic hazard levels. The seismic performance of these B-SPSWs is evaluated based on maximum interstory drifts, member demand-to-capacity ratios, and beam-column connection rotations. The results indicate that B-SPSWs show a promising seismic behavior and may be particularly attractive lateral force-resisting alternatives for regions of low and moderate seismicity. (C) 2017 Elsevier Ltd. All rights reserved.ArticlePublication Open Access Case study for comparative analysis of BIM-based LEED building and nonLEED building(Pamukkale Üniversitesi, 2022) Seyis, Senem; Civil Engineering; KAZAZOĞLU, Senem SeyisThe objective of this study is to design a sustainable high-rise residential building using Leadership in Energy and Environmental Design (LEED) and Building Information Modeling (BIM), and perform comparative analysis for the LEED building and non-LEED building. Within this scope, break-even points of these buildings’ water and energy consumptions as well as additional costs related to sustainability were analyzed. The research methodology relies on the literature review and case study. In the case study, the 3D model of a 15-storey residential building was designed via Autodesk Revit 2019 based on the LEED v4.1 Building Design and Construction (BD+C) rating system. The case study building can achieve 31 credits and 9 prerequisites which allow to obtain 61 points and LEED Gold certificate. By applying LEED v4.1 BD+C procedures, water consumption of the building was reduced by 65.96%, and energy consumption of the building was decreased by 59%. The initial cost of this LEED building is 1.074.833,04 TL which is 852.230.64 TL higher than the initial cost of non-LEED building. According to the break-even point calculations, the initial cost of LEED building can be charged after 13 years 8 months and 12 days. Results make a significant contribution to the literature and industry by showing the requirements and design process of a high-rise residential building using LEED and BIM. This study adds original value to the literature and industry by ensuring practitioners and researchers with constructive information about the energy, water, and cost performance of the LEED buildings. Further, results provide an insight to professionals in the architecture, engineering, and construction industry about the value of green buildings.ArticlePublication Metadata only Uncertainty in risk of highway bridges assessed for integrated seismic and flood hazards(Taylor and Francis, 2017-11-24) Yılmaz, Taner; Banerjee, S.; Johnson, P. A.; Civil Engineering; YILMAZ, TanerProbabilistic risk assessment for bridges under natural hazards is of great interest to engineers for the development of risk mitigation strategies and implementation plans. The present study evaluates risk of an existing highway bridge in California, USA, under the integrated impact of regional seismic and flood hazards. A sensitivity study combining tornado diagram and first-order second moment reliability analyses is conducted to screen significant uncertain parameters to which bridge response is mostly sensitive. A rigorous uncertainty analysis, employing random sampling and Monte Carlo simulation techniques, is performed to obtain variations in fragility and risk curves of the bridge. Observed variations in risk curves at various risk levels are quantified through 90% confidence intervals and coefficients of variation (COV) of risk. It is observed that uncertainty in the estimated risk increases due to the presence of flood hazard at the bridge site, although mean risk does not vary with flood hazard level. Research outcome signifies that the variation in risk due to parameter uncertainty and varied flood hazard level should not be ignored to ensure bridge safety under the stated multi-hazard condition.Conference paperPublication Metadata only Evaluation of code provisions for seismic performance of unachored liquid storage tanks(2017) Erkmen, Bülent; Civil Engineering; ERKMEN, BülentSeismic performance of two unanchored liquid-storage tanks with tank diameter of 24.5 m and 36 m and operating liquid height of 12.2 m and 20.0 m, respectively were investigated using Coupled Eulerian-Lagrangian (CEL) and mechanical spring-mass analogy nonlinear finite element computational methods. The CEL approach includes the effects of higher modes of liquid vibration (sloshing), liquid breaking effects, and liquid-structure interaction during seismic loading. The modern seismic design provisions for liquid-storage tanks, on the other hand, are based on a mechanical spring-mass analogy. This approach neglects the higher vibration modes for the sloshing water, liquid-structure interaction, and effects of tank base uplift on seismic performance. For the tanks, base uplift histories were computed with both modeling approaches through nonlinear time history analysis performed using five recorded earthquake acceleration data. The uplift histories were compared to evaluate the adequacy of code seismic design provisions for unanchored tanks, and to determine whether the mechanical spring-mass analogy can be used to predict seismic performance of unanchored tanks. Analysis results show that the traditional mechanical spring-mass analogy, which is the basis for the current seismic design provisions, does not capture tank uplift history and its effects on dynamic loads. This approach underpredicts the total numbers of tank uplifts during seismic loading. The maximum tank base uplift computed using mechanical spring-mass analogy had an average error between 22% and 58 % for each tank. The results show that there is a need to developed a modify version of the traditional mechanical spring-mass analogy to be used for predicting seismic performance of unanchored liquid-storage tanks.ArticlePublication Metadata only A computational workflow for rupture‐to‐structural‐response simulation and its application to Istanbul(Wiley, 2020-10) Zhang, W. Y.; Restrepo, D.; Crempien, J. G. F.; Erkmen, Bülent; Taborda, R.; Kurtuluş, Aslı; Taciroglu, E.; Civil Engineering; ERKMEN, Bülent; KURTULUŞ, AsliScenario-based earthquake simulations at regional scales hold the promise in advancing the state-of-the-art in seismic risk assessment studies. In this study, a computational workflow is presented that combines (i) a broadband Green's function-based fault-rupture and ground motion simulation-herein carried out using the "UCSB (University of California at Santa Barbara) method", (ii) a three-dimensional physics-based regional-scale wave propagation simulation that is resolved at fmax=11.2 Hz, and (iii) a local soil-foundation-structure finite element analysis model. These models are interfaced with each other using the domain reduction method. The innermost local model-implemented in ABAQUS-is additionally enveloped with perfectly matched layer boundaries that absorb outbound waves scattered by the structures contained within it. The intermediate wave propagation simulation is carried out using Hercules, which is an explicit time-stepping finite element code that is developed and licensed by the CMU-QUAKE group. The devised workflow is applied to a 80x40x40 km3 region on the European side of Istanbul, which was modeled using detailed soil stratigraphy data and realistic fault rupture properties, which are available from prior microzonation surveys and earthquake scenario studies. The innermost local model comprises a chevron-braced steel frame building supported by a shallow foundation slab, which, in turn, rests atop a three-dimensional soil domain. To demonstrate the utility of the workflow, results obtained using various simplified soil-structure interaction analysis techniques are compared with those from the detailed direct model. While the aforementioned demonstration has a limited scope, the devised workflow can be used in a multitude of ways, for example, to examine the effects of shallow-layer soil nonlinearities and surface topography, to devise site- and structure-specific seismic fragilities, and for calibrating regional loss models, to name a few.