18 research outputs found

    A Methodology For Coronary Stent Product Development: Design, Simulation And Optimization

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    Coronary stents are slotted tubes made of metals, alloys, or polymers. They are deployed in human arteries, which are blocked by calcified plaque, to keep the arteries open and allow the blood to flow with ease. Coronary stents have been proven as an effective treatment device for heart diseases such as acute myocardial infarction. Design plays an important role for coronary stents to perform the clinical functions properly. Various parameters such as materials, structures, dimensions, and deployment methods etc., need to be considered in the design of coronary stents. There are numerous studies on design of coronary stents and many significant manufacturing methods have been reported in the past two decades. However, there is no comprehensive methodology for the product development of coronary stents in terms of design, simulation, and manufacturing. The objective of this research is to develop a methodology for coronary stents product development that focuses on design, simulation, and manufacturing. The methodology brings together insights from numerous engineering design disciplines with the aim of making coronary stent development more flexible and more cost-efficient The product development methodology for coronary stents is executed through modeling and analyzing stent designs with details of design, simulation, and optimization methods. Three innovative stent designs are modeled using engineering design software (SolidWorks) and mechanical performances are simulated, evaluated, and optimized with the help of advanced engineering simulation software (ANSYS). In this study, the performance of stents based on stress, strain, and total deformation during deployment are analyzed and compared with commercially available optimal design i.e., Cypher (J & J Co.) stent, which acts as a benchmark design

    Optimization of a transcatheter heart valve frame using patient-specific computer simulation

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    Purpose This study proposes a new framework to optimize the design of a transcatheter aortic valve through patient-specific finite element and fluid dynamics simulation. Methods Two geometrical parameters of the frame, the diameter at ventricular inflow and the height of the first row of cells, were examined using the central composite design. The effect of those parameters on postoperative complications was investigated by response surface methodology, and a Nonlinear Programming by Quadratic Lagrangian algorithm was used in the optimization. Optimal and initial devices were then compared in 12 patients. The comparison was made in terms of device performance [i.e., reduced contact pressure on the atrioventricular conduction system and paravalvular aortic regurgitation (AR)]. Results Results suggest that large diameters and high cells favor higher anchoring of the device within the aortic root reducing the contact pressure and favor a better apposition of the device to the aortic root preventing AR. Compared to the initial device, the optimal device resulted in almost threefold lower predicted contact pressure and limited AR in all patients. Conclusions In conclusion, patient-specific modelling and simulation could help to evaluate device performance prior to the actual first-in-human clinical study and, combined with device optimization, could help to develop better devices in a shorter period

    Analisis Interaksi Aliran Darah dan Pembuluh Serta Pengaruh Kebebasan Mesh Pada Simulasi Hemodinamik Berbasis Metode Elemen Hingga

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    Cardiovascular diseases are the world’s leading cause of death with significant death rates caused by abnormalities in vessels such as aneurysms and stenosis. These conditions can potentially cause blockage and thinning of vessels which may lead to heart attack, stroke, and bleedings. Recently, computational simulation methods are frequently used in blood flow analysis. These methods are frequently used in vascular fluid dynamics analysis which relate to the origin of a disease, efficacy prediction in installation of therapeutic instruments and complements the in vitro studies. This article presents an example of a simple vascular simulation to study the effect of blood flow with respect to vascular wall displacement. Furthermore, this research shows the importance of formal CFD pre-processing such as mesh independence testing which influences the simlation accuracy as well as vascular flow prediction and its effects on vascular wall displacement. In this research, it is concluded that the number of mesh elements affects the accuracy of vascular wall shear stress (WSS) calculations with average WSS difference of 0.8 Pa with no significant difference in wall displacement values. An average WSS of 1.95 Pa and a wall displacement of 5.7 µm are obtained from the blood flow simulation in this study

    Mechanical behavior of absorbable iron foams with hollow struts for bone scaffolding applications

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    Jusqu'à il y a quelques années, chaque année, aux États-Unis, plus de 500 000 personnes devaient réparer leurs défauts osseux. Il a été prédit que le besoin de telles réparations doublerait aux États-Unis et dans le monde d'ici 2020. Les techniques de greffe osseuse sont couramment utilisées pour guérir de gros défauts osseux. Cependant, la greffe osseuse présente certains inconvénients tels que l'infection, la douleur, la morbidité et le manque de site donneur. L'échafaudage osseux est considéré comme une approche alternative pour guérir les défauts osseux sans complications liées à la greffe. Les échafaudages osseux sont considérés comme des implants temporaires, car après la formation de nouveaux tissus, leur présence n'est plus nécessaire. Des métaux poreux biodégradables (résorbables) ont été développés et étudiés en tant qu'échafaudages osseux temporaires. Ces structures poreuses fournissent un support mécanique et un espace biologique pour la régénération tissulaire. Ces implants se corrodent pendant le processus de régénération tissulaire et, idéalement, ils devraient disparaître une fois le processus de guérison terminé. Ainsi, aucune chirurgie secondaire pour les retirer ne serait nécessaire. Une tâche cruciale des échafaudages osseux résorbables est de fournir un support mécanique pour la formation de nouveaux tissus. Les échafaudages doivent conserver leur intégrité mécanique sans défaillance en raison des charges mécaniques appliquées à partir du milieu environnant. En revanche, en tant qu'implants orthopédiques, leur rigidité ne doit pas être supérieure à celle du tissu osseux environnant en raison du risque de stress shielding. Ainsi, la compréhension des facteurs influençant la réponse mécanique de l'échafaudage osseux lors de la dégradation et la prédiction de leurs propriétés mécaniques sont cruciales. La conception et la fabrication d'échafaudages résorbables sont un sujet d'intérêt pour les chercheurs. Des analyses détaillées qui expliquent les propriétés mécaniques post-corrosion des échafaudages métalliques résorbables en fonction de leurs caractéristiques architecturales post-corrosion font défaut dans la littérature. Ce projet de doctorat porte sur le comportement mécanique de la mousse de fer galvanisée à cellules ouvertes avec des entretoises creuses pour les applications d'échafaudage osseux. En particulier, les relations entre les propriétés structurales et mécaniques, les propriétés mécaniques après corrosion et les paramètres micro-architecturaux induits par la corrosion des mousses de fer ont été explorées. En outre, des modèles d'éléments finis idéalisés (mousse Kelvin) d'un témoin ainsi qu'un échantillon de mousse de fer corrodé ont été développés sur la base de mesures de tomographie micro-calculée et de modes de corrosion pour prédire la réponse mécanique post-corrosion de la mousse de fer (test in silico). La thèse comprend une introduction, trois chapitres contenant une revue approfondie de la littérature et les études menées pour le projet de doctorat, et une section Conclusion. Des données supplémentaires sur les études réalisées se trouvent en annexe. Dans l'introduction, un bref historique sur les échafaudages osseux, l'application de métaux poreux biodégradables (résorbables) dans les échafaudages, l'énoncé du problème, les objectifs de recherche, la stratégie de recherche et la nouveauté de cette recherche sont présentés. Le chapitre 1 contient une revue approfondie de la littérature sur les sujets pertinents au sujet de la thèse tels que l'application de métaux biodégradables comme implants temporaires, la fabrication et l'application de mousses métalliques résorbables comme échafaudages osseux ainsi que leurs propriétés mécaniques et de corrosion, temps de corrosion propriétés mécaniques dépendantes des échafaudages métalliques résorbables, approches de modélisation analytique et informatique pour prédire le comportement mécanique des mousses métalliques et modélisation informatique de la dégradation dans les métaux résorbables. Le chapitre 2 traite de la première étape du projet de doctorat qui était une étude sur les propriétés mécaniques des mousses de fer électrolytiques à cellules ouvertes avec entretoises creuses. Dans cette étude, des échantillons de mousses de fer aux propriétés architecturales différentes, c'est-à-dire la taille des alvéoles, l'épaisseur des branches et la taille des pores, ont subi des essais de compression mécanique et le rôle de leurs paramètres architecturaux ainsi que leur densité relative dans leurs différentes réponses à la compression (quasi-gradient élastique, élasticité et résistance à la compression) a été discuté. De plus, une modélisation par éléments finis des mousses Kelvin a été développée pour fournir une meilleure compréhension des effets de creux des entretoises sur les propriétés mécaniques de la mousse. Le chapitre couvre une introduction, la méthodologie, les résultats, la discussion et une section de conclusion. Le chapitre 3 traite des propriétés mécaniques post-corrosion et des configurations architecturales des mousses de fer à entretoises creuses. Les échantillons de mousse de fer ont subi des tests d'immersion dans une solution de Hanks jusqu'à 14 jours, suivis de tests de nettoyage et de compression mécanique. Les facteurs influençant les propriétés mécaniques de la mousse corrodée ont été explorés, c'est-à-dire la dégradation structurelle, les produits de corrosion adhérents et les changements micro-architecturaux au niveau des entretoises. une tomographie micro-calculée a été utilisée pour mesurer les paramètres architecturaux du contrôle et des mousses corrodées pendant 14 jours. Sur la base des mesures architecturales, des modèles d'éléments finis de mousse Kelvin ont été développés pour prédire la réponse mécanique des mousses corrodées. De plus, un nouveau modèle de mousse Kelvin a été développé pour prédire la réponse mécanique des mousses de fer corrodées sous corrosion homogène, le mécanisme de corrosion qui n'avait pas été observé dans les expériences. Enfin, les faits saillants les plus importants des études sont présentés dans la section Conclusion. Aussi, les limites et les bénéfices potentiels des résultats de ce projet pour les futurs travaux de recherche sont expliqués, et de nouvelles idées pour les futurs projets concernant le comportement mécanique des mousses métalliques résorbables sont proposées.Up to a few years ago, every year, in the Unites States, more than 500,000 people needed to repair their bone defects. It was predicted that the need for such repairs would double in US and worldwide by 2020. Bone grafting techniques are commonly used to heal large bone defects. However, there are certain drawbacks with bone grafting such as infection, pain, morbidity and shortage of donor site. Bone scaffolding is considered as an alternative approach to heal bone defects without complications raised from grafting. Bone scaffolds are considered as temporary implants, since after the formation of new tissue, their presence is not needed anymore. Porous biodegradable (absorbable) metals have been developed and studied as temporary bone scaffolds. These porous structures provide mechanical support and biological space for tissue regeneration. These implants corrode during tissue regeneration process, and, ideally, they should disappear once the healing process ends. Thus, no secondary surgery to remove them would be needed. One crucial task for absorbable bone scaffolds is to provide mechanical support for new tissue formation. The scaffolds must keep their mechanical integrity without failing due to mechanical loads applied from the surrounding environment. On the other hand, as orthopedic implants, their stiffness should not be higher than the surrounding bone tissue due to the risk of stress shielding. Thus, understanding the influencing factors on the mechanical response of the bone scaffold during degradation and predicting their mechanical properties are crucial. Design and fabrication of absorbable scaffolds is a topic of interest for researchers. Detailed analyses that explain the post-corrosion mechanical properties of absorbable metal scaffolds based on their post-corrosion architectural features are lacking in the literature. This PhD project addresses the mechanical behavior of electroplated open cell iron foam with hollow struts for bone scaffolding applications. In particular, the structural-mechanical properties relationships, post-corrosion mechanical properties and the corrosion-induced micro-architectural parameters of the iron foams have been explored. In addition, idealized finite element models (Kelvin foam) of a control as well as a corroded iron foam specimen were developed based on micro-computed tomography measurements and corrosion modes to predict the post-corrosion mechanical response of the iron foam (in silico test). The thesis comprises an Introduction, three chapters containing a thorough literature review and the studies conducted for the PhD project, and a Conclusion section. Additional data about the performed studies are found in the Appendix. In the Introduction, a brief background on bone scaffolds, the application of porous biodegradable (absorbable) metals in scaffolding, problem statement, research objectives, research strategy, and the novelty of the research are presented. Chapter 1 contains a thorough literature review on the subjects relevant to the topic of the thesis such as the application of biodegradable metals as temporary implants, fabrication and application of absorbable metal foams as bone scaffolds as well as their mechanical and corrosion properties, corrosion-time dependent mechanical properties of absorbable metallic scaffolds, analytical and computational modelling approaches to predict the mechanical behavior of metal foams and computational modeling of degradation in absorbable metals. Chapter 2 discusses the first step of the PhD project which was a study on the mechanical properties of the electroplated open-cell iron foams with hollow struts. In this study, samples of iron foams with different architectural properties, i.e. cell size, branch-strut thickness and pore size, underwent mechanical compression tests and the role of their architectural parameters as well as their relative density in their different compressive response (quasi-elastic gradient, yield and compressive strength) was discussed. In addition, finite element modeling of Kelvin foams was developed to provide a better understanding of the strut hollowness effects on the foam mechanical properties. The chapter covers an introduction, the methodology, results, discussion, and a concluding section. Chapter 3 discusses the post-corrosion mechanical properties and architectural configurations of the iron foams with hollow struts. The iron foam samples underwent immersion tests in a Hanks' solution up to 14 days which were followed by cleaning and mechanical compression tests. The factors influencing the corroded foam mechanical properties were explored, i.e. structural degradation, adherent corrosion products and micro-architectural changes on the strut level. micro-computed tomography was employed to measure architectural parameters of the control and the 14-day corroded foams. Based on the architectural measurements, Kelvin foam finite element models were developed to predict the mechanical response of the corroded foams. Also, a new Kelvin foam model was developed to predict the mechanical response of the corroded iron foams under homogeneous corrosion, the corrosion mechanism which had not been observed in the experiments. Finally, the most important highlights of the studies are presented in the Conclusion section. Also, the limitations and the potential benefits of the results of this project for the future research works is explained, and new ideas for the future projects concerning the mechanical behavior of absorbable metal foams is proposed

    Design optimization of energy absorption structures with origami patterns

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    Conventional thin-walled tubes are structurally simple with good energy absorption capacity. However, they usually exhibit high initial peak force and violent fluctuations of plateau force in crush, which are detrimental as energy absorbers. Besides, their collapse modes are highly sensitive to random defects from manufacturing inaccuracy. To overcome these shortcomings, a common approach is to introduce properly designed geometric imperfections on the tube to trigger the crushing procedure in controlled folding modes and reduce the crushing force fluctuations. But the conventional method of introducing geometric imperfections may significantly reduce the energy absorption capacity of the tube. To increase the energy absorption capacity of tubes, many approaches have been used, e.g., the employment of stiffening ribs and the introduction of buckling controller. However, these methods may result in complicated mechanical response without significantly reducing the initial peak force. It is challenging to simultaneously reduce the initial peak force and crushing force fluctuations while maintain or increase the energy absorption capacity when designing thin-walled energy absorption structures. Origami technology, usually applied in the kinetic engineering field, has potential in controlling the folding modes of thin-walled tubes and reducing the impact force. However, there are few applications for the energy absorption in terms of origami technology. Also, the influence of different origami patterns on the energy absorption capacities of conventional tubes has not been systematically studied. Therefore, it is essential and necessary to conduct a systematic investigation on the energy absorption of structures with origami patterns. In this thesis, tubular structures with different origami patterns were specially designed and investigated experimentally and numerically. Firstly, Yoshimura (diamond) patterns were introduced to circular tube to create two types of origami tubes, i.e., full-diamond tube and diamond tube. The mechanical responses of the newly designed origami tubes were investigated through experimentally validated numerical simulations considering different wall thickness. The results showed that pre-folded origami patterns could significantly reduce the initial peak force while increasing (in full-diamond tube) or maintaining (in diamond tube) the specific energy absorption as compared to conventional circular tubes in crush when the tube wall was sufficiently thin. An alternative design was performed by introducing smoothed dimpled ellipsoidal patterns other than origami hinge lines on tube surfaces. The pre-designed ellipsoidal patterns were arranged in staggered manner in circumferential (concaving inwards) and longitudinal (concaving outwards) directions. The influences of various design parameters, such as the aspect ratio of ellipse, the number of structural units, dimple depth and wall thickness, on the mechanical properties and energy absorption capacities of dimpled tubes were investigated systematically via numerical simulations and experiments. The results showed that properly designed dimpled tubes had substantially lower initial peak force and remarkably less fluctuation in crushing force than circular tubes, without significantly sacrificing the mean crushing force. Additionally, the influences of the number of structural units and the base material properties on the mechanical properties and energy absorption capacity of the full-diamond tubes were numerically investigated. The results showed that, as compared to the dimpled tubes, the initial peak force of full-diamond tubes with identical arrangement of structural units was relatively lower, while the mean crushing force could be higher if the structural units were properly arranged. It was also found that the material property had remarkable influence on the energy absorption capacity owing to the sensitivity of material constitutive relation on the buckling mode of full-diamond tubes. As multi-cell tubes have been reported to be able to enhance the specific energy absorption as compared to conventional single-cell tubes, the combination of the multi-cell feature and origami pattern may bring innovative structural designs for energy absorption. In this thesis, origami folding patterns were introduced on the external walls to guide the buckling procedure, while the internal ribs of the multi-cell tube worked as stiffeners to enhance the strength. Three novel types of multi-cell thin-walled tubular structures with pre-folded diamond origami patterns were then proposed. The influences of various structural parameters on the mechanical properties and energy absorption capacities were systematically investigated via experimentally validated numerical simulations. Based on the numerical results, multi-objective optimizations were performed on the specially designed tubes by linearly weighted average method, aiming to find the optimal designs with low initial peak force, high specific energy absorption and small fluctuation of the crushing force. The response surface method (RSM) was utilized in the optimizations to formulate the objective functions. Theoretical analyses were conducted based on simplified buckling models and a theoretical solution for the mean crushing force was derived for the quadruple-cell origami-patterned tubes. A series of optimal designs were obtained with balanced initial peak force, specific energy absorption and fluctuation of the crushing force. It was found from the results that origami-patterned and origami-triggered quadruple-cell tubes could maintain relatively high specific energy absorption (SEA) as compared to the conventional quadruple-cell square tube, while the origami-patterned quintuple-cell tubes have the highest values. Furthermore, dynamic tests on specific optimal multi-cell tubes were conducted by using drop weight tests. The influence of the origami patterns on the dynamic mechanical properties and the buckling mechanisms of multi-cell tubes were investigated by using experimentally validated finite element modelling. The results showed that, for the origami-patterned quadruple-cell tube, the optimal design obtained from the dynamic simulations had almost identical geometric dimensions to the quasi-static ones, while the design objectives of origami-triggered quadruple-cell tube were increased simultaneously as compared to the quasi-static model. For the origami-patterned quintuple-cell tube, no evident differences were found between the quasi-static and dynamic models

    Development of a multi-objective optimization algorithm based on lichtenberg figures

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    This doctoral dissertation presents the most important concepts of multi-objective optimization and a systematic review of the most cited articles in the last years of this subject in mechanical engineering. The State of the Art shows a trend towards the use of metaheuristics and the use of a posteriori decision-making techniques to solve engineering problems. This fact increases the demand for algorithms, which compete to deliver the most accurate answers at the lowest possible computational cost. In this context, a new hybrid multi-objective metaheuristic inspired by lightning and Linchtenberg Figures is proposed. The Multi-objective Lichtenberg Algorithm (MOLA) is tested using complex test functions and explicit contrainted engineering problems and compared with other metaheuristics. MOLA outperformed the most used algorithms in the literature: NSGA-II, MOPSO, MOEA/D, MOGWO, and MOGOA. After initial validation, it was applied to two complex and impossible to be analytically evaluated problems. The first was a design case: the multi-objective optimization of CFRP isogrid tubes using the finite element method. The optimizations were made considering two methodologies: i) using a metamodel, and ii) the finite element updating. The last proved to be the best methodology, finding solutions that reduced at least 45.69% of the mass, 18.4% of the instability coefficient, 61.76% of the Tsai-Wu failure index and increased by at least 52.57% the natural frequency. In the second application, MOLA was internally modified and associated with feature selection techniques to become the Multi-objective Sensor Selection and Placement Optimization based on the Lichtenberg Algorithm (MOSSPOLA), an unprecedented Sensor Placement Optimization (SPO) algorithm that maximizes the acquired modal response and minimizes the number of sensors for any structure. Although this is a structural health monitoring principle, it has never been done before. MOSSPOLA was applied to a real helicopter’s main rotor blade using the 7 best-known metrics in SPO. Pareto fronts and sensor configurations were unprecedentedly generated and compared. Better sensor distributions were associated with higher hypervolume and the algorithm found a sensor configuration for each sensor number and metric, including one with 100% accuracy in identifying delamination considering triaxial modal displacements, minimum number of sensors, and noise for all blade sections.Esta tese de doutorado traz os conceitos mais importantes de otimização multi-objetivo e uma revisão sistemática dos artigos mais citados nos últimos anos deste tema em engenharia mecânica. O estado da arte mostra uma tendência no uso de meta-heurísticas e de técnicas de tomada de decisão a posteriori para resolver problemas de engenharia. Este fato aumenta a demanda sobre os algoritmos, que competem para entregar respostas mais precisas com o menor custo computacional possível. Nesse contexto, é proposta uma nova meta-heurística híbrida multi-objetivo inspirada em raios e Figuras de Lichtenberg. O Algoritmo de Lichtenberg Multi-objetivo (MOLA) é testado e comparado com outras metaheurísticas usando funções de teste complexas e problemas restritos e explícitos de engenharia. Ele superou os algoritmos mais utilizados na literatura: NSGA-II, MOPSO, MOEA/D, MOGWO e MOGOA. Após validação, foi aplicado em dois problemas complexos e impossíveis de serem analiticamente otimizados. O primeiro foi um caso de projeto: otimização multi-objetivo de tubos isogrid CFRP usando o método dos elementos finitos. As otimizações foram feitas considerando duas metodologias: i) usando um meta-modelo, e ii) atualização por elementos finitos. A última provou ser a melhor metodologia, encontrando soluções que reduziram pelo menos 45,69% da massa, 18,4% do coeficiente de instabilidade, 61,76% do TW e aumentaram em pelo menos 52,57% a frequência natural. Na segunda aplicação, MOLA foi modificado internamente e associado a técnicas de feature selection para se tornar o Seleção e Alocação ótima de Sensores Multi-objetivo baseado no Algoritmo de Lichtenberg (MOSSPOLA), um algoritmo inédito de Otimização de Posicionamento de Sensores (SPO) que maximiza a resposta modal adquirida e minimiza o número de sensores para qualquer estrutura. Embora isto seja um princípio de Monitoramento da Saúde Estrutural, nunca foi feito antes. O MOSSPOLA foi aplicado na pá do rotor principal de um helicóptero real usando as 7 métricas mais conhecidas em SPO. Frentes de Pareto e configurações de sensores foram ineditamente geradas e comparadas. Melhores distribuições de sensores foram associadas a um alto hipervolume e o algoritmo encontrou uma configuração de sensor para cada número de sensores e métrica, incluindo uma com 100% de precisão na identificação de delaminação considerando deslocamentos modais triaxiais, número mínimo de sensores e ruído para todas as seções da lâmina

    Surrogate models for seismic and pushover response prediction of steel special moment resisting frames

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    For structural engineers, existing surrogate models of buildings present challenges due to inadequate datasets, exclusion of significant input variables impacting nonlinear building response, and failure to consider uncertainties associated with input parameters. Moreover, there are no surrogate models for the prediction of both pushover and nonlinear time history analysis (NLTHA) outputs. To overcome these challenges, the present study proposes a novel framework for surrogate modelling of steel structures, considering crucial structural factors impacting engineering demand parameters (EDPs). The first phase involves the development of a process by which 30,000 random steel special moment resisting frames (SMRFs) for low to high-rise buildings are generated, considering the material and geometrical uncertainties embedded in the design of structures. In the second phase, a surrogate model is developed to predict the seismic EDPs of SMRFs when exposed to various earthquake levels. This is accomplished by leveraging the results obtained from phase one. Moreover, separate surrogate models are developed for the prediction of SMRFs’ essential pushover parameters. Various machine learning (ML) methods are examined, and the outcomes are presented as user-friendly GUI tools. The findings highlighted the substantial influence of pushover parameters as well as beams and columns’ plastic hinges properties on the prediction of NLTHA, factors that have been overlooked in prior studies. Moreover, CatBoost has been acknowledged as the superior ML technique for predicting both pushover and NLTHA parameters for all buildings. This framework offers engineers the ability to estimate building responses without the necessity of conducting NLTHA, pushover, or even modal analysis which is computationally intensive

    Surrogate models for seismic and pushover response prediction of steel special moment resisting frames

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    For structural engineers, existing surrogate models of buildings present challenges due to inadequate datasets, exclusion of significant input variables impacting nonlinear building response, and failure to consider uncertainties associated with input parameters. Moreover, there are no surrogate models for the prediction of both pushover and nonlinear time history analysis (NLTHA) outputs. To overcome these challenges, the present study proposes a novel framework for surrogate modelling of steel structures, considering crucial structural factors impacting engineering demand parameters (EDPs). The first phase involves the development of a process by which 30,000 random steel special moment resisting frames (SMRFs) for low to high-rise buildings are generated, considering the material and geometrical uncertainties embedded in the design of structures. In the second phase, a surrogate model is developed to predict the seismic EDPs of SMRFs when exposed to various earthquake levels. This is accomplished by leveraging the results obtained from phase one. Moreover, separate surrogate models are developed for the prediction of SMRFs’ essential pushover parameters. Various machine learning (ML) methods are examined, and the outcomes are presented as user-friendly GUI tools. The findings highlighted the substantial influence of pushover parameters as well as beams and columns’ plastic hinges properties on the prediction of NLTHA, factors that have been overlooked in prior studies. Moreover, CatBoost has been acknowledged as the superior ML technique for predicting both pushover and NLTHA parameters for all buildings. This framework offers engineers the ability to estimate building responses without the necessity of conducting NLTHA, pushover, or even modal analysis which is computationally intensive
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