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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Seismic Analysis of Norra Tornen : A Comparison Based on the Requirements in Eurocode 8

Barbaranelli, Andreas, Wallin, Andreas January 2019 (has links)
In Sweden, buildings are not designed to withstand earthquakes due to the rarity of an earthquake event and its consequential damage. However, the aim of this thesis was to study the seismic performance of some of the highest buildings in Stockholm, called Innovationen and Helix. The purpose of the study was to get an understanding of earthquake engineering for high rise buildings and to compare the behavior of the two towers during seismic action. In order to compare the two buildings and get an understanding of what will affect the seismic performance, Eurocode 8 was used. The Eurocode standard lists several properties that impacts the seismic resistance of buildings. One of the goals was to study how those factors influence the behavior of Innovationen and Helix and finally compare the results to each other in order to draw valid conclusions. The method to perform the analysis was a modal analysis using a finite element analysis program. The program used contains predefined response spectra’s based on Eurocode 8 which is used to define the seismic load acting on the structures. The extracted results are listed below: - Frequencies and mode shapes - Modal masses - Level and total masses - Accelerations - Displacements The conclusion of the study was that Innovationen and Helix have similar properties and some points from Eurocode 8 were better fulfilled by Helix and others by Innovationen: - Uniformity, symmetry and redundancy (Innovationen fulfills the requirements better than Helix) - Bi-directional resistance and stiffness (Innovationen fulfills the requirements better than Helix) - Torsional resistance and stiffness (Helix fulfills the requirements better than Innovationen) - Adequate foundation (Helix fulfills the requirements better than Innovationen) Of the two parameters studied, the height was the one with the most influence on seismic resistance.
52

Uncertainty treatment in performance based seismic assessment of typical bridge classes in United States

Mehdizadeh, Mohammad 01 January 2014 (has links)
Bridge networks are expensive and complex infrastructures and are essential components of today's transportation systems. Despite the advancement in computer aided modeling and increasing the computational power which is increasing the accessibility for developing the fragility curves of bridges, the complexity of the problem and uncertainties involved in fragility analysis of the bridge structures in addition to difficulties in validating the results obtained from the analysis requires precaution in utilization of the results as a decision making tool. The main focus of this research is to address, study and treatment of uncertainties incorporated in various steps of performance based assessments (PBA) of the bridge structures. In this research the uncertainties is divided into three main categories. First, the uncertainties that come from ground motions time and frequency content alteration because of scarcity of the recorded ground motions in the database. Second, uncertainties associated in the modeling and simulation procedure of PBA, and third uncertainties originated from simplistic approach and methods utilized in the conventional procedure of PBA of the structures. Legitimacy of the scaling of ground motions is studied using the response of several simple nonlinear systems to amplitude scaled ground motions suites. Bias in the response obtained compared to unscaled records for both as recorded and synthetic ground motions. Results from this section of the research show the amount of the bias is considerable and can significantly affect the outcome of PBA. The origin of the bias is investigated and consequently a new metric is proposed to predict the bias induced by ground motion scaling without nonlinear analysis. Results demonstrate that utilizing the predictor as a scaling parameter can significantly reduce the bias for various nonlinear structures. Therefore utilizing the new metric as the intensity measuring parameter of the ground motions is recommended in PBA. To address the uncertainties associated in the modeling and simulation, MSSS concrete girder bridge class were selected due to the frequency of the construction in USCS region and lack of seismic detailing. A large scale parameters screening study is performed using Placket-Burman experimental design that considers a more complete group of parameters to decrease the computational expense of probabilistic study of the structure's seismic response. Fragility analysis for MSSS bridge is performed and the effect of removing the lesser important parameters the probabilistic demand model was investigated. This study reveals parameters reduction based on screening study techniques can be utilized to increase efficiency in fragility analysis procedure without compromising the accuracy of the outcome. The results from this study also provides more direct information on parameter reduction for PBA as well as provide insight into where future investments into higher fidelity finite element and constitutive models should be targeted. Conventional simplistic PBA approach does not account for the fundamental correlation between demand and capacity models. A more comprehensive PBA approach is presented and fragility analysis is performed with implementation of a new formulation in the component fragility analysis for MSSS bridge class and the outcome is compared with the one from conventional procedure. The results shows the correlation between demand and capacity affects the outcome of PBA and the fragility functions variation is not negligible. Therefore using the presented approach is necessary when accuracy is needed.
53

Seismic Performance Comparison of a Fixed-Base Versus a Base-Isolated Office Building

Marrs, Nicholas Reidar 01 June 2013 (has links) (PDF)
The topic of this thesis is base isolation. The purpose of this thesis is to offer a relative understanding of the seismic performance enhancements that a typical 12-story steel office building can achieve through the implementation of base isolation technology. To reach this understanding, the structures of a fixed-base office building and a base-isolated office building of similar size and layout are designed, their seismic performance is compared, and a cost-benefit analysis is completed. The base isolation system that is utilized is composed of Triple Friction Pendulum (TFP) bearings. The work of this thesis is divided into four phases. First, in the building selection phase, the structural systems (SMF and SCBF), layout, location (San Diego, CA), and design parameters of the buildings are selected. Then, in the design phase, each structure is designed using modal response spectrum analysis in ETABS. In the analysis phase, nonlinear time history analyses at DBE and MCE levels are conducted in PERFORM-3D to obtain the related floor accelerations and interstory drifts. Finally, in the performance assessment phase, probable damage costs are computed using fragility curves and FEMA P-58 methodology in PACT. Damage costs are computed for each building and seismic demand level and the results are compared.
54

Seismic Performance Analysis of Fill Dams Using Velocity Based Space-Time Finite Element Method / 速度型Space-Time有限要素法によるフィルダム耐震性能照査

Sakai, Kotaro 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(農学) / 甲第23239号 / 農博第2446号 / 新制||農||1083(附属図書館) / 学位論文||R3||N5329(農学部図書室) / 京都大学大学院農学研究科地域環境科学専攻 / (主査)教授 村上 章, 教授 藤原 正幸, 教授 渦岡 良介 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DGAM
55

SYSTEM-LEVEL SEISMIC PERFORMANCE OF CONCENTRICALLY BRACED FRAMES WITH REPLACEABLE BRACE MODULES

Mohsenzadeh, Vahid January 2020 (has links)
Concentrically braced frames with replaceable brace modules (RBMs) have the potential of improving the constructability of braced frames, mitigating the structural damage during earthquakes, and minimizing the time of post-earthquake repairs. To fill the gaps between the component-level performance of RBMs and system-level behaviour of SCBFs with RBMs, this thesis focused on the overall system-level seismic performance of SCBFs with RBMs in three steps. Firstly, the effects of beam-column connection fixity on the behaviour of three SCBFs were investigated to determine what level of fixity, if any, is required to ensure adequate collapse capacity of an SCBF. Secondly, the effects of column design parameters on braced frame seismic performance were investigated, where two different brace-to-frame connections were considered: 1) conventional gusset plate connection and 2) the newly proposed connection detail with RBMs. Detailed numerical modelling was undertaken to develop improved provisions for designing columns in SCBFs. Finally, a large-scale experimental program was conducted to evaluate the seismic performance of braced frames with initial and replaced RBMs where realistic boundary conditions were provided. Three different beam-column connections that can be used in SCBFs with RBMs were designed and tested. Based on the current work, the recently proposed concept of replaceable brace modules, accompanied by the recommended methods for designing columns and detailing beam-column connections, appears to be a promising approach. The fabrication and installation are simpler, the seismic performance is similar to that of SCBFs with currently accepted connection detailing, and the approach can increase the post-earthquake reparability of steel concentrically braced frames. / Dissertation / Doctor of Philosophy (PhD)
56

Αποτίμηση σεισμικής συμπεριφοράς και ενίσχυση μη-κανονικών σε κάτοψη κατασκευών οπλισμένου σκυροδέματος / Seismic performance assessment and strengthening of asymmetric in plan reinforced concrete structures

Κοσμόπουλος, Αντώνης 24 June 2007 (has links)
Η παρούσα διατριβή πραγματεύεται την αποτίμηση της σεισμικής συμπεριφοράς και την ενίσχυση μη-κανονικών σε κάτοψη κτιρίων οπλισμένου σκυροδέματος. Σε μια έντονα σεισμογενή περιοχή όπως η Ελλάδα, η ύπαρξη πολύ μεγάλου ποσοστού (περί το 70%) κατασκευών που δεν διαθέτουν την ασφάλεια έναντι του σεισμού που απαιτούν οι σημερινοί κανονισμοί, αποτελεί μεγάλο πρόβλημα. Επιπλέον, πέραν της έλλειψης αντισεισμικού σχεδιασμού τους, η δομική μορφολογία της πλειοψηφίας των κατασκευών αυτών ευνοεί την ανάπτυξη στρεπτικής απόκρισης κατά το σεισμό, καθιστώντας ακόμα πιο δυσμενή την κατάσταση. Πέραν των τεχνικών και οικονομικών δυσχερειών που παρουσιάζει η ενίσχυση των κατασκευών αυτών, έως τώρα, και πριν τη θεσμοθέτηση στην Ελλάδα του αντίστοιχου μέρους του Ευρωκώδικα 8 (Μέρος 3) ή του Κανονισμού Επεμβάσεων (ΚΑΝΕΠΕ), η ενίσχυση είχε κυρίως εμπειρικό χαρακτήρα. Στη διατριβή αυτή προτείνονται υπολογιστικά εργαλεία και μέθοδοι για τη λεπτομερή αποτίμηση της σεισμικής συμπεριφοράς της προβληματικής αυτής κατηγορίας κατασκευών με στόχο την κατανόηση της απόκρισής τους κατά το σεισμό αλλά και τον προσδιορισμό των «αδύνατων σημείων» τους, έτσι ώστε η ενίσχυση να είναι προσανατολισμένη ακριβώς εκεί, κάτι που είναι ορθολογικότερο όχι μόνο επιστημονικά αλλά και από άποψη κόστους. Ως αντικείμενο μελέτης και εφαρμογής των μεθόδων και διαδικασιών που προτείνονται σε αυτή τη διατριβή χρησιμοποιούνται τέσσερα πραγματικά κτίρια, δύο από τα οποία προϋπήρχαν ενώ τα υπόλοιπα κατασκευάστηκαν με σκοπό τη διεξαγωγή πειραματικών δοκιμών με την ψευδοδυναμική μέθοδο. Τα υφιστάμενα κτίρια είναι η τετραώροφη πολυκατοικία επί των οδών Πίνδου και Γ. Παπανδρέου στη Νέα Φιλαδέλφεια Αττικής η οποία κατέρρευσε κατά τον σεισμό της Αθήνας το 1999, και το Δημοτικό Θέατρο Αργοστολίου «Ο Κέφαλος». Από τα δύο κτίρια που κατασκευάστηκαν εξ’ αρχής, το πρώτο είναι τριώροφο σε φυσική κλίμακα και κατασκευάστηκε για να δοκιμαστεί ψευδο-δυναμικά στο Κοινό Κέντρο Έρευνας της Ευρωπαϊκής Ένωσης στην Ispra της Ιταλίας, και το δεύτερο είναι διώροφο σε κλίμακα 1:0.75 και κατασκευάστηκε για να δοκιμαστεί ψευδο-δυναμικά στο Εργαστήριο Κατασκευών του Τμήματος Πολιτικών Μηχανικών του Πανεπιστημίου Πατρών. Και τα τέσσερα κτίρια είναι χαρακτηριστικά της μελετητικής και κατασκευαστικής πρακτικής που ίσχυε στην Ελλάδα αλλά και στην ευρύτερη περιοχή της νότιας Ευρώπης τη δεκαετία του 1970. Στο πρώτο Κεφάλαιο της διατριβής γίνεται αναφορά στο πρόβλημα της ύπαρξης στη χώρα μας μεγάλου ποσοστού υφισταμένων κατασκευών χωρίς επαρκή ή και στοιχειώδη αντισεισμικό σχεδιασμό. Ακολουθεί μια σύντομη ιστορική αναδρομή στην εξέλιξη και βελτίωση των Ελληνικών αντισεισμικών κανονισμών, καθώς και μια αναφορά στις πρακτικές δυσχέρειες της σεισμικής αποτίμησης και ενίσχυσης. Στο δεύτερο Κεφάλαιο γίνεται αναφορά στους στόχους αποτίμησης της φέρουσας ικανότητας και της ενίσχυσης κατά τους σύγχρονους κανονισμούς (Ευρωκώδικα 8 – Μέρος 3 και ΚΑΝΕΠΕ), τις στάθμες επιτελεστικότητας κατά το σεισμό που αυτοί εισάγουν, καθώς και στην ανίσωση ασφαλείας που ισχύει κατά περίπτωση για τη σεισμική «ζήτηση» και τη σεισμική «ικανότητα», με αναλυτική παρουσίαση των κατά περίπτωση συντελεστών ασφαλείας που ισχύουν για τα υλικά, τις μεθόδους ανάλυσης, την αξιοπιστία των διαθέσιμων δεδομένων κλπ. Στο τρίτο Κεφάλαιο παρουσιάζεται συνοπτικά το υπολογιστικό εργαλείο ANSRuop που αναπτύχθηκε στα πλαίσια της παρούσας διατριβής και χρησιμοποιήθηκε για τη διεξαγωγή όλων των αναλύσεων, γραμμικών ελαστικών, ιδιομορφικών, δυναμικών φασματικών, μη-γραμμικών στατικών (pushover) και μη-γραμμικών αναλύσεων χρονοϊστορίας. Στη συνέχεια παρατίθενται και αναλύονται οι μαθηματικές σχέσεις που χρησιμοποιούνται για την προσομοίωση των μελών οπλισμένου σκυροδέματος και την ποσοτικοποίηση των μεγεθών έντασης και παραμόρφωσης που υπεισέρχονται στην διαδικασία της σεισμικής αποτίμησης και ενίσχυσης. Στο τέταρτο Κεφάλαιο γίνεται εφαρμογή των μεθόδων αποτίμησης για τις τέσσερις κατασκευές με τις οποίες ασχολείται η διατριβή. Αυτές περιλαμβάνουν τη διερεύνηση των στατικών εκκεντροτήτων των κατασκευών (οι οποίες δίνουν ένδειξη για την ενδεχόμενη ανάπτυξη δυσμενούς στρεπτικής απόκρισης κατά το σεισμό η οποία οδηγεί σε περαιτέρω αύξηση των παραμορφώσεων), τη διερεύνηση των ιδιομορφικών χαρακτηριστικών τους, (ιδιοπεριόδων και ιδιομορφών), τη διεξαγωγή μη-γραμμικών στατικών αναλύσεων στο χώρο (pushover) για μια πρώτη εκτίμηση της συμπεριφοράς και των αδύνατων σημείων των κατασκευών, και τη διεξαγωγή δεσμών μη-γραμμικών αναλύσεων χρονοϊστορίας για την ακριβή κατανόηση της σεισμικής απόκρισης και το λεπτομερή προσδιορισμό των αδύνατων αυτών σημείων. Στο πέμπτο Κεφάλαιο προτείνονται τρόποι ενίσχυσης για τις τρεις από τις κατασκευές του Κεφαλαίου 4, και διερευνάται η αποδοτικότητα και η επάρκεια της ενίσχυσης με χρήση των υπολογιστικών μεθόδων του Κεφαλαίου 4, ενώ εξετάζεται και το κατά πόσο ο τρόπος της ενίσχυσης πέτυχε το στόχο της μείωσης της στατικής εκκεντρότητας και συνεπώς οδήγησε σε μερική αποτροπή της στρεπτικής απόκρισης. Στο έκτο Κεφάλαιο γίνεται διερεύνηση της σχέσης ανάμεσα στις ανελαστικές και τις ελαστικές παραμορφώσεις που προκύπτουν υπολογιστικά από τη διεξαγωγή μη-γραμμικών αναλύσεων χρονοϊστορίας και ελαστικών αναλύσεων (ισοδύναμης στατικής ή δυναμικής φασματικής) αντίστοιχα, ειδικά για την περίπτωση των μη-κανονικών κτιρίων με τα οποία ασχολείται η παρούσα διατριβή. Η σύγκριση αυτή είναι σημαντική, δεδομένου ότι σε πολύ μεγάλο βαθμό στην πράξη για τον προσδιορισμό των (ανελαστικών) παραμορφώσεων οι κανονισμοί επιτρέπουν χρήση ελαστικών αναλύσεων. Στο έβδομο Κεφάλαιο εισάγεται ένα απλό υπολογιστικό προσομοίωμα, με ένα κατακόρυφο στοιχείο ανά όροφο, με σκοπό την αναπαραγωγή της δυναμικής απόκρισης στο χώρο πλήρων, μη-κανονικών σε κάτοψη κατασκευών, αλλά και την περαιτέρω διερεύνηση της επιρροής της στατικής εκκεντρότητας στην απόκριση. Στο όγδοο Κεφάλαιο αξιοποιούνται τα αποτελέσματα των δεσμών μη-γραμμικών αναλύσεων χρονοϊστορίας για μία από τις κατασκευές της διατριβής, καθώς και τα αποτελέσματα από αναλύσεις σεισμικής επικινδυνότητας για τον Ελλαδικό χώρο που έγιναν στα πλαίσια της διατριβής, για την σεισμική αποτίμηση σε πιθανοτικούς όρους, και συγκεκριμένα με εφαρμογή της μεθοδολογίας Cornell που δίνει το μέσο ετήσιο ρυθμό υπέρβασης μιας συγκεκριμένης Οριακής Κατάστασης σε ένα μέλος ή περιοχή μέλους ενός δομήματος. Τέλος, στο ένατο Κεφάλαιο παρουσιάζονται τα γενικά συμπεράσματα που προκύπτουν από την εφαρμογή των μεθόδων και διαδικασιών σεισμικής αποτίμησης και ενίσχυσης μη-κανονικών σε κάτοψη κατασκευών οπλισμένου σκυροδέματος. / This thesis deals with the problem of seismic performance assessment and strengthening of existing, asymmetric in-plan reinforced concrete buildings. In a highly seismic region such as Greece, the fact that the majority (over 70%) of existing buildings are not designed against earthquake loads constitutes a serious problem. Furthermore, the structural configuration of these buildings often is such that promotes torsional response during the earthquake, thus worsening their already poor performance. In addition to the technical and financial difficulties inherent in the seismic strengthening procedures, until now (i.e. before Eurocode 8 – Part 3 and the Greek Code for Structural Interventions - KANEPE) there was a lack of a framework of codes addressing the issues of the assessment of seismic performance and strengthening of existing buildings. This dissertation suggests computational tools and procedures for a detailed assessment of the seismic performance of this problematic category of structures, aiming to the understanding of their response and the identification of their “weak points” so that the strengthening procedure can focus exactly there. Four real buildings are used as specimens for this study, two of which were designed and constructed to be tested pseudo-dynamically. The four buildings are: the four-story apartment building that collapsed during the 1999 Athens earthquake; the municipal theater of Argostoli “O KEFALOS”; the three-story building that was constructed and pseudo-dynamically tested at the reaction wall facilities of the ELSA laboratory of the European Joint Research Centre in Ispra, Italy, and the two-story building that was constructed and pseudo-dynamically tested at the reaction wall facilities of the Laboratory of Structures of the Department of Civil Engineering of the University of Patras in Greece. The first Chapter of the thesis deals with the definition of the problem that is posed by the existence of a big majority of structures without adequate (or any) resistance to lateral, earthquake loads. Also present are brief references to the historical evolution of the Greek Seismic Codes, and to the practical difficulties of the assessment of seismic performance and strengthening. The second Chapter defines the targets of seismic performance assessment and strengthening according to modern Codes, looks into the Limit States that they induce, and the comparison of deformational capacity and demand, with a reference to the relevant safety factors. The third Chapter presents briefly the computational tool that was developed during the course of this PhD work, namely the computer program ANSRuop that was used to carry out all the analyses, including linear static, modal, multimodal response spectrum, nonlinear static (pushover) and nonlinear time-history analyses. Next are presented the analytical equations that are used for the modeling of reinforced concrete buildings, and the quantification of the terms of forces and deformations that are involved in the assessment and strengthening procedures. The fourth Chapter contains the application of the seismic performance assessment procedures to the four buildings of the thesis, including the identification of their static eccentricities in-plan (which give an indication or whether or not torsional response is to be expected during the earthquake, which leads to a magnification of the deformations), their dynamic characteristics (natural periods and modes of vibration), as well as the carrying out of sets of nonlinear time-history analyses aiming to the understanding of their seismic response and the detailed identification of their “weak points”. In the fifth Chapter, strengthening schemes are proposed for three of the buildings of the thesis, the efficiency and adequacy of which are investigated using the computational methods also used in the fourth Chapter. Special attention is made to whether the strengthening scheme succeeded in reducing the static eccentricities in-plan, which in turn leads to a reduction of the torsional response. The sixth Chapter investigates the relation between inelastic and elastic deformations, which are the results of nonlinear time-history analyses and elastic analyses (equivalent static or multimodal response spectrum), respectively. The seventh Chapter introduces a simple computational model with one vertical element per floor, which aims to the replication of the three-dimensional dynamic response of complex, asymmetric in-plan structures, but also to the further investigation of the effect of static eccentricity to the response. The eighth Chapter utilizes the results of the sets of the nonlinear time-history analyses for one of the buildings of the thesis, as well as the results of seismic risk analyses, which were also conducted within the framework of this PhD work, with an aim to the expression of the assessment of seismic performance in probabilistic terms (specifically with the application of a methodology proposed by Cornell, which leads to the mean annual rate of exceedance of a specific limit state at a structural member). Finally, the ninth Chapter presents the general conclusions that can be extracted from the application of the methods and procedures of seismic performance assessment and strengthening of existing, asymmetric in-plan reinforced concrete buildings.
57

Seismic performance evaluations and analyses for composite moment frames with smart SMA PR-CFT connections

Hu, Jong Wan 01 April 2008 (has links)
This thesis investigates the performance of composite frame structures with smart partially-restrained (PR) concrete filled tube (CFT) column connections through simplified 2D and advanced 3D computational simulations. It also provides a design methodology for new types of innovative connections based on achieving a beam hinging mechanism. These types of connections intend to utilize the recentering properties of super-elastic SMA tension bars, the energy dissipation capacity of low-carbon steel bars, and the robustness of CFT columns. In the first part of this study, three different PR-CFT connection prototypes were designed based on a hierarchy of strength models for each connection component. Numerical simulations with refined three dimensional (3D) solid elements were conducted on full scale PR-CFT connection models in order to verify the strength models and evaluate the system performance under static loading. Based on system information obtained from these analyses, simplified connection models were formulated by replacing the individual connection components with spring elements and condensing their contributions. Connection behavior under cyclic loads was extrapolated and then compared with the monotonic behavior. In the second part of this study, the application of these connections to low-rise composite frames was illustrated by designing both 2D and 3D, 4 and 6 story buildings for the Los Angeles region. A total of 36 frames were studied. Pushover curves plotted as the normalized shear force versus inter story drift ratio (ISDR) showed significant transition points: elastic range or proportional limit, full yielding of the cross-section, strength hardening, ultimate strength, and strength degradation or stability limit. Based on the transition points in the monotonic pushover curves, three performance levels were defined: Design Point, Yield Point, and Ultimate Point. All frames were stable up to the yield point level. For all fames, after reaching the ultimate point, plastic rotation increased significantly and concentrated on the lower levels. These observations were quantified through the use of elastic strength ratios and inelastic curvature ductility ratios. The composite frames showed superior performance over traditional welded ones in terms of ductility and stability, and validated the premises of this research.
58

Influencia de las irregularidades de piso blando y torsión en el desempeño sísmico mediante el Análisis Estático No Lineal de una vivienda multifamiliar de concreto armado ubicado en la ciudad de Lima - sistema dual de 10 pisos diseñado según el Reglamento Nacional de Edificaciones / Influence of Soft Floor and Torsion Irregularities on Seismic Performance Through Nonlinear Static Analysis of A Reinforced Concrete Multifamily House - Dual 10-Story System Designed According To The National Building Regulations

Blas Calhua, Oriol Eliseo, Lagos Carbajal, Wilmer Antony 25 May 2021 (has links)
En la presente tesis se determina la influencia de las irregularidades de piso blando y torsión mediante el desempeño sísmico de ocho edificios de diez pisos - Sistema Dual, ubicados en la ciudad de Lima (Zona 4). Se plantea cuatro modelos por cada irregularidad de estudio, donde el primer modelo es una estructura regular y los tres modelos restantes presentan irregularidades, esto con la finalidad de determinar la influencia de las irregularidades en el desempeño sísmico frente a diferentes niveles de amenaza sísmica (Sismo frecuente, Ocasional, Raro y Muy raro). Todos los modelos se definieron en función de los parámetros y criterios de la Norma de Diseño Sismo Resistente E.030 (2018). Luego se realiza el Análisis Sísmico Estático y Dinámico, para verificar que los modelos cumplen con el diseño sísmico. Efectuado el Análisis Sísmico se prosigue a diseñar los elementos estructurales, tales como: vigas, columnas y muros de concreto armado, cuyo resultado del diseño se refleja en los planos estructurales. Cabe recalcar que los planos tienen el mismo diseño estructural de acuerdo a la norma E.060. Seguidamente se realiza el Análisis Estático No Lineal (AENL) – Pushover, haciendo uso de las recomendaciones del ASCE/SEI 41-13 con la finalidad de determinar la curva de capacidad de los ocho modelos de estudio y obtener los mecanismos de formación de rótulas plásticas en los elementos estructurales. El punto de desempeño de los ocho modelos de estudio se obtiene mediante el Método del Espectro de Capacidad (ATC-40 y FEMA 440), donde la demanda sísmica se define a través del espectro de diseño de la norma E.030 (2018). Finalmente, se realiza la evaluación de las irregularidades de piso blando y torsión en el desempeño sísmico de acuerdo con los objetivos de desempeño según Comité Visión 2000 y el ATC-40, para el caso de estudio de irregularidad de piso blando, la curva de capacidad tiene una disminución en la cortante basal y un aumento en el desplazamiento a medida que la irregularidad aumenta en ambas direcciones. Mientras que, en el caso de la irregularidad de torsión, la curva de capacidad tiene una reducción de la cortante basal y desplazamiento a medida que la irregularidad aumenta en ambas direcciones. En todos los casos de estudio de los modelos regulares e irregulares, cumple con la evaluación del desempeño sísmico para los distintos niveles de amenaza sísmica. / In this thesis, the influence of soft floor and torsional irregularities is determined through the seismic performance of eight ten-story buildings - Dual System, located in the city of Lima (Zone 4). Four models are proposed for each irregularity under study, where the first model is a regular structure and the remaining three models present irregularities, with the purpose of determining the influence of irregularities on the seismic performance against different levels of seismic hazard (Frequent, Occasional, Rare and Very Rare earthquakes). All models were defined based on the parameters and criteria of the Earthquake Resistant Design Standard E.030 (2018). Then, the Static and Dynamic Seismic Analysis is performed to verify that the models comply with the seismic design. Once the Seismic Analysis is performed, the structural elements are designed, such as: beams, columns and reinforced concrete walls, whose design result is reflected in the structural drawings. It should be noted that the plans have the same structural design according to the E.060 standard. Next, the Non-Linear Static Analysis (NLSA) - Pushover is performed, making use of the recommendations of ASCE/SEI 41-13 in order to determine the capacity curve of the eight study models and to obtain the mechanisms of formation of plastic hinges in the structural elements. The performance point of the eight study models is obtained through the Capacity Spectrum Method (ATC-40 and FEMA 440), where the seismic demand is defined through the design spectrum of the E.030 (2018) standard. Finally, the evaluation of soft-story and torsional irregularities on seismic performance is performed according to the performance objectives according to Vision 2000 Committee and ATC-40, for the soft-story irregularity study case, the capacity curve has a decrease in basal shear and an increase in displacement as the irregularity increases in both directions. While, in the case of torsional irregularity, the capacity curve has a decrease in basal shear and displacement as the irregularity increases in both directions. In all the case studies of the regular and irregular models, it complies with the seismic performance evaluation for the different seismic hazard levels. / Tesis
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Evaluación del Desempeño Sísmico de una Nave Industrial de Acero para el sector minero utilizando el ATC-40 / Evaluation of the seismic performance of a mining steel building according to ATC-40

Guevara Alarcón, Aldo Fernando 05 November 2020 (has links)
El trabajo de investigación se ha denominado “Evaluación del desempeño sísmico de una nave industrial de acero para el sector minero utilizando el ATC-40”, tiene como propósito determinar el comportamiento sísmico de la nave industrial de acero para el sector minero mediante el código ATC-40. La aplicación de análisis estático no lineal como Pushover y Pushover Modal al modelo de cálculo de estructuras existentes ayuda a determinar el grado de daño y el desempeño sísmico. De esta manera, se aplicó satisfactoriamente el análisis estático no lineal al modelo de una estructura existente mediante el uso del software SAP2000, y a través de datos y gráficos proporcionados por el programa, se conoció el nivel de daño para la nave industrial de acero sometida a grandes solicitaciones sísmicas. El desarrollo de esta tesis se divide en siete capítulos: El primer capítulo es de introducción e importancia. La segunda comprende de las generalidades, objetivos generales y específicos del proyecto de tesis; en el tercero se desarrolla el marco teórico para el análisis Pushover; en el cuarto se muestra el análisis estático lineal y no lineal; el quinto comprende el diseño por el método LRFD y su validación; el sexto presenta el criterio de desempeño sísmico usando el código ATC-40; en el séptimo se muestra el análisis de resultados; el octavo muestra las conclusiones y recomendaciones. Del análisis presentado, se concluye que mediante el análisis Pushover se pudo determinar el nivel de desempeño deseado asegurando continuidad para la producción del mineral, de lo cual se puede garantizar que la estructura va tener un comportamiento aceptable ante los 3 niveles de peligro sísmico y no se verá afectada su producción de mineral. / The present research project is entitled "Evaluation of the seismic performance of a mining steel building according to ATC-40" and has the purpose of determining the seismic performance of a mining building defined in the technical report ATC-40. The application of a static nonlinear analysis to the computational model of an existing structure can determine the level of damage and the expected seismic performance. Accordingly, the nonlinear static analysis was successfully applied to the model of an existing structure using SAP2000 software, and through data and graphics provided by the program, the level of damage in the industrial building subjected to great seismic actions was determined. This thesis is divided into seven chapters: the first chapter cover the introduction and the importance of the thesis. The second chapter include the generalities, general objectives and specific objectives of the thesis project; the third reviews the Pushover analysis theoretical framework; the fourth shows the linear and nonlinear static analyses; the fifth includes the design by the LRFD method and its validation; the sixth presents the criteria of seismic performance using the ATC-40 method; the seventh shows the analysis of results; the eighth shows the conclusions and recommendations. From the presented analysis, it is concluded that it was possible to achieve the level of performance desired ensuring continuous ore production, and with this, it can be guaranteed that the structure will have an acceptable behavior for the 3 levels of seismic hazard and that the ore production will not be affected. / Tesis
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Desempeño sísmico de una edificación de concreto armado dual mediante el análisis no lineal en el tiempo ubicado en el distrito de Lince, departamento de Lima-Perú / Seismic performance of a reinforced concrete building through nonlinear análisis over time

Ojeda Barrionuevo, Jean Paul, López Pizarro, Juan Américo 12 February 2021 (has links)
El tema de esta investigación aborda el desempeño sismorresistente de un edificio en Lima aplicando el análisis dinámico no lineal “Tiempo historia”. Por ello, la hipótesis plantea que el desempeño sísmico de un edificio destinado a vivienda en la ciudad de Lima debido a un sismo moderado y severo, cumple con lo indicado en la Norma Peruana Sismorresistente E-030 respecto a sus objetivos del no daño estructural y el no colapso respectivamente, si los puntos de desempeño obtenidos al comparar la curva de Capacidad con la curva de Demanda de la Norma E-030 se encuentran dentro del rango de desempeño establecido según el código de la Agencia Federal para el Manejo de Emergencias (FEMA). Consecuentemente, la investigación está dividida en 5 capítulos. En el primero, se presenta la descripción de la estructura a analizar, que abarca sus características arquitectónicas y estructurales. En el segundo, se expone una serie de conceptos fundamentales plasmados en el marco teórico, para entender el desempeño sísmico y todo lo relacionado con este análisis. En el tercero y cuarto, se realiza la evaluación del desempeño sismorresistente aplicando el Análisis Dinámico No lineal Tiempo Historia. Finalmente, se verificará si el desempeño sismorresistente de un edificio de albañilería confinada en la ciudad de Lima cumple o no con los objetivos de la Norma Peruana Sismorresistente E-030 2019. / The subject of this research deals with the seismic performance of a building in Lima applying the non-linear dynamic analysis "Time History". Therefore, the hypothesis states that the seismic performance of a building intended for housing in the city of Lima due to a moderate and severe earthquake, complies with the provisions of the Peruvian Seismic E-030 Standard regarding its objectives of structural and non-structural damage. the non-collapse respectively, if the performance points obtained when comparing the Capacity curve with the Demand curve of the E-030 Standard are within the performance range established according to the code of the Federal Emergency Management Agency (FEMA). Consequently, the investigation is divided into 5 chapters. In the first one, the description of the structure to be analyzed is presented, which covers its architectural and structural characteristics. In the second, a series of fundamental concepts embodied in the theoretical framework is exposed to understand the seismic performance and everything related to this analysis. In the third and fourth, the evaluation of the seismic performance is performed applying the dynamic nonlinear analysis Time History. Finally, it will be verified if the seismic performance of a reinforced concrete building in the city of Lima complies or not with the objectives of the Peruvian Seismic Standard E-030 2019. / Tesis

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