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Parameterized Seismic Reliability Assessment and Life-Cycle Analysis of Aging Highway BridgesGhosh, Jayadipta 16 September 2013 (has links)
The highway bridge infrastructure system within the United States is rapidly deteriorating and a significant percentage of these bridges are approaching the end of their useful service life. Deterioration mechanisms affect the load resisting capacity of critical structural components and render aging highway bridges more vulnerable to earthquakes compared to pristine structures. While past literature has traditionally neglected the simultaneous consideration of seismic and aging threats to highway bridges, a joint fragility assessment framework is needed to evaluate the impact of deterioration mechanisms on bridge vulnerability during earthquakes. This research aims to offer an efficient methodology for accurate estimation of the seismic fragility of aging highway bridges. In addition to aging, which is a predominant threat that affects lifetime seismic reliability, other stressors such as repeated seismic events or simultaneous presence of truck traffic are also incorporated in the seismic fragility analysis.
The impact of deterioration mechanisms on bridge component responses are assessed for a range of exposure conditions following the nonlinear dynamic analysis of three-dimensional high-fidelity finite element aging bridge models. Subsequently, time-dependent fragility curves are developed at the bridge component and system level to assess the probability of structural damage given the earthquake intensity. In addition to highlighting the importance of accounting for deterioration mechanisms, these time-evolving fragility curves are used within an improved seismic loss estimation methodology to aid in efficient channeling of monetary resources for structural retrofit or seismic upgrade. Further, statistical learning methods are employed to derive flexible parameterized fragility models conditioned on earthquake hazard intensity, bridge design parameters, and deterioration affected structural parameters to provide significant improvements over traditional fragility models and aid in efficient estimation of aging bridge vulnerabilities. In order to facilitate bridge management decision making, a methodology is presented to demonstrate the applicability of the proposed multi-dimensional fragility models to estimate the in-situ aging bridge reliabilities with field-measurement data across a transportation network. Finally, this research proposes frameworks to offer guidance to risk analysts regarding the importance of accounting for supplementary threats stemming from multiple seismic shocks along the service life of the bridge structures and the presence of truck traffic atop the bridge deck during earthquake events.
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Seismic Fragility Assessment of Steel Frames in the Central and Eastern United StatesKinali, Kursat 28 March 2007 (has links)
The Central and Eastern United States (CEUS) is a region that is characterized by low frequency-high consequence seismic events such as the New Madrid sequence of 18111812. The infrequent nature of earthquakes in the region has led to a perception that the seismic risk in the area is low, and the current building stock reflects this perception. The majority of steel-framed buildings in the CEUS were designed without regard to seismic loads. Such frames possess limited seismic resistance, and may pose an unacceptable risk if a large earthquake were to occur in the region. A key ingredient of building performance and seismic risk assessment is the fragility, a term that describes the probability of failure to meet a performance objective as a function of demand on the system. The effects of uncertainties on building seismic performance can be displayed by a seismic fragility relationship. This fragility can be used in a conditional scenario-based seismic risk assessment or can be integrated with seismic hazard to obtain an estimate of annual or lifetime risk. The seismic fragility analyses in this study focus on steel frames that are typical of building construction in regions of infrequent seismicity; such frames have received little attention to date in building seismic risk assessment. Current steel building stock in Shelby Co., TN has been represented by five code-compliant model frames with different lateral force-resisting systems, i.e., braced-frames, partially-restrained moment frames and a rigid moment frame. The performance of model frames under certain hazard levels was assessed using fragility curves. Different rehabilitation methods were discussed and applied. Results indicate that PR frames behave better than expected and rehabilitated frames perform quite well even under severe earthquakes.
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Fragility Based Assessment Of LowOzun, Ahsen 01 May 2007 (has links) (PDF)
In this study, the seismic fragility assessment of low-rise and mid-rise reinforced concrete frame buildings which constitute approximately 75 % of the total building stock in Turkey is investigated to quantify the earthquake risk. The inventory used in this study is selected from Dü / zce damage database which was compiled after the devastating 1999 earthquakes in the Marmara region. These buildings are not designed according to the current code regulations and the supervision in the construction phase is not adequate.
The building database is divided into sub-classes according to the height and absence of infilled walls. Each building in the database is represented by an equivalent single degree of freedom system with three structural parameters: period, strength, and post-elastic stiffness ratio. The ground motion records are selected from different parts of the world covering a wide range of characteristics. The capacity of the structure is represented for each sub-class by the limit states. Hence, a set of fragility curves for low- and mid-rise reinforced concrete structures are developed by making use of the building characteristics in the database. The generated fragility curve set is referred as &ldquo / reference&rdquo / since it forms the basis of a parametric study. A parametric study is conducted to examine the influence of post-elastic stiffness ratio, simulation and sampling techniques, sample size, limit state definition and degrading behavior on the final fragility curves. Estimated damage distribution after two consecutive major earthquakes is compared with the actual field data in order to investigate the validity of the generated fragility curves.
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Seismic performance evaluation of port container cranes allowed to upliftKosbab, Benjamin David 31 March 2010 (has links)
The seismic behavior of port container cranes has been largely ignored-by owners, operators, engineers, and code officials alike. This is despite their importance to daily port operations, where historical evidence suggests that port operational downtime following a seismic event can have a crippling effect on the affected local, regional, and national economies. Because the replacement time in the event of crane collapse can be a year or more, crane collapse has the potential to be the "critical path" for post-disaster port recovery. Since the 1960's, crane designers allowed and encouraged an uplift response from container cranes, assuming that this uplift would provide a "safety valve" for seismic loading; i.e. the structural response at the onset of uplift was assumed to be the maximum structural response. However, cranes have grown much larger and more stable such that the port industry is now beginning to question the seismic performance of their modern jumbo container cranes.
This research takes a step back, and reconsiders the effect that uplift response has on the seismic demand of portal-frame structures such as container cranes. A theoretical estimation is derived which accounts for the uplift behavior, and finds that the "safety valve" design assumption can be unconservative. The resulting portal uplift theory is verified with complex finite element models and experimental shake-table testing of a scaled example container crane. Using the verified models, fragility curves and downtime estimates are developed which characterize the risk of crane damage and operational downtime for three representative container cranes subjected to a range of earthquakes. This research demonstrates that container cranes designed using previous and current standards can significantly contribute to port seismic vulnerability. Lastly, performance-based design recommendations are provided which encourage the comparison of demand and capacity in terms of the critical portal deformation, using the derived portal uplift theory to estimate seismic deformation demand.
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Effects of aging and remodeling on bone microdamage formationWang, Jason Lee 18 November 2010 (has links)
Skeletal fragility is characterized by low bone mass, negative changes in bone microarchitecture, and compromised tissue matrix properties, including accumulation of microdamage. Microdamage accumulates in vivo from daily physiological loading and is targeted for repair through a normal remodeling process, thus preventing microcrack growth and potential fracture. However, impaired remodeling is associated with aging and osteoporosis, resulting in an increased accumulation of microdamage which contributes to reduced bone mechanical properties. The current clinical method for assessing increased risk of fracture involves measuring bone mineral density (BMD) of the hip and spine, locations of trabecular bone where high rates of remodeling occur. The bisphosphonate alendronate (ALN) reduces clinical risk for fracture by significantly increasing BMD, but studies have shown a concomitant reduction in intrinsic properties that may be the underlying cause for recent reports of spontaneous fractures with long-term alendronate use. Another anti-resorptive agent called raloxifene (RAL) is a selective estrogen receptor modulator (SERM) and has been shown to modestly improve BMD while decreasing fracture risk to a similar degree as alendronate. The combination of RAL and ALN as a treatment for osteoporosis may provide the benefits of each drug without the negative effects of ALN.
Therefore, the overall goal of this thesis was to address the effects of aging and anti-resorptive agents on the properties of bone through the formation of microdamage. Assessment of age-related effects on bone was conducted through quantification of microdamage progression. It was found that old bone results in greater incidences of microdamage progression, reflecting a compromised tissue matrix with reduced resistance to crack growth. Effects of combination treatment with RAL and ALN were evaluated through biomechanical testing, micro-CT imaging, and microdamage quantification. Results showed improved trabecular bone volume and ultimate load with positive effects on trabecular architecture. Combination treatment reduced the proportion of microdamage that may lead to catastrophic fracture, indicating an improvement in the local tissue matrix properties.
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Seismic vulnerability assessment of wharf structuresShafieezadeh, Abdollah 08 July 2011 (has links)
Serving as critical gateways for international trade, seaports are pivotal elements in transportation networks. Any disruption in the activities of port infrastructures may lead to significant losses from secondary economic effects, and can hamper the response and recovery efforts following a natural disaster. Particularly poignant examples which revealed the significance of port operations were the 1995 Kobe earthquake and 2010 Haiti earthquake in which liquefaction and lateral spreading of embankments imposed severe damage to both structural and non-structural components of ports.
Since container wharf structures are responsible for loading and unloading of cargo, it is essential to understand the performance of these structures during earthquakes. Although previous studies have provided insight into some aspects of the seismic response of wharves, limitations in the modeling of wharf structures and the surrounding soil media have constrained the understanding of various features of the wharf response. This research provides new insights into the seismic behavior of wharves by using new and advanced structure and soil modeling procedures to carry out two and three-dimensional seismic analyses of a pile-supported marginal wharf structure in liquefiable soils. Furthermore, this research investigates the interaction between cranes and wharves and closely assesses the role of wharf-crane interaction on the response of each of these systems. For this purpose, the specific effect of wharf-crane interaction is studied by incorporating advanced models of the crane with sliding/uplift base conditions. To reduce the computational time required for three-dimensional nonlinear dynamic analysis of the wharf in order to be applicable for probabilistic seismic demand analysis, a simplified wharf model and an analysis technique are introduced and verified. In the next step probabilistic seismic demand models (PSDMs) are generated by imposing the wharf models to a suit of ground deformations of the soil embankment and pore water pressure generated for this study through free-field analysis. Convolving PSDMs and the limit states, a set of fragility curves are developed for critical wharf components whose damage induces a disruption in the normal operation of ports. The developed fragility curves provide decision makers with essential tools for maximizing investment in wharf retrofit and fill a major gap in seismic risk assessment of seaports which can be used to assess the regional impact of the damage to wharves during a natural hazard event.
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Seismic performance of plane moment resisting frames with concrete filled steel tube columns and steel I beams / Σεισμική διερεύνηση επίπεδων καμπτικών πλαισίων με υποστηλώματα από χαλύβδινες κοιλοδοκούς γεμισμένες με σκυρόδεμα και με μεταλλικές δοκούς τύπου ΙΣκαλωμένος, Κωνσταντίνος 15 April 2015 (has links)
The purpose of this research is to investigate the seismic behavior of plane moment resisting frames (MRFs) consisting of concrete filled steel tube (CFT) columns and steel I beams through targeted studies utilizing advanced computational methodologies calibrated on the basis of existing experimental results and to propose a preliminary performance-based seismic design method for this kind of frames.
A computational study is conducted first to investigate the nonlinear cyclic response of square concrete-filled steel tubes (CFT) in bending and compression. An accurate nonlinear finite element model is created and its validity is established by comparing its results with those of existing experiments. Using this finite element model, extensive parametric studies are performed to provide information on the hysteretic and deteriorating behavior of CFT columns. Thus, on the basis of this computational study, three simple yet sufficiently accurate concentrated plasticity hysteretic models for simulating the cyclic behavior of square concrete-filled steel tube (CFT) columns, are developed.
The seismic behavior of plane MRFs consisting of I steel beams and CFT columns is investigated next. More specifically, the effect of modelling details of each individual component of CFT-MRFs, such as the CFT columns, the beam-column connections, the panel zones and the steel I beams, on their seismic behavior is studied through comparisons against available experimental results. Then, fragility curves are constructed for composite frames for various levels of modelling sophistication through nonlinear time history analyses involving three typical CFT-MRFs which have been designed according to the European seismic design codes. On the basis of these fragility curves, one can select the appropriate modelling level of sophistication that can lead to the desired seismic behavior for a given seismic intensity.
The third part of this work deals with the establishment of all the necessary ingredients for this kind of composite frames to be seismically designed by the performance-based hybrid force-displacement (HFD) seismic design method, which combines the advantages of the well-known force-based and displacement-based seismic design methods. Thus, extensive parametric studies are conducted involving nonlinear dynamic analysis of 96 frames under 100 seismic motions in order to create a databank with the response quantities of interest. Based on regression analysis, simple formulae for estimating the maximum roof displacement, the maximum inter-storey drift ratio, the maximum rotation ductility along the height of the frame and the behavior factor are developed.
Comparison of the proposed design method with those adopted by current seismic design codes demonstrates that the proposed procedure seems to be more rational and controls deformation better than current seismic design codes. Nonlinear time history analyses proved the consistency of the proposed method to accurately estimate inelastic deformation demands and the tendency of the current seismic design codes to overestimate the maximum roof displacement and underestimate the maximum inter-storey drift ratio along the height of the frames. Finally, comparisons between CFT-MRFs and all steel ones reveal that the CFT-MRFs seem to have better seismic behavior than the all steel ones and seem to be more economical structures. / Ο σκοπός της παρούσας έρευνας είναι να διερευνήσει τη σεισμική συμπεριφορά επίπεδων καμπτικών πλαισίων με υποστυλώματα από τετραγωνικές χαλύβδινες κοιλοδοκούς γεμισμένες με σκυρόδεμα και με μεταλλικές δοκούς τύπου Ι και να προτείνει μία μέθοδο αντισεισμικού σχεδιασμού με βάση την επιτελεστικότητα για αυτόν τον τύπο κατασκευών.
Αρχικά, διεξάγεται μία υπολογιστική μελέτη ώστε να διερευνηθεί η μη-γραμμική ανελαστική απόκριση υπό ανακυκλιζόμενη φόρτιση και σταθερή θλίψη των τετραγωνικών σύμμικτων υποστυλωμάτων. Ένα ακριβές και προηγμένο μοντέλο πεπερασμένων στοιχείων δημιουργείται όπου η ακρίβεια των αποτελεσμάτων του ελέγχεται μέσω συγκρίσεων των αναλυτικών λύσεων με υπαρκτά πειραματικά δεδομένα. Κατόπιν, χρησιμοποιώντας αυτό το μοντέλο πεπερασμένων στοιχείων, πραγματοποιoύνται εκτενείς παραμετρικές μελέτες με σκοπό να παραχθούν πληροφορίες σχετικά με την υστερητική συμπεριφορά των σύμμικτων υποστυλωμάτων. Έτσι, στη βάση αυτής της υπολογιστικής μελέτης, τρία απλά και αρκετά ακριβή υστερητικά μοντέλα συγκεντρωμένης πλαστιμότητας αναπτύσσονται για την προσομοίωση της συμπεριφοράς σύμμικτων υποστυλωμάτων υπό ανακυκλιζόμενη φόρτιση και σταθερή θλίψη.
Έπειτα, διερευνάται η σεισμική συμπεριφορά επίπεδων καμπτικών πλαισίων με σύμμικτα υποστυλώματα και με μεταλλικές δοκούς τύπου Ι. Πιο συγκεκριμένα εξετάζεται η επίδραση της λεπτομερής μοντελοποίησης των επιμέρους δομικών στοιχείων μια κατασκευής, όπως των σύμμικτων υποστυλωμάτων, των μεταλλικών δοκών, των κόμβων διατμητικής παραμόρφωσης και των συνδέσεων, στη σεισμική συμπεριφορά των πλαισίων μέσω συγκρίσεων με υπαρκτά πειραματικά δεδομένα. Επιπλέον, διαμορφώνονται καμπύλες τρωτότητας για τρία σύμμικτα πλαίσια σχεδιασμένα με τους Ευρωπαϊκούς κανονισμούς για διάφορα επίπεδα μοντελοποίησης χρησιμοποιώντας μη-γραμμικές αναλύσεις χρονοιστορίας. Στη βάση αυτών των καμπυλών τρωτότητας, κάποιος μπορεί να επιλέξει το κατάλληλο επίπεδο πολυπλοκότητας της μοντελοποίησης των σύμμικτων πλαισίων ώστε να οδηγηθεί στην επιθυμητή συμπεριφορά για μια δεδομένη σεισμική ένταση.
Το τρίτο μέρος της παρούσας έρευνας πραγματεύεται την ανάπτυξη της διαδικασίας που απαιτείται από την Υβριδική Δυνάμεων-Μετατοπίσεων (ΥΔΜ) μέθοδο αντισεισμικού σχεδιασμού με βάση την επιτελεστικότητα, η οποία συνδυάζει τα πλεονεκτήματα της μεθόδου των δυνάμεων και της μεθόδου των μετακινήσεων, ώστε να εφαρμόζεται για τον αντισεισμικό σχεδιασμό σύμμικτων καμπτικών πλαισίων. Έτσι, πραγματοποιούνται εκτενείς παραμετρικές μελέτες περιλαμβάνοντας μη-γραμμικές δυναμικές αναλύσεις σε 96 πλαίσια υπό 100 σεισμικές καταγραφές με σκοπό τη δημιουργία τράπεζας δεδομένων με αποκρίσεις ενδιαφέροντος. Κατόπιν αναλύσεων γραμμικής παλινδρόμησης, απλές σχέσεις προτείνονται που απαιτούνται από την ΥΔΜ μέθοδο οι οποίες συνδέουν τη μέγιστη μετακίνησης κορυφής των πλαισίων με τη στοχευόμενη μέγιστη γωνιακή παραμόρφωσης των ορόφων ή την τοπική στροφική πλαστιμότητα των μελών και την απαιτούμενη συνολική πλαστιμότητας του πλαισίου με τον συντελεστή συμπεριφοράς q.
Η σύγκριση της προτεινόμενης ΥΔΜ μεθόδου αντισεισμικού σχεδιασμού με εκείνης που προτείνεται από τον Ευρωπαϊκό κανονισμό αποδεικνύει ότι η προτεινόμενη διαδικασία φαίνεται να είναι πιο ακριβής και ελέγχει καλύτερα τις παραμορφώσεις. Μη-γραμμικές αναλύσεις χρονοιστορίας δείχνουν την συνέπεια της ΥΔΜ να εκτιμά με ακρίβεια τις απαιτήσεις των ανελαστικών παραμορφώσεων στα διάφορα επίπεδα επιτελεστικότητας σε αντίθεση με την τάση του κανονισμού να υποεκτιμά τη μέγιστη γωνιακή μετακίνησης ορόφων και να υπερεκτιμά την μέγιστη μετακίνηση κορυφής. Τέλος, συγκρίσεις σύμμικτων πλαισίων με σχεδιασμένα πλαίσια εξ’ ολοκλήρου από χάλυβα σύμφωνα με την ΥΔΜ, δείχνουν ότι τα σύμμικτα πλαίσια έχουν καλύτερη σεισμική συμπεριφορά από τα μεταλλικά και φαίνεται να είναι πιο οικονομικές κατασκευές.
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Καμπύλες σεισμικής τρωτότητας γεφυρών οπλισμένου σκυροδέματοςΑσκούνη, Παρασκευή 04 December 2012 (has links)
Στην παρούσα εργασία αναπτύχθηκαν καμπύλες τρωτότητας οδικών και σιδηροδρομικών γεφυρών οπλισμένου σκυροδέματος που συναντώνται στην Ευρώπη. Οι κατηγορίες που εξετάστηκαν ήταν αυτές των κανονικών γεφυρών, με συνεχές κατάστρωμα συνδεδεμένο με τα βάθρα είτε μονολιθικά είτε μέσω ελαστομεταλλικών εφεδράνων. Άλλες παράμετροι που θεωρήθηκαν όσον αφορά στην τυπολογία των γεφυρών είναι το μήκος της γέφυρας, το ύψος των βάθρων και η διατομή τους, ο αριθμός των υποστυλωμάτων ανά βάθρο και το επίπεδο αντισεισμικού σχεδιασμού. Ο σχεδιασμός, η διαστασιολόγηση και οι λεπτομέρειες όπλισης έγιναν βάσει του Ευρωκώδικα 2 για γέφυρες που δεν υποβάλλονται σε σεισμική φόρτιση και του Ευρωκώδικας 8 για γέφυρες που σχεδιάζονται αντισεισμικά. Για την εκτίμηση στη συνέχεια των αντισεισμικών απαιτήσεων πραγματοποιήθηκε γραμμική ελαστική ανάλυση σύμφωνα με το μέρος 3 του Ευρωκώδικα 8 χρησιμοποιώντας την επιβατική δυσκαμψία των βάθρων και το ελαστικό φάσμα απόκρισης. Εν τέλει ότι οι συναρτήσεις τρωτότητας κατασκευάστηκαν έχοντας λάβει υπόψη την αβεβαιότητα του μοντέλου όσον αφορά στην σεισμική απόκριση και αντοχή, την διασπορά στην αντοχή των υλικών και τα γεωμετρικά χαρακτηριστικά και την αβεβαιότητα των φασματικών τιμών. / This study presents first a literature review of existing fragility functions for bridges and then new fragility curves that were produced for European road and railway RC bridges. Regular bridges with continuous deck, connected to the piers either monolithically or through elastomeric bearings, were studied. Other variable parameters were: bridge length, pier height and cross-section, number of columns per pier and level of seismic design. Each bridge was designed, dimensioned and detailed according to Eurocode 2 and, for bridges with seismic design, according to Eurocode 8. Linear elastic analysis was subsequently performed according to Part 3 of Eurocode 8 to estimate the seismic demand. Fragility functions were then constructed accounting for the model uncertainty for demand and capacity, the dispersion of material and geometric properties and the uncertainty of spectral values.
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Análise comparativa da fragilidade ambiental da sub-bacia hidrográfica dos Arroios Juá e Caracol : bacia hidrográfica do Rio Caí / RSDamasceno, Maycon Pereira January 2011 (has links)
A Geografia desde a sua concepção como ciência tem no espaço geográfico, o seu principal objeto de estudo, o que nos permite analisar a dinâmica existente entre as relações que se estabelecem entre os diferentes grupos sociais, ao longo do tempo, e a sua materialização no espaço. Através de sua evolução histórica, a ciência geográfica contribuiu de forma significativa para a compreensão das consequências das ações que o homem como agente atuante e modificador do espaço pode acarretar sobre o ambiente natural, buscando analisar e orientar o seu planejamento. Sobre essa perspectiva, esta pesquisa toma como unidade de análise as Bacias Hidrográficas dos Arroios Juá e Caracol. A área de estudo está localizada na região nordeste do estado do Rio Grande do Sul, a Sub-Bacia do Arroio Juá possui uma área de 12487,27 ha, com altitudes que variam entre 200 e 980 metros, abrange os municípios de Caxias do Sul e São Francisco de Paula. O arroio Juá é afluente direito do Rio Caí. O Arroio Caracol, com uma área total de 6631,89 ha, também integra a Bacia hidrográfica do Caí tem sua sub-bacia estendida pelos municípios de Canela e Gramado. Área de estudo desse projeto insere-se na região do Alto Caí sob influência dos remanescentes do Bioma Mata Atlântica no nordeste do estado Rio Grande do Sul. Objetivo principal deste estudo é avaliar e comparar, através da análise de fragilidade ambiental, o nível de intervenção antrópica e a situação ambiental das sub-bacias do Arroio Juá e Caracol, afluentes do Rio Caí, RS. Dessa forma a pesquisa busca fornecer, através de técnicas cartográficas, uma caracterização detalhada das fragilidades de cada sub-bacia. Fez-se uso dos procedimentos operacionais descritos por Ross (1994), quanto ao estudo das fragilidades potencial e emergente. O mapa de fragilidade ambiental gerado é resultado da interpolação dos mapas de uso da terra, declividade e tipo de solo. Por meio desse produto cartográfico pretende-se fornecer subsídios para identificação das áreas com fragilidade potencial e emergente e dessa forma, colaborar com um melhor planejamento do uso dor recursos naturais. / Geography since its conception as science has in geographic space, its main object of study, allowing us to analyze the dynamics between the relationships established between different social groups, over time, and its materialisation in space. Through their historical, geographical science has contributed significantly to the understanding of the consequences of actions the man acting as an agent and modifier of space can have on the natural environment, seeking to analyze and guide your planning. About this perspective, this research takes as its unit of analysis of the Basin Streams Juá and Caracol, a systemic and integrated approach of the various elements, processes and interactions. The study area is located in the northeastern state of Rio Grande do Sul, the Sub-Basin Brook Juá covers the cities of Caxias do Sul and São Francisco de Paula. It has an area of 12487.27 ago, with altitudes ranging between 200 and 980 meters. Juá The stream is a tributary of the River Fall. Arroyo Caracol which also includes the Fall River Basin sub-basin has its extended by the municipalities of Gramado and Canela, with a total area of 6631.89 for. Study area is part of this project in the Upper Fall under the influence of the remnants of Atlantic Forest biome in northeastern Rio Grande do Sul state goal of this study is to evaluate and compare, through analysis of environmental fragility, the level of intervention anthropogenic and environmental situation of the sub-basins and Juá Arroyo Caracol, Fall River tributaries, RS. Thus the research seeks to provide mapping techniques through a detailed characterization of the weaknesses of each sub-basin. Was use of the operating procedures described by Ross (1994), and the study of emerging and potential weaknesses. The map of environmental vulnerability is the result of interpolation generated maps of land use, slope and soil type. Through this cartographic product is intended to provide a basis for identifying areas with potential and emerging weakness and therefore, collaborate with a better plan to use pain natural resources.
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Gestão Ambiental apoiada por SIG na estrada da Colônia, Ilha Grande (RJ): uma visão do futuro. / Environmental Management supported by GIS in road Cologne, Ilha Grande (RJ): a vision of the future.Najara Proença Marques Monteiro 04 May 2012 (has links)
Os SIG Sistemas de Informação Geográfica vêm sendo cada vez mais estudados como ferramentas facilitadoras de análises territoriais com o objetivo de subsidiar a gestão ambiental. A Ilha Grande, que pertence ao município de Angra dos Reis, localiza-se na baía de Ilha Grande no sul do estado do Rio de Janeiro e constitui-se no recorte espacial de análise. Apresenta uma dinâmica ambiental complexa que se sobrepõem principalmente aos usos de proteção ambiental e de atividade turística em uma porção do território em que as normatizações legais são difíceis de serem aplicadas, pois são reflexos de interesses que se manifestam em três esferas do poder a municipal, a estadual e a federal. O objetivo principal desta pesquisa é a realização do processamento digital de imagem para auxiliar a gestão territorial da Ilha Grande. Em foco, a estrada Abraão - Dois Rios, que liga Abraão (local de desembarque dos turistas, principal núcleo da Ilha) a Dois Rios (local de visitação por estudantes e pesquisadores, núcleo que abrigava o presídio, atualmente abriga sede do centro de pesquisa e museu da Universidade do Estado do Rio de Janeiro), ambos protegidos por diferentes categorias de unidades de conservação. A metodologia fundamenta-se no processamento digital de imagem através da segmentação e da classificação supervisionada por pixel e por região. O processamento deu-se a partir da segmentação (divisão de uma imagem digital em múltiplas regiões ou objetos, para simplificar e/ou mudar a representação de uma imagem) e dos processos de classificações de imagem, com a utilização de classificação por pixel e classificação por regiões (com a utilização do algoritmo Bhattacharya). As segmentações e classificações foram processadas no sistema computacional SPRING versão 5.1.7 e têm como objetivo auxiliar na análise de uso da Terra e projetar cenários a partir da identificação dos pontos focais de fragilidade encontrados ao longo da estrada Abraão-Dois Rios, propensos a ocorrências de movimentos de massa e que potencializam o efeito de borda da floresta e os impactos ambientais. A metodologia utilizada baseou-se em análise de campo e comparações de tecnologias de classificação de imagens. Essa estrada eixo de ligação entre os dois núcleos tem significativa importância na história da Ilha, nela circulam veículos, pesados e leves, de serviço, pedestres e turistas. Como resultados da presente foram gerados os mapas de classificação por pixel, os mapas de classificação por região, o mapa fuzzy com a intersecção dos mapas de classificação supervisionada por região e os mapas com os locais coletados em campo onde são verificadas ocorrências de movimentos de massa nas imagens ALOS, 2000, IKONOS, 2003 e ortofotografias, 2006. Esses mapas buscam servir de apoio à tomada de decisões por parte dos órgãos locais responsáveis. / GIS - Geographic Information Systems - have been increasingly studied as tools that facilitate analysis of territorial order to subsidize environmental management. The Big Island, which belongs to the municipality of Angra dos Reis, located in the Bay of Ilha Grande in the southern state of Rio de Janeiro and constitutes the spatial area of analysis. Presents a complex dynamic environment that overlap mainly the uses of environmental protection and tourism activity in a portion of the territory in which legal norms are difficult to apply because they are reflections of interests manifested in three spheres of power - the municipal the state and federal levels. The main objective of this research is the realization of digital image processing to assist territorial management of the Big Island. Focus on the road Abraham - Two Rivers, linking Abraham (landing place for tourists, the main core of the Island) at Two Rivers (site visits by students and researchers, the core that housed the prison currently houses the headquarters of the research center museum and the State University of Rio de Janeiro), both protected by different categories of conservation units. The methodology is based on digital image processing via supervised classification and segmentation by pixel and region. The process occurred from the segmentation (division of a digital image into multiple regions or objects to simplify and / or change the representation of an image) and the image classification process, using pixel classification by classification, and By regions (using the algorithm Bhattacharya). The segmentations and classifications were processed in the computer system SPRING version 5.1.7 and aim to assist in analyzing the usage scenarios and design earth from the identification of the focal points of weakness found along the road Abraham-Two Rivers, prone to occurrences mass movements and to potentiate the effect of forest edge and environmental impacts. The methodology used was based on field analysis and comparisons of technologies for image classification. This road axis connecting the two cores have significant importance in the history of the island, it circulating vehicles, light and heavy, service, pedestrians and tourists. As a result of this the maps were generated by pixel classification, the classification by region maps, map of the intersection with fuzzy supervised classification maps by region and maps with the locations where they are collected in the field verified occurrence of mass movements in ALOS, 2000, IKONOS, 2003 and orthophotos, 2006. These maps seek to serve to support decision-making by local bodies responsible.
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