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Comparing the Effect of Reflections, Written Exercises, and Multimedia Instruction to Address Learners’ Misconceptions Using Structural Assessment of KnowledgeSarwar, Gul Shahzad 18 May 2012 (has links)
The study assessed the knowledge structure of Grade 11 physics students and their instructors using Pathfinder networks. Instructors’ structural knowledge was averaged to create a referent pathfinder network. Each student’s pathfinder network was compared with the referent pathfinder network in order to identify misconceptions. These misconceptions served as the basis for remedial instruction. The study was conducted in six sections of Grade 11. Three different types of remedial instruction based on three different chapters from the Grade 11 physics textbook were given to the students at three separate stages. In the first section, students were shown their own and referent pathfinder networks as an intervention during the first stage. The students were asked to reflect on the similarities and differences between them. The researcher gave written concept-oriented exercises based on the differences at the second stage, and multimedia concept-oriented instruction based on the differences was given to the students at the third stage. The order of instruction was counterbalanced in all the six sections. After each stage, students’ pathfinder networks were reassessed and the similarities between students’ and the referent pathfinder networks were calculated to measure the effect of a particular intervention. The study tried to determine which type of remedial instruction given to students best improved the knowledge structure of the students in the domain of physics. Results revealed that the similarity indices around the treatment concepts in the pathfinder networks of the students increased the most from pre- to post-intervention phase because of their reflections, followed by multimedia concept-oriented instruction and written concept-oriented exercises. Most likely, the major reason for this change was the interventions around the treatment concepts by the researcher at three different stages which stimulated and probably changed some of students’ misconceptions. To address the issue of validity, the similarity indices of control concepts in the students’ pathfinder networks were also checked for improvement. The result shows that there is no appreciable improvement in control concepts as there was no intervention around those concepts. Findings support the use of structural assessment of knowledge with pathfinder scaling technique to check the effectiveness of a classroom instruction.
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Structural Assessment of D-Regions Affected by Alkali-Silica Reaction/Delayed Ettringite FormationLiu, Shih-Hsiang 1979- 14 March 2013 (has links)
A combined experimental and analytical program was conducted to investigate the effects of Alkali-Silica Reaction (ASR) and Delayed Ettringite Formation (DEF) on D-regions in reinforced concrete (RC) bridge bents. Four large-scale RC specimens, which represent cantilever and straddle bents in Texas bridges in each specimen, were constructed. The first specimen represented the unexposed control specimen, while the other three were conditioned in the field with supplemental watering to promote ASR/DEF and served as the exposed specimens. The control and two exposed specimens with various levels of ASR/DEF, after eight months and two years of field conditioning, were load tested to failure. The last specimen remains in field with additional exposure to promote ASR/DEF and will be load tested in future studies.
The width and length of preload-induced cracks and developing cracks that initiated in the exposed specimens and grew over time, indicating concrete expansion due to ASR/DEF mechanisms, were measured. Petrographic analysis results of concrete cores extracted from the exposed specimens after their load testing confirmed the formation of ASR gel and minimum accumulation of ettringite. The structural testing results showed that the failure mechanism in all three tested specimens was due to a brittle shear failure in the beam-column joint. However, slightly greater stiffness, strength, and ductility were observed in the exposed specimens as a result of the activation of the reinforcing steel in the specimens due to the expansion of the concrete primarily from ASR, which effectively prestressed and confined the core concrete.
Sectional analysis and Strut-and-Tie Modeling (STM) of the experimental specimens were applied. Three-dimensional nonlinear Finite Element Analyses (FEA) were also conducted to numerically simulate the overall structural performance, internal response, and out-of-plane behavior of the experimental specimens. The effects of varying constitutive relations of the concrete in tension on models of the specimens were compared with the measured experimental response. A method to mimic ASR/DEF effects on exposed specimens was proposed and incorporated into the FEA approach. As a result, forces that prestress and confine the core concrete were effectively applied through the reinforcing steel prior to subsequent structural loading. The three-dimensional FEA approach was able to simulate the out-of-plane behavior of the beam-column joint and the proposed method yielded comparable results with the measured overall and internal behavior of specimens.
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Comparing the Effect of Reflections, Written Exercises, and Multimedia Instruction to Address Learners’ Misconceptions Using Structural Assessment of KnowledgeSarwar, Gul Shahzad 18 May 2012 (has links)
The study assessed the knowledge structure of Grade 11 physics students and their instructors using Pathfinder networks. Instructors’ structural knowledge was averaged to create a referent pathfinder network. Each student’s pathfinder network was compared with the referent pathfinder network in order to identify misconceptions. These misconceptions served as the basis for remedial instruction. The study was conducted in six sections of Grade 11. Three different types of remedial instruction based on three different chapters from the Grade 11 physics textbook were given to the students at three separate stages. In the first section, students were shown their own and referent pathfinder networks as an intervention during the first stage. The students were asked to reflect on the similarities and differences between them. The researcher gave written concept-oriented exercises based on the differences at the second stage, and multimedia concept-oriented instruction based on the differences was given to the students at the third stage. The order of instruction was counterbalanced in all the six sections. After each stage, students’ pathfinder networks were reassessed and the similarities between students’ and the referent pathfinder networks were calculated to measure the effect of a particular intervention. The study tried to determine which type of remedial instruction given to students best improved the knowledge structure of the students in the domain of physics. Results revealed that the similarity indices around the treatment concepts in the pathfinder networks of the students increased the most from pre- to post-intervention phase because of their reflections, followed by multimedia concept-oriented instruction and written concept-oriented exercises. Most likely, the major reason for this change was the interventions around the treatment concepts by the researcher at three different stages which stimulated and probably changed some of students’ misconceptions. To address the issue of validity, the similarity indices of control concepts in the students’ pathfinder networks were also checked for improvement. The result shows that there is no appreciable improvement in control concepts as there was no intervention around those concepts. Findings support the use of structural assessment of knowledge with pathfinder scaling technique to check the effectiveness of a classroom instruction.
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Comparing the Effect of Reflections, Written Exercises, and Multimedia Instruction to Address Learners’ Misconceptions Using Structural Assessment of KnowledgeSarwar, Gul Shahzad January 2012 (has links)
The study assessed the knowledge structure of Grade 11 physics students and their instructors using Pathfinder networks. Instructors’ structural knowledge was averaged to create a referent pathfinder network. Each student’s pathfinder network was compared with the referent pathfinder network in order to identify misconceptions. These misconceptions served as the basis for remedial instruction. The study was conducted in six sections of Grade 11. Three different types of remedial instruction based on three different chapters from the Grade 11 physics textbook were given to the students at three separate stages. In the first section, students were shown their own and referent pathfinder networks as an intervention during the first stage. The students were asked to reflect on the similarities and differences between them. The researcher gave written concept-oriented exercises based on the differences at the second stage, and multimedia concept-oriented instruction based on the differences was given to the students at the third stage. The order of instruction was counterbalanced in all the six sections. After each stage, students’ pathfinder networks were reassessed and the similarities between students’ and the referent pathfinder networks were calculated to measure the effect of a particular intervention. The study tried to determine which type of remedial instruction given to students best improved the knowledge structure of the students in the domain of physics. Results revealed that the similarity indices around the treatment concepts in the pathfinder networks of the students increased the most from pre- to post-intervention phase because of their reflections, followed by multimedia concept-oriented instruction and written concept-oriented exercises. Most likely, the major reason for this change was the interventions around the treatment concepts by the researcher at three different stages which stimulated and probably changed some of students’ misconceptions. To address the issue of validity, the similarity indices of control concepts in the students’ pathfinder networks were also checked for improvement. The result shows that there is no appreciable improvement in control concepts as there was no intervention around those concepts. Findings support the use of structural assessment of knowledge with pathfinder scaling technique to check the effectiveness of a classroom instruction.
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Window opening effects on structural behaviour of historical masonry Fatih MosqueBayraktar, A., Hökelekli, E., Türker, T., Çalik, I., Ashour, Ashraf, Mosallam, A. 16 March 2018 (has links)
Yes / Structural walls of old historical structures are either blind or have openings for functional requirements. It is well known that in and out of plane responses of structural walls are affected by the size, locations, and arrangements of such openings. The purpose of this investigation is to study the window opening effects on static and seismic behaviors of historical masonry old mosques. Fatih Mosque, which was converted from a church, constructed in 914 in Trabzon, Turkey, is selected for this purpose. The mosque is being restored. Structural exterior walls of the mosque were made using stone and mortar materials. When the plaster on the walls was removed during the restoration, 12 window openings were found as blind on the exterior structural walls of the mosque. Within the scope of restoration works, it is aimed to open such blind windows. In order to investigate the effects of the window openings on the structural behavior of the mosque, 3D solid and finite elements models of the mosque with and without window openings are initially developed. The experimental dynamic characteristics such as frequency, damping ratio, and mode shapes of the current situation of the mosque, where some windows openings are blind, are determined using Ambient Vibration Testing. Then, the finite element model of the current situation of the mosque is updated using the experimental dynamic characteristics. The static and seismic time history analyses of the updated finite element model with and without window openings are carried out. Structural behaviors of the mosque with and without window openings are compared considering displacement and stress propagations.
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[en] STRUCTURAL ASSESSMENT OF PIPELINES WITH REAL CORROSION DEFECTS / [pt] AVALIAÇÃO ESTRUTURAL DE DUTOS COM DEFEITOS DE CORROSÃO REAISRICARDO DIAS DE SOUZA 17 November 2003 (has links)
[pt] A avaliação estrutural de dutos com defeitos de corrosão
vem sendo estudada desde o final da década de 60. A
partir dos conceitos da Mecânica da Fratura, foram
elaboradas expressões semi-empíricas que permitiram
estimar a pressão de ruptura de defeitos de corrosão.
Desde então, essas expressões foram sendo ajustadas e
aprimoradas por testes de ensaios destrutivos e análise de
elementos finitos. Os principais métodos desenvolvidos
são o ASME B31G, 085dL, Effective Area, DNV RP F-101
(defeitos isolados) e DNV RP F-101 (defeitos complexos).
Esta tese foi elaborada utilizando alguns dos ensaios
programados para o projeto Produt 600536, e parte dos
seus resultados foi aproveitada neste projeto. Para o
trabalho de tese, foram utilizados cinco espécimes
tubulares de aço API 5L X46, com 3,0 m de comprimento
aproximado, diâmetro nominal de 457,2 mm e espessura
nominal de 6,35 mm. Estes espécimes continham defeitos
reais de corrosão interna, do tipo longo, localizados na
geratriz inferior, e foram retirados do oleoduto Orbel I,
pertencente à Petrobras, durante a sua obra de
reabilitação, em 2001. Os defeitos de corrosão foram
mapeados com medições manuais por ultra-som espaçadas em
20 mm e com medições mecanizadas CSCAN espaçadas em 5mm.
Para cada espécime, foram realizados ensaios de tração em
4 corpos de prova, sendo 2 corpos retirados
transversalmente e 2 longitudinalmente. Estes espécimes
foram instrumentados com extensômetros de resistência
elétrica e pressurizados até a ruptura. Para cada
espécime, foram levantados diversos perfis de corrosão em
função do comprimento estabelecido para o defeito e do
tipo de medição (manual ou mecanizada). A pressão de
ruptura foi estimada pelas equações dos métodos ASME
B31G, 085dL, Effective Area, DNV RP F-101 (defeitos
isolados) e DNV RP F-101 (defeitos complexos),
utilizando planilha Excel e/ou os programas
computacionais RSTRENG e DNV RP F-101. Os valores de
pressão de ruptura estimados para os espécimes,
utilizando os métodos acima relacionados, foram
comparados com as pressões de ruptura reais, obtidas nos
ensaios de pressão. Os resultados confirmaram o
conservadorismo embutido no método ASME B31G e
comprovaram que os métodos Effective Area e DNV RP-F101
(complexo), que utilizam o perfil de corrosão, apresentam
resultados melhores que os métodos ASME B31G e 085dL
e podem ser considerados uma boa ferramenta para avaliar
defeitos de corrosão, considerando somente carregamento
de pressão interna. / [en] Structural assessment of pipelines with corrosion defects
has been studied since the late 1960s. From the principles
of fracture mechanics, semi-emprical mathematical
expressions have been developed for predicting burst
pressure of corroded pipes. Subsequently, these expressions
have been modified and calibrated based on the results from
finite element analyses and laboratory burst tests. The
main methods are ASME B31G, Modified B31G (version 0.85 dL),
Effective Area and DNV RP-F101 for single and complex
shaped defects. This thesis was done utilizing some
laboratory tests from Produt 600536 Project. For
this study, five specimens with 3.0 meters each were
removed from Petrobras pipeline (Orbel I), during its
rehabilitation. The pipe material was API 5L X46,
18 diameter and 0.25 wall thickness. These specimens had
real internal corrosion with very long defect length, at
the 6:00 o`clock position. The corrosion defects were
mapped by manual ultrasound, at 20 mm intervals, and
mecanized ultrasonic measurements CSCAN at 5 mm intervals.
For each pipe, the yield strength and ultimate strength
were determined by tension tests of 4 specimens, 2
removed from transverse and 2 longitudinal. Every pipe
specimen was monitored by strain gages and pressurized up
to the point of rupture. For each specimen different
profiles were determined depending on the length defined
for the defect and for the intervals of measurements. The
burst pressure was predicted by the following methods: ASME
B31G, Modified B31G (version 0.85 dL), Effective Area and
DNV RP-F101 for single and complex defects. These predicted
rupture pressures were compared with the real burst
pressures. The results confirmed the conservatism of the
ASME B31G method and demonstrated that the Effective
Area and DNV RP-F101 for complex shaped defects methods can
be considered good for evaluating longitudinal corrosion
defects, considering only internal pressure load.
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[en] STRUCTURAL ASSESSMENT OF PIPELINES WITH BLUNT CORROSION DEFECTS COINCIDENT WITH LONG-SEAM WELDS / [pt] AVALIAÇÃO ESTRUTURAL DE DUTOS COM DEFEITOS DE CORROSÃO COINCIDENTES COM A SOLDA LONGITUDINALSERGIO IBAJE OLIVEIRA BUENO 19 October 2007 (has links)
[pt] A redução de espessura de parede causada por corrosão é
um
dos defeitos que mais afetam a integridade dos dutos.
Estes defeitos podem ocorrer no metal base, nas soldas
longitudinais ou circunferenciais, bem como nas zonas
afetadas pelo calor. Os métodos de avaliação da
resistência remanescente introduzem ressalvas ou proíbem
o
tratamento de defeitos de corrosão coincidentes com as
juntas soldadas. No presente trabalho foram avaliados os
níveis de segurança dos métodos usuais de avaliação da
resistência de dutos com defeitos introduzidos na região
da solda longitudinal de tubos soldados por arco
submerso.
Os tubos testados eram de aço C-Mn fabricados na década
de
60 e foram retirados de operação após uma campanha
superior a 30 anos. Com estes tubos foram fabricados 5
espécimes, cada qual com 1 defeito externo produzido por
eletro-erosão, sendo posteriormente submetidos a testes
de
pressão monitorados. Foram realizados ensaios de tração,
ensaios de impacto Charpy e ensaios de dobramento, para
determinação das propriedades mecânicas do metal de
base,
do metal de solda e da zona termicamente afetada (ZTA).
Foram realizados também ensaios metalográficos do metal
de
base e do metal de solda, análise química do metal de
base
e do metal de solda e medição das tensões residuais no
metal de solda. A aplicação dos métodos de nível 1 (ASME
B31G, 085dL, RPA, DNV isolado e PCORRC) resultou em
pressões previstas inferiores às pressões reais de
ruptura
para defeitos de formato esférico. Para defeitos de
seção
retangular a aplicação dos métodos de nível 1 resultou
em
pressões superiores às pressões reais. A aplicação dos
métodos de nível 2 (Effective Area e DNV geometria
complexa) resultou em pressões previstas superiores às
pressões reais de ruptura para defeitos de formato
esférico e de seção retangular. As análises das fraturas
indicaram que não ocorreu falha por deficiência de
tenacidade em nenhum espécime. A corrosão alveolar leve
pré-existente na superfície interna dos espécimes foi
apontada como causa mais provável das pressões previstas
superiores às pressões reais de ruptura. / [en] One of the most important issues that affects pipeline
integrity is corrosion-caused metal loss. This type of
defect can occur over the pipe body, seam or girth welds
or even on heat affected zones. Pipeline remaining
strength criterions are restricted or even prohibited for
assessing corrosion defects coincident with weld regions.
This present work investigated the reliability of the most
common assessment criteria for corroded pipes when defects
were coincident with seam weld region in submerged arc
welded pipes. The tested specimens were C-Mn steel pipe,
from a pipeline manufactured in the 60´s and had operated
for over 30 years. Five external defects were created on
five pipe specimens and pressure tested until rupture.
Stress, charpy V-notch and bending tests were carried out
to find the mechanical properties of the welded joints.
Microstructure and chemical composition from base metal
and weld metal were also analyzed. Residual stresses on
welds were measured. The level 1 criterion (ASME B31G,
085dL, RPA, DNV single and PCORRC) applications have
underestimated failure pressure for spherical shaped
defects. On the other hand, the same criterions have
overestimated failure pressure for rectangular shaped
defects. The level 2 criterions (Effective Area e DNV
complex geometry) application overestimated failure
pressure for all 5 specimens with both spherical and
rectangular shaped defects. Fracture analyses have
indicated that no specimen had a toughness controlled
failure. Internal pit corrosion that was found after
pressure testing is recognized as the most probable cause
of underestimated pressure forecasts.
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Evaluación estructural del Museo de Sitio Bodega y Quadra ante un evento sísmico severoAnampa Vilcas, Oscar Alonso, Loyola Carranza, Lucia Isabel January 2015 (has links)
El Museo de Sitio Bodega y Quadra es el primer museo de sitio del Centro Histórico que muestra detalles del estilo de vida en la Lima antigua. Declarada Patrimonio Cultural Inmueble Colonial por el INC, actual Ministerio de Cultura; es por ello que consideramos importante realizar la evaluación estructural del mismo ante un evento sísmico severo. Dicha evaluación se ha realizado mediante el programa “VisualFEA”, el cual se basa en la teoría de los elementos finitos, además se ha respetado la norma de diseño peruana y las consideraciones necesarias por ser, la estructura en estudio, un monumento histórico. La presente es una investigación aplicada, cuantitativa, explicativa y descriptiva; de diseño no experimental, transversal y prospectivo. Se concluye que la estructura no cumple los desplazamientos mínimos, según norma, al someterla al sismo severo; por lo que se procede a plantear la propuesta de reforzamiento estructural haciendo uso de las técnicas de reconstrucción local y refuerzo externo, evitando afectar la integridad y la autenticidad de los materiales por tratarse de un patrimonio cultural.
The museum of site Bodega y Quadra is the first museum of the historic center which shows the old´s life style of lima citizen. It was named Cultural Heritage Colonial Property by the Ministerio de la Cultura; because of that reason we considered important to realize the structural assessment of this museum to prevent any problem in case of a severe earthquake. This thesis has been done using the “VisualFEA” software which is based on the theory of the finite elements, besides it has been considered the Peruvian regulation of design and the properly considerations since it is a Heritage Property. This is an applied, quantitative, descriptive and explanatory research; design not experimental, transversal and prospective. Concludes that the structure does not meet minimum displacement, as a rule, when subjected to sever earthquake; so it proceeds to raise the proposed structural reinforcement using the local reconstruction technique and external reinforcement, preventing affect the integrity and authenticity of the materials because it is a historical monument.
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[pt] ANÁLISE DA SAÚDE DE ESTRUTURAS DE CONCRETO COM O GPR / [en] HEALTH ASSESSMENT OF CONCRETE STRUCTURES WITH GPRPAOLA MACHADO BARRETO MANHAES 20 June 2022 (has links)
[pt] Essa tese apresenta as questões experimentais relativas à avaliação da saúde
de estruturas de concreto com o objetivo de propor uma alternativa à avaliação
subjetiva tradicional de estruturas civis, complementando-a com uma avaliação
mais objetiva utilizando o GPR. A ênfase foi na validação de um procedimento
sólido de avaliação da saúde de edifícios, de estações de tratamento de águas
residuais e de túneis. O GPR foi escolhido por ser considerado um dos métodos de
ensaios não destrutivos mais adotados para investigação de estruturas de concreto
devido à sua relativa insensibilidade às condições ambientais, ter alta resolução,
eficácia e disponibilidade de resultados preliminares em tempo real. A pesquisa
desenvolvida nessa tese teve ênfase na verificação de as-built da construção,
detecção de danos, locação e quantificação de armadura que são de grande interesse
no contexto do controle estrutural. Os resultados apresentados nessa tese
demonstram que o Ground Penetrating Radar (GPR) pode ser uma ferramenta
muito útil para produzir projetos de detalhamento estrutural já que ele pode estimar
espessura de recobrimento de concreto e profundidade e locação do reforço. Os
resultados também mostram que a deterioração do concreto, bem como a corrosão
das barras podem ser verificados após a análise de atributos fornecidos pela
verificação feita com o GPR. Danos são detectados por meio da redução da
profundidade do refletor, aumentando a amplitude das ondas eletromagnéticas e
aumentando a atenuação expressa pelo gráfico de dB decay. Além disso, também
verificou-se que a condição da barra de aço pode ser avaliada através de fatias em
diferentes tempos/profundidade, obtidas na prospecção tridimensional.
Adicionalmente, o programa experimentado também avaliou a viabilidade de
empregar o GPR na avaliação da distribuição de fibras de aço em revestimento de
túnel de concreto projetado, considerando-se o GPR como uma ferramenta útil para
monitoramento e mapeamento in situ durante a o método de construção NATM de
túneis. Os resultados dos ensaios realizados em prismas de concreto auto adensável
reforçado com fibra de aço demonstraram que a distribuição das fibras não é
uniforme. O processamento digital de imagem mostrou que as fibras não são
distribuídas uniformemente e há variação do número de fibras em diferentes seções
do prisma. A análise estatística realizada nos resultados também identificou que a
distância entre as fibras também varia. Quando compara-se os resultados obtidos
com o GPR e os resultados obtidos das análises digitais de imagens percebe-se uma
boa relação entre ambos. Também foi observado que a amplitude do sinal do GPR
não apenas fornece informações sobre a distribuição das fibras, mas também sobre
regiões com ausência delas. Com base nos resultados do programa experimental,
acredita-se que o GPR possa fornecer um feedback imediato das informações e pode
ser usado como uma ferramenta de ajuste dinâmico no projeto NATM. / [en] This thesis presented the experimental issues concerning the health
assessment of concrete structures with the desire to replace the traditional subjective
assessment of civil structures with a more objective assessment using the GPR. The
emphasis here was on validating a sound procedure of health assessment for
buildings, wastewater treatment stations and concrete test specimens. GPR was
chosen since it is considered one of the most popular non-destructive testing
methods adopted for concrete structure imaging because of its relative insensitivity
to ambient conditions, high resolution, effectiveness, and availability of real-time
images The research carried out in this thesis emphasized on as-built designing,
damage detection, location, and quantification, which is of interest in the context of
structural control. The results presented in this thesis demonstrated that the groundpenetrating radar (GPR) could be used as a useful tool in producing structural
detailing drawings since it can provide the thickness of covering concrete and the
depth and location of reinforcement. The results also show that deterioration of
concrete mass and corrosion of its rebars could be also be assessed by the attributes
provided by a GPR scan. Damages are detected by reducing the depth of the
reflector, increasing the amplitude of EM waves and increasing attenuation
expressed by the dB decay. Further to these, it was also indicated that the rebar
condition can be assessed through slices at different times/depths obtained from a
3-D survey. In addition to that, the program also assessed the feasibility of GPR in
evaluating steel fiber distribution within short beam test specimens used in several
standard test methods for determining mechanical properties. Results revealed that
the distribution of steel fibers within a beam is not uniform. Digital and processed
images showed that fibers are not evenly distributed and there is a disparity between
the numbers of fibers in different sections of the short beam. A statistical analysis
performed on the results also found that the distance between fibers also varies
within the short beam. When sketches of the emitted and recorded GPR signal in a
single radar trace mode are compared to the digital and processed images it was
perceived a good relationship between the GPR signal and the distribution of steel
fibers within the short beam. It was additionally noticed that GPR signal amplitude
not only supplies information on how the fibers are close to each other but also
reflects regions with the absence of fibers. Results have also shown that a GPR
system using a high-frequency antenna could assess weaker zones of steel fiber
reinforcement within self-consolidating concrete short beams.
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Méthode de diagnostic à grande échelle de la vulnérabilité sismique des Monuments Historiques : Chapelles et églises baroques des hautes vallées de Savoie / Large-scale seismic vulnerability assesment method for the masonry architectural heritage : baroque chapels and churches of the French SavoyeLimoge, Claire 01 April 2016 (has links)
L’objectif de ce travail est de proposer une méthode d’analyse de vulnérabilité sismique adaptée à l’étude d’un patrimoine historique complet très étendu, indépendamment de la renommée de chaque bâtiment. En effet la grande vulnérabilité sismique du patrimoine ancien, très souvent en maçonnerie, impose, afin d’éviter tout dommage irréparable, de se donner les moyens d’intervenir en amont. Notre démarche doit donc répondre à trois impératifs principaux: développer des outils de choix à grande échelle afin de hiérarchiser les besoins, offrir une analyse pertinente du comportement sous séisme d'une structure historique maçonnée même en première approche, et trouver des méthodes pour gérer le nombre important d’incertitudes qui caractérise le diagnostic des édifices anciens. Pour ce faire, nous étudions les églises et chapelles baroques des hautes vallées de la Savoie française, témoignages d'une période particulièrement prospère dans l'histoire de la Savoie et d'un mouvement artistique unique dans un environnement hostile. Dans ce contexte nous avons donc développé ou adapté différents outils afin de pouvoir traiter les particularités des édifices anciens et utiliser pour des édifices anciens en maçonnerie rustique les potentialités des techniques proposées pour les édifices modernes : modélisations numériques non-linéaires dynamiques temporelles, mesures vibratoires in-situ, analyse multi modale non-linéaire. / The aim of this thesis is to propose a seismic vulnerability assessment method well suited to the study of a complete historical heritage, regardless of the prestige of each building. Indeed the great seismic vulnerability of the historical heritage, often in masonry, requires to act preventively in order to avoid irreparable damage. Our approach must tackle three main requirements: to develop large-scale tools of choice to prioritize the needs, to provide relevant analysis of seismic behavior on the structural scale even in the first study, and to manage the large number of uncertainties characterizing the old buildings structural assessment. To this aim, we study the baroque churches and chapels in the high valleys of the French Savoie. They witness to a particularly prosperous period in the history of Savoy and a unique artistic movement adapted to a harsh environment. In this context we have therefore developed or adapted different tools in order to handle the peculiarities of the old buildings. This way we can use the today proposed techniques for modern buildings to study these ancient buildings in rustic masonry: non-linear temporal dynamics numerical modeling, vibratory in situ measurements, non-linear multi modal analysis.
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