Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas
Autor(a) principal: | |
---|---|
Data de Publicação: | 2020 |
Tipo de documento: | Tese |
Idioma: | por |
Título da fonte: | Repositório Institucional da UFSCAR |
Texto Completo: | https://repositorio.ufscar.br/handle/ufscar/13106 |
Resumo: | The prestressed hollow core slabs present uncertainties regarding the evaluation of the resistance to the resistant shear force. This is because several parameters influence the shear-resistant mechanism of prestressed hollow core slabs, such as the loss of prestressing, the length of transfer of the prestressing force, the position of the critical breaking section, the height of the hollow core slab and the core shape. This work seeks to evaluate the influence of these variables through tests and computational modelling. The tests were performed on a slab with an non-circular cores and height of 200 mm, from segments cut longitudinally from the slab in order to isolate the rib, and thus avoid the torsion effect during the test. The concrete was characterized in terms of compressive strength, elasticity modulus, fracturing energy, and tensile strength. The latter was compared with the tensile strength obtained from bending tests on hollow core slab segments without prestressing. A series of prestressed segments were brought to ruin by flexion in order to determine the actual loss of prestressing. In addition, slab segments, with and without balance at its end, were brought to ruin by shear force in order to identify the influence of the prestressing force transfer length. A group with non-prestressed segments, only 1.0 meter long, were tested with a notch at a certain height. The purpose of this notch was to force a shear crack. A computational model based on the finite element method was developed, which was calibrated by testing the segments and the 200 mm high hollow slab, as well as a 160 mm high hollow slab tested by another author. From these computational models it was possible to determine the transfer length, the position of the critical section and the portion of the prestressing force in the shear capacity of these slabs. Subsequently, these analyses were also performed on a 320 mm and 400 mm slab. Also, in the numerical models, the prestressing intensity installed was varied to analyse its influence. Thus, it was possible to analyse the concrete and prestressing plots in hollow core slabs with different heights. The results of the experiments showed that it is possible to determine the shear force of the model with and without prestressing for shear tests in the segment. The presence of prestressing modifies the cracking panorama of the segments. Segment testing reduced the effects of torsion. From the flexion tests of the segment with and without prestressing, it was possible to determine the tensile strength in flexing the segments of the slab itself, in addition to the loss of prestressing. The computational models showed the behaviour of concrete and strands deformations, making it possible to identify the transfer length and anchoring length. The prestressing portion, in the resistant shear force, varies from slab to slab, and depends on the properties of the cross section and the eccentricity of the strand. |
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Sales, Marcel Willian ReisFerreira, Marcelo de Araújohttp://lattes.cnpq.br/4199122391532470Araújo, Daniel de Limahttp://lattes.cnpq.br/8801080897723883http://lattes.cnpq.br/9796359192239594a12627df-659d-47af-92f7-aaa4b49e27832020-07-31T22:30:32Z2020-07-31T22:30:32Z2020-07-14SALES, Marcel Willian Reis. Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas. 2020. Tese (Doutorado em Engenharia Civil) – Universidade Federal de São Carlos, São Carlos, 2020. Disponível em: https://repositorio.ufscar.br/handle/ufscar/13106.https://repositorio.ufscar.br/handle/ufscar/13106The prestressed hollow core slabs present uncertainties regarding the evaluation of the resistance to the resistant shear force. This is because several parameters influence the shear-resistant mechanism of prestressed hollow core slabs, such as the loss of prestressing, the length of transfer of the prestressing force, the position of the critical breaking section, the height of the hollow core slab and the core shape. This work seeks to evaluate the influence of these variables through tests and computational modelling. The tests were performed on a slab with an non-circular cores and height of 200 mm, from segments cut longitudinally from the slab in order to isolate the rib, and thus avoid the torsion effect during the test. The concrete was characterized in terms of compressive strength, elasticity modulus, fracturing energy, and tensile strength. The latter was compared with the tensile strength obtained from bending tests on hollow core slab segments without prestressing. A series of prestressed segments were brought to ruin by flexion in order to determine the actual loss of prestressing. In addition, slab segments, with and without balance at its end, were brought to ruin by shear force in order to identify the influence of the prestressing force transfer length. A group with non-prestressed segments, only 1.0 meter long, were tested with a notch at a certain height. The purpose of this notch was to force a shear crack. A computational model based on the finite element method was developed, which was calibrated by testing the segments and the 200 mm high hollow slab, as well as a 160 mm high hollow slab tested by another author. From these computational models it was possible to determine the transfer length, the position of the critical section and the portion of the prestressing force in the shear capacity of these slabs. Subsequently, these analyses were also performed on a 320 mm and 400 mm slab. Also, in the numerical models, the prestressing intensity installed was varied to analyse its influence. Thus, it was possible to analyse the concrete and prestressing plots in hollow core slabs with different heights. The results of the experiments showed that it is possible to determine the shear force of the model with and without prestressing for shear tests in the segment. The presence of prestressing modifies the cracking panorama of the segments. Segment testing reduced the effects of torsion. From the flexion tests of the segment with and without prestressing, it was possible to determine the tensile strength in flexing the segments of the slab itself, in addition to the loss of prestressing. The computational models showed the behaviour of concrete and strands deformations, making it possible to identify the transfer length and anchoring length. The prestressing portion, in the resistant shear force, varies from slab to slab, and depends on the properties of the cross section and the eccentricity of the strand.As lajes alveolares protendidas apresentam incertezas quanto à avaliação da resistência à força cortante resistente. Isso, porque, diversos parâmetros influenciam no mecanismo resistente à força cortante das lajes alveolares protendidas, tais como, a perda de protensão, o comprimento de transferência da força de protensão, a posição da seção crítica de ruptura, a altura da laje alveolar e a forma dos alvéolos. Esse trabalho busca avaliar a influência dessas variáveis por meio da realização de ensaios e modelagem computacional. Os ensaios foram realizados em uma laje com alvéolo oblongo e altura de 200 mm, a partir de segmentos cortados longitudinalmente da laje de modo a isolar a nervura, e, assim, evitar o efeito de torção durante a realização do ensaio. O concreto foi caracterizado quanto a resistência à compressão, módulo de elasticidade, energia de fraturamento e resistência à tração. Esta última foi comparada com a resistência à tração obtida de ensaios à flexão em segmentos de laje alveolar sem protensão. Uma série de segmentos protendidos foram levados à ruína por flexão com a finalidade de determinar a perda real de protensão. Além disso, segmentos de laje, com e sem balanço na sua extremidade, foram levados à ruína por força cortante de modo a identificar a influência do comprimento de transferência da força de protensão. Um grupo com segmentos não protendidos, com apenas 1,0 metro de comprimento, foram ensaiados com entalhe em uma determinada altura. A finalidade deste entalhe era forçar uma fissura por cisalhamento. Um modelo computacional baseado no método dos elementos finitos foi desenvolvido, o qual foi calibrado a partir do ensaio dos segmentos e da laje alveolar de 200 mm de altura, bem como de uma laje alveolar com 160 mm de altura ensaiada por outro autor. Destes modelos computacionais foi possível determinar o comprimento de transferência da força de protensão, a posição da seção crítica e a parcela da força de protensão na resistência à força cortante dessas lajes. Posteriormente, estas análises também foram realizadas em uma laje de 320 mm e outra de 400 mm. Também, nos modelos numéricos foram variadas a intensidade da protensão instalada para analisar sua influência. Assim, foi possível analisar as parcelas de concreto e protensão em lajes alveolares com diversas alturas. Os resultados dos experimentos mostraram que é possível determinar a força cortante do modelo com e sem protensão para os ensaios de cisalhamento no segmento. A presença da protensão modifica o panorama de fissuração dos segmentos. Os ensaios dos segmentos reduziram os efeitos da torção. A partir dos ensaios de flexão do segmento com e sem protensão foi possível determinar a resistência à tração na flexão dos segmentos da própria laje, além da perda de protensão. Os modelos computacionais mostraram o comportamento das deformações do concreto e do aço, sendo assim possível identificar o comprimento de transferência e de regularização das peças. A parcela de protensão, na força cortante resistente, varia de laje para laje, e depende das propriedades da seção transversal e da excentricidade da cordoalha de cada laje.Fundação de Amparo à Pesquisa do Estado de Goiás (FAPEG)FAPEG: 2017.10.267000.513porUniversidade Federal de São CarlosCâmpus São CarlosPrograma de Pós-Graduação em Engenharia Civil - PPGECivUFSCarAttribution-NonCommercial-NoDerivs 3.0 Brazilhttp://creativecommons.org/licenses/by-nc-nd/3.0/br/info:eu-repo/semantics/openAccessLajes alveolares protendidasComprimento de transferênciaForça cortanteTração diagonalFlexo-cortantePrestressed hollow core slabsTransfer lengthShear forceTension shearFlexural shearENGENHARIAS::ENGENHARIA CIVIL::CONSTRUCAO CIVILENGENHARIAS::ENGENHARIA CIVIL::ESTRUTURASEstudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidasNumerical-experimental study of the influence of mechanisms in the resistance to the hollow core slabs capacity strengthinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/doctoralThesis600600a63ace42-f79f-4bf6-b991-277c3dbe6b8dreponame:Repositório Institucional da UFSCARinstname:Universidade Federal de São Carlos (UFSCAR)instacron:UFSCARORIGINALTese Marcel Sales - Versão final.pdfTese Marcel Sales - Versão final.pdfapplication/pdf17100147https://repositorio.ufscar.br/bitstream/ufscar/13106/5/Tese%20Marcel%20Sales%20-%20Vers%c3%a3o%20final.pdfc0af6782e09dc86b0239f4d1877c2403MD55Carta_Aprovação (assinada).pdfCarta_Aprovação (assinada).pdfCarta de aprovação do orientadorapplication/pdf149043https://repositorio.ufscar.br/bitstream/ufscar/13106/3/Carta_Aprova%c3%a7%c3%a3o%20%28assinada%29.pdf21f5c2011b86f4bbded9b9a95785282eMD53CC-LICENSElicense_rdflicense_rdfapplication/rdf+xml; charset=utf-8811https://repositorio.ufscar.br/bitstream/ufscar/13106/6/license_rdfe39d27027a6cc9cb039ad269a5db8e34MD56TEXTTese Marcel Sales - Versão final.pdf.txtTese Marcel Sales - Versão final.pdf.txtExtracted texttext/plain356751https://repositorio.ufscar.br/bitstream/ufscar/13106/7/Tese%20Marcel%20Sales%20-%20Vers%c3%a3o%20final.pdf.txt2b94c2e83b28b54d341120d34feb23d4MD57Carta_Aprovação (assinada).pdf.txtCarta_Aprovação (assinada).pdf.txtExtracted texttext/plain1201https://repositorio.ufscar.br/bitstream/ufscar/13106/9/Carta_Aprova%c3%a7%c3%a3o%20%28assinada%29.pdf.txt9797294937a2a653374a09d1469ce214MD59THUMBNAILTese Marcel Sales - Versão final.pdf.jpgTese Marcel Sales - Versão final.pdf.jpgIM Thumbnailimage/jpeg6165https://repositorio.ufscar.br/bitstream/ufscar/13106/8/Tese%20Marcel%20Sales%20-%20Vers%c3%a3o%20final.pdf.jpgae9a11fa5e28949f483c08bed6a511caMD58Carta_Aprovação (assinada).pdf.jpgCarta_Aprovação (assinada).pdf.jpgIM Thumbnailimage/jpeg13318https://repositorio.ufscar.br/bitstream/ufscar/13106/10/Carta_Aprova%c3%a7%c3%a3o%20%28assinada%29.pdf.jpg8b9b50fe2f615c4dae2ccc47d987f7f8MD510ufscar/131062023-09-18 18:31:59.254oai:repositorio.ufscar.br:ufscar/13106Repositório InstitucionalPUBhttps://repositorio.ufscar.br/oai/requestopendoar:43222023-09-18T18:31:59Repositório Institucional da UFSCAR - Universidade Federal de São Carlos (UFSCAR)false |
dc.title.por.fl_str_mv |
Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas |
dc.title.alternative.eng.fl_str_mv |
Numerical-experimental study of the influence of mechanisms in the resistance to the hollow core slabs capacity strength |
title |
Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas |
spellingShingle |
Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas Sales, Marcel Willian Reis Lajes alveolares protendidas Comprimento de transferência Força cortante Tração diagonal Flexo-cortante Prestressed hollow core slabs Transfer length Shear force Tension shear Flexural shear ENGENHARIAS::ENGENHARIA CIVIL::CONSTRUCAO CIVIL ENGENHARIAS::ENGENHARIA CIVIL::ESTRUTURAS |
title_short |
Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas |
title_full |
Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas |
title_fullStr |
Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas |
title_full_unstemmed |
Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas |
title_sort |
Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas |
author |
Sales, Marcel Willian Reis |
author_facet |
Sales, Marcel Willian Reis |
author_role |
author |
dc.contributor.authorlattes.por.fl_str_mv |
http://lattes.cnpq.br/9796359192239594 |
dc.contributor.author.fl_str_mv |
Sales, Marcel Willian Reis |
dc.contributor.advisor1.fl_str_mv |
Ferreira, Marcelo de Araújo |
dc.contributor.advisor1Lattes.fl_str_mv |
http://lattes.cnpq.br/4199122391532470 |
dc.contributor.advisor-co1.fl_str_mv |
Araújo, Daniel de Lima |
dc.contributor.advisor-co1Lattes.fl_str_mv |
http://lattes.cnpq.br/8801080897723883 |
dc.contributor.authorID.fl_str_mv |
a12627df-659d-47af-92f7-aaa4b49e2783 |
contributor_str_mv |
Ferreira, Marcelo de Araújo Araújo, Daniel de Lima |
dc.subject.por.fl_str_mv |
Lajes alveolares protendidas Comprimento de transferência Força cortante Tração diagonal Flexo-cortante |
topic |
Lajes alveolares protendidas Comprimento de transferência Força cortante Tração diagonal Flexo-cortante Prestressed hollow core slabs Transfer length Shear force Tension shear Flexural shear ENGENHARIAS::ENGENHARIA CIVIL::CONSTRUCAO CIVIL ENGENHARIAS::ENGENHARIA CIVIL::ESTRUTURAS |
dc.subject.eng.fl_str_mv |
Prestressed hollow core slabs Transfer length Shear force Tension shear Flexural shear |
dc.subject.cnpq.fl_str_mv |
ENGENHARIAS::ENGENHARIA CIVIL::CONSTRUCAO CIVIL ENGENHARIAS::ENGENHARIA CIVIL::ESTRUTURAS |
description |
The prestressed hollow core slabs present uncertainties regarding the evaluation of the resistance to the resistant shear force. This is because several parameters influence the shear-resistant mechanism of prestressed hollow core slabs, such as the loss of prestressing, the length of transfer of the prestressing force, the position of the critical breaking section, the height of the hollow core slab and the core shape. This work seeks to evaluate the influence of these variables through tests and computational modelling. The tests were performed on a slab with an non-circular cores and height of 200 mm, from segments cut longitudinally from the slab in order to isolate the rib, and thus avoid the torsion effect during the test. The concrete was characterized in terms of compressive strength, elasticity modulus, fracturing energy, and tensile strength. The latter was compared with the tensile strength obtained from bending tests on hollow core slab segments without prestressing. A series of prestressed segments were brought to ruin by flexion in order to determine the actual loss of prestressing. In addition, slab segments, with and without balance at its end, were brought to ruin by shear force in order to identify the influence of the prestressing force transfer length. A group with non-prestressed segments, only 1.0 meter long, were tested with a notch at a certain height. The purpose of this notch was to force a shear crack. A computational model based on the finite element method was developed, which was calibrated by testing the segments and the 200 mm high hollow slab, as well as a 160 mm high hollow slab tested by another author. From these computational models it was possible to determine the transfer length, the position of the critical section and the portion of the prestressing force in the shear capacity of these slabs. Subsequently, these analyses were also performed on a 320 mm and 400 mm slab. Also, in the numerical models, the prestressing intensity installed was varied to analyse its influence. Thus, it was possible to analyse the concrete and prestressing plots in hollow core slabs with different heights. The results of the experiments showed that it is possible to determine the shear force of the model with and without prestressing for shear tests in the segment. The presence of prestressing modifies the cracking panorama of the segments. Segment testing reduced the effects of torsion. From the flexion tests of the segment with and without prestressing, it was possible to determine the tensile strength in flexing the segments of the slab itself, in addition to the loss of prestressing. The computational models showed the behaviour of concrete and strands deformations, making it possible to identify the transfer length and anchoring length. The prestressing portion, in the resistant shear force, varies from slab to slab, and depends on the properties of the cross section and the eccentricity of the strand. |
publishDate |
2020 |
dc.date.accessioned.fl_str_mv |
2020-07-31T22:30:32Z |
dc.date.available.fl_str_mv |
2020-07-31T22:30:32Z |
dc.date.issued.fl_str_mv |
2020-07-14 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/doctoralThesis |
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publishedVersion |
dc.identifier.citation.fl_str_mv |
SALES, Marcel Willian Reis. Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas. 2020. Tese (Doutorado em Engenharia Civil) – Universidade Federal de São Carlos, São Carlos, 2020. Disponível em: https://repositorio.ufscar.br/handle/ufscar/13106. |
dc.identifier.uri.fl_str_mv |
https://repositorio.ufscar.br/handle/ufscar/13106 |
identifier_str_mv |
SALES, Marcel Willian Reis. Estudo numérico-experimental da influência dos mecanismos na resistência à força cortante de lajes alveolares protendidas. 2020. Tese (Doutorado em Engenharia Civil) – Universidade Federal de São Carlos, São Carlos, 2020. Disponível em: https://repositorio.ufscar.br/handle/ufscar/13106. |
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https://repositorio.ufscar.br/handle/ufscar/13106 |
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Attribution-NonCommercial-NoDerivs 3.0 Brazil http://creativecommons.org/licenses/by-nc-nd/3.0/br/ |
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openAccess |
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Universidade Federal de São Carlos Câmpus São Carlos |
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Programa de Pós-Graduação em Engenharia Civil - PPGECiv |
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UFSCar |
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Universidade Federal de São Carlos Câmpus São Carlos |
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