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Instrumentation for SPS-2Sharkins, Anthony August January 1996 (has links)
No description available.
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Experimental and finite element analysis of Y and YU type contraction joints in concrete pavementsPannila, Indra January 1995 (has links)
No description available.
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Finite element analysis of Y and YU type contraction joints in concrete pavementsBosel, Tod January 1990 (has links)
No description available.
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Experimental analysis of steel dowels used in Y and YU type contraction joints for the repair of concrete pavements subjected to truck loadingRogers, Robert Craig January 1991 (has links)
No description available.
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Evolução temporal da resistencia mecanica em laboratorio, de misturas simulando a reciclagem de pavimento asfaltico com adição de cimento portland / Temporal evolution of mechanical resistance in laboratory, of mixtures simulating asphalt pavement recycling with portland cement additionsGusmão, Claudia Betine 12 December 2008 (has links)
Orientador: João Virgilio Merighi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-12T12:23:13Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008 / Resumo: O presente trabalho visa estudar o processo de reciclagem de pavimento asfaltico com
cimento Portland, atraves da analise de metodo de reciclagem, equipamentos utilizados, procedimentos empregados em campo, alem do estudo das vantagens e desvantagens do uso da reciclagem em pavimentos asfalticos. O trabalho trata ainda de uma forma detalhada o pavimento asfaltico com adicao de cimento Portland, atraves de ensaios tecnologicos simulando em laboratorio, para diferentes dosagens o comportamento mecanico em funcao do tempo do material obtido em campo. / Abstract: This work studies the process of asphalted pavement recycling with cement Portland additive through the analysis of recycling method, equipments and procedures used in the field, in addition to studying the advantages and disadvantages of the use of recycling in asphalted pavement. The work also approaches in detail the recycled asphalt pavement with Portland cement additive, through technological tests through laboratory simulation, to different dosage and the analysis of mechanical behavior through time of that material obtained in field. / Mestrado / Transportes / Mestre em Engenharia Civil
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Pavimentos flexíveis com revestimento asfáltico = avaliação estrutural a partir dos parâmetros de curvatura da bacia de deformação / Flexible pavements : structural evaluation based on deflection basin parametersLopes, Flaviane Melo 20 August 2018 (has links)
Orientador: Rita Moura Fortes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo. / Made available in DSpace on 2018-08-20T02:21:51Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: No Brasil é significativo o crescimento do uso do equipamento tipo Falling Weight Deflectometer - FWD para o levantamento deflectométrico e posterior caracterização estrutural de pavimentos existentes. Esta caracterização ainda é realizada somente através da medida de deflexão máxima. Contudo, o conhecimento isolado da deflexão máxima (D0) pode não ser suficientemente conclusivo para se diagnosticar a condição estrutural do pavimento. Sendo assim, o presente estudo tem como objetivo, por meio de estudo paramétrico, propor uma metodologia simplificada de avaliação da condição estrutural de pavimentos asfálticos com base granular utilizando as medições da bacia deflectométrica. A determinação de parâmetros de curvatura da bacia de deformação, obtidos através de um levantamento deflectométrico, serão utilizados para o desenvolvimento de correlações destes com as deformações críticas geradas na estrutura do pavimento quando solicitado. Através das correlações obtidas, propõem-se modelos simplificados para estimar a vida remanescente de um pavimento em função dos parâmetros deflectométricos. A metodologia proposta mostrou-se promissora. O aproveitamento das informações da bacia deflectométrica pode auxiliar na solução de restauração do pavimento, evitando defeitos precoces por falhas no diagnóstico / Abstract: In Brazil it is significant the increase in the use of an equipment type Falling Weight Deflectometer - FWD for deflection analysis and structural characterization of existing pavements. This characterization is still held only through a maximum deflection measure. However, the isolated association of maximum deflection (D0) may not be conclusive enough to diagnose the structural condition of the pavement. Thus, the current study aims, through parametric study, to propose a simplified structural assessment methodology of asphalt pavement condition with granular base using measurements of deflection basin. The determination of deflection basin parameters, obtained through deflection measurements, will be used for the development of these correlations with significant deformation of pavement structure generated when prompted. Through the correlations obtained simplified models will be proposed to estimate the remaining life of a pavement according to deflection parameters. The proposed methodology has proved to be promising. The use of the information on deflection basin can help out in troubleshooting pavement rehabilitation, avoiding premature failures in diagnosing faults / Mestrado / Transportes / Mestre em Engenharia Civil
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Correlation of Damage Rating Index in Concrete PavementsQutail, Ali 06 May 2021 (has links)
No description available.
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Finite element analysis of Y and YU type contraction joints for concrete pavements using steel dowels as load transfer devicesButt, Aamir S. January 1990 (has links)
No description available.
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Characterization of cracks on ultra thin continuously reinforced concrete pavementsGerber, Johan Andries Kritzinger 03 1900 (has links)
Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The southbound screener lane of the Heidelberg Traffic Control Centre received structural
improvements by means of an ultra thin continuously reinforced concrete pavement
(UTCRCP) overlay. This experimental overlay forms part of the South African National
Roads Agency Limited’s innovative highway repair strategy on existing pavements that have
exceeded design life. The primary objective of this study was to characterize the UTCRCP
overlay with regard to crack spacing formation under accelerated pavement testing (APT).
Characterization comprised of empirical modelling techniques, statistical analysis, non
destructive testing and software simulations. Pavement deflection responses were
empirically and linear elastically converted to input parameters. These parameters were
used in the mean crack spacing prediction model of the Mechanistic-Empirical Pavement
Design Guide (M-E PDG). Observed cracking under APT was recorded and analyzed by
means of descriptive statistics. The outcome of the M-E PDG’s mean crack spacing and the
statistics of the observed cracking were evaluated against cncPave simulations.
Initial shrinkage crack formations ranged from 500 mm to 900 mm, with a mean spacing of
695 mm. Subsequent secondary cracking reduced the segments, delineated by initial
cracking, to intervals consisting of 100 mm to 350 mm. A statistical analysis of the observed
cracking indicated that traffic had little effect on the transverse crack spacing formation. The
observed cracks yielded a mean spacing of 296 mm, compared to the 186 mm of the M-E
PDG mean crack spacing calculation. cncPave simulations indicated that the expected
range of cracking would fall between 237 mm and 350 mm with a probability of 50% that
crack spacing would exceed 265 mm. The 50th percentile of the observed cracks resulted in
a spacing of 233 mm. The APT project was limited to a single test section. No pavement
failures occurred during the APT project. A total of 2.8 million 80 kN load repetitions were
applied to the UTCRCP. However circular crack formations regarded as a punchout
development have formed on the UTCRCP test section.
Circular cracks formed around weaknesses in the pavement system. The prediction of these
punchout formations incorporates the mean crack spacing result. Occurrence of mean crack
spacing forms part of a crack spacing distribution defined by a range. Therefore designing a
punchout prediction model for UTCRCP should include the characteristics and range of the
crack pattern and not merely the mean crack spacing value.
Key Words: UTCRCP, APT, Mean Crack Spacing, Punchout, Descriptive Statistics,
cncPave, M-E PDG, Transverse Cracks, Dense Liquid Foundation, Elastic Solid Foundation. / AFRIKAANSE OPSOMMING: Die suidwaartse moniteerings laan van die Heidelberg Verkeersbeheer Sentrum, het
strukturele verbetering ondergaan deur die konstruksie van ‘n ultradun aaneen-gewapende
betonplaveisel (UDAGBP) wat dien as ‘n deklaag. Hierdie eksperimentele deklaag is deel
van die Suid-Afrikaanse Nasionale Paaie Aggentskap Beperk (SANRAL) se vernuftige
deurpadherstelstrategie vir bestaande deurpaaie waarvan die ontwerplewe verstryk het. Die
primêre doel van hierdie studie is om die UDAGBP te karakteriseer, met betrekking tot
kraakspasiëring, deur middel van Versnelde Plaveisel Toetsing (VPT).
Die karakteriseringsproses het bestaan uit empiriese moduleringstegnieke, statistiese
ontleding, nie-destruktiewe toetsmetodologieë en sagtewaresimulasies. Die plaveiseldefleksiegedrag
is empiries en linieêr elasties ontleed en omgeskakel na invoerparameters.
Hierdie parameters is gebruik in die peilingsmodel vir gemiddelde kraakspasiëring van die
Meganisties-Empiries Plaveisel Ontwerpsgids (M-E POG). Waargenome kraakspasiëring na
die afloop van VPT is opgeteken en deur middel van beskrywende statistiek ontleed. Die
resultate van die M-E POG se gemiddelde kraakspasiëring en die statistiese ontleding van
die waargenome krake is geëvalueer teenoor cncPave simulasies.
Aanvanklike krimpingskrake het gevorm met wisselende kraakspasiëring tussen 500 mm en
900 mm met ‘n gemiddelde spasiëring van 695 mm. Daaropvolgende krake het die
aanvanklike segmente, wat gevorm het tydens die aanvanklike krimpingskrake, verkort na
intervalle van 100 mm tot 350 mm. ‘n Statistiese ontleding van die waargeneemde krake het
aangedui dat verkeer weinig ‘n aandeel het in die dwarskraak-vormingsproses. Die
waargenome krake het ‘n gemiddelde spasiëring van 296 mm in vergelyking met 186 mm
van die M-E POG se gemiddelde kraakspasiëring berekening. cncPave simulasies het
aangedui dat die verwagte kraakspasiëringsgrense tussen 237 mm en 350 mm is en ‘n 50%
waarskynlikheid dat die kraakspasiëring meer as 265 mm is. Die VPT projek is beperk tot ‘n
enkele toetsseksie. Geen plaveiselfalings is waargeneem gedurende die VPT projek nie. In
totaal was 2.8 miljoen as-lasherhalings aangewend op die UDAGBP. Daar het egeter
sirkelvormige kraakformasies, wat beskou word as ponsswigting, ontwikkel op die UDAGBP
toetsseksie.
Sirkelvormige kraakpatrone het gevorm rondom swak plekke in die plaveisel. Die
peilingsmodelle van hierdie ponsswigting maak gebruik van die gimiddelde
kraakspasiëringsresultaat. Die verskynsel van gemiddelde kraakspasiëring in hierdie studie
is deel van ‘n kraakspasiëringsverdeling, gedefinieerd deur ‘n spasiëringsgrens. Daarom
moet die kraakspasiëringskarakteristieke en spasiëringsgrense in ag geneem word in die ontwerpsproses van ‘n UDAGBP ponsswigting-peilings-model, nie slegs die waarde van die
gemiddelde kraakspasiëring nie.
Sleutel woorde: UDAGBP, VPT, Gemiddelde Kraakspasiëring, Ponsswigting, Beskrywende
Statistiek, cncPave, M-E POG, Transversale Krake, Digte Vloeistof Fondasie, Elasties-
Soliede Fondasie.
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Análise experimental e analítica da fissuração de pavimentos de concreto continuamente armados em clima tropical. / Experimental and analytical analysis of continuously reinforced concrete pavements cracking in tropical weather.Cargnin, Andréia Posser 23 November 2016 (has links)
Os primeiros estudos sobre pavimentos de concreto continuamente armados (PCCA) foram desenvolvidos em zonas cujo clima característico é o temperado (EUA, Holanda e Bélgica), não se tendo estudos técnicos acerca do comportamento do pavimento em ambiente tropical. A premissa de funcionamento do PCCA está baseada na não execução de juntas de retração, obrigatórias em pavimentos de concreto simples (PCS), ou seja, as fissuras devido à retração do concreto ocorrem aleatoriamente, sendo controladas pela elevada taxa de armadura longitudinal disposta longitudinalmente ao longo de toda a extensão do pavimento. Como essa armadura não possui função estrutural, pois é colocada acima da linha neutra da placa, no banzo comprimido, sua função é manter as fissuras fortemente apertadas, garantindo suavidade ao rolamento e elevada transferência de carga (LTE), a qual ocorre pelo intertravamento dos agregados nas faces fissuradas, proporcionando assim um pavimento de alta durabilidade e que dispende baixíssimos custos com manutenção. No Brasil, a primeira experiência com PCCA teve início no ano de 2010, quando foram construídas quatro seções de 50 m de extensão cada, consideradas curtas em comparação aos 400 m de extensão de um PCCA rodoviário que podem ser alcançados ao final de um dia de trabalho. O monitoramento contínuo de tais seções mostrou haver uma diferença muito significativa de comportamento, comparado aos PCCA tradicionais, no que tange o tempo decorrido para estabelecimento do padrão de fissuração (a primeira fissura surgiu um ano após a construção), bem como espaçamento médio entre as fissuras, devido à curta extensão das placas e a inexistência de um sistema de ancoragem nas extremidades. Assim, para melhor compreender o comportamento de pavimentos de concreto com armadura contínua com padrões condizentes à realidade rodoviária em ambiente tropical, em janeiro de 2016, foi construído no campus da Universidade de São Paulo o primeiro PCCA de longa extensão do Brasil, com 200 m de comprimento. Foram empregados quatro diferentes tipos de concreto, variando o tipo de cimento e o tipo de agregado, bem como foram empregados aço galvanizado e aço comum. Para entender o comportamento do pavimento sob as condições climáticas brasileiras foram realizados três estudos: levantamento de fissuras (espaçamento e abertura), modelagem analítica do espaçamento entre fissuras através de modelos de previsão de retração em concreto e testes com FWD para avaliação da eficiência de transferência de carga (LTE) entre as fissuras. A análise do padrão de fissuração mostrou que o desenvolvimento das fissuras aconteceu conforme a literatura técnica, tendo início na primeira semana após a concretagem e atingindo aproximadamente 60% do número total de fissuras antes do primeiro mês. As seções centrais possuem o maior número de fissuras, pois estão ancoradas pelas seções de extremidade, onde o surgimento das fissuras é mais lento por conta da falta de ancoragem. As aberturas das fissuras mostraram-se maiores nas posições com aço galvanizado devido à menor aderência aço-concreto nesse caso, em comparação às posições com aço comum. O modelo de previsão de retração no concreto que melhor se aproximou do espaçamento médio desenvolvido em campo foi o modelo do Eurocode 2, com diferenças em torno de 30%, aproximadamente. As análises de LTE mostraram um desempenho muito satisfatório, apesar de a LTE nas regiões com aço galvanizado ter resultado menor do que a LTE nas regiões com aço comum. / The first studies on continuously reinforced concrete pavements (CRCP) were developed in areas in which the typical weather is temperate (United States, Netherlands and Belgium), with no technical studies carried out in tropical weather. CRCP structural premise is based on a slab without construction joints which are required in jointed plain concrete pavements (JPCP); i.e., CRCP cracks due to concrete shrinkage occur randomly being controlled by the high longitudinal reinforcement percentage, positioned longitudinally along the pavement length. As the longitudinal reinforcement has no structural role, because it is placed above the slab neutral axis, in the compression zone, its main function is to keep cracks strongly tight, ensuring a smooth ride and high load efficiency transfer (LTE) at cracks, which occurs through aggregates interlocking, thereby providing a highly durable pavement with low maintenance costs. The first experience with CRCP in Brazil started in 2010, when four experimental sections were constructed. Each section is 50 meters long, short when compared to the traditional CRCP that can extend for over 400 meters providing that concrete pouring does not stop. Continuous monitoring of these sections has shown that the short CRCP behaves differently from traditional CRCP, regarding the time taken for the cracking pattern full development (the first crack was visible on the surface one year after the construction), as well as average cracking space due to the slab\'s short extension and lack of anchorage. Therefore, in order to fully analyze the behavior of a traditional CRCP under tropical weather, in January 2016, the first long extension CRCP in Brazil was built, at the University of São Paulo campus, with 200 meters length. Four types of concrete were applied in the construction, varying cement and aggregate type. Galvanized and ordinary steel were used as well. To analyze the pavement behavior under Brazilian climatic conditions, three studies were carried out: cracks surveys (spacing and width), analytical modeling crack spacing through shrinkage prediction models and Falling Weight Deflectometer testing to evaluate the crack\'s load transfer efficiency (LTE). Cracking pattern analysis has shown cracks development consistent with technical literature. The first cracks appeared during the first week after concrete placement and, before the first month, about 60% of the total cracks number had developed. Central sections presented greatest number of cracks as they are anchored by the outer sections, where cracking occurs slower due to the lack of anchorage. Cracks width was higher in areas with galvanized steel due to the weaker steel-concrete bond, when compared to areas with common steel. The shrinkage prediction model for concrete that better approached the average field crack spacing was the Eurocode 2, with mean difference of 30%. LTE analysis has shown a quite satisfactory performance, even though LTE in areas with galvanized steel is lower than LTE in areas with common steel.
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