Submitted by Erika Demachki (erikademachki@gmail.com) on 2015-05-22T16:58:51Z No. of bitstreams: 2 Dissertação - Jorge Hernan Garcia Homez - 2014.pdf: 6822156 bytes, checksum: ee54639ad53f9e91bb703af1cb86d568 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Erika Demachki (erikademachki@gmail.com) on 2015-05-22T18:14:52Z (GMT) No. of bitstreams: 2 Dissertação - Jorge Hernan Garcia Homez - 2014.pdf: 6822156 bytes, checksum: ee54639ad53f9e91bb703af1cb86d568 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-05-22T18:14:52Z (GMT). No. of bitstreams: 2 Dissertação - Jorge Hernan Garcia Homez - 2014.pdf: 6822156 bytes, checksum: ee54639ad53f9e91bb703af1cb86d568 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-08-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Studies developed by the state road agency (AGETOP) in 2010, regarding the road infrastructure in the state of Goiás, indicated a need for rebuild 60% of the road network to reestablish its service level. To this end, in 2011, was create the program of road restoration "Rodovida", which aims to restore road infrastructure in the state along four years. In order to obtain parameters for evaluation of performed services, was signed an agreement between the government inspection agency (GO-CGE) and the federal university (UFG). This investigation was developed with the goal to made structural and functional analysis of restored pavements using full depth reclamation technique with gravel addition, to evaluate if the solutions defined in the projects enable the restored pavements meet, or not, the technical parameters of the current road standards, and therefore provide parameters for the incorporation of these reconstruction techniques in future projects. For this study were select three roads with pavements reconstruction in progress, in which procedures for recycling and compacting base monitored by sand bottle test, Speedy Moisture Test and the Dynamic Cone Penetrometer (DCP). Also deformed samples of recycled material for laboratory testing were collect, aiming to propose a model that relates California Bearing Ratio (CBR) with the Penetration Index (DN) for bases added crushed gravel, obtained from the analysis with the DCP in compacted specimens. For structural analysis, were performed field DCP tests to determine the resistance to dynamic penetration and stratigraphic evaluation. As well as testing with Benkelman beam for determining deflections. With the stratigraphy data collected from DCP and displacement basins with the Benkelman beam were determined resilience modulus through back analysis with the aid of the KENLAYER iterative tool. The results obtained with DCP showed thickness variation in the recycled layers, showing the need for greater control during restoration process. Respect to the penetration index determined for the tested bases, these values had increased variability that may be associated with loss control in the executive process, now for sub-base and subgrade layers were determined heterogeneous values, concluding that although high strength present in the recycled bases, this resistance, as well as the thickness of the bases, is heterogeneous. In terms of deflection, the three studied roads showed values within a satisfactory variation range, although some parts were identify with large values of deflection. In terms of back calculated modules, the obtained results can be considered heterogeneous, which may be associated to the recycling technique used or the fact that were adopt different restoration solutions along the evaluated section on a highway. As such, is concluded that even being adopted similar recycling solutions in the three studied roads, the analysis shows distinct behaviors connected mainly to executive processes used. / Estudos desenvolvidos pela Agência Goiana de Transportes e Obras (AGETOP) a respeito da infraestrutura rodoviária do estado de Goiás, no ano 2010, indicaram a necessidade de reconstrução de 60% para recompor seu nível de serviço. Para tanto, em 2011, foi criado o programa de restauração rodoviário “Rodovida”, o qual visa recuperar a infraestrutura viária do estado ao longo de quatro anos. Com a finalidade de obter parâmetros para avaliação dos serviços executados, foi firmado um convênio entre a Controladoria Geral do Estado de Goiás (CGE-GO) e a Universidade Federal de Goiás (UFG). Esta dissertação foi desenvolvida com o objetivo de realizar análises estruturais e funcionais de rodovias restauradas com emprego da técnica de reciclagem profunda a frio “in situ” e incorporação de brita, visando avaliar se as soluções definidas nos projetos possibilitam que os pavimentos restaurados atendam, ou não, parâmetros técnicos das normas rodoviárias atuais, e assim fornecer parâmetros para a incorporação dessas técnicas de reconstrução em futuros projetos. Para tanto foram selecionadas três obras de reconstrução de pavimentos em andamento, nas quais foram monitorados os procedimentos de reciclagem e compactação de base através de ensaios de frasco de areia, “Speedy Moisture Test” e o Penetrômetro Dinâmico de Cone (DCP). Também foram coletadas amostras deformadas do material reciclado para ensaios de laboratório, visando propor um modelo que relacione o Índice de Suporte California (ISC) com o Índice de Penetração (DN) para bases de cascalho com acréscimo de brita, obtido a partir do ensaio com o DCP em corpos de prova compactados. Para a análise estrutural, foram realizados ensaios de DCP em campo para determinação da resistência à penetração dinâmica e avaliação estratigráfica, assim como ensaios com a viga Benkelman, para a determinação das bacias de deflexões. Com os dados de estratigrafia coletados com o DCP e as bacias de deslocamento com a viga Benkelman, foram determinados os módulos de resiliência por meio de retroanálise interativa com auxílio do programa KENLAYER. Os resultados obtidos com o DCP mostraram a variação nas espessuras das camadas recicladas, gerando a necessidade de realizar um maior controle durante a execução. Com relação ao índice de penetração determinado para as bases ensaiadas, esses valores apresentaram maior variabilidade que pode estar associada à falta de controle no processo executivo; já nas camadas de sub-base e subleito foram determinados valores heterogêneos, concluindo que embora as bases recicladas apresentem elevada resistência, essa resistência, assim como a espessura das bases, é heterogênea. Em termos de deflexão, as três rodovias apresentaram valores dentro de uma faixa de variação considerada satisfatória, apesar de serem identificadas algumas regiões com elevados valores de deflexão. Em termos de módulos retroanalisados, os resultados obtidos podem ser considerados heterogêneos, o qual pode ser associado ou com a técnica de reciclagem utilizada ou ao fato de terem sido adotadas diferentes soluções de restauração ao longo do trecho avaliado numa rodovia. Sendo assim, conclui-se que mesmo sendo adotadas soluções de reciclagem semelhantes nas três rodovias estudadas, as análises realizadas mostram comportamentos distintos vinculados, principalmente, a processos executivos utilizados.

This thesis investigates the application of In-Situ Recycling and provides guidelines for localities to aid in the selection of recycling methods, as well as documents a local government's experience with Cold In-Place Recycling. The recycling methods discussed in this study include Cold In-Place Recycling (CIR), Hot In-Place Recycling (HIR), and Full Depth Reclamation (FDR). These methods are performed onsite and in-place in a continuous process of milling, mixing, and placement. The In-Situ Recycling guidelines include suggestions based on: traffic characteristics, existing road condition, distress types, road access, local climate, road geometry, and other road characteristics. The guidelines are based on information from sources including NCHRP Synthesis 421, American Recycling and Reclamation Association (ARRA), FHWA, and state agencies with recycling experience. This study also resulted in documenting obstacles that localities may face when in-situ recycling, as well as the impact of limited experience with recycling. The study also evaluated the construction of Cold In-Place Recycled pavement sections in Christiansburg, VA, using Falling Weight Deflectometer (FWD) and Ground Penetrating Radar (GPR). Additionally, using the FWD and GPR data, alternate recycled designs were proposed in addition to a cost comparison to a conventional design. / Master of Science

Full-depth reclamation (FDR) in conjunction with cement stabilization is an established practice for rehabilitating deteriorating asphalt roads. Conventionally, FDR uses dry cement powder applied with a pneumatic spreader, creating undesirable fugitive cement dust. The cement dust poses a nuisance and, when inhaled, a health threat. Consequently, FDR in conjunction with conventional cement stabilization cannot generally be used in urban areas. To solve the problem of fugitive cement dust, the use of cement slurry, prepared by combining cement powder and water, has been proposed to allow cement stabilization to be utilized in urban areas. However, using cement slurry introduces several factors not associated with using dry cement that may affect road base strength, dry density (DD), and moisture content (MC). The objectives of this research were to 1) identify construction-related factors that influence the strength of road base treated with cement slurry in conjunction with FDR and quantify the effects of these factors and 2) compare the strength of road base treated with cement slurry with that of road base treated with dry cement. To achieve the research objectives, road base taken from an FDR project was subjected to extensive full-factorial laboratory testing. The 7-day unconfined compressive strength (UCS), DD, and MC were measured as dependent variables, while independent variables included cement content; slurry water batching temperature; cement slurry aging temperature; cement slurry aging time; presence of a set-retarding, water-reducing admixture; and aggregate-slurry mixing time. This research suggests that, when road base is stabilized with cement slurry in conjunction with FDR, the slurry water batching temperature; haul time; environmental temperature; and presence of a set-retarding, water-reducing admixture will not significantly affect the strength of CTB, provided that those factors fall within the limits explored in this research and are applied to a road base with similar properties. Cement content and cement-aggregate mixing time are positively correlated with the strength of CTB regardless of cement form. Additionally, using cement slurry will result in slightly lower strength values than using dry cement.