Spelling suggestions: "subject:". pavement"" "subject:". lavement""
881 |
ESTUDO LABORATORIAL DE MISTURAS DE FOSFOGESSO, SOLO TROPICAL E CAL PARA FINS DE PAVIMENTAÇÃO / Laboratory study of mixtures of gypsum, lime and tropical soil for pavimentRUFO, Rosely Costa 21 August 2009 (has links)
Made available in DSpace on 2014-07-29T15:01:50Z (GMT). No. of bitstreams: 1
Dissetacao_Rosely_Rufo.pdf: 4926522 bytes, checksum: b40411bb583a2d66970bff3f3b79dc4d (MD5)
Previous issue date: 2009-08-21 / The phosphogypsum, subproduct of the manufacture of the phosphoric acid, became the
objective of studies, due that it requires the availability of large areas to be stored. The
disposal this waste increases the cost of generating company and can even cause a series of
environmental problems. In this context, It has been arisen the interest to study the application
of phosphogypsum in pavement construction, to minimized environmental damage caused by
its storage and to obtained low-cost pavement with satisfactory performance. The objective of
this research was analyzed the behavior of mixtures composed of phosphogypsum (produced
in Catalão-GO region), regional tropical soils and lime, to the implementation of waste in
pavement. Laboratory tests of specific gravity of solids, consistency limits, grain size,
compaction in the intermediate energy, expansion and California Bearing Ratio - CBR,
Methodology Miniatura Compactada Tropical - MCT, were performed for evaluation of the
soil, phosphogypsum, soil-mixtures of phosphogypsum, soil-lime and soil-phosphogypsumlime
behavior. Additional tests of simple compression strength, permeability and chemical
analysis were also performed. The mixture was called Mixture 1 (90% soil + 10%
phosphogypsum), Mixture 2 (80% soil + 20% phosphogypsum), Mixture 3 (70% soil + 30%
phosphogypsum) Mixture 4 (97% soil + 3% limestone lime CHIII), Mixture 5 (94% soil + 6%
limestone lime CHIII), Mixture 6 (91% + 9% limeston lime CHIII), Mixture 7 (81.9%
Catalão-GO soil + 9.1% phosphogypsum + 9% lime CHIII), Mixes 8 (81.9% Catalão-GO soil
+ 9.1% phosphogypsum+ 9% dolomitic lime), Mixes 9 (84.6% Goiânia-GO soil + 9.4%
phosphogypsum + 6% lime CHI). The results are valid for phosphogypsum generated through
the dihydrate process obtained in Catalão-GO city. The results were concluded that between
the soil-phosphogypsum mixtures, the mixture 2 showed the best performance and can be
used in sub-base of pavements. For the lime-soil mixtures, the mixture 6 showed the
possibility to be use on base of pavement with low traffic volume, by presenting CBR greater
than 60%. Soil, lime and phosphogypsum mixtures showed no resistance to be used in layers
of pavement due to the occurrence of chemical reactions between the three materials. These
reactions cause the appearance of mineral etringita. They increase the plasticity and the values
of expansion. In principle, the risk of contamination occurs in the subsoil or groundwater if
the soil-phosphogypsum mixtures are used in works is minimum. However, when waste is
used in pavement construction is necessary to adopt preventive measures and carry out
monitoring. The use of unconventional materials, i.e. phosphogypsum and tropical soil
mixtures, can be considered an interesting alternative from a technical, environmental and
economic point of view / O fosfogesso, subproduto da fabricação do ácido fosfórico, por ser um resíduo que necessita
da disponibilidade de grandes áreas para ser estocado, tornou-se objeto de estudos, uma vez
que sua disposição eleva os custos da empresa geradora e pode, ainda, acarretar numa série de
problemas ambientais. Neste contexto, tem surgido o interesse de estudar a aplicação do
fosfogesso em obras de pavimentação, visando minimizar os danos ambientais causados pela
sua estocagem, além da obtenção de pavimentos de baixo custo com desempenho satisfatório.
O objetivo desta pesquisa foi analisar o comportamento mecânico de misturas compostas de
fosfogesso (produzido na região de Catalão-GO), solos tropicais regionais e cal, visando à
aplicação desse resíduo em pavimentação. Para avaliar o comportamento do solo, fosfogesso,
das misturas solo-fosfogesso, solo-cal e solo-fosfogesso-cal foram realizados ensaios
laboratoriais de peso específico dos grãos, limites de consistência, granulometria,
compactação na energia intermediária, expansão e California Bearing Ratio CBR,
Metodologia Miniatura Compactada Tropical MCT. Também foram realizados a
caracterização química das amostras, difração de raios-X e ensaios complementares de
compressão simples e permeabilidade. As misturas foram denominadas Misturas 1 (90% solo
+ 10% fosfogesso), Misturas 2 (80% solo + 20% fosfogesso), Misturas 3 (70% solo + 30%
fosfogesso), Misturas 4 (97% solo + 3% cal calcítica CHIII), Misturas 5 (94% solo + 6% cal
calcítica CHIII), Misturas 6 (91% solo + 9% cal calcítica CHIII), Mistura 7 (81,9% solo
Catalão-GO + 9,1% fosfogesso + 9% cal CHIII), Mistura 8 (81,9% solo Catalão-GO + 9,1%
fosfogesso + 9% cal dolomítica), Mistura 9 (84,6% solo Goiânia-GO + 9,4% fosfogesso + 6%
Cal CHI). Os resultados encontrados nesta pesquisa são válidos para o fosfogesso gerado
através do processo dihidratado obtido no município de Catalão-GO. Com base nos resultados
obtidos pôde-se concluir que dentre as misturas solo-fosfogesso, a Mistura 2 apresentou
melhor desempenho podendo ser utilizada em sub-base de pavimentos. Para as misturas solocal,
a Mistura 6 apresentou possibilidade de aplicação em bases de pavimento para vias de
baixo volume de tráfego, por apresentar CBR superior a 60%. As misturas de solo, fosfogesso
e cal não apresentaram resistência para serem utilizados em camadas de pavimentos devido à
ocorrência de reações químicas entres os três materiais, provocando o surgimento do mineral
etringita, causando aumento de plasticidade e elevados valores de expansão. Em princípio, o
risco de ocorrer contaminação do subsolo ou do lençol freático caso misturas de solofosfogesso
sejam utilizadas em obras é mínino. No entanto, sempre que for utilizar um
resíduo em obras de pavimentação, torna-se importante adotar medidas preventivas e realizar
monitoramentos. Tem-se, então, que utilização de materiais não convencionais, como
misturas de fosfogesso e solo tropical, pode ser considerada uma alternativa interessante do
ponto de vista técnico e ambiental.
|
882 |
Propuesta de diseño de pavimentos rígidos para subrasantes arenas limosas susceptibles a erosión en el proyecto Vía de Evitamiento del bajo PiuraDiaz Asencios, Edgar, Espinoza Martinez, Gustavo Adolfo 09 November 2020 (has links)
En el presente trabajo de investigación se expone una propuesta de diseño de pavimentos rígidos para subrasantes limo-arenosas susceptibles a erosión con la finalidad de determinar el espesor óptimo de la losa de concreto hidráulico. Este procedimiento fue desarrollado para actuar en zonas donde se presentan fenómenos periódicos y extremos (fenómeno del niño), que ocasionan que el suelo de subrasante pierda su capacidad de soporte hasta alcanzar valores insuficientes (3%≤CBR<6%) a inadecuadas (CBR<3%). La propuesta metodológica usa la guía de diseño AASHTO 1993, resultados de ensayos de métodos de prueba estándar para la relación de soporte de california de laboratorios de suelos compactados y los resultados de ensayos de campo (densidad del suelo por el cono de arena). El procedimiento se desarrolla determinando las propiedades físicas y mecánicas de suelos de subrasantes en su condición operante o natural y evaluando la influencia de los resultados de C.B.R. medidas a densidad natural y al 95%MDS del ensayo de Proctor Modificado como inputs en el diseño. Estos son analizados y comparados en términos de pérdida de capacidad de soporte experimentada en subrasantes en esa condición extrema o crítica y demostrar si en esta condición tiene impacto significativo en el espesor de la losa de concreto hidráulico en términos técnico-económicos. La propuesta es dada como soporte técnico o recomendación técnica para mejorar la práctica de la ciencia del diseño y construcción de caminos viales en el Perú en condiciones similares de fundación y climáticos. / In the present work of investigation, a proposal of design of rigid pavements is exposed with subbasement sandy silts susceptible to erosion to determine the optimum thickness of the slab of hydraulics concrete. This procedure was developed to act in areas where extreme periodic phenomena occur (child phenomenon) that cause the subgrade soil to lose its support capacity until reaching insufficient values (3% ≤CBR <6%) to inadequate (CBR <3 %). The methodological proposal uses the AASHTO 1993 methodology, the test results of standard test methods for the California support relationship of compacted soil laboratories and the results of field tests (soil density by the sand cone). The procedure is developed by determining the physical and mechanical properties of subgrade soils in their operating or natural condition and evaluating the results as inputs in the design. This is analyzed in terms of loss of support capacity experienced in subgrades in that extreme or critical condition and to demonstrate if the impact is significant on the thickness of the hydraulic concrete slab in economic technical terms. The proposal is given as technical support for the practice in road engineering in Peru before the possible problems that could arise due to ignorance in supervisors and designers in similar conditions of foundation and climate. / Tesis
|
883 |
Výzkum v oblasti konstrukčních prvků a dimenzování cementobetonových krytů / Research in the field of construction elements and design of concrete pavementsGrošek, Jiří Unknown Date (has links)
The presented dissertation is focused on research in the field of dowels and design of concrete pavements using the finite element method. The theory part describes the history and the currently used techniques in the world and in the Czech Republic. The practice part of the dissertation contains a description of design methods, diagnostics of concrete pavements by using FWD and a description of laboratory tests on beams with inserted dowels. The results of measurements and modelling are verified on real operating conditions on testing fields. Based on the dissertation results, the amendment of the Czech standard ČSN 73 6123-1 regarding the position of dowels were proposed and approved. In addition, methodological guidelines of the Ministry of Transport regarding the measurements of the dowels and tie bars position and diagnostic by FWD was approved. The conclusion of the work summarizes and emphasizes the results of the dissertation.
|
884 |
Stanovení modulů pružnosti směsí pro podkladní vrstvy vozovek / Determination of elasticity modulus for base layersHepner, Urban January 2018 (has links)
The thesis deals with the experimental determination of the resilient modulus using cyclic triaxial test with the selected unbound mixtures of the base course of the pavement. The aim is to verify whether the proposed modulus-resilient in the regulation TP 170 based on the statisticaly verified data dating several decades ago is still valid in the present. Furthermore, the thesis deals with the dependence between the measured and the calculated values of the modulus resilient Mr from the cyclic triaxial test and the California Bearing Ratio tests. For the classification of the selected materials, further tests are used in the thesis, such as granularity and compaction tests.
|
885 |
Rekonstrukce silnice II/605 Holoubkov – Rokycany (Borek) / Reconstruction of road II/605 Holoubkov - Rokycany (Borek)Němcová, Klára January 2020 (has links)
The topic of the master’s thesis is reconstruction of the the road II/605 between municipality of Holoubkov and municipality of Rokycany (Borek) including local adjustments of the road in urban area of municipality of Svojkovice. The reasons for this reconstruction are insufficient parameters of current condition of the road. In Svojkovice are solved adjustments of crossroads, bus stops, parking bays, pavements and bicycle paths.
|
886 |
Jeseník, Rejvízský most / Rejvíz Bridge in JeseníkDvořák, Jan January 2013 (has links)
The subject of my diploma thesis is to design the intersection of roads I/44 and II/453 in urban area of Jeseník. Part of the proposal is to address traffic and pedestrian connection to the adjacent tertiary roads.
|
887 |
Návrh a posouzení směsi pro asfaltové vrstvy se zvýšenou odolností proti šíření trhlin (SAL) / Desing and evaluation of Bituminous Stress Absorbing Pavement LayerCoufalík, Pavel January 2013 (has links)
This master's thesis deals with the possibility of special asphalt-rubber mixture using - Stress Absorbing Layer (SAL). In the theoretical part the SAL and test methods are described. In the practical part, several different mixtures are designed and selected mixtures were tested. Low-temperature characteristics, permanent deformations, bending tensile relaxation, stiffness modulus and fatigue properties were determined. Based on the test results the mixtures were compared and their benefit is evaluated according to Performance Pavement Design Method, the pavement structure was evaluated by using of computer programme LayEps.
|
888 |
Druhá etapa přeložky I/9 Dubice – Dolní Libchava / The second phase shifting I/9 Dubice - Dolni LibchavaBelda, Miroslav January 2013 (has links)
Master's thesis will deal with the second phase of shifting I/9 Dubice - Dolni Libchava passing west of the Ceska Lipa with an approximate length of 3 km stretch. Estimated start-up of this section is in 2014. This project should build on in the future by-pass Ceska Lipa and Novy Bor, which is currently without funds for implementation by 2025. Traffic load after completion of the by-pass should be approximately 16500 vehicles / 24 hours in 2030. The section is designed in the category S 9.5 with optional solving two major intersections. This thesis will focus on reducing the cost of construction of the section.
|
889 |
Poruchy mostních vozovek a jejich příčiny / Defects of bridge pavement and cause of defectsKubová, Simona January 2014 (has links)
As part of my master's thesis I have conducted a visual inspection and record failures of bridge roadway at selected highway bridges, roads D47, D3 and D8 and photographic documentation, which is included in Annex. Also I have based on their speeches and documents the results of control tests determine their causes and to propose appropriate repair or maintenance.
|
890 |
Návrh okružní křižovatky silnic I/35, I/57 a II/150 při silném levém odbočení / Design of roundabout I/35, I/57 and II/150 with strong left-turnMahdal, Jan January 2014 (has links)
The diploma thesis is focused on insufficient capacity problem of roundabout I/35, I/57 and II/150 in the Valašské Meziříčí town. It is based on engineering survey according to which three possible models are designed. Capacity assesment is made on each of these models. Throug the evaluation is selected the most suitable design of turbo roundabout type "knee", which is technically processed and substantiated by text and drawing documentation.
|
Page generated in 0.0555 seconds