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Improving corrosion resistance of post-tensioned substructures emphasizing high performance grouts /Schokker, A. J. January 1999 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1999. / Vita. Includes bibliographical references (leaves 306-312). Available also in a digital version from Dissertation Abstracts.
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Influência da aderência graute/bloco cerâmico estrutural no comportamento mecânico do conjuntoGuarnieri, Leonel de Oliveira January 2017 (has links)
Atualmente, a alvenaria estrutural é utilizada em empreendimentos habitacionais de larga escala, nos quais as exigências de racionalização, controle, rapidez e custo são mais bem contemplados pelo sistema. No Brasil, existem empreendimentos de até 16 pavimentos construídos com blocos de alta resistência e alto controle tecnológico. A construção de edificações com maiores alturas exige o aumento da capacidade de absorção de esforços de compressão e tração. Para isso, são inseridas barras de aço nos vazados dos blocos e consolidadas com graute, a fim de aumentar a capacidade portante do conjunto. Entretanto, a influência da aderência graute/ bloco cerâmico no comportamento mecânico da alvenaria estrutural ainda é uma dúvida, visto que a NBR 15812 - 1 (ABNT, 2010) não especifica um valor de resistência para aderência graute/ bloco cerâmico, somente para graute/ aço. Frente a essa constatação, a presente pesquisa tem o objetivo de avaliar a influência da aderência graute/ bloco cerâmico estrutural no comportamento mecânico do conjunto, para determinar um valor de tensão de aderência que possa contribuir com a NBR 15812-1 (ABNT, 2010) Para isso, foram utilizados quatro tipos de blocos cerâmicos, com variação da geometria interna dos vazados e resistência mecânica à compressão. O graute foi padronizado em somente uma resistência, sendo essa de 30 MPa. Para desenvolvimento da pesquisa, inicialmente foi realizada a caracterização dos materiais e, posteriormente, realizados ensaios de push-out, resistência à compressão de blocos preenchidos com graute e microscopia óptica. Os resultados revelaram que a aderência graute/ bloco cerâmico estrutural é superior à resistência mecânica à tração do bloco cerâmico, e que a ruptura do conjunto ocorre primeiramente no bloco. Os resultados também constataram aumento da resistência mecânica à compressão axial nos blocos preenchidos com graute. / Currently, structural masonry is used in large-scale housing projects, in which the requirements of rationalization, control, speed and cost are better covered by the system. In Brazil there are projects of up to 16 floors built with high resistance and high technological control blocks. The construction of buildings with higher heights requires the increase of the capacity of absorption of compression and traction forces. For this, steel bars are inserted into hollow blocks which are then consolidated with grout in order to increase the load-bearing capacity of the assembly. However, the influence of ceramic block/grout adhesion in the mechanical behavior of structural masonry is still unknown since the NBR 15812-1 (ABNT, 2010) standard does not specify a resistance value for grout/ceramic block adhesion, only for grout/steel adhesion. In view of this finding, the present research has the objective of evaluating the influence of the structural ceramic block/grout adhesion on the mechanical behavior of the assembly in order to determine a value of adhesion tension that can contribute to the NBR 15812-1 (ABNT, 2010) standard For this purpose four types of ceramic blocks with a variation in the internal geometry of the hollow spaces and mechanical strength to compression were used. Grout was standardized in only one strength of 30 MPa. For development of the research, initially the characterization of the materials was performed and, subsequently, the tests of push-out and compressive strength of grout-filled blocks and light microscopy. The results showed that the grout/ceramic block adhesion is superior to the mechanical tensile strength of the ceramic block and, therefore, the rupture of the assembly will occur first in the block. The results also showed a significant increase of the mechanical resistance to axial compression in blocks filled with grout.
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Influência da aderência graute/bloco cerâmico estrutural no comportamento mecânico do conjuntoGuarnieri, Leonel de Oliveira January 2017 (has links)
Atualmente, a alvenaria estrutural é utilizada em empreendimentos habitacionais de larga escala, nos quais as exigências de racionalização, controle, rapidez e custo são mais bem contemplados pelo sistema. No Brasil, existem empreendimentos de até 16 pavimentos construídos com blocos de alta resistência e alto controle tecnológico. A construção de edificações com maiores alturas exige o aumento da capacidade de absorção de esforços de compressão e tração. Para isso, são inseridas barras de aço nos vazados dos blocos e consolidadas com graute, a fim de aumentar a capacidade portante do conjunto. Entretanto, a influência da aderência graute/ bloco cerâmico no comportamento mecânico da alvenaria estrutural ainda é uma dúvida, visto que a NBR 15812 - 1 (ABNT, 2010) não especifica um valor de resistência para aderência graute/ bloco cerâmico, somente para graute/ aço. Frente a essa constatação, a presente pesquisa tem o objetivo de avaliar a influência da aderência graute/ bloco cerâmico estrutural no comportamento mecânico do conjunto, para determinar um valor de tensão de aderência que possa contribuir com a NBR 15812-1 (ABNT, 2010) Para isso, foram utilizados quatro tipos de blocos cerâmicos, com variação da geometria interna dos vazados e resistência mecânica à compressão. O graute foi padronizado em somente uma resistência, sendo essa de 30 MPa. Para desenvolvimento da pesquisa, inicialmente foi realizada a caracterização dos materiais e, posteriormente, realizados ensaios de push-out, resistência à compressão de blocos preenchidos com graute e microscopia óptica. Os resultados revelaram que a aderência graute/ bloco cerâmico estrutural é superior à resistência mecânica à tração do bloco cerâmico, e que a ruptura do conjunto ocorre primeiramente no bloco. Os resultados também constataram aumento da resistência mecânica à compressão axial nos blocos preenchidos com graute. / Currently, structural masonry is used in large-scale housing projects, in which the requirements of rationalization, control, speed and cost are better covered by the system. In Brazil there are projects of up to 16 floors built with high resistance and high technological control blocks. The construction of buildings with higher heights requires the increase of the capacity of absorption of compression and traction forces. For this, steel bars are inserted into hollow blocks which are then consolidated with grout in order to increase the load-bearing capacity of the assembly. However, the influence of ceramic block/grout adhesion in the mechanical behavior of structural masonry is still unknown since the NBR 15812-1 (ABNT, 2010) standard does not specify a resistance value for grout/ceramic block adhesion, only for grout/steel adhesion. In view of this finding, the present research has the objective of evaluating the influence of the structural ceramic block/grout adhesion on the mechanical behavior of the assembly in order to determine a value of adhesion tension that can contribute to the NBR 15812-1 (ABNT, 2010) standard For this purpose four types of ceramic blocks with a variation in the internal geometry of the hollow spaces and mechanical strength to compression were used. Grout was standardized in only one strength of 30 MPa. For development of the research, initially the characterization of the materials was performed and, subsequently, the tests of push-out and compressive strength of grout-filled blocks and light microscopy. The results showed that the grout/ceramic block adhesion is superior to the mechanical tensile strength of the ceramic block and, therefore, the rupture of the assembly will occur first in the block. The results also showed a significant increase of the mechanical resistance to axial compression in blocks filled with grout.
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Análise de diferentes metodologias executivas de solo pregado a partir de arrancamento realizados em campo e laboratório / Analysis of different soil nailing executive methods from pullout tests performed in field and laboratoryDanilo Pacheco e Silva 07 August 2009 (has links)
Apesar do largo emprego da técnica de solo pregado em nosso país, pouquíssima pesquisa foi realizada sobre a resistência ao cisalhamento de interface solo-reforço (qs) e sobre a importância deste parâmetro no desempenho desta técnica de reforço in situ de taludes e escavações. Busca-se com esta tese, avaliar experimentalmente, a influência de diferentes metodologias executivas do chumbador (número de injeções) neste parâmetro. As informações para o desenvolvimento deste trabalho foram obtidas a partir de ensaios de arrancamento realizados em chumbadores construídos em duas obras nas cercanias da cidade de São Paulo, ou seja, em escala real. De forma complementar, também foi construído uma estrutura de solo pregado em laboratório. A partir dos ensaios realizados, observaram-se melhorias significativas na resistência ao cisalhamento de interface a partir das injeções do chumbador e estabelecer equações que relacionam o valor de qs com o volume injetado de calda de cimento, sendo uma importante ferramenta para analisar o desempenho do chumbador. O monitoramento ao longo do ensaio permitiu analisar os mecanismos de distribuição das cargas. Por fim, é apresentada uma proposta de metodologia para a realização do controle de qualidade do chumbador. / Besides the soil nailing technique being common practice in Brazil, there is little research on the shear strength of the soil-reinforcement interface (qs) and on the importance of this parameter on the performance of this in situ reinforcement technique of slopes and excavations. Accordingly, this study has the objective to experimentally evaluate the influence of different executive methodologies of the nail (i.e. number of grout injections) on the parameter qs. Data were obtained from in situ, full scale pullout tests performed on nails built in two construction sites near Sao Paulo city. Additionally, a soil nailing structure was built in laboratory. The results show that significant improvement is achieved on the soil-nail interface shear strenght by the number of grout injections. Moreover, the pullout tests on the nails provided quantification of this improvement. Consequently, it was possible to establish equations that relate the value of qs to the volume of cement grout injected, which is as important tool to evaluate the performance of the nail. Monitoring of the instrumentation during execution of the pullout tests allowed evaluation of the mechanisms of load distribution along the nails. Finally, a methodology is proposed for a quality control procedure on soil-nailed walls.
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ANÁLISE DO COMPORTAMENTO DE PRISMAS GRAUTEADOS DE ALVENARIA ESTRUTURAL CERÂMICA / ANALYSIS OF THE BEHAVIOR OF GROUTED CLAY PRISMS FOR STRUCTURAL MASONRYGrohmann, Leandro Zampieri 24 February 2006 (has links)
The main purpose of this thesis is to evaluate the behavior of clay prisms
grouted, partially grouted and ungrouted under compression loads in order to
analyze the influence and performance of the grout, as well as to seek how to
optimize its applicability. For that, testing was done with different grouts and grouting
ratios.
The testing was done in 120 prisms under simple axial compression load,
where sets of prisms had two different types of mortar (A1 and A2), three different
grouts (G1, G2 e G3) and four different ratios of grouted cavities (0%, 33%, 66% e
100%). For this testing, all the materials and components were previously
characterized.
Based on experimental data, the analysis of the results was done taking into
account the different sets of prisms grouping them according to their mortar, grout
and grouting ratio. The variance analysis for the sample was done in order to prove
the existence of significant differences among the various group combinations. It was
also performed a comparison among the data found and results gathered by other
researchers.
Another investigation was done regarding the fracture behavior of prisms and
the influence of interactions among block, mortar and grout was observed.
Through the analysis of the results, some of the conclusions regarding the
behavior of prisms were: the importance of the mortar s strength for the compression
strength of the prisms; the increase in the strength of the grout does not indicate a
significant increase in the prisms strength; the significant increase in the prisms
strength is noticed only when the totality of the prisms cavities are grouted.
Overall, the use of masonry walls with partially grouted cavities is efficient if
properly used. For that, the types of grout and mortar must be suitable to and in
accordance with the mechanical behavior of the blocks used. / Este trabalho tem como objetivo principal avaliar o comportamento de prismas
de blocos cerâmicos grauteados, parcialmente grauteados e não-grauteados sob
a ação de cargas de compressão para que se possa analisar a influência e o
desempenho do graute e buscar sua otimização. Para tanto, foram realizados
ensaios experimentais de prismas com diferentes tipos de grautes e porcentagens
de grauteamento.
O método de pesquisa compreendeu o ensaio de compressão axial simples
de 120 prismas contrafiados de blocos cerâmicos com a utilização de dois tipos de
argamassa (A1 e A2), três tipos de grautes (G1, G2 e G3) e quatro diferentes
porcentagens de células grauteadas (0%, 33%, 66% e 100%), onde todos os
materiais e componentes empregados foram previamente caracterizados.
Com base nos dados experimentais foi realizada uma análise dos resultados
obtidos, por tipo de argamassa, tipo de graute e porcentagem de grauteamento
utilizados. Para comprovar a existência de diferenças significativas entre as várias
combinações de prismas ensaiados, foi feita a análise de variância da amostra
ensaiada. De posse destes resultados, foram feitas comparações com resultados
obtidos por outros autores.
Também observou-se, neste trabalho, os modos de ruptura dos prismas e foi
constatada a influência das interações entre bloco, argamassa e graute neste
comportamento.
Através da análise dos resultados pôde-se chegar a conclusões sobre o
comportamento dos prismas, como: a importância da resistência da argamassa na
resistência à compressão dos prismas; um aumento não significativo de resistência
dos prismas ao aumentar a resistência do graute; e um ganho efetivo de resistência
dos prismas somente ao terem a totalidade de suas células grauteadas.
De modo geral, conclui-se que a utilização do grauteamento parcial em
painéis de alvenaria é eficiente desde que seja utilizado de forma adequada,
havendo compatibilização da dosagem de traços de grautes e argamassas com as
características mecânicas dos blocos utilizados.
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RESISTÊNCIA À COMPRESSÃO DE PRISMAS PREENCHIDOS COM ARGAMASSA / GRAUTE / PRISMS MECHANICAL EVALUATION FILLED WITH MORTAR / GROUT THE COMPRESSIONMarco, Carlos Eduardo Giacomini de 10 March 2016 (has links)
This work has as main objective to analyze the mechanical behavior of prisms run
with ceramic bricks and filled with mortar or grout, checking their influence when
subjected to centric compression. An experimental program consists of four different
types of prisms was developed. They were used for making the prisms blocks of
three different Manufacturers. The ceramics were randomly named as Manufacturer
1 Manufacturer 2 and Manufacturer 3, manufacturers have provided the following
resistance of structural blocks: Manufacturer 1 - fbk (A) 6 MPa, Manufacturer 2 - fbk
(E) 7 MPa and fbk (C) 15 MPa Manufacturer 3 - FBK (B) and 6 MPa FBK (D) 15
MPa.The prisms were molded with industrialized mortar. Each prism type with its
respective resistors blocks were molded as follows: hollow prism, prisms filled with
grout (the larger castings), the same used in the settlement, and prisms filled with
grout, totaling 320 prisms, which were subjected to tests to simple axial compression.
The results were analyzed statistically by the Tukey test at 5% significance level. It
was concluded that the grout used not added significant increase in resistance to the
prisms, the study can not say whether it is possible or not to replace the grout by
mortar, to fill the cast, as well as adequate strength of the mortar used in filling It
should be further studied. / Este trabalho tem como objetivo principal analisar o comportamento mecânico de
prismas executados com blocos cerâmicos e preenchidos com argamassa ou
graute, verificando a sua influência quando submetidos à compressão centrada. Foi
desenvolvido um programa experimental composto por quatro diferentes tipos de
prismas. Foram utilizados para confecção dos prismas blocos de três diferentes
cerâmicas. As cerâmicas foram nomeadas aleatoriamente como Fabricante 1,
Fabricante 2 e Fabricante 3. Os fabricantes forneceram as seguintes resistências de
Blocos Estruturais: Fabricante 1 fbk(A) 6 MPa, Fabricante 2 fbk(E) 7 MPa e fbk(C) 15
MPa, Fabricante 3 fbk(B) 6 MPa e fbk(D) 15 MPa. Os prismas foram moldados com
argamassa industrializada. Cada tipo de prisma, com suas respectivas resistências
de blocos, foi moldado da seguinte forma: prismas ocos, prismas preenchidos com
argamassa (nos vazados maiores), a mesma utilizada no assentamento; e prismas
preenchidos com graute, totalizando 320 prismas, os quais foram submetidos a
ensaios à compressão axial simples.Os resultados foram analisados
estatisticamente através do Teste de Tukey com nível de significância de 5%.
Concluiu-se que o graute utilizado não agregou significativo acréscimo de resistência
aos prismas. Pelo estudo realizado não se pode afirmar se é possível ou não
substituir o graute pela argamassa, no preenchimento dos vazados, assim como a
resistência adequada da argamassa com uso no preenchimento deve ser
novamente estudada.
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On the Role of the Pore Water Chemistry of Deficient Post-Tension Grout to Promote Steel CorrosionPermeh, Samanbar 30 March 2016 (has links)
Corrosion failure of post-tension tendons with pre-packaged thixotropic grout was documented in Florida Bridges in less than 10 years of service. Analysis of deficient grout in Florida post-tensioned (PT) bridges where severe corrosion developed indicated enhanced sulfate ion concentration, high pore water pH, enhanced moisture and low chloride content. The corrosion wasn’t consistent with the conventional causes of steel corrosion such as bleed water accumulation in grout void spaces, chloride contamination and pore water carbonation. Corrosion development was associated with deficient grout with enhanced sulfate levels. However, limited information is available on the corrosion behavior of PT strand in grout materials with enhanced sulfate content. Review of the technical literature has not shown consistent evidence of the role of sulfate ions in the corrosion of steel in solution and in hydrated cementitious material. In this research, the role of sulfates in cementitous materials was examined including identifying practical limits for sulfates in grout materials.
Laboratory samples were created with 15% and 20% excess water to enhance deficient grout materials and included enhanced sodium and chloride content. Enhanced sulfate and chloride ion presence was thought to provide aggressive corrosion condition of steel in segregated grout. Testing was intended to differentiate the corrosion of steel in pore water condition of deficient grout.
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Experimental Evaluation of the Effects of Dynamic Pressure on Improving Cement-based Grout Penetrability : A study performed with the short slotMentesidis, Anastasios January 2015 (has links)
The increasing need for watertight underground works, such as tunnel excavations, has sparked an interest in a number of research studies with grout penetrability being the focus. The research has so far contributed to a deeper understanding regarding the assessment of a successful grouting operation from different perspectives such as choice of equipment, material properties, phase planning and performance. It is well established that several crucial factors influence the penetrability of grouts with pressure type and magnitude being two of them. Researchers have examined this issue from different perspectives and with different instruments. Previous research has shown that the increase of pressure has yielded better grout penetration both in the laboratory and the field. According to studies that dealt with dynamic pressure application, superimposed oscillatory pressure of high frequency resulted in grouts with decreased viscosity and better penetration. However, there is still need for further investigation in terms of lower frequencies, different pressure profiles and magnitudes and possible alternatives regarding the filtration and erosion mechanism. The present study aims to examine the penetrability of grouts under dynamic conditions of predefined peak and rest pressure intervals with frequencies lower than 0.5 Hz. The mechanism of action assumes active decomposition of any partially built plug in the vicinity of a narrowing in a rock fracture caused by the change in flow type before the constriction. The chosen method included the development of a laboratory grout injection system with a pneumatic valve and a pressure control rig. Tests were performed with both constant and varying pressure utilizing different periods of peak and rest intervals. The results showed an overall improvement of penetrability under dynamic conditions compared to the static. The decrease in peak – rest durations from [2 – 2] to [4 – 8] s yielded almost 11 times more material penetrating the 30μm aperture size. The developed method utilized a pneumatic injection system which culminated in better penetration when tuned at [2 – 2] s of [peak – rest] durations with specific material properties. This study presents an indication that further research towards the direction of dynamic pressure application could be proven beneficial in the grouting industry.
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Evaluating and Comparing of Three Penetrability Measuring Devices : Modified Filter Pump, Modified Penetrability Meter, and Short SlotAli Akbar, Saman, Al-Naddaf, Manar January 2015 (has links)
Rock grouting is a commonly used process for sealing rocks in tunnels to reduce water ingress. In order to achieve sufficient sealing level the grout must effectively penetrate into rock fractures while the limiting factor is filtration of cement based grout. Many devices and measuring methods have been developed to study filtration and to measure the penetrability. The filter pump and the penetrability meter are two of the most commonly used instruments for measuring filtration tendency in the field and in the lab, while short slot is used mainly in the lab. The results obtained from these devices have relatively different estimations of the penetrability partly due to the weaknesses in measuring methods and test procedures. Furthermore, there are no clear criteria to find out which of the results are closer to the reality or how much the results differ among these instruments. The aim of this study is comparing, and evaluating the results of these devices in relatively similar conditions while using more accurate methods of weight-time and pressure-time compared to the less reliable total volume method. The filter pump and the penetrability meter were modified In order to fulfill the requirement of testing in similar conditions and to improve their accuracy and versatility. The results show that increasing the pressure improves the penetrability significantly. The modification of the filter pump results in reducing many uncertainties related to the testing procedure. Probably the modified filter pump has higher accuracy in measuring the penetrability compared to regular filter pump. The short slot has the highest accuracy in estimating penetrability of cement based grout especially at higher pressures, furthermore, the short slot provides a more flexible way to measure penetrability with different pressures in the range of 1-15 bars.
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Geomechanical testing of non-hardening grout : for determination of flowability and strength propertiesBarrdahl, Axel January 2022 (has links)
Due to an increasing amount of aging tendencies in Swedish embankment dams, failures such as internal erosion has become a more common problem. Internal erosion is a phenomenon where certain soil material within the embankment dam is removed, often over a longer period of time. It is most common to occur at the inner core of the dam, and if it is allowed to continue for a longer time period the consequences can be disastrous. During the internal erosion, the inner material is washed out, creating larger voids and lowering the geotechnical stability of the dam. When larger voids start to appear, the seepage will increase allowing more material to be washed out and accelerating the process. In order to repair an embankment dam, exposed to inner erosion, it requires both the location of the faults as well as a suitable method of repairing. A method to repair internal erosion is by using grout and injecting it into the location of the fault. The knowledge regarding what type of grout and how it should be treated is today lacking. There are reasons to believe that a hardening mixture within an embankment dam using a till core will not cooperate well. For that reason, a grout with non-hardening properties is of interest. this thesis focuses on the Geomechanical strength parameters of two similar experimental non-hardening grouts. One with maximum grain size of 2 mm referred as grout 0/2, and one with maximum grain size of 4 mm, referred to as grout 0/4. The grouts consist of natural aggregates, calcium carbonate, water, bentonite, superplasticizer and defoamer. The grouts are evaluated by its undrained shear strength, water content, bulk- and dry density using fall cone tests and uniaxial compressive strength tests. To evaluate the grouts angle of friction and angle of dilatancy together with young’s modulus, consolidated, drained triaxial tests were performed. Three tests with different consolidation pressures (50, 150 and 300 kPa) were performed for each grout. Since the grout will gain strength with time, the tests have been performed after certain number of days in order to see the development of the grouts. The laboratories stretch from 0 to 112 days since the time of mixing the grout, and was performed at Luleå University of technology. Fall cone tests showed that the grout should most likely be mixed on site and left unstirred. Continuously stirring the grout quickly removed the grouts flowability which is why longer transportation should be avoided. At the same time, the accuracy of the grouts mixing is very demanding which needs to be taken into consideration. Triaxial tests showed that the grout 0/2 had dilatant behavior for 50 and 150 kPa consolidation pressure while 300 kPa showed contractive behavior. The grout 0/4 had dilatant behavior for 50 kPa consolidation pressure while 150 and 300 kPa showed contractive behavior. A theory to explain this behavior was constructed where the bentonite is believed to be behind it. Bentonite slurries behave as a Bingham fluid, where it requires a certain amount of shear stress for the fluid to start to flow. With the same reasoning, the low consolidation pressures do not exceed that threshold, resulting in dilatant behavior. But once that threshold is surpassed the grout starts to contract. In addition, flow curve tests were performed for additives, superplasticizer and defoamer. Both these substances showed Newtonian behavior which leaves Bentonite to be the only additive with Binghamian behavior. / På grund av en ökad mängd med föråldrandetendenser hos svenska jordfyllningsdammar har brott så som inre erosion blivit ett alltmer vanligt problem. Inre erosion är ett fenomen där en viss jord inom jordfyllningsdammen är avlägsnad, generellt över en längre tidsperiod. Oftast inträffar detta vid den inre damkärnan och om erosionen är tillåten att fortskrida sig över en längre period kan konsekvenserna bli förödande. Inre erosion fungerar så att jordmaterial tvättas ut vilket skapar hålutrymmen och minskar den geotekniska hållfastheten för dammen. När större hålutrymmen bildats ökar läckaget som i sin tur tillåter mer material att bli urtvättat och processen blir accelererad. För att kunna reparera en jordfyllningsdam, utsatt för inre erosion, krävs både att platsen för brottet och metoden för att reparera är kända. En metod för att reparera inre erosion är genom att använda injektering och injektera hålutrymmet. Dock är kunskapen gällande vad för typ av injektering och hur den ska hanteras icke existerande i dagsläget. Det finns anledning att tro att ett härdande bruk inom en jordfyllningsdam, med en moränkärna, inte kommer samarbeta särskilt bra. På grund av det har ett bruk med icke-härdande egenskaper undersökt. Den här uppsatsen fokuserar på de geotekniska hållfasthetsegenskaperna för två liknande experimentella icke-härdande bruk. Ett med maximal kornstorlek på 2 mm benämnd som bruk 0/2 och ett med maximal kornstorlek på 4 mm, benämnd som bruk 0/4. Bruket består av natursand, kalciumkarbonat, vatten, bentonit, mjukgöringsmedel och skumdämpare. Bruken är utvärderade genom deras odränerade skjuvhållfasthet, vattenkvot, skrym- och torrdensiteten som har tagits fram från fallkorns-test och enaxiella trycktest (UCS). För att utvärdera brukens friktionsvinkel och dilationsvinkel tillsammans med styvheten (initiella och 50 %) har konsoliderat, dränerat triaxiala tests utförts. Tre test med varierande konsolideringstryck (50, 150 och 300 kPa) har utförts för båda bruken. I och med att brukens hållfasthet kommer att öka med tiden, har testerna utförts efter ett visst antal dagar, för att se hur utvecklingen ser ut. Laborationerna har sträckt sig från 0 till 112 dagar sedan det att bruken har blandats, och utfördes vid Luleå Tekniska Universitet. Fallkornstesten visade att bruken bör med största sannolikhet blandas på arbetsplatsen och därefter förbli orörda. Kontinuerlig omrörning visade sig frånta brukens flytförmåga, vilket också är anledning till varför längre transporter bör undvikas. Samtidigt så är noggrannheten vid brukens blandning krävande vilket bör tas i beaktning. De triaxiala tester visade att bruk 0/2 visade ett dilatant beteende för både 50 och 150 kPa konsolideringstryck medan 300 kPa hade ett kontrakterande beteende. Bruket 0/4 hade dilatant beteende för 50 kPa konsolideringstryck medan 150 och 300 kPa visade kontrakterande beteende. En teori för att förklara detta beteende togs fram där bentoniten är den troliga orsaken. Bentonitblandningar (bentonite slurry) beter sig som en Bingham-vätska, där det krävs en viss mängd skjuvspänning för att få vätskan att börja flyta. Med samma resonemang applicerade på bruken innebar det att de låga konsolideringstrycken inte översteg tröskelvärdet, vilket resulterade i ett dilatant beteende. Däremot, när tröskelvärdet väl är överstiget börjar bruket att kontraktera istället. Det gjordes även flödestester på tillsatsmedlen, mjukgöringsmedel och skumdämpare. Testerna visade att båda medel betedde sig Newtoniskt, vilket lämnar bentoniten som det enda tillsatsmedlet med Bingham-beteende.
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