Dissertations / Theses on the topic 'Reinforced concrete, fibre'

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1

Deveau, Adrien Joseph. "Fibre-reinforced expansive concrete." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0019/MQ45858.pdf.

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2

Baczkowski, Bartlomiej Jan. "Steel fibre reinforced concrete coupling beams /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202007%20BACZKO.

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3

Armstrong, Paul John. "Projectile penetration into fibre reinforced concrete." Thesis, University of Sheffield, 1987. http://etheses.whiterose.ac.uk/10217/.

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A wide range of fibre reinforced concretes, potentially capable of sprayed application, and which could be used for protecting buildings, has been tested. Specimens 450mm square have been impacted by 7.62mm A. P. projectiles, and the damage assessed in terms of penetration path lengths within the specimens and the volume of the impact face spall crater. It has been found that inclusion of fibres does not increase the penetration resistance, but a small proportion of fibres significantly reduces the impact face spalling. The mechanisms of penetration and spalling have been examined using high speed photographic techniques and instrumented specimens.
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4

Barris, Peña Cristina. "Serviceability behaviour of fibre reinforced polymer reinforced concrete beams." Doctoral thesis, Universitat de Girona, 2011. http://hdl.handle.net/10803/7772.

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El uso de materiales compuestos de matriz polimérica (FRP) emerge como alternativa al hormigón convencionalmente armado con acero debido a la mayor resistencia a la corrosión de dichos materiales. El presente estudio investiga el comportamiento en servicio de vigas de hormigón armadas con barras de FRP mediante un análisis teórico y experimental. Se presentan los resultados experimentales de veintiséis vigas de hormigón armadas con barras de material compuesto de fibra de vidrio (GFRP) y una armada con acero, todas ellas ensayadas a flexión de cuatro puntos. Los resultados experimentales son analizados y comparados con algunos de los modelos de predicción más significativos de flechas y fisuración, observándose, en general, una predicción adecuada del comportamiento experimental hasta cargas de servicio. El análisis de sección fisurada (CSA) estima la carga última con precisión, aunque se registra un incremento de la flecha experimental para cargas superiores a las de servicio. Esta diferencia se atribuye a la influencia de las deformaciones por esfuerzo cortante y se calcula experimentalmente.
Se presentan los aspectos principales que influyen en los estados límites de servicio: tensiones de los materiales, ancho máximo de fisura y flecha máxima permitida. Se presenta una metodología para el diseño de dichos elementos bajo las condiciones de servicio. El procedimiento presentado permite optimizar las dimensiones de la sección respecto a metodologías más generales.
Fibre reinforced polymer (FRP) bars have emerged as an alternative to steel for reinforced concrete (RC) elements in aggressive environments due to their non-corrosive properties. This study investigates the short-term serviceability behaviour of FRP RC beams through theoretical and experimental analysis. Twenty-six RC beams reinforced with glass-FRP (GFRP) and one steel RC beam are tested under four-point loading. The experimental results are discussed and compared to some of the most representative prediction models of deflections and cracking for steel and FRP RC finding that prediction models generally provide adequate values up to the service load. Additionally, cracked section analysis (CSA) is used to analyse the flexural behaviour of the specimens until failure. CSA estimates the ultimate load with accuracy, but it underestimates the experimental deflection beyond the service load level. This increment is mainly attributed in this work to shear induced deflection and it is experimentally calculated.
A discussion on the main aspects of the SLS of FRP RC is introduced: the stresses in materials, maximum crack width and the allowable deflection. A methodology for the design of FRP RC at the serviceability requirements is presented, which allows optimizing the overall depth of the element with respect to more generalised methodologies.
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5

Al-Azzawi, Bakr. "Fatigue of reinforced concrete beams retrofitted with ultra-high performance fibre- reinforced concrete." Thesis, Cardiff University, 2018. http://orca.cf.ac.uk/108101/.

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Concrete structures deteriorate over time due to different reasons and thus may not perform their function satisfactorily. Repair and rehabilitation of deteriorated concrete structures is often preferred over demolition and rebuilding for economic reasons. Various metallic and nonmetallic materials have been used in the past for repair and rehabilitation. These materials have advantages and disadvantages. The latter are connected with the mismatch in the properties of these materials with the material of the structure being repaired which often resulted in unwanted failure modes, e.g. delamination. For this reason, new cement-based ultra-high performance reinforced with steel fibres repair materials have been developed in the last two decades, which restore (and even enhance) the structural response and improve the durability of repaired concrete structures. One such ultra-high-performance fibre-reinforced concrete material is CARDIFRC. It is characterized by very high compressive strength, high tensile /flexural strength, and high energy-absorption capacity. However, it is very expensive and thus industrially uncompetitive due to the very high cost of thin brass-coated steel fibres used in it. It is therefore important to develop a version of CARDIFRC that is industrially competitive. This is one of the objectives of this research. An ultra-high-performance fibre-reinforced concrete (UHPFRC) has been developed that is far less expensive than CARDIFRC and at the same time self-compacting. The steps necessary to achieve this have been described in this work. In addition, a full mechanical and fracture characterisation (i.e. size-independent fracture energy and the corresponding bi-linear stress-crack opening relationship) of this UHPFRC is presented. A nonlinear cracked hinge model has been used to back calculate the stress-crack opening relation of this material in an inverse manner from the test data. The second objective of this research concerns the flexural fatigue behaviour of this new UHPFRC. Tests have been conducted under several stress amplitude ranges. It has been found that the distribution of fibres plays a vital role in its fatigue resistance. Regions with few or no fibres can drastically reduce its fatigue life. As expected, non-zero mean stress leads to a significant reduction in the fatigue life of a material compared to cyclic loading with zero mean. The variation in compliance during cyclic loading has been used to estimate the expected fatigue life under a given cyclic load range, since the tests were terminated at one million cycles. The third objective of this research concerns the flexural fatigue behaviour of RC beams retrofitted with precast strips of this self-compacting UHPFRC on the tension face. Fatigue tests under several stress amplitude ranges have shown that this UHPFRC is an excellent retrofit material under fatigue loading. Again, the variation in compliance during the fatigue loading has been used to estimate the expected fatigue life for retrofitted RC beams.
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6

Babafemi, Adewumi John. "Tensile creep of cracked macro synthetic fibre reinforced concrete." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96679.

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Thesis (PhD)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Macro synthetic fibres are known to significantly improve the toughness and energy absorption capacity of conventional concrete in the short term. However, since macro synthetic fibre are flexible and have relatively low modulus of elastic compared to steel fibres, it is uncertain if the improved toughness and energy absorption could be sustained over a long time, particularly under sustained tensile loadings. The main goal of this study is to investigate the time-dependent crack mouth opening response of macro synthetic fibre reinforced concrete (FRC) under sustained uniaxial tensile loadings, and to simulate the flexural creep behaviour. For the purpose of simulating the in-service time-dependent condition, all specimens were pre-cracked. Experimental investigations were carried out at three levels (macro, single fibre and structural) to investigate the time-dependent behaviour and the mechanisms causing it. At the macro level, compressive strength, uniaxial tensile strength and uniaxial tensile creep test at 30 % to 70 % stress levels of the average residual tensile strength were performed. To understand the mechanism causing the time-dependent response, fibre tensile test, single fibre pullout rate test, time-dependent fibre pullout test and fibre creep test were done. Flexural test and flexural creep test were done to simulate the structural level performance. The results of this investigation have shown significant drop in stress and increase in crack width of uniaxial tensile specimens after the first crack. The post cracking response has shown significant toughness and energy absorption capacity. Under sustained load at different stress levels, significant crack opening has been recorded for a period of 8 month even at a low stress level of 30 %. Creep fracture of specimens occurred at 60 % and 70 % indicating that these stress levels are not sustainable for cracked macro synthetic FRC. The single fibre level investigations have revealed two mechanisms responsible for the time-dependent crack widening of cracked macro synthetic FRC under sustained loading: time-dependent fibre pullout and fibre creep. In all cases of investigation, fibre failure was by complete pullout without rupture. Flexural creep results have shown that the crack opening increases over time. After 8 months of investigation, the total crack opening was 0.2 mm and 0.5 mm at 30 % and 50 % stress levels respectively. Since the crack opening of tensile creep and flexural creep specimens cannot be compared due to differences in geometry, specimen size, load transfer mechanisms and stress distribution in the cracked plane, a finite element analysis (FEA) was conducted. Material model parameters obtained from the uniaxial tensile test and viscoelastic parameters from curve fitting to experimental uniaxial creep results have been implemented to successfully predict the time-dependent crack opening of specimens subjected to sustained flexural loading. Analyses results correspond well with experimental result at both 30 % and 50 % stress levels.
AFRIKAANSE OPSOMMING: Makro sintetiese vesels is bekend daarvoor dat dit die taaiheid en energie absorpsie van konvensionele beton beduidend verbeter in die kort termyn. Aangesien makro sintetiese vesels buigsaam is met 'n relatiewe lae styfheidsmodulus in vergeleke met staalvesels, is dit onseker of die verhoogde kapasiteit vir energie absorpsie en taaiheid volgehou kan word oor die langer termyn, veral in gevalle waar dit aan volgehoue trekkragte blootgestel is. Die hoofdoel van die studie is om die tydafhanklike-kraakvergrotingsgedrag van makro sintetiese veselversterkte beton (VVB) wat blootgestel is aan volgehoue trekkragte te ondersoek asook die simulasie van die kruipgedrag in buig. Ten einde die werklike toetstande te simuleer is al die proefstukke doelbewus gekraak in 'n beheerde manier voor die aanvang van die toetse. Die eksperimentele ondersoek is uitgevoer op drie vlakke (makro, enkelvesel en strukturele) om die tydafhanklike gedrag sowel as die meganismes verantwoordelik vir hierdie gedrag te ondersoek. Op die makro-vlak is druktoetse gedoen saam met eenassige trek- en eenassige kruiptoetse met belastings tussen 30 % en 70 % van die gemiddelde residuele treksterkte. Om die meganisme wat die tydafhanklike gedrag veroorsaak te verstaan is veseltoetse, enkel vesel uittrektoetse, enkel vesel uittrek kruiptoetse asook kruiptoetse op vesels gedoen. Buigtoetse en buig kruiptoetse is ook gedoen om die gedrag op die strukturele vlak te ondersoek. Die resultate van hierdie ondersoek wys dat daar 'n beduidende val in spanning is en dat daar gepaardgaande kraak opening in die eenassige trek proefstukke plaasgevind het na die vorming van 'n kraak. Die na-kraak gedrag wys beduidende taaiheid en energie absorpsie kapasiteit. Gedurende die volgehoue trekbelasting by verskillende spanningsvlakke is beduidende kraakvergroting opgemerk, selfs by 30 % belasting na 8 maande. Kruipfaling het plaasgevind by proefstukke met belastings van 60 % en 70 % wat daarop wys dat hierdie spanningsvlakke nie geskik is vir gekraakte makro sintetiese VVB nie. Op die enkel veselvlak is twee meganismes geïdentifiseer wat verantwoordelik is vir die kraakvergroting oor tyd vir gekraakte makro sintetiese VVB met volgehoue trekbelasting: tydafhanklike vesel uittrek en vesel-kruip. In alle gevalle in hierdie ondersoek was die falingsmeganisme vesels wat uittrek. Buig kruiptoets resultate wys dat die krake vergroot oor tyd. Na 8 maande van ondersoek was die kraakwydtes 0.2 mm en 0.5 mm by 30 % en 50 % spanningsvlakke onderskeidelik. Aangesien die kraak opening van eenassige trek kruiptoetse en die buig kruiptoetse nie direk met mekaar vergelyk kan word nie weens die verskille in geometrie, proefstuk grootte en spanningsverdeling in die kraakvlak, is 'n eindige element analises (EEA) gedoen. Materiaal eienskappe is bepaal deur gebruik te maak van die eenassige kruip trektoets se resultate en viskoelastiese parameters is bepaal deur middel van kurwepassing van die resultate. Dit was gebruik om suksesvol die buig kruip kraak opening gedrag te simuleer. Die analises se resultate vergelyk goed met die eksperimentele data by beide 30 % en 50 % spanningsvlakke.
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7

Kahanji, Charles. "Fire performance of ultra-high performance fibre reinforced concrete beams." Thesis, Ulster University, 2017. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709889.

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Ultra-high performance fibre reinforced concrete (UHPFRC) possesses favourable mechanical properties in comparison with normal strength concrete. Despite a surge in interest among researchers and industries over the past decade, there is negligible research data on the performance of UHPFRC in fire. This situation is compounded by the lack of design guidelines of UHPFRC in major structural design codes both at ambient and at elevated temperatures. The experimental work conducted was divided into three parts. The first part involved casting and testing of nine beams for flexure at ambient temperature. The beams were reinforced with steel fibres at 1, 2 and 4 vol. % and cured in two different conditions (20 °C and 90 °C water). In the second part, nine beams with two different steel fibre dosages (2 and 4 vol. %) were tested at elevated temperatures under an ISO 834 standard fire curve. Seven of these were tested while loaded at three different loading levels (0.2, 0.4 and 0.6). The other two, cured in different conditions, were tested unloaded at elevated temperatures to study the influence of the curing temperature. The third part involved determining the residual strength of the UHPFRC. The residual strength tests sought to investigate the influence of the curing temperature on the strength degradation of UHPFRC, with the aim of understanding the post-fire analysis and repairs. A finite element model was created using DIANA software followed by a parametric study. In the ambient temperature tests, the hot-cured beams recorded higher compressive strength. However, despite having lower compressive strength, the cold-cured beams had the higher load bearing capacity. Exposure of beams to fire was characterised with explosive spalling. Spalling was more prevalent in beams containing 2 vol. % of steel fibres. The beams under the 0.4 load level spalled significantly more than the other two load categories and had the least fire resistance. The addition of polypropylene fibres eliminated spalling and effectively increased the fire resistance of the beam. The curing temperature had an influence on the fire performance of the beams, the hot-cured beam spalled significantly more than the cold-cured. The findings from the residual strength tests indicated that the relative residual strength of cold-cured elements was higher than the hot-cured.
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8

Fisher, Alex K. "Durability design parameters for cellulose fibre reinforced concrete pipes in aggressive environments." Thesis, Queensland University of Technology, 2003.

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9

Badr, Atef Samir M. "Performance of advanced polypropylene fibre reinforced concrete." Thesis, University of Leeds, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.437106.

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10

Darwish, I. Y. S. "Steel fibre-reinforced concrete elements in shear." Thesis, Bucks New University, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375129.

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11

Vassou, Vassoulla. "Abrasion resistance of fibre reinforced concrete floors." Thesis, Aston University, 2003. http://publications.aston.ac.uk/14147/.

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This thesis focuses on the investigation of the abrasion resistance of fibre reinforced concrete floors at both the macro and micro levels. A literature review of the available literature concerning subjects allied to the current project is included. This highlights themes relevant to wear mechanisms and the factors influencing it: factors that affect the abrasion resistance of concrete and several test methods for assessing it; and the historical development of fibres and the properties of different fibre types and their influence on concrete. Three accelerated abrasion testers were compared and critically discussed for their suitability for assessing the abrasion resistance of concrete floors. Based on the experimental findings one accelerated abrasion apparatus was selected as more appropriate to be used for carrying out the main investigations. The laboratory programme that followed was undertaken to investigate the influence of various material and construction factors on abrasion resistance. These included mix variations (w/c ratio), fibre reinforcement, geometry, type and volume, curing method and superplasticizing agents. The results clearly show that these factors significantly affected abrasion resistance and several mechanisms were presumed to explain and better understand these observations. To verify and understand these mechanisms that are accountable for the breakdown of concrete slabs, the same concrete specimens that were used for the macro-study, were also subjected to microstructutural investigations using techniques such as Microhardness examination, Mercury intrusion porosimetry and Petrographic examination. It has been found that the abrasion resistance of concrete is primarily dependent on the microstructure and porosity of the concrete nearest to the surface. The feasibility of predicting the abrasion resistance of fibre reinforced concrete floors by indirect and non-destructive methods was investigated using five methods that have frequently been used for assessing the quality of concrete. They included the initial surface absorption test, the impact test, ball cratering, the scratch test and the base hardness test. The impact resistance (BRE screed tester) and scratch resistance (Base hardness tester) were found to be the most sensitive to factors affecting abrasion resistance and hence are considered to be the most appropriate testing techniques.
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Abdulmajid, Amin Ali Ahmed. "Strengthening of reinforced concrete beams using carbon fibre reinforced plastic." Thesis, Heriot-Watt University, 2007. http://hdl.handle.net/10399/1998.

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13

Elsaigh, Walied Ali Musa Hussien. "Modelling the behaviour of steel fibre reinforced concrete pavements." Pretoria : [s.n.], 2007. http://upetd.up.ac.za/thesis/available/etd-01292008-175515.

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14

Lau, Shuk-lei. "Rehabilitation of reinforced concrete beam-column joints using glass fibre reinforced polymer sheets." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B32001630.

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15

Fox, David Christopher Alexander. "The fire performance of restrained polymer-fibre-reinforced concrete composite slabs." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/17998.

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Composite slab flooring systems for steel-framed buildings consist of a profiled steel deck and a cast in-situ slab. The slab traditionally includes a layer of light gauge steel mesh reinforcement. This mesh is placed near the surface, which controls the early-age cracking caused by concrete drying and shrinkage. The steel mesh also performs a vital structural role at high temperatures. Structural fire tests and numerical investigations over the last 15 years have established that the mesh can provide enhanced fire resistance. A load-carrying mechanism occurs in fire with the mesh acting as a tensile catenary, spanning between perimeter supports. This structural mechanism is currently utilised regularly in the performance-based fire engineering design of steel-framed buildings. In a recent development, this mesh can be removed by using concrete with dispersed polymer fibre reinforcement to form the composite slab. The polymer-fibre-reinforced concrete (PFRC) is poured onto the deck as normal, and the fibres resist early crack development. For developers this technique has several advantages over traditional reinforcing mesh, such as lower steel costs, easier site operations and faster construction. However, to date the fire resistance of such slabs has been demonstrated only to a limited extent. Single element furnace tests with permissible deflection criteria have formed the basis for the fire design of such slabs. But these have not captured the full fire response of a structurally restrained fibre-reinforced slab in a continuous frame. The polymer fibres dispersed throughout the slab have a melting point of 160ºC, and it is unclear how they contribute to overall fire resistance. In particular, there has been no explanation of how such slabs interact with the structural perimeter to maintain robustness at high deflections. This project was designed to investigate the structural fire behaviour of restrained polymer-fibre-reinforced composite slabs. An experimental series of six slab experiments was designed to investigate the effects of fibre reinforcement and boundary restraint. A testing rig capable of recording the actions generated by the heat-affected slab was developed and constructed. Model-scale slab specimens were tested with different reinforcement and perimeter support conditions, to establish the contributions to fire resistance of the polymer fibres and applied structural restraint.
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Lau, Shuk-lei, and 劉淑妮. "Rehabilitation of reinforced concrete beam-column joints using glass fibre reinforced polymer sheets." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B32001630.

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17

Hall, Tara Stephanie. "Deflections of concrete members reinforced with fibre reinforced polymer, FRP, bars." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0016/MQ49676.pdf.

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18

Borhan, Tumadhir Merawi. "Thermal and structural behaviour of basalt fibre reinforced glass concrete." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/thermal-and-structural-behaviour-of-basalt-fibre-reinforced-glass-concrete(2fcc3a9a-2012-4261-966b-4ff37420e032).html.

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This study aims to produce a type of concrete with both good thermal and mechanical properties by using environmentally friendly and low cost materials. In addition, the resistance of this concrete to fire conditions was investigated. The experimental work comprises two parts. In the first part, recycled glass was used as a partial replacement for natural sand (at proportions 20%, 40% and 60%) together with basalt fibre having different volume fractions (0.1%, 0.3%, and 0.5%). The results obtained from the experimental work showed that the optimum content is 20% glass and at 28 days, there was a 4.23% and 15% enhancement in the compressive strength and the splitting tensile strength respectively. Above 20% glass there was a slight reduction (6.6% and 22%) in the compressive strength and the splitting tensile strength when 60% glass was used. The results also showed that when glass sand and basalt fibre content increase, there is a decrease in the thermal conductivity range from 4.35% to 50% at temperature levels between 60oC to 600oC. The structural behaviour of this type of concrete was investigated in the second part of this study by carrying out small-scale slab tests at ambient and elevated temperatures. The results show that there is an increase in the load carrying capacity above the theoretical yield line load, due to membrane action, for all percentages of glass and volume fractions of basalt fibre ranging from 1.35 to 1.68 for the slab tested at ambient temperature and from 3.13 to 3.26 for the slabs tested at elevated temperature. Also the slabs with higher glass sand and basalt fibre content had a higher load enhancement and failed at a higher displacement compared to the control mix.A comparison between the simplified method and the finite element software package ABAQUS showed that the ABAQUS model gives reasonable predictions for the load-vertical displacement and the temperature-displacement relationships at both ambient and elevated temperature conditions, while the simplified method gives conservative predictions for the maximum allowable vertical displacement for the slab at elevated temperature. A parametric study showed that a 10 mm cover depth is the optimum depth as well as the reinforcement temperature predicted reduced with increasing load ratio (applied load/yield line load).
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Ali, Ahsan. "Bond behavior of lightweight steel fibre-reinforced concrete." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2017. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-230104.

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This research was undertaken for studying the bond behaviour of Lightweight Fibre-reinforced Concrete (LWFC). Lightweight concrete is inherently weak in tension and has higher brittleness than the conventional concrete. To improve these and other properties, it is generally reinforced with deformed bars and fibres. There are number of studies that favour the use of Steel fibres, however such studies are mainly focused either on normal weight concrete or on the mechanical properties of different concretes. There are also different committee reports and in some cases specific sections of codes that specifically deal with the normal weight fibre-reinforced concrete. However, such is not the case with lightweight fibre-reinforced concrete; there is limited literature available especially on the Bond of lightweight fibre-reinforced concrete. In current research work effect of fibres is studied on the bond behaviour of the lightweight reinforced concrete. Since most of code provisions for bond are based on experimental work originally carried out on conventional concrete, effect of fibres on bond of conventional concrete was therefore also included in present research domain. Main bond tests were carried out using Pull-out test methodology. Test results indicate that the ultimate bond strength of conventional concrete when reinforced with steel fibres increased by 29%. However due to very low density and high porosity of lightweight aggregates, no significant improvement on bond strength of LWFC, as a result of fibres’ addition could be observed. Nevertheless, there is noteworthy improvement in the post-cracking bond strength of LWFC. Besides this, current bond-stress slip law as defined by Model Code 2010 does not reflect the positive effect of fibres, hence some modifications are suggested. It is also found that among the existing code expressions for estimation of bond strength, expression proposed by Model Code 2010 presents better results and its effectiveness can be further increased if fibre factor and factor for lightweight concrete are considered.
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Aoude, Hassan. "Structural behaviour of steel fibre reinforced concrete members." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18676.

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A series of full-scale axial compression tests was conducted on RC and SFRC columns. The specimens, which were detailed with varying amounts of transverse reinforcement, were cast using a self-consolidating concrete (SCC) mix that contained various quantities of fibres. The results demonstrate that the addition of fibres leads to improvements in load carrying capacity and post-peak response. The results also show that the addition of steel fibres can partially substitute for the transverse reinforcement in RC columns, thereby improving constructability while achieving significant confinement. Analytical models for the prediction of the load-strain response of SFRC columns are presented and validated with the experimental results. The tensile behaviour of SFRC members reinforced with a single reinforcing bar was also studied. The results indicate that the addition of fibres leads to improvements in tension stiffening and crack control. A procedure for predicting the response of tension members, accounting for the presence of fibres, is presented. Experimental investigations were carried out on a series of RC and SFRC beams. The effects of steel fibres on shear capacity, failure mechanism and crack control are studied. The results show that the addition of steel fibres leads to improvements in load carrying capacity and can lead to a more ductile failure. A simple procedure that can be used to predict the ultimate shear capacity of SFRC beams is introduced and validated using results from other researchers.
Une série d'essais a été réalisée sur des poteaux de taille réelle soumis à des charges axiales. Les échantillons, qui avaient des quantités variables d'armature transversale, ont été construits en utilisant un béton auto-plaçant qui contenait une quantité variable de fibres métalliques. Les résultants de cette étude expérimentale démontrent que la présence des fibres influence positivement la capacité portante des poteaux. De plus, les résultats montrent que l'utilisation d'un béton renforcé de fibres métalliques (BFM) peut s'avérer une solution appropriée pour assurer une ductilité adéquate aux poteaux. L'auteur propose des modèles analytiques pour prédire le comportement de poteaux chargés uniaxialement. Le comportement sous tension d'éléments en BFM armés d'une seule barre a été étudié. Les résultats montrent que la présence de fibres améliore la résistance en tension. Une procédure pour la prédiction de la réponse des éléments soumis sous tension, prenant en compte la présence de fibres métalliques, est présentée. Des recherches expérimentales furent entreprises afin d'étudier le comportement de poutres sans étriers. L'influence de la présence de fibres sur le développement de fissures ainsi que les mécanismes de ductilité et de rupture est discutée. Les résultats montrent que l'ajout de fibres améliore la capacité portante et la ductilité des poutres. Une procédure est suggérée afin de déterminer la capacité portante de poutres construits avec BFM.
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21

Le, Thanh Trung. "Ultra high performance fibre reinforced concrete paving flags." Thesis, University of Liverpool, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.502191.

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A literature survey on Ultra High Performance Fibre Reinforced Concrete (UHPFRC) reveals that the applications until now have remained limited. This is because although it has proved to have outstanding mechanical properties such. as the compressive strength of 150-250 MPa and flexural strength of 25-50 MPa, UHPFRC has a highcosting issue as well as shortage of mix design procedure and of structural design guidelines. Therefore, the following works are carried out in this PhD study. The mix design of UHPFRC is first studied. A mix design procedure based on the 'Excess Paste Model' is proposed to' design the preliminary mix proportions. The superplasticiser dosage and excess paste volume significantly influence the workability as well as the mechanical properties of UHPFRC. Optimisation of superplasticiser dosage and excess paste volume leads to the optimum mix proportions by reducing the water-binder ratio and finally enabling achievement of high strength. The by-products of industry such as Ground Granulated Blast-Furnace Slag (GGBS), Pulverised Fuel Ash (PFA), and glass cullet are studied to replace cement and silica sand in UHPFRC. These replacements help to reduce the cost. The replacement of cement by GGBS and PFA also lessens the environmental impact caused by the cement producing industry. The sustainability of UHPFRC is therefore improved. The mechanical properties of UHPFRC are investigated experimentally by testing cube specimens for compressive strength and prism specimens for flexural strength, fracture energy and flexural toughness. There is no significant difference of compressive strengths between two sizes of specimens, Le. 50 mm cube and 100 mm cube, but a considerable difference of flexural strengths between 40x40x160 mm specimens and 100x1 00x350 mm specimens is found. The origin of this size effect issue on flexural strength is therefore investigated by using different loading arrangements, extracting small specimens from large specimens, and various sizes and shapes of specimens. Two factors are found to contribute to this size effect. These are the boundary surface layer and the ratio of the total crack-surface area to the cross section area of beam specimens. Paving flags with the lower half of thickness comprising UHPFRC with 2.0% fibres are fabricated as an outcome product of the studies on mix proportions and mechanical properties. These 400x200x30 mm UHPFRC paving flags are cast using a 'Hydraulic press' technique replicating a factory's typical casting procedure. The flexural strength and fracture energy of UHPFRC paving flags are then examined to compare with those of ordinary concrete paving flags. These flexural strengths and fracture energies are used as input parameters for finite element analysis (FEA) models of pavements using these paving flags. The structural behaviour of pavements using ordinary concrete paving flags and pavements using UHPFRC paving flags positioned on sand bedding and sub-base layers are studied using both laboratory experiments and FEA models. The FEA model of UHPFRC pavement is then used to predict the structural behaviour when the thickness of flag, the thickness and elastic modulus of sub-base layer vary. The following novel and major outcomes from this PhD study contribute to the development of UHPFRC: • Systematic investigations of mix proportions and mechanical properties of UHPFRC help the users to select the raw materials, mix proportions and curing regime suitably for the structures required. The results on the effect of specimen size on the flexural behaviour of UHPFRC suggest that UHPFRC large-scale beams should be trialied carefully before use; • An application of UHPFRC for very high performance crack-resistant paving flags using in pedestrian pavements has been studied by both experimental and FEA methods. The potential benefits obtained from using UHPFRC paving flags compared with ordinary concrete paving flags include: (1) UHPFRC paving flags can be made thinner and lighter, resulting in the reduction of health and safety concerns during handling and placing and also the reduction in transportation costs; (2) increase of pavement service life and lead to reduced maintenance costs; (3) reduction of liability claims arising from uneven pavements.
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22

Jones, Peter A. "Flexural modelling of steel fibre reinforced sprayed concrete." Thesis, Loughborough University, 1998. https://dspace.lboro.ac.uk/2134/6885.

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A current limitation on the structural use of steel fibre reinforced sprayed concrete (that equally applies to cast steel fibre reinforced concrete) is a distinct lack of accepted design rationales and codes of practice. The research presented here describes the development of a model, based on conventional principles of mechanics, for predicting the flexure behaviour of a wet process sprayed concrete reinforced with deformed steel fibres. The model uses a stress-block diagram to represent the stresses (and resultant forces) that develop at a cracked section by three discrete stress zones: (a) a compressive zone; (b) an uncracked tensile zone; and (3) a cracked tensile zone. By using this concept it is shown that the stress-block diagram, and hence flexural behaviour, is a function of six principal parameters: the compressive stress-strain relation; the tensile stress-strain relation; fibre pull-out behaviour; the number and distribution of fibres across the crack in terms of their positions, orientations and embedment lengths; and the strain/crack-width profile in relation to the deflection of the beam. An experimental investigation was undertaken to obtain relationships for these parameters. Five tests were identified and developed as part of this investigation: a single fibre pull-out test; a compression test; a strain analysis test; a fibre distribution analysis test; and a flexural toughness test. The majority of the investigation used cast (as opposed to sprayed) specimens so that the test variables under investigation could be better controlled. Spraying trials were also successfully undertaken to demonstrate the pumpability and sprayability of the adopted mixes and to verify the use of the model for both cast and sprayed specimens. The results of the modelling analysis showed a reasonable agreement between the model predictions and experimental results in terms of the load-deflection response. However, the accuracy of the model is probably unacceptable for it to be currently used in design. A subsequent analysis highlighted the single fibre pull-out test and the sensitivity of the strain analysis tests as being the mai n cause of the discrepancies. As a result, recommendations are made for how the model might be improved. Overall this research has provided a valuable insight into the reinforcing mechanisms, fracture processes and characteristics of failure associated with the flexural behaviour of steel fibre reinforced concrete. It is envisaged that the proposed model could form the basis of a design rationale which requires only the matrix strength, fibre type, fibre content, beam size and loading geometry as design input parameters. Consequently, it could offer a much needed link between flexural toughness performance and structural design, by allowing designers to make informed choices regarding the mix design in order to meet the ultimate and serviceability requirements of a particular application.
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23

Hoy, Christopher W. "Mixing and mix proportioning of fibre reinforced concrete." Thesis, University of the West of Scotland, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.244006.

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24

Al-Tamimi, Adnan. "Fibre-reinforced connections in precast concrete flat slabs." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367112.

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25

Manarakis, George S. "Properties and applications of fresh fibre reinforced concrete." Thesis, University of Aberdeen, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262346.

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Concrete is possibly the most widely used man-made construction material in the world. Low cost, versatility and adequate compressive strengths are reasons for the popularity of concrete construction. In the present investigation various properties of polyproplene and steel fibre reinforced cementitious composites in their plastic state, which influence slipforming (Chapter 3), such as early age shrinkage (Chapters 4, 5) and uniaxial tensile strength (Chapter 6) are investigated, while properties of the same mixes in their hardened state such as compressive and tensile splitting strength are also determined (Chapter 9). Three new experimental apparatae were developed during this investigation - one for the determination of the tensile stress-strain curve of fresh concrete (Chapter 6) and two for the investigation of early age shrinkage cracking of fresh concrete (Chapter 7). Theoretical aspects relating to the obtained experimental results were also considered (Chapters 6, 8). The experimental data was analysed by a digital computer with the aid of five FORTAN 77 computer programmes which were written by the author specifically for this purpose (Chapter 10).
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26

Gurusamy, K. "The marine durability of steel fibre reinforced concrete." Thesis, University of Aberdeen, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234802.

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27

Jafarifar, Naeimeh. "Shrinkage behaviour of steel-fibre-reinforced-concrete pavements." Thesis, University of Sheffield, 2012. http://etheses.whiterose.ac.uk/7475/.

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The use of steel fibres extracted from waste tyres as reinforcement for concrete pavements has been developed at the University of Sheffield. The EU funded EcoLanes Project (Economical and sustainable pavement infrastructure for surface transport) undertook extensive research and developed solutions for Steel-Fibre-Reinforced-Concrete (SFRC) pavements with a particular focus on using recycled steel fibres and roller compacted concrete. The current research project ran alongside the EcoLanes project and aimed at contributing towards the development of design guidelines for pavements reinforced with recycled steel fibres. It was achieved through a study on the restrained shrinkage behaviour of Recycled-Steel-Fibre-Reinforced-Roller-Compacted-Concrete (R-SFR-RCC) pavements, and its consequent effect on the load bearing capacity and fatigue performance of pavements. The work in this thesis is mainly based on numerical investigations, but experiments were carried out to obtain the material properties (moisture transport, free shrinkage and mechanical). These basic physical properties were extracted from test results, using inverse analysis. The extent of distress induced by drying shrinkage was evaluated using moisture transport analysis coupled with stress analysis. The effect of shrinkage distress on the load bearing capacity of the pavement was investigated in a comparative way with and without shrinkage. Fatigue test results were also used to study the long-term load-bearing capacity. It was found that the rate of drying and consequent moisture diffusivity in SFRC is higher than for plain concrete and in RCC it is higher than for CC. Moisture diffusivity varies in the range of 0-5 mm2/day for moisture contents lower than 87-92% and then sharply increases to 30 mm2/day for saturated concrete. Free shrinkage is lower for SFRC compared with plain concrete, at early ages. RCC free shrinkage develops at a more uniform rate compared to CC. For the studied SFR-RCC pavement, surface micro-cracks are formed predominantly due to curling (with opening density of 0.69 mm/m) potentially forming micro-cracks (0.014 mm-0.056 mm width) spaced at 20 mm-60 mm. Cracking at the top surface initiates from the beginning of drying, and stabilises after 180 days. Shrinkage cracking penetrates down to around a quarter of the slab thickness, and the tensile strength at the top surface reduces 50% of the maximum strength; whereas based on the Concrete Society TR34, the strength reduces by 30% at the surface and drops linearly to zero at half depth. The current study found that the stress induced by curling is dominant, compared to that induced by external restraints. Shrinkage induced cracks was found to reduce the ultimate load bearing capacity and the fatigue capacity of the pavement by up to 50%.
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28

Funke, Henrik, Sandra Gelbrich, Lars Ulke-Winter, Lothar Kroll, and Carolin Petzoldt. "An application of asymmetrical glass fibre-reinforced plastics for the manufacture of curved fibre reinforced concrete." Universitätsbibliothek Chemnitz, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-178054.

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There was developed a novel technological and constructive approach for the low-cost production of curved freeform formworks, which allow the production of single and double-curved fibre reinforced concrete. The scheduled approach was based on a flexible, asymmetrical multi-layered formwork system, which consists of glass-fibre reinforced plastic (GFRP). By using of the unusual anisotropic structural behavior, these GFRP formwork elements permitted a specific adjustment of defined curvature. The system design of the developed GFRP formwork was examined exhaustively. There were designed, numerically computed and produced prototypical curved freeform surfaces with different curvature radii. The fibre reinforced concrete had a compressive strength of 101.4 MPa and a 3-point bending tensile strength of 17.41 MPa. Beyond that, it was ensured that the TRC had a high durability, which has been shown by the capillary suction of de-icing solution and freeze thaw test with a total amount of scaled material of 874 g/m² and a relative dynamic E-Modulus of 100% after 28 freeze-thaw cycles.
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29

Mahjoub-Moghaddas, Hamid. "Tensile and shear impact strength of concrete and fibre reinforced concrete." Thesis, Cardiff University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261439.

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30

Ahmed, Ehab Abdul-Mageed. "Shear behaviour of concrete beams reinforced with fibre-reinforced polymer (FRP) stirrups." Thèse, Université de Sherbrooke, 2009. http://savoirs.usherbrooke.ca/handle/11143/1903.

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Corrosion of steel reinforcement is a major cause of deterioration in reinforced concrete structures especially those exposed to harsh environmental conditions such as bridges, concrete pavements, and parking garages. The climatic conditions may have a hand in accelerating the corrosion process when large amounts of salts are used for ice removal during winter season. These conditions normally accelerate the need of costly repairs and may lead, ultimately, to catastrophic failure. Therefore, using the non-corrodible fibre-reinforced polymer (FRP) materials as an alternative reinforcement in prestressed and reinforced concrete structures is becoming a more accepted practice in structural members subjected to severe environmental exposure. This, in turn, eliminates the potential of corrosion and the associated deterioration. Stirrups for shear reinforcement normally enclose the longitudinal reinforcement and are thus the closest reinforcement to the outer concrete surface. Consequently, they are more susceptible to severe environmental conditions and may be subjected to related deterioration, which reduces the service life of the structure. Thus, replacing the conventional stirrups with the non-corrodible FRP ones is a promising aspect to provide more protection for structural members subjected to severe environmental exposure. However, from the design point of view, the direct replacement of steel with FRP bars is not possible due to various differences in the mechanical and physical properties of the FRP materials compared to steel. These differences include higher tensile strength, lower modulus of elasticity, different bond characteristics, and absence of a yielding plateau in the stress-strain relationships of FRP materials. Moreover, the use of FRP as shear reinforcement (stirrups) for concrete members has not been sufficiently explored to provide a rational model and satisfactory guidelines to predict the shear strength of concrete members reinforced with such type of stirrups. An experimental program to investigate the structural performance of FRP stirrups as shear reinforcement for concrete beams was conducted. The experimental program included seven large-scale T-beams reinforced with FRP and steel stirrups. Three beams were reinforced with CFRP stirrups, three beams reinforced with GFRP stirrups, and one beam reinforced with steel stirrups. The geometry of the T-beam was selected to simulate the New England Bulb Tee Beam (NEBT) that is being used by the Ministry of Transportation of Québec (MTQ), Canada. The beams were 7.0 m long with a T-shaped cross section measuring a total height of 700 mm, web width of 180 mm, flange width of 750 mm, and flange thickness of 85 mm. The large-scale T-beams were constructed using normal-strength concrete and tested in four-point bending over a clear span of 6.0 m till failure to investigate the modes of failure and the ultimate capacity of the FRP stirrups in beam action. The test variables considered in this investigation were the material of the stirrups, shear reinforcement ratio, and stirrup spacing. The specimens were designed to fail in shear to utilize the full capacity of the FRP stirrups. Six beams failed in shear due to FRP (carbon and glass) stirrup rupture or steel stirrup yielding. The seventh beam, reinforced with CFRP stirrups spaced at d /4, failed in flexure due to yielding of the longitudinal reinforcement followed by crushing of concrete. The effects of the different test parameters on the shear behaviour of the concrete beams reinforced with FRP stirrups were presented and discussed. The test results contributed to amending the shear provisions incorporated in the Canadian Highway Bridge Design Code (CAN/CSA-S6) and the updated provisions were approved in the CSA-S6-Addendum (CSA 2009). An analytical investigation was conducted to evaluate the validity and accuracy of available FRP codes and guidelines in Japan, Europe, and North America. The predictions of the codes and the guidelines were verified against the results of the tested beams as well as 24 other beams reinforced with FRP stirrups from the literature. The tested beams were also analysed using various shear theories including the modified compression field theory (MCFT), the shear friction model (SFM), and the unified shear strength model (USSM). A simple equation for predicting the shear crack width in concrete beams reinforced with FRP stirrups is proposed and verified against the experimentally measured values.
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31

Svecova, Dagmar Carleton University Dissertation Engineering Civil and Environmental. "Serviceability and strength of concrete parking structures reinforced by fibre-reinforced plastics." Ottawa, 1994.

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32

Al, Ajami Abdulhamid. "Punching shear of concrete flat slabs reinforced with fibre reinforced polymer bars." Thesis, University of Bradford, 2018. http://hdl.handle.net/10454/16864.

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Fibre reinforcement polymers (FRP) are non-corrodible materials used instead of conventional steel and have been approved to be an effective way to overcome corrosion problems. FRP, in most cases, can have a higher tensile strength, but a lower tensile modulus of elasticity compared to that of conventional steel bars. This study aimed to examine flat slab specimens reinforced with glass fibre reinforced polymer (GFRP) and steel bar materials for punching shear behaviour. Six full-scale two-way slab specimens were constructed and tested under concentric load up to failure. One of the main objectives is to study the effect of reinforcement spacing with the same reinforcement ratio on the punching shear strength. In addition, two other parameters were considered, namely, slab depth, and compressive strength of concrete. The punching shear provisions of two code of practises CSA S806 (Canadian Standards 2012) and JSCE (JSCE et al. 1997) reasonably predicted the load capacity of GFRP reinforced concrete flat slab, whereas, ACI 440 (ACI Committee 440 2015) showed very conservative load capacity prediction. On the other hand, a dynamic explicit solver in nonlinear finite element (FE) modelling is used to analyse a connection of column to concrete flat slabs reinforced with GFRP bars in terms of ultimate punching load. All FE modelling was performed in 3D with the appropriate adoption of element size and mesh. The numerical and experimental results were compared in order to evaluate the developed FE, aiming to predict the behaviour of punching shear in the concrete flat slab. In addition, a parametric study was created to explore the behaviour of GFRP reinforced concrete flat slab with three parameters, namely, concrete strength, shear load perimeter to effective depth ratio, and, flexural reinforcement ratio. It was concluded that the developed models could accurately capture the behaviour of GFRP reinforced concrete flat slabs subjected to a concentrated load. Artificial Neural Networks (ANN) is used in this research to predict punching shear strength, and the results were shown to match more closely with the experimental results. A parametric study was performed to investigate the effects of five parameters on punching shear capacity of GFRP reinforced concrete flat slab. The parametric investigation revealed that the effective depth has the most substantial impact on the load carrying capacity of the punching shear followed by reinforcement ratio, column perimeter, the compressive strength of the concrete, and, the elastic modulus of the reinforcement.
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33

Zaina, Mazen Said Civil &amp Environmental Engineering Faculty of Engineering UNSW. "Strength and ductility of fibre reinforced high strength concrete columns." Awarded by:University of New South Wales. School of Civil and Environmental Engineering, 2005. http://handle.unsw.edu.au/1959.4/22054.

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The main structural objectives in column design are strength and ductility. For higher strength concretes these design objectives are offset by generally poor concrete ductility and early spalling of the concrete cover. When fibres are added to the concrete the post peak characteristics are enhanced, both in tension and in compression. Most of the available experimental data, on fibre reinforced concrete and fibre reinforced high strength concrete columns, suggest that an improvement in both ductility and load carrying capacity due to the inclusion of the fibres. In this thesis the ductility and strength of fibre reinforced high strength concrete are investigated to evaluate the effect of the different parameters on the performance of columns. The investigation includes both experimental and the numerical approaches with 56 high strength fibre reinforced concrete columns being tested. The concrete strength ranged between 80 and 100 MPa and the columns were reinforced with 1, 2 or 2.6 percent, by weight, of end hooked steel fibres. The effect of corrugated Polypropylene fibres on the column performance was also examined. No early spalling of the cover was observed in any of the steel fibre reinforced column tested in this study. A numerical model was developed for analysis of fibre and non-fibre reinforced eccentrically loaded columns. The column is modelled as finite layers of reinforced concrete. Two types of layers are used, one to represent the hinged zone and the second the unloading portion of the column. As the concrete in the hinged layers goes beyond the peak for the stress verus strain in the concrete the section will continue to deform leading to a localised region within a column. The numerical model is compared with the test data and generally shows good correlation. Using the developed model, the parameters that affect ductility in fibre-reinforced high strength concrete columns are investigated and evaluated. A design model relating column ductility with confining pressure is proposed that includes the effects of the longitudinal reinforcement ratio, the loading eccentricity and the fibre properties and content and design recommendations are given.
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34

Øfsdahl, Ellen. "Fibre-reinforced Self-compacting Concrete : Prediction of Rheological Properties." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for konstruksjonsteknikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-18826.

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The purpose of this thesis is to investigate the relationship between measured rheology and proportioning properties with particular attention to maximum packing fraction, thickness of fiber lubricating matrix and fiber rotational overlap.This is done by conducting experiments on fresh concrete where the amount of matrix and fibres are varied, and comparing the rheological results with the proportioning parameters.The importance of an accurate grading curve is also evaluated.The hypothesis is that it is possible to find a correlation between calculated proportioning parameters and resulting rheology that will enable prediction of rheological properties.The results show that the variation in grading curve for the same aggregate is not very relevant to the proportioning parameters.The air content is shown to be of great importance regarding the correlation between matrix volume and packing fraction. Also it is found that it can be possible to predict the air volume based on matrix volume and fiber content.
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35

Wight, Raymond Gordon. "Strengthening concrete beams with prestressed fibre reinforced polymer sheets." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0007/NQ31960.pdf.

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36

Dunwoodie, David. "Seismic retrofit of bridge columns using fibre-reinforced concrete." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0007/MQ44005.pdf.

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37

Khalil, Ahmed Amir Ghobarah Ahmed. "Rehabilitation of reinforced concrete structural walls using fibre composites /." *McMaster only, 2005.

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38

Paine, Kevin Andrew. "Steel fibre reinforced concrete for prestressed hollow core slabs." Thesis, University of Nottingham, 1998. http://eprints.nottingham.ac.uk/11095/.

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An investigation of prestressed concrete containing steel fibres as secondary reinforcement to improve performance in shear, flexure and bond is reported. Emphasis is placed on the use of steel fibres in prestresssed extruded hollow core slabs, since these common precast elements have intrinsic difficulty in incorporating traditional secondary reinforcement due to their unique shape and manufacturing method. Two separate studies were carried out. The first study involved laboratory investigations into the bond between fibre reinforced concrete (FRC) and the prestressing strand, and the shear behaviour of laboratory-cast prestressed fibre reinforced concrete (PFRC) beams. The second part involved the factory production of fibre reinforced hollow core slabs in co-operation with a local manufacturer. The fibre reinforced hollow core slabs were subjected to conventional full-width shear tests, concentrated load shear tests, and to transverse flexure. For all laboratory cast elements, cubes, cylinders and prisms were cast to investigate compressive, tensile and flexural properties, respectively. Two types of steel fibre were investigated: hooked-end steel fibres at fibre volume fractions (Vf) of 0.5%, 1.0% and 1.5%; and amorphous metal fibres at Vf‘s of 0.28% and 0.56%. The trial production of fibre reinforced hollow core slabs necessitated the investigation of the effect of steel fibres on the extrusion manufacturing process. It was shown that fibre reinforced hollow core slabs could be adequately compacted with only slight increases in mixing water. Fibres were found to distribute randomly throughout the cross-section. However, the rotation of the augers affected the orientation of fibres, with fibres tending to align vertically in the web. It was shown that the addition of steel fibres to prestressed concrete has a negative effect on the bond between matrix and tendon, leading to longer transfer lengths. The effect of the increase in transfer length was to reduce cracking shear strengths by 4%. Shear tests showed that the incorporation of steel fibres could increase shear strength by as much as 45% for Vf = 1.5%. This increase in shear strength, known as the fibre contribution, was shown to be due to fibres bridging across the crack and an increased compressive resistance due to fibres arresting the propagation of cracks into the compressive zone. A semi-empirical equation for shear strength of PFRC elements is developed. It is given in two forms, one compatible with the present equations for prestressed concrete given in BS 8110 and Eurocode 2, and a second form compatible with that advocated for fibres in reinforced concrete. The equation makes use of equivalent flexural strength which is recognised as the most useful material property for design of FRC. The equation was found to give good correlation with the shear strength of single web beams cast both in the laboratory and under factory conditions. However, a overall strength reduction factor is required for full-width hollow core slabs to account for uneven load distribution and inconsistent web widths. This is consistent with tests on plain hollow core slabs found in the literature.
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39

Whitehead, Paul Arthur. "Shear strength of concrete containing fibre-reinforced-plastic reinforcement." Thesis, University of Bath, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275880.

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40

Oikonomou-Mpegetis, Sotirios. "Behaviour and design of steel fibre reinforced concrete slabs." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/23792.

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Using Steel Fibre Reinforced Concrete (SFRC) can bring substantial benefits to the construction industry of which savings in construction time and labour are most significant. In addition, steel fibres enhance crack control particularly when acting in conjunction with reinforcement bars. Despite the aforementioned benefits of SFRC, there is a still a lack of consensus on the principles that should be adopted in its design. Currently, a number of different test methods are used to determine the material properties of SFRC but there is no agreement on which method is best. As a result, steel fibre suppliers claim widely differing properties for similar fibres which leads to confusion amongst designers and in some cases inadequate structural performance. This research considers the design of SFRC slabs with emphasis on pile supported slabs which are frequently designed using proprietary methods due to the absence of codified guidance. Key issues in the design of such slabs are control of cracking in service and the calculation of flexural and punching shear resistances. A fundamental challenge is that SFRC exhibits a strain softening response at the dosages commonly used in slabs. At present, the yield line method is generally considered most suitable for designing such slabs at the ultimate limit state but there is a lack of consensus on the design moment of resistance as the bending moment along the yield lines reduces with increasing crack width. This thesis investigates these matters using a combination of experimental and theoretical work. The experimental work compares material properties derived from notched beam and round plate tests and seeks to determine a relationship between the two. Tests were also carried out on continuous slabs with the same material properties as used in the notched beam and round plate tests. Round plate tests were also carried out to determine the contribution of steel fibres to punching shear resistance. The theoretical work investigates the applicability of yield line analysis to the design of SFRC slabs using a combination of numerical modelling and design oriented analytical models. Design for punching shear and the serviceability limit state of cracking are also considered.
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41

Mouton, Christiaan Johannes. "Investigating the tensile creep of steel fibre reinforced concrete." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20355.

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Thesis (MScEng)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Research in concrete has advanced to such an extent that it is now possible to add steel fibres to concrete in order to improve its durability and ductility. This led to a research group in Europe, FIB, who has provided guidelines to designing Steel Fibre Reinforced Concrete (SFRC) structures. They have found that it is possible for SFRC beams in flexure to be in static equilibrium. However, the time-dependent behaviour of SFRC has not been researched fully and it requires further investigation. When looking at a concrete beam in flexure there are two main stress zones, the compression zone and the tension zone, of which the tensile zone will be of great interest. This study will report on the investigation of the tensile time-dependent behaviour of SFRC in order to determine how it differs from conventional concrete. The concrete has been designed specifically to exhibit strain-softening behaviour so that the material properties of SFRC could be investigated fully. Factors such as shrinkage and tensile creep of SFRC were of the greatest importance and an experimental test setup was designed in order to test the tensile creep of concrete in a simple and effective manner. Comparisons were be made between the tensile creep behaviour of conventional concrete and SFRC where emphasis was placed on the difference between SFRC specimens before and after cracking occurred in order to determine the influence of steel fibre pull-out. The addition of steel fibres significantly reduced the shrinkage and tensile creep of concrete when un-cracked. It was however found that the displacement of fibre pull-out completely overshadowed the tensile creep displacements of SFRC. It was necessary to investigate what effect this would have on the deflection of SFRC beams in flexure once cracked. Viscoelastic behaviour using Maxwell chains were used to model the behaviour of the tensile creep as found during the tests and the parameters of these models were used for further analyses. Finite Element Analyses were done on SFRC beams in flexure in order simulate creep behaviour of up to 30 years in order to determine the difference in deflections at mid-span between un-cracked and pre-cracked beams. The analyses done showed that the deflections of the pre-cracked SFRC beams surpassed the requirements of the Serviceability Limit States, which should be taken into account when designing SFRC beams.
AFRIKAANSE OPSOMMING: Die navorsing in beton het gevorder tot so ‘n mate dat dit nou al moontlik is om staal vesels by die beton te voeg sodat dit beton se duursaamheid en duktiliteit te verbeter. Dit het gelei tot ‘n groep in Europa, FIB, wat dit moontlik gemaak het om Staal Vesel Beton (SVB) strukture te ontwerp. Hulle het gevind dat dit moontlik is vir SVB balke om in statiese ewewig te wees tydens buiging. Die tyd afhanklike gedrag van SVB is egter nog nie deeglik ondersoek nie en benodig dus verdure ondersoek. Wanneer ‘n balk in buiging aanskou word kan twee hoof spanningzones identifiseer word, ‘n druk zone en ‘n trek zone, waarvan die trek zone van die grootste belang is. Hierdie studie gaan verslag lewer oor die ondersoek van tyd-afhanklike trekgedrag van SVB om te bepaal hoe dit verskil van konvensionele beton. Die beton was spesifiek ontwerp om vervormingsversagtende gedrag te wat maak dat die materiaal eienskappe van SVB ten volle ondersoek kan word. Faktore soos krimp en die trekkruip van SVB was van die grootste belang en ‘n eksperimentele toets opstelling was ontwerp om die trekkruip van beton op ‘n eenvoudige en effektiewe manier te toets. Daar was vergelykings getref tussen die trekkruip gedrag van konvensionele beton en SVP en groot klem was geplaas op die verskil tussen SVB monsters voor en na die monsters gekraak het om te bepaal wat die invloed was van staalvesels wat uittrek. Die byvoeging van staalvesels het beduidend die kruip en trekkruip van beton verminder. Daar was alhoewel gevind dat die verplasing van die uittrek van staalvesels heeltemal die trekkruip verplasings van SVB oorskadu het. Dit was nodig om te sien watse effek dit op die verplasing van SVB balke in buiging sal hê. Viskoelastiese gedrag deur Maxwell kettings was gebruik om die gedrag van trekkruip, soos gevind deur die toetse, te modelleer en die parameters van hierdie modelle was verder gebruik vir analises. Eindige Element Analises was gedoen op SVB balke in buiging om die trekkruip gedrag tot op 30 jaar te simuleer op die verskil tussen die defleksies by midspan tussen ongekraakte en vooraf gekraakte balke te vind. Die analises het gewys dat die defleksies van die vooraf gekraakte balke nie voldoen het aan die vereistes van die Diensbaarheid limiete nie, wat in ag geneem moet word wanneer SVB balke ontwerp word.
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42

Syed, Mohsin Sharifah Maszura Binti. "Behaviour of fibre-reinforced concrete structures under seismic loading." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/17804.

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The present research is concerned with the modelling of the structural behaviour of steel fibre-reinforced concrete (SFRC) using non-linear finite-element (FE) analysis. Key structural response indicators such as load-deflection curves, strength, stiffness, ductility, energy absorption and cracking were examined. In particular, the potential for fibres to substitute for a reduction in conventional transverse reinforcement was studied. Such reduction is highly desirables in practice as it helps alleviate reinforcement congestion, often experienced in the seismic detailing of critical regions such as beam-column joints. Thus two key parameters were considered, namely reducing transverse reinforcement while increasing the amount of fibres. The reduction in conventional reinforcement was achieved mainly by increasing stirrups spacing (and also by reducing double-hoop arrangement commonly used in seismic detailing of joints). The behaviour of SFRC structural elements was studied under both monotonic and reversed-cyclic loadings (the latter used to mimic seismic action). Emphasis was initially focused on the study of available experimental data describing the effect of steel fibres on the post-cracking response of concrete. Consequently the SFRC constitutive model proposed by Lok and Xiao (1999) was selected. The numerical model was calibrated against existing experimental data to ensure the reliability of the FE predictions. Subsequently, further analyses were carried out investigating three main case studies namely, simply supported beams, two-span continuous (i.e. statically-indeterminate) columns, and both exterior and interior beam-column joints. Parametric studies were carried out covering the full practical range of steel fibre dosages and appropriate amounts of reduction in conventional transverse reinforcement. The results show that steel fibres increase the load-carrying capacity and stiffness (thus enhancing response at both the serviceability and ultimate limit states, which are important design considerations). Fibres were found also to improve ductility (as well as altering the mode of failure from a brittle to a ductile one).
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43

Kölle, Boris. "Behaviour of steel fibre reinforced high performance concrete under biaxial loading conditions." Connect to e-thesis, 2006. http://theses.gla.ac.uk/715/.

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Thesis (Ph.D.) - University of Glasgow, 2006.
Ph.D. thesis submitted to the Department of Civil Engineering, University of Glasgow, 2006. Includes bibliographical references. Print version also available.
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44

Nofal, Mostafa. "Continuum damage mechanics for plain, fibre-reinforced, and reinforced concrete materials and structures." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ26860.pdf.

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45

Thorburn, Lorna Jane. "A study of externally reinforced fibre-reinforced concrete bridge decks on steel girders." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0028/NQ31536.pdf.

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46

Abdel-Jaber, Ma'en. "Shear strengthening of reinforced concrete beams using externally bonded carbon fibre reinforced plates." Thesis, Oxford Brookes University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341653.

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47

Lee, Stephen Kim Lon. "Flexural strength of reinforced concrete beams strengthened using carbon fibre reinforced composite sheets." Thesis, University of Southampton, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.420192.

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48

Triantafyllidis, Zafeirios. "Structural enhancements with fibre-reinforced epoxy intumescent coatings." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/29514.

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Epoxy intumescent coatings are fire protection systems for steel structural elements that are widely used in applications that protection from severe hydrocarbon fires is required, such as oil and gas facilities. These polymer coatings react upon heating and expand into a thick porous char layer that insulates the protected steel element. In the typical fire scenarios for these applications, the intumescent coatings must resist very high heat fluxes and highly erosive forces from ignited pressurised gases. Hence, continuous fibre reinforcement is embedded in the thick epoxy coating during installation, so as to ensure the integrity of the weak intumesced char during fire exposure. This reinforcement is typically in the form of a bidirectional carbon and/or glass fibre mesh, thus under normal service conditions a fibre-reinforced intumescent coating (FRIC) is essentially a lightly fibre-reinforced polymer (FRP) composite material. This thesis examines the impacts of embedded high strength fibres on the tensile behaviour of epoxy intumescent materials in their unreacted state prior to fire exposure, and the potential enhancements that arise in the structural performance of elements protected with FRICs. An experimental programme is presented comprising tensile coupon tests of unreacted intumescent epoxies, reinforced with different fibre meshes at various fibre volume fractions. It is demonstrated that the tensile properties of FRICs can be enhanced considerably by including increasing amounts of carbon fibre reinforcement aligned in the principal loading direction, which can be tailored in the desired orientation on the coated structural members to enhance their load carrying capacity and/or deformability. An experimental study is presented on coated intact and artificially damaged I-beams (simulating steel losses from corrosion) tested in bending, demonstrating that FRICs can enhance the flexural response of the beams after yielding of steel, until the tensile rupture of the coatings. An analytical procedure for predicting the flexural behaviour of the coated beams is discussed and validated against the obtained test results, whereas a parametric analysis is performed based on this analytical model to assess the effect of various parameters on the strengthening efficiency of FRICs. The results of this analysis demonstrate that it is feasible to increase the flexural load capacity of thin sections considerably utilising the flexural strength gains from FRICs. Finally, a novel application is proposed in this thesis for FRICs as a potential system for structural strengthening or retrofitting reinforced concrete and concrete-encased steel columns by lateral confinement. An experimental study is presented on the axial compressive behaviour of short, plain concrete and concrete-encased structural steel columns that are wrapped in the hoop direction with FRICs. The results clearly show that epoxy intumescent coatings reinforced with a carbon fibre mesh of suitable weight can provide lateral confinement to the concrete core resisting its lateral dilation, thus resulting in considerable enhancements of the axial strength and deformability of concrete. The observed strengthening performance of the composite protective coatings is found to be at least as good as that of FRP wraps consisting of the same fibre reinforcement mesh and a conventional, non-intumescent epoxy resin. The predictive ability of existing design-oriented FRP confinement models is compared against the experimental results, and is found to be reasonably precise in predicting the peak strength of the tested columns, hence existing models appear to be suitable for design and analysis of column strengthening schemes with the proposed novel FRIC system. The research presented herein shows clearly that FRICs have a strong potential as alternative systems for consideration in the field of structural strengthening and rehabilitation, since they can provide substantial enhancements in the load carrying capacity for both applications considered. At the same time FRICs can thermally protect the underlying structural elements in the event of a fire, by intumescing and charring, thus potentially eliminating the need for additional passive fire protection that is common with conventional fire-rated FRP wrapping systems. Although this thesis provides a proof-of-concept for use of the proposed novel FRICs as structural strengthening materials, considerable additional research is particularly required to study their fire protection performance when applied to concrete substrates, to make use of the proposed hybrid functionality with confidence.
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49

Carlesso, Débora Martinello. "Flexural fatigue of pre-cracked fibre reinforced concrete: experimental study and numerical modelling." Doctoral thesis, Universitat Politècnica de Catalunya, 2020. http://hdl.handle.net/10803/669488.

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Fibre reinforced concrete (FRC) is recognized as suitable material for structural applications. The number of national codes that have approved it is an evidence. Structures where FRC is generally used can be subjected to fatigue loads and are expected to resist millions of cycles during their service life. Cyclic loads affect significantly the characteristics of materials and can cause fatigue failures. The most demanded cross-sections being cracked under tensile stresses due to direct loads or imposed deformations. Commonly, publications report fatigue behaviour of concrete under compression and are valid for uncracked sections. Imprecision in fatigue prescriptions are reflected through formulation of models that contemplate a probabilistic approach, or an introduction of high safety coefficients within construction codes. The aim of the present doctoral thesis is to perform a structural design oriented analysis on the behaviour of pre-cracked FRC subjected to flexural fatigue loads. FRC with steel and polypropylene fibre with different volume content were investigated by means of three-point bending tests, considering an initial crack width accepted in the service limit state. The mechanical behaviour of FRC were analysed in terms of applied load level, crack opening displacement (CMOD) and fatigue life. The residual flexural tensile strength was assessed after these tests to estimate the impact of the cycles in the remaining resistant capacity of the specimens. Results suggest that the mechanism of crack propagation is independent of the fibre type and content and the monotonic load-crack opening displacement curve might be used as deformation failure criterion for FRC under flexural fatigue loading. The conducted probabilistic approach allows predicting the fatigue strength of concrete reinforced with steel fibres. The findings postulate the proposal of a model to predict the evolution of the crack-opening and the remaining resistant capacity. An optimisation procedure is proposed to derive the model parameters using a limited number of initial load cycles. This doctoral thesis provides knowledge and data that may aid further research and contribute to the future development of design recommendations.
El hormigón reforzado con fibra (FRC) se reconoce como material adecuado para aplicaciones estructurales. El número de normativas que lo han aprobado es una evidencia. Las estructuras donde generalmente se usa FRC pueden estar sujetas a cargas de fatiga y se espera que resistan millones de ciclos durante su vida útil. Las cargas cíclicas afectan significativamente a las características de los materiales y pueden causar roturas por fatiga. Las secciones transversales más demandadas se fisuran bajo tensión debido a cargas directas o deformaciones impuestas. Comúnmente, las publicaciones informan del comportamiento de fatiga del hormigón bajo compresión y son válidas para secciones no fisuradas. La imprecisión de las recomendaciones se refleja a través de la formulación de modelos que contemplan un enfoque probabilístico o la introducción de altos coeficientes de seguridad dentro de los códigos de construcción. El objetivo de la presente tesis doctoral es realizar un análisis orientado al diseño estructural sobre el comportamiento del FRC pre-fisurado sometido a cargas de fatiga por flexión. Se investigaron FRC con fibras de acero y polipropileno con diferentes contenidos de fibras mediante pruebas de flexotracción a tres puntos, considerando un ancho de fisura inicial aceptado en el estado límite de servicio. El comportamiento mecánico del FRC se analizó en términos de nivel de carga aplicada, desplazamiento de apertura de fisura (CMOD) y vida útil bajo fatiga. La resistencia residual a flexotracción se evaluó después de los ciclos de fatiga para estimar el impacto de los ciclos en la capacidad de resistencia restante de las muestras. Los resultados sugieren que el mecanismo de propagación de fisuras es independiente del tipo y contenido de fibra y la curva monotónica de CMOD podría ser utilizada como criterio de falla de deformación para FRC bajo carga de fatiga por flexotracción. El enfoque probabilístico realizado permite predecir la resistencia a la fatiga del hormigón reforzado con fibras de acero. Los resultados postulan la propuesta de un modelo para predecir la evolución de la apertura de fisura y la capacidad resistente remanente. Se propone un procedimiento de optimización para derivar los parámetros del modelo utilizando un número limitado de ciclos de carga inicial. Esta tesis doctoral proporciona conocimiento y datos que pueden ayudar a futuras investigaciones y contribuir al desarrollo futuro de recomendaciones de diseño.
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50

Coetzee, Gerrit. "The mechanical and volumetric behaviour of sisal fibre reinforced concrete blocks." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80010.

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Thesis (MScEng)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: Natural fibre reinforced concrete (NFRC) is a type of concrete that has become of particular interest in recent years, due to its potential for being used as a sustainable and economically viable building material. Natural fibres are often cheap and widely available in developing nations. Sisal is one such fibre predominantly grown in Brazil and has been identified as having the potential to be commercially cultivated in Southern Africa. The durability of sisal fibres in a cementitious environment tends to be adversely affected due to the high alkalinity of pore water and the presence of calcium hydroxide. This research dealt with the use of sisal fibre reinforced concrete (SFRC) blocks. It focused on the mechanical and volumetric properties of blocks with varying fibre and condensed silica fume content (CSF). Two different SFRC blocks were produced (solid and hollow) using an average fibre length of 10 mm. Two matrix types were used: one using a 70:30 cement:fly-ash ratio and another using a 60:30:10 cement:fly-ash:CSF ratio by weight. Samples of each matrix type were prepared with 0, 0.5 and 1% fibre content by volume. Hollow blocks were tested for compressive strength and capillary water absorption, while solid blocks were tested for compressive strength, flexural strength, capillary water absorption, dimensional stability, drying shrinkage, density, total water absorption and void content. All tests were performed on samples with an age of 28 days. Solid block compressive tests were also performed on samples with an age of 7 days. The hollow blocks had significantly lower average compression strength than the solids, but an increase in fibre content caused a slight increase in strength. For solid blocks, it was found that the addition of natural fibres decreases the strength, although a partial substitution of cement with CSF, in conjunction with fibres, did increase the strength relative to blocks without CSF. The flexure strength was also lowered somewhat by the addition of fibres, but an increase in ductility was noted, although not quantified. The addition of CSF to fibre-containing blocks led to an increase in capillary water absorption, but a decrease in absorption through immersion. This shows that the addition of CSF does significantly alter the pore system of a cementitious matrix reinforced with natural fibres. Also, the dimensional stability increased with the addition of CSF and fibres. The same can be said for drying shrinkage. Even though an increase in fibre and CSF caused samples to shrink more under drying, they were more stable under cycles of wetting and drying. It was concluded that the addition of fibres to a matrix had a detrimental effect on strength, although ductility did increase. The volumetric properties of concrete were also adversely affected by the addition of fibres, although dimensional stability was improved. The partial substitution of cement with CSF did improve many of the mechanical and volumetric properties of samples containing sisal fibre.
AFRIKAANSE OPSOMMING: Natuurlike vesel bewapende beton (NVBB) is ’n tipe beton wat onlangs heelwat belangstelling ontlok het weens die potensiaal om gebruik te word as ‘n volhoubare en ekonomiese haalbare boumateriaal. Natuurlike vesels is dikwels baie goedkoop en wyd beskikbaar in ontwikkelende lande. Sisal is een so ‘n vesel wat verkry word vanaf die blare van ’n garingboom. Die plant word hoofsaaklik in Brasilië verbou en is al uitgewys weens sy potensiaal om op kommersiële skaal in Suidelike Afrika verbou te word. Die duursaamheid van sisal vesels is geneig om nadelig geaffekteer te word in die teenwoordigheid van kalsium hidroksied en ’n hoë-alkali omgewing, soos gevind in die porie-water van beton. Hierdie navorsing handel oor die gebruik van sisal vesel bewapende beton (SVBB) boublokke. Dit fokus op die meganiese- en duursaamheids eienskappe van blokke met verkillende inhoude van vesel en gekondenseerde silika dampe (GSD). Twee verskillende SVBB blokke is geproduseer (solied en hol) deur gebruik te maak van 10 mm vesels. Twee matriks tipes is gebruik: een met ’n 70:30 sement:vliegas verhouding en een met ’n 60:30:10 sement:vliegas:GSD verhouding, volgens gewig. Blokke van elke matriks tipe is geproduseer met 0, 0.5 en 1% vesel inhoud, volgens volume. Hol blokke is getoets vir druksterkte en kapillêre water absorpsie, terwyl soliede blokke getoets is vir druksterkte, buigsterkte, kapillêre water absorpsie, dimensionele stabiliteit, krimp onder uitdroging, digtheid, totale water absorpsie en luginhoud. Alle toetse is gedoen op blokke met ’n ouderdom van 28 dae. Druktoetse is ook gedoen op soliede blokke met ’n ouderdom van 7 dae. Die hol blokke het ’n aansienlike laer gemiddelde druksterkte as die soliede blokke gehad, maar ’n toename in veselinhoud het gelei tot ’n effense verhoging in druksterkte. ’n Toename in veselinhoud van soliede blokke het gelei tot ’n afname in druksterkte, alhoewel ’n gedeeltelike vervanging van sement met GSD gelei het tot ’n hoër druksterkte vir blokke met vesels. Die buigsterkte van soliede blokke het ook afgeneem met ’n verhoging in veselinhoud. ’n Verhoging in duktiliteit is waargeneem met ’n toename in veselinhoud, alhoewel dit nie gekwantifiseer is nie. Die toevoeging van GSD tot blokke bevattende vesels het gelei tot ’n verhoging in kapillêre water absorpsie, maar ’n verlaging in totale water absorpsie. Dit kan daarop wys dat die toevoeging van GSD die poriestelsel van NVBB noemenswaardig verander. Beide die dimensionele stabiliteit en krimp onder uitdroging het toegeneem met die toevoeging van GSD en vesels tot die blokke. Dus, die toevoeging het gelei tot ’n hoër krimpvervorming tydens uitdroging en ’n hoër stabiliteit tydens nat/droog siklusse. Daar is tot die gevolgtrekking gekom dat die toevoeging van sisal vesels tot ’n beton blok oor die algemeen ’n negatiewe effek het op sterkte, alhoewel duktiliteit toeneem. Die volumetriese eienskappe van beton word ook negatief geaffekteer met die toevoeging van sisal vesels, alhoewel dimensionele stabiliteit verbeter. Die gedeeltelike vervanging van sement met GSD lei tot die verbetering van beide meganiese en volumetriese eienskappe van beton blokke wat sisal vesels bevat.
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