compatibility of ultra high performance concrete as repair material

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value to the lowest one in the following order: slant-shear, Bi-Surface (direct shear), thesplitting tensile and pull-off tests.4.1 Combination of Splitting Tensile Test with Freeze-ThawCyclesThis section presents the results of the freezing and thawing performance and indirecttensile strength of the composite and monolithic samples. ASTM C 666 gives a degree ofdeterioration of the specimens subjected to a repetitive freeze-thaw cycling exposure.Measurements of the transverse frequency and mass were taken throughout the test. Thedecrease of these values indicates the deterioration due to the freeze-thaw cycles in thesamples. It is commonly stated that the ASTM C 666 method is more severe than mostnatural exposures (Kosmatka and Wilson 2011).As the stress distribution of the splitting tensile test shows in Figure 3.2, there is auniform tensile stress distribution along the interface plane except for a small area at thecorner that is subjected to compressive stress. Momayez et al. (2005) demonstrated thatthe results of the splitting test are equal or slightly greater than that obtained with thepull-off test.4.1.1 Freeze-thaw cyclesThe repetitive effect of successive freeze thaw cycles can produce the deterioration of theconcrete due to the disruption of paste and aggregate. The freezing of the water causes ahydraulic pressure in the capillaries and pores of the cement paste and aggregate thatmight exceed the tensile strength of the surrounding paste or aggregate resulting in thedilatation and rupture of the cavity (Kosmatka and Wilson 2011).This test focused on the fundamental transverse frequency and mass measurements of thesamples. The decrease of a RDM is a sign of microcrack formation and the reduction inmass measurements shows the disintegration of material (Misson 2008).70
Figure 4.1 shows the mass variation of those composite samples subjected to 300 freezethawcycles. The slight increase between the two first measurements is due to the fact thatthe initial measure was taken in dry conditions while the specimens were saturated in thefollowing measurements. The slight variation between different samples is due to thedifferent thickness of the new and substrate layers. It can be stated that no spallingoccurred in the samples. Figure 4.2 shows the fundamental transverse frequencyevolution of these composite samples. As the weight variation, the initial increment wasdue to the saturation of the samples. It can be appreciated that the fundamental transversefrequency increased slightly with the exposure of the samples to the freeze-thaw cycles.This is explained due to continuation of the hydration as Misson (2008) stated in hisstudy of the UHPC performance under freeze-thaw cycling. The samples underwent anambient air curing regime and it is believed that they had abundant amounts ofunhydrated cement particles that could get hydrated in the presence of water. Graybeal(2006) also noted the gain in strength of UHPC during the freeze thaw process.Weight (grams)1716,51615,51514,5140 50 100 150 200 250 300Freeze-thaw cyclesGr 300 FT (1)Gr 300 FT (2)Gr 300 FT (3)Ch 300 FT (1)Ch 300 FT (2)Ch 300 FT (3)Br 300 FT (1)Br 300 FT (2)Br 300 FT (3)Sm 300 FT (1)Sm 300 FT (2)Sm 300 FT (3)Sb 300 FT (1)Sb 300 FT (2)Sb 300 FT (3)Figure 4.1 Weight of composite samples, cast in wetting conditions, subjected to 300 freeze-thaw cycles71
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COMPATIBILITY OF ULTRA HIGH PERFORM
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Table of ContentsList of Figures ..
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4.3.2 Discussion ..................
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Figure 3.14 CSP index .............
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Table 4.7 Summary of indirect tensi
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List of AbbreviationsACI.AFtASTM.CO
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1 Introduction and MotivationCurren
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2 Background and Literature ReviewT
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spaces and to decrease the amount o
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water/binder=constantChoose steel f
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UHPC formulations and provides a se
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Table 2.3Comparison of UHPC materia
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esults obtained in this project wer
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2.1.3.4 Environmental Impact of UHP
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1997). Emmons and Vaysburd (1996) d
Page 32 and 33: e) ConstructabilityIt is recommenda
Page 34 and 35: Table 2.5, continuedCementitious ma
Page 36 and 37: • Rehabilitation of a bridge pier
Page 38 and 39: UHPC is a cost-effective solution i
Page 40 and 41: apparatus will measure the shear st
Page 42 and 43: substrate while the scarifying meth
Page 44 and 45: such test configuration, this upper
Page 46 and 47: From the equilibrium of forces of F
Page 48 and 49: The first layer, also called penetr
Page 50 and 51: 3 MethodologyThis report aims to st
Page 52 and 53: f sp = 2 ∗ PA ∗ π in psi Equat
Page 54 and 55: that the bond interface, in this lo
Page 56 and 57: Ductal® premix is typically compri
Page 58 and 59: associated test results (temperatur
Page 60 and 61: Figure 3.2 Detail of splitting tens
Page 62 and 63: 3.3.3 Pull-off testPull off test wa
Page 64 and 65: (a) Chipped surface, slightlybrushe
Page 66 and 67: (a) Molds to cast slant shearspecim
Page 68 and 69: Timber moulds were used to cast the
Page 70 and 71: macrotexture depth was measured in
Page 72 and 73: As shown in the above tables, the m
Page 74 and 75: (a) Concrete substrate under water
Page 76 and 77: used, as shown in Figure 3.17. A fa
Page 78 and 79: Equation 2.2 and Equation 2.3 were
Page 80 and 81: (a) Steel disks glued to the UHPC s
Page 84 and 85: Transversal frequency (Hz)255025002
Page 86 and 87: 115113Relative Dynamic Modulus (%)1
Page 88 and 89: Only those specimens with a grooved
Page 90 and 91: Table 4.6, continued.MeanMeanCOV,st
Page 92 and 93: concrete or bond/concrete while for
Page 94 and 95: surface treatment applied. In contr
Page 96 and 97: Table 4.8Summary of slant-shear tes
Page 98 and 99: (a) B(C): Bond due to concrete fail
Page 100 and 101: 3143Bond Capacity, (psi)30002500200
Page 102 and 103: The different failure modes obtaine
Page 104 and 105: failures occurred in the concrete s
Page 106 and 107: property of the concrete has higher
Page 108 and 109: 5.1.1 Combination of Splitting Tens
Page 110 and 111: 5.1.4 Overall performancea. For thi
Page 112 and 113: mismatch and load eccentricity. Tho
Page 114 and 115: 6 ReferenceAbu-Tair, A. I., Rigden,
Page 116 and 117: Climaco, J. C. T. S., and Regan, P.
Page 118 and 119: Graybeal, B., and Tanesi, J. (2007)
Page 120 and 121: Misson, D. (2008). "Influence of Cu
Page 122 and 123: Silfwerbrand, J. (1990). "Improving
Page 124 and 125: 7 Appendix: NSC mix designsTable 7.
Page 126 and 127: Table 7.33rd mix for the splitting
Page 128 and 129: Table 7.51st mix for the splitting
Page 130 and 131: Table 7.73rd mix for the splitting
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Figure 8.2 Concrete retarder inform
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Table 9.1, continued.BrBr w/oBr 300
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Table 9.2, continued.TrialBrushed 6
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10 Appendix: Splitting tensile pris
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Table 10.1, continued.128
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Table 10.2Splitting monolithic NSC
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11 Appendix: Slant-shear specimens
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PortionNumberof 1figures/tables/ill
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Figure 2.5Miguel Angel Carbonell Mu
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Miguel Angel Carbonell Munoz Mon, M
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Miguel - not sure what you need fro
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End Page 1235Type of UsePortionNumb
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Type of UseIntended publisher of ot
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