Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity...
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Transcript of Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity...
![Page 1: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/1.jpg)
Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC
Using Ultrasonic Pulse Velocityby
X. Wang, P. Taylor, K. Wang, M. Lim
![Page 2: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/2.jpg)
Objectives• Assess ultrasonic pulse velocity applications to
observe concrete stiffening process• Correlate features of ultrasonic compression
wave (P-wave) development to set time and formwork pressure decay
• Provide an insight on surfacing, jointing, and formwork removal of concrete
![Page 3: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/3.jpg)
• Hydration relatedStiffening Process
![Page 4: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/4.jpg)
Stiffening Process• What does it affect?
– Workability:• Hydration• Thixotropy• Loss effectiveness of admixtures
– Formwork pressure• Filling rate
– Jointing• Saw cutting window
![Page 5: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/5.jpg)
Materials• Aggregates
Aggregates in the Research TypeNominal
Maximum Agg. Size, in.
Absorption, % Fineness Modulus
Specific Gravity
Coarse Aggregate
CC-a Limestone 1 0.63 - 2.68CC-b Limestone ¾ 0.77 - 2.67SCC-a Limestone ¾ 1.3 - 2.66SCC-b Limestone ½ 1.3 - 2.66SCC-c Limestone 3/8 1.3 - 2.66
Fine Aggregate
CC-a & CC-b River sand - 1.74 2.84 2.65
CC-b LWA Expanded shale - 16@72hrs 3.55 0.93SCC River sand - 0.5 2.62 2.62
![Page 6: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/6.jpg)
Mixture Proportions• CC
– CC-a: Seven mixtures with two slag types (grade 100 and 120) at 20%, 35%, and 50% replacement level of cement by weight
– CC-b: Eight mixtures with a Class F fly ash at 20% replacement level, which also contain lightweight fine aggregate, integral waterproofer (IWP), shrinkage reducing admixture (SRA), water reducer (WR), and air entraining admixture (AEA).
![Page 7: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/7.jpg)
Mixture Proportions
![Page 8: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/8.jpg)
Mixture Proportions• SCC: based on ACI and ICAR proportioning
methods– Three control mixes (CC): one for each size– 12 mixes designed for cast-in-place bridge
construction applications, made with different aggregate sizes (¾”, ½”, and 3/8”) and different cementitious materials including ground limestone
![Page 9: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/9.jpg)
Mix ProportionsC I,II SCM LD CA FA Water HRWR VMA AEA
Ib/cy Ib/cy Ib/cy Ib/cy Ib/cy Ib/cy oz/cwt oz/cwt oz/cwt T50 (s) Tf inal (s) D (in.) VSI ∆D (in.) ∆H (in.)
CC Control 1 3/4" Limestone 497 166 0 1674 1177 285 0.0 0 0.6 N/A N/A N/A N/A N/A N/A
CC Control 2 1/2" Limestone 591 197 0 1485 1173 315 0.0 0 0.8 N/A N/A N/A N/A N/A N/A
CC Control 3 3/8" Limestone 572 191 0 1350 1356 305 0.0 0 1.5 N/A N/A N/A N/A N/A N/A
SCC-a-C 3/4" Limestone 568 189 0 1518 1242 280 8.0 0 0.8 <2 6.8 27.75 0 0.63 0.56
SCC-a-F 3/4" Limestone 568 189 0 1518 1242 280 8.0 2 0.8 <2 7.8 28.75 1 1.00 0.44
SCC-a-S 3/4" Limestone 539 231 0 1530 1252 280 8.0 2 0.8 2 6.2 29.13 0.5 0.13 0.38
SCC-a-FLD 3/4" Limestone 488 150 106 1518 1242 280 12.0 0 1.5 1.3 7 27.50 0.5 1.75 0.44
SCC-c-C 3/8" Limestone 587 196 0 1334 1334 305 11.0 0 1.3 <2 6.8 23.63 0 1.00 0.25
SCC-c-F 3/8" Limestone 587 196 0 1334 1334 305 10.5 3 1.5 <2 7.6 27.50 0 0.75 0.31
SCC-c-S 3/8" Limestone 558 239 0 1345 1345 305 12.0 0 1.5 2.7 9.5 27.00 0 0.50 0.25
SCC-c-FLD 3/8" Limestone 504 155 116 1334 1334 305 11.0 0 1.5 1.7 8.9 27.25 0 0.75 0.50
SCC-b-C 1/2" Limestone 535 178 0 1462 1297 295 8.0 0 1.0 <2 6.8 23.63 0 0.88 0.31
SCC-b-F 1/2" Limestone 535 178 0 1462 1297 295 6.0 2 1.5 <2 7.1 24.25 0 1.00 0.25
SCC-b-S 1/2" Limestone 525 217 0 1474 1307 295 8.0 0 1.5 <2 6.8 23.50 0 1.00 0.69
SCC-b-FLD 1/2" Limestone 460 141 106 1462 1297 295 6.0 0 1.5 <2 8.3 24.75 0 0.25 0.25
C: Class C fly ash a: 3/4" NMSA FLD: Class F fly ash and limestone dust VSI: visual stability indexF: Class F fly ash b: 1/2" NMSA VMA: vicosity modified admixture AEA: Air entraining admixtureS: slag cement c: 3/8" NMSA HRWR: High range water reducer
Mixture Identification Fresh SCC PropertiesMixture Design
ID
NM
AS Slump Flow J-Ring
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Test Methods• ASTM C403 – penetration resistance • Formwork Pressure-ISU sacrificial formwork
– Flush diaphragm pressure sensor– Loading rate of 6 in/min (9 m/h)– Constant room temperature (72˚F)– Applied pressure up to 30 psi to simulate
30 feet concrete
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Test Methods• Ultrasonic P-wave velocity measurement
– Testing on 4 by 8 in. cylinder up to 1000 mins– Transducer central frequency: 54 kHz– Constant room temperature (72˚F)– Wave path length: 0.65 feet (7.8 inches)
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Ultrasonic Wave Propagation• Ultrasonic Pulse Velocity:
– A stress wave propagation method that involves measurement of the travel time of compression wave pulse over a known path length
• Biot’s theory– The propagation of elastic waves in a porous elastic
solid saturated with a compressive viscous fluid• Longitudinal (compression) waves: related to dynamic
modulus of elasticity, Poisson’s ratio, and density• Transverse (shear) waves• Surface (Rayleigh) waves
![Page 13: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/13.jpg)
P-Wave (Vp) Transmission• Ultrasonic pulse velocity (UPV) device
– Commercial device: Proceq Pundit Lab plus– Vp = L/tp (length of the straight-wave-path through
the specimen/travel time of the ultrasonic pulse)
![Page 14: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/14.jpg)
P-Wave (Vp) Transmission• Ultrasonic pulse velocity (UPV) device
– Commercial device: Proceq Pundit Lab plus– Vp = L/tp (length of the straight-wave-path through
the specimen/travel time of the ultrasonic pulse)
![Page 15: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/15.jpg)
• mixes
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DiscussionInitial Set Time
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Results Summary
C Ash mixes
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Conclusion• P-wave test can be used to monitor the
stiffening process of various concrete mixtures• Set time and formwork pressure decay of
concrete are clearly related to P-wave development
• Potential to provide an insight on surfacing, jointing, and formwork removal of concrete– Planning to correlate with saw-cutting window of
pavements in a forthcoming study
![Page 19: Monitoring Stiffening Behavior of Conventional Concrete (CC) and SCC Using Ultrasonic Pulse Velocity by X. Wang, P. Taylor, K. Wang, M. Lim.](https://reader036.fdocuments.in/reader036/viewer/2022062519/56649cb85503460f9497f424/html5/thumbnails/19.jpg)