[PDF] Stress Effects On The Freeze Thaw Durability Of Concrete eBook

Author : Joseph P. Callahan
Publisher : Highway Research Board
Page : 70 pages
File Size : 10,66 MB
Release : 1970
Category : Bridges, Concrete
ISBN : 9780309018890

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This report is recommended to bridge design engineers, construction engineers, concrete researchers and others concerned with concrete bridge deck deterioration. It contains the findings of research conducted to determine if stresses resulting from the action of traffic, differential settlement, warping of slabs and volume changes in the concrete will initiate or accelerate deterioration during freezing and thawing of concrete exposed to a deicing solution.

Author : J. Marchand
Publisher : CRC Press
Page : 323 pages
File Size : 42,46 MB
Release : 2004-03-01
Category : Architecture
ISBN : 0203627091

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Concrete durability in climates where freezing and thawing occurs is a continuing problem. It is particularly acute for highway and bridge structures, where de-icing salts are used to combat the effects of frost, snow and ice. These salts can cause damage to concrete and accelerate corrosion of reinforcements. This book presents the latest international research on this area, with contributions from North America and Europe which were presented at an international RILEM workshop.

Author : Ahmad A. Ghadban
Publisher :
Page : pages
File Size : 26,21 MB
Release : 2016
Category :
ISBN :

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Pre-stressed concrete is used for manufacturing railroad ties. Air entrainment is used in concrete railroad ties to provide durability in freeze-thaw conditions commonly present in track. Vibration practices in pre-stressed concrete railroad tie plants could contribute to excessive air loss during manufacture and thus poor freeze-thaw resistance. Rheological properties of fresh concrete significantly influence the determination of how much air is lost during vibration. This research attempted to increase understanding of the effect of vibration on air bubble distribution and freeze-thaw resistance of concrete given certain compositions and rheological properties of concrete. The objective was achieved by examining the effect of different admixtures combinations, vibration parameters, and rheological properties on the air void system and freeze-thaw resistance of concrete. This research also proposed a method to measure rheological properties of concrete when vibrated and for concrete mixtures too stiff to measure using conventional rheology measurements. Results showed that delaying the initiation of vibration can cause significant air loss but does not necessarily decrease freeze-thaw performance of concrete. Results also showed that a majority of air loss occurs in the first 30 seconds of vibration. The types of admixtures used in the concrete mixture can significantly affect the air system and freeze-thaw durability of concrete; this effect was shown to be more pronounced in mixtures with low yield stress and plastic viscosity. While the peak vibration acceleration had a mild effect, the frequency and peak velocity of vibration did not seem to have a noticeable effect on the air system and freeze-thaw performance of concrete. Results also showed that rheological properties of stiff mixtures can be estimated by running the rheology test during vibration.

Author : Mohammed T. Albahttiti
Publisher :
Page : pages
File Size : 27,40 MB
Release : 2015
Category :
ISBN :

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Air voids are purposefully entrained in concrete to provide freeze-thaw durability of prestressed concrete railroad ties. Durability assurance requires consistent provision of an air void system comprised of small, well-distributed bubbles in sufficient quantity for durability and a quality control method for testing tie freeze-thaw durability. Manufacturing processes at three concrete manufacturing plants were investigated in order to determine the effects of process variability on resulting concrete air void system variability. Variation in the concrete air void system and other rheological properties occurred as results of the manufacturing process and vibration. Freezing and thawing durability testing of prestressed concrete ties is currently performed by applying ASTM C666 on 3 x 4 x 11 to 16 in. specimens cut from the shoulders of concrete ties. However, excising these specimens from prestressed concrete could lead to stress changes in the sample and cracking, potentially causing false interpretations of results. Therefore, testing was undertaken to understand the effects of prestressing and sample extraction on freeze-thaw durability measured by ASTM C666. In order to assess the effects of sampling and testing procedures on freeze-thaw quality control testing results of prestressed concrete railroad ties, full ties, half ties, and 3 x 4 x 11 in. excised samples were tested. Freeze-thaw testing included determination of the optimal method to measure freeze-thaw deterioration in large sections, the effects of saw-cutting, and the presence of reinforcement. Results indicated that the Ultrasonic Pulse Velocity accurately represented deterioration in large sections. The presence of reinforcement in excised samples led to faster deterioration compared to cast ASTM C666 samples, while saw-cutting without reinforcement did not significantly affect freeze-thaw durability.

Author : R Auberg
Publisher : CRC Press
Page : 400 pages
File Size : 40,33 MB
Release : 2004-03-01
Category : Architecture
ISBN : 0203627326

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This book forms the proceedings of the international workshop to be held in Essen, Germany. This workshop summarises the conclusion of the technical committee's investigations into the resistance of concrete to freeze-thaw attack, specific in this to resistance with or without de-icing chemicals. It presents the RILEM recommendations on testing the freeze-thaw and de-icing salt resistance of concrete.

Author : M. Alexander
Publisher : CRC PressI Llc
Page : 544 pages
File Size : 18,19 MB
Release : 2006-01-01
Category : Science
ISBN : 9780415396561

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The First International Conference on Concrete Repair, Rehabilitation and Retrofitting (ICCRRR 2005) was held in Cape Town, South Africa, in November 2005. The conference was a collaborative venture by researchers from the South African Research Programme in Concrete Materials (based at the Universities of Cape Town and The Witwatersrand) and The Construction Materials Section at Leipzig University in Germany. The conference focused on appropriate repairing, maintaining, rehabilitating, and, if necessary, retrofitting existing infrastructure with a view to extending its life and maximising its economic return.

Author : Kefei Li
Publisher : John Wiley & Sons
Page : 296 pages
File Size : 48,95 MB
Release : 2017-05-01
Category : Technology & Engineering
ISBN : 1118910095

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Comprehensive coverage of durability of concrete at both material and structural levels, with design related issues Links two active fields in materials science and structural engineering: the durability processes of concrete materials and design methods of concrete structures Facilitates communication between the two communities, helping to implement life-cycle concepts into future design methods of concrete structures Presents state-of-the-art information on the deterioration mechanism and performance evolution of structural concrete under environmental actions and the design methods for durability of concrete structures Provides efficient support and practical tools for life-cycle oriented structural design which has been widely recognized as a new generation of design philosophy for engineering structures The author has long experience working with the topic and the materials presented have been part of the author's current teaching course of Durability and Assessment of Engineering Structures for graduate students at Tsinghua University The design methods and approaches for durability of concrete structures are developed from newly finished high level research projects and have been employed as recommended provisions in design code including Chinese Code and Eurocode 2