Download or read book The Moisture Effect on the Diffusion of Chloride Ion in Hydrated Cement Paste written by PRL Helene and published by . This book was released on 2000 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previous research [1] showed high chloride concentrations (2% / cement) on the outside surface of reinforced concrete structures in the mist zone of marine environments. However, the chloride penetration reaches low depths for the concrete class used. Observed data have raised suspicions as to the effect of moisture content on the diffusion of chlorides. A test method was developed to assess the changes in the chloride diffusion coefficient with changes in moisture content in cement paste. It was concluded that the saturation degree (SD) (percentage of moisture content in the cement paste in relation to maximum water absorption of the cement paste) has a large influence in the chloride diffusion properties of the hardened cement paste, and this factor must be taken into consideration when predicting the service life of a reinforced concrete structure.
Download or read book Marine Corrosion in Tropical Environments written by S. W. Dean and published by ASTM International. This book was released on 2000 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contains papers presented at a November 2000 symposium, examining laboratory evaluation methods, test methods, and model prediction in research on atmospheric corrosion, corrosion of rebar in concrete, marine corrosion, and other related corrosion phenomena. Topics include degradation of fiber reinf
Download or read book Chloride Ion Diffusion in Low Water to solid Cement Pastes written by and published by . This book was released on 1991 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diffusion coefficients of 0.3 water to solids ratio (w/s) hydrated portland cement paste specimens were measured using a conventional diffusion cell. Specimens were made from both ASTM Type I and Type II portland cements and blends containing mineral admixtures (fly ash, granulated blastfurnace slag, or silica fume). The average diffusion coefficient for the portland cement paste specimens was 14x10-13 m2/s. The diffusion coefficients for the specimens containing mineral admixtures were much more variable than those for the portland cement paste specimens. A probable cause of the variability in the test results was the presence of cracks observed in the test specimens. The effects of the depth of concrete cover over reinforcing steel and of the chloride ion diffusion coefficient on the service life of reinforced concrete exposed to chloride ions were predicted based on a diffusion model. Based on the model, the effect of the cover was shown to be proportional to the square of the cover depth. A 10-fold decrease in the diffusion coefficient of concrete was predicted to result in a 10-fold increase in the predicted service life. Based on the results of the present study, it is recommended that a new chloride diffusivity test should be developed which is applicable to concrete. A candidate test method is proposed.
Download or read book The Diffusion of Chloride Ion in Cement Paste microform written by Kevin MacDonald and published by National Library of Canada = Bibliothèque nationale du Canada. This book was released on 1992 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quality of Concrete Structures and Recent Advances in Concrete Materials and Testing written by Paulo Roberto Lago Helene and published by . This book was released on 2005 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Corrosion of Steel in Concrete written by Luca Bertolini and published by John Wiley & Sons. This book was released on 2013-02-26 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: Steel-reinforced concrete is used ubiquitously as a building material due to its unique combination of the high compressive strength of concrete and the high tensile strength of steel. Therefore, reinforced concrete is an ideal composite material that is used for a wide range of applications in structural engineering such as buildings, bridges, tunnels, harbor quays, foundations, tanks and pipes. To ensure durability of these structures, however, measures must be taken to prevent, diagnose and, if necessary, repair damage to the material especially due to corrosion of the steel reinforcement. The book examines the different aspects of corrosion of steel in concrete, starting from basic and essential mechanisms of the phenomenon, moving up to practical consequences for designers, contractors and owners both for new and existing reinforced and prestressed concrete structures. It covers general aspects of corrosion and protection of reinforcement, forms of attack in the presence of carbonation and chlorides, problems of hydrogen embrittlement as well as techniques of diagnosis, monitoring and repair. This second edition updates the contents with recent findings on the different topics considered and bibliographic references, with particular attention to recent European standards. This book is a self-contained treatment for civil and construction engineers, material scientists, advanced students and architects concerned with the design and maintenance of reinforced concrete structures. Readers will benefit from the knowledge, tools, and methods needed to understand corrosion in reinforced concrete and how to prevent it or keep it within acceptable limits.
Download or read book Individual and Combined Effects of Chloride Sulfate and Magnesium Ions on Hydrated Portland cement Paste written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Ground water with a high concentration of magnesium ion is known to cause deterioration to portland cement concretes. A proposed mechanism for this deterioration process published previously involves an approximate 1:1 replacement of Ca ions by Mg ions in the crystalline phases of hydrated cement. The current study was undertaken to determine which ions, among magnesium, chloride, and sulfate, cause deterioration; whether their deleterious action is individual or interdependent; and to relate this mechanism of deterioration to the outlook for a 100-yr service life of concretes used in mass placements at the Waste Isolation Pilot Plant. Loss of Ca ion by cement pastes was found to be strongly related to the concentration of Mg ion in simulated ground-water solutions in which the paste samples were aged. This was true of both salt- containing and conventional cement pastes. No other ion in the solutions exerted a strong effect on Ca loss. Ca ion left first from calcium hydroxide in the pastes, depleting all calcium hydroxide by 60 days. Some calcium silicate hydrate remained even after 90 days in the solutions with the highest concentration of Mg ion, while the paste samples deteriorated noticeably. The results indicated a mechanism that involves dissolution of Ca phases and transport of Ca ions to the surface of the sample, followed by formation of Mg-bearing phases at this reaction surface rather than directly by substitution within the microstructure of hydrated cement. Given that calcium hydroxide and calcium silicate hydrate are the principal strength-giving phases of hydrated cement, this mechanism indicates the likelihood of significant loss of integrity of a concrete exposed to Mg-bearing ground water at the WIPP. The rate of deterioration ultimately will depend on Mg-ion concentration, the microstructure materials of the concrete exposed to that groundwater, and the availability of brine.
Download or read book Chloride Induced Steel Corrosion in Concrete Under Service Loads written by Hailong Ye and published by Springer Nature. This book was released on 2020-03-27 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarizes the latest advances in understanding chloride ingress and steel corrosion in concrete under service loads. Unlike the existing literature, it focuses specifically on the effect of service loads on chloride-induced durability issues in reinforced concrete structures. It discusses how service loads affect the moisture and chloride penetration rate, corrosion kinetics and rust distribution, as well as the structural performance of concrete components (e.g. beams and columns) in a systematic and hierarchical way. Given its scope, the book is chiefly intended for researchers and industry practitioners in structural engineering, particularly those whose work involves the durability design of concrete structures.
Download or read book Structural Concrete Textbook Vol 1 first edition written by fib Fédération internationale du béton and published by fib Fédération internationale du béton. This book was released on 1999-01-01 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: The development of reinforced and prestressed concrete during the last 50 years was highly promoted by the ”Comité Euro-international du Béton (CEB)“ and the ”Fédération Internationale de la Précontrainte (FIP)“. In 1998 these two associations merged, forming the ”Fédération Internationale du Béton (fib)“. The results of CEB and FIP had been distributed in different ways, such as 'CEB Bulletins d'Information', FIP–Reports, FIP–Notes and CEB–News. These Bulletins or reports comprised various kinds of information, such as State-of-the-Art-Reports, Research Reports, Application Manuals, Guides to Good Practice and the CEB/FIP Model Codes 1978 and 1990. These Model Codes provided design principles and application rules to the structural engineering profession and have been predominantly used for code drafting by many national and international standardizing bodies. The Textbook on Structural Concrete is now intended to provide background information and justification especially for the CEB/FIP Model Code 90 and in some fields of recently extended knowledge. It is addressed to advanced students: this means that basic information on structural analysis and behaviour of structural concrete is a required prerequisite. Practising structural engineers may utilize it for gaining background information on the CEB/FIP Model Code 90 (and national or regional codes as for ex. EUROCODE 2, based on MC 90). The Textbook is also conceived to assist teachers at technical universities or engineering schools to achieve better understanding of the recent theories on structural concrete. Having these targets in mind the General Assembly of CEB decided already in 1995 to set-up a Special Activity Group ”Dissemination of Knowledge“ to realise that work. The authors invited to draft the different chapters had been mostly involved already in drafting the Model Code 90. In this way consistent information could be provided, both for the code and the textbook. Each chapter has been thoroughly discussed and commented within the Special Activity Group 2. This textbook was first presented to fib members during the Technical Activity Workshop in October 1999 in Prague, held in connection with the first fib symposium. The authors are looking forward to receiving comments from various corners.
Download or read book Excellence in Concrete Construction through Innovation written by Mukesh C Limbachiya and published by CRC Press. This book was released on 2008-09-03 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt: The concrete industry has embraced innovation and ensured high levels of long-term performance and sustainability through creative applications in design and construction. As a construction material, the versatility of concrete and its intrinsic benefits mean it is still well placed to meet challenges of the construction industry. Indeed, concrete
Download or read book Research on the Manufacture and Use of Cements written by Geoffrey Frohnsdorff and published by . This book was released on 1986 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Indian Concrete Journal written by and published by . This book was released on 1976 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ceramic Abstracts written by and published by . This book was released on 1994 with total page 972 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Significance of Tests and Properties of Concrete and Concrete making Materials written by Joseph F. Lamond and published by ASTM International. This book was released on 2006 with total page 661 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cementitious Materials written by Herbert Pöllmann and published by Walter de Gruyter GmbH & Co KG. This book was released on 2017-12-18 with total page 518 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aside from water the materials which are used by mankind in highest quantities arecementitious materials and concrete. This book shows how the quality of the technical product depends on mineral phases and their reactions during the hydration and strengthening process. Additives and admixtures infl uence the course of hydration and the properties. Options of reducing the CO2-production in cementitious materials are presented and numerous examples of unhydrous and hydrous phases and their formation conditions are discussed. This editorial work consists of four parts including cement composition and hydration, Special cement and binder mineral phases, Cementitious and binder materials, and Measurement and properties. Every part contains different contributions and covers a broad range within the area. Contents Part I: Cement composition and hydration Diffraction and crystallography applied to anhydrous cements Diffraction and crystallography applied to hydrating cements Synthesis of highly reactive pure cement phases Thermodynamic modelling of cement hydration: Portland cements – blended cements – calcium sulfoaluminate cements Part II: Special cement and binder mineral phases Role of hydrotalcite-type layered double hydroxides in delayed pozzolanic reactions and their bearing on mortar dating Setting control of CAC by substituted acetic acids and crystal structures of their calcium salts Crystallography and crystal chemistry of AFm phases related to cement chemistry Part III: Cementitious and binder materials Chemistry, design and application of hybrid alkali activated binders Binding materials based on calcium sulphates Magnesia building material (Sorel cement) – from basics to application New CO2-reduced cementitious systems Composition and properties of ternary binders Part IV: Measurement and properties Characterization of microstructural properties of Portland cements by analytical scanning electron microscopy Correlating XRD data with technological properties No cement production without refractories
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2692 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Pore Structure of Cement Based Materials written by Kalliopi K. Aligizaki and published by CRC Press. This book was released on 2005-09-22 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pore Structure of Cement-Based Materials provides a thorough treatment of the experimental techniques used to characterize the pore structure of materials. The text presents the principles and practical applications of the techniques used, organized in an easy-to-follow and uncomplicated manner, providing the theoretical background, the way to analyze experimental data, and the factors affecting the results. The book is the single comprehensive source of the techniques most commonly used for pore structure analysis, covering simple techniques like mercury intrusion porosimetry and water absorption, to the more sophisticated small-angle scattering and nuclear magnetic resonance. The book is an essential reference text for researchers, users, and students in materials science, applied physics, and civil engineering, who seek a deep understanding of the principles and limitations of the techniques used for pore structure analysis of cement-based materials.
