Download or read book Effects of Air Void Parameters and Water cementitious Ratio on the Durability Performance of Portland Cement Concrete written by Richard A. Walls and published by . This book was released on 2000 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Freeze thaw Durability and Air Void Parameters of Some Concretes written by Peter B. Makowichuk and published by . This book was released on 1963 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies on the determination of air void parameters by microscopic analysis of polished concrete sections were correlated with freeze-thaw durability tests in order to compare the durability characteristics of concrete made using high early strength cement, normal Portland cement and normal portland cement with calcium chloride added a.s an accelerator. The results indicate that for a curing period of fourteen days the use of high early strength cement and the use of calcium chloride treated cement affects freeze-thaw durability in two ways. First, the increased rate of hydration proves beneficial as it provides the concrete with a higher strength at an earlier age. Second, the addition of calcium chloride and the use of high early strength cement results in an inferior air void system in the concrete which lowers the freeze-thaw durability. The change due to calcium chloride on the amount of hydration and on the air void system varies with the water cement ra.tio. Thus at high water cement ratios, the increases in the amount of hydration by the addition of calcium chloride or by the use of high early strength cement is great enough to offset the detrimental change in the air void system, and there is no significant change in durability. However at the lower water cement ratios the increase in amount of hydration is less and the detrimental effects on the air void system are more pronounced so that the durability is lowered considerably.

Download or read book Concrete Bridge Deck Performance written by H. G. Russell and published by Transportation Research Board. This book was released on 2004 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: At head of title: National Cooperative Highway Research Program.

Download or read book Durability of Concrete in Cold Climates written by M. Pigeon and published by CRC Press. This book was released on 2014-04-21 with total page 259 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a comprehensive and authoritative review of durability of the frost resistance of concrete. It will enable both concrete materials specialists and practising engineers to better understand the deterioration processes which take place during freezing and thawing, and the effects of de-icing salts on concrete. It shows how test pro

Download or read book Field Study of Air Content Stability in the Slipform Paving Process written by and published by . This book was released on 2012 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study evaluated the impacts of construction on the air content and air-void system structure of Portland cement concrete pavements. The primary intent was to quantify the air content of fresh concrete before and after it has gone through the slipform paver. The air-void system parameters of hardened concrete were then assessed using cast and extracted core specimens. The results of the air content testing on fresh concrete and the concrete cylinder specimens cast in the field suggested that there is some loss of air as the concrete passes through the paver. Laboratory testing performed on cores extracted from the pavement did not provide any conclusive evidence that entrained air is lost during the slipform paving process. In fact, many of the extracted cores had measured air content values that were much higher than the specification requirement. If excessive, this could result in increased permeability and low-strength related issues. Although a rigorous statistical analysis was not performed, the results suggest that the air content testing on fresh concrete is not capturing the true air content of the concrete placed with a slipform paver. The fresh concrete air content is generally lower than the air content measured in the cores.

Download or read book Parametric Study of the Effects of Water to Cementitious Materials Ratio and Cementitious Materials Content on the Durability Properties of High Performance Concrete written by and published by . This book was released on 2007 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study takes a detailed look at the factors that affect the durability of concrete and how they can be applied to the development of a useful performance specification and help to extend the life of bridge decks and other concrete structures exposed to the elements of nature. A series of fifteen mixes (with varying cement contents and water/cement ratios) were performed in order to determine exactly which of these factors have a significant effect on the durability of a concrete mix. Controlling the water/cement ratio is necessary in order to control strength and permeability. Cement content was found to have little bearing on strength while the amount of cement affected the shrinkage significantly. Shrinkage is also dramatically affected by the amount of water in the mix. The results of the mixes were then used to develop a new specification for a bridge deck mix that will potentially improve the lifespan of bridge decks. Prescriptive versus performance specifications were also explored with the benefits and deficiencies of each form of specification looked at in detail.

Download or read book The Effect of Surface active Agent and Water cement Ratio on the Diffusion of Air in the Air Void System of Portland Cement Concrete written by Charles P. O'Neill and published by . This book was released on 1965 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Frost Resistance of Portland Cement Concrete Prepared with Chemical and Mineral Admixtures at Marginal Air Content written by Shamshad Ahmad Khan and published by . This book was released on 1992 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Concrete Abstracts written by and published by . This book was released on 1986 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modern Concrete Materials written by Ravindra K. Dhir and published by Thomas Telford. This book was released on 1999 with total page 720 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concrete will be the key material for Mankind to create the built environment of the next millennium. The requirements of this infrastructure will be bothde manding, in terms of technical performance and economy, and yet be greatly varied, from architectural masterpieces to the simplest of utilities.Modern concrete materials: Binders, Additions and Admixtures forms the proceedings of the three day International Conference held during the Congress, Creating with Concrete, 6-10 September 1999, organised by the Concrete Technology Unit, University of Dundee.

Download or read book Effects of Duration of Moist Curing on Concrete Made with Blended Cements Or Pozzolans written by William O. Tynes and published by . This book was released on 1969 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book INFLUENCE OF AIR VOID SYSTEM ON FREEZE THAW DURABILITY OF CONCRETE written by ZAFAR AHMED MALIK and published by . This book was released on 1991 with total page 530 pages. Available in PDF, EPUB and Kindle. Book excerpt: Two-way analysis of variance showed that type of air entraining agent, quality of aggregate, and content of condensed silica fume have a major effect on freeze-thaw durability of concrete.

Download or read book Examination of Microscopic Air void Parameters in Portland Cement Concrete written by John D. Squires and published by . This book was released on 1988 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance and durability of cementitious materials written by Harald Justnes and published by . This book was released on 1997 with total page 646 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Various Air entraining Agents on the Durability of Concrete written by and published by . This book was released on 1960 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Cement Performance in Concrete written by Bryant Mather and published by . This book was released on 1967 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Wet Curing Duration on Durability Parameters of Hydraulic Cement Concretes written by Daniel Stephen Lane and published by . This book was released on 2010 with total page 41 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hydraulic cement concrete slabs were cast and stored outdoors in Charlottesville, Virginia, to study the impact of wet curing duration on durability parameters. Concrete mixtures were produced using portland cement, portland cement with slag cement, and portland cement with Class F fly ash concretes with water-cementitious materials ratios (w/cm) of 0.45 and 0.35. These concretes were subjected to immediate liquid membrane-forming curing or 1, 3, 7, or 14 days wet curing. Two slabs were cast for each of the wet curing durations. Following the curing period, one slab was allowed to dry naturally, and liquid membrane-forming curing compound was applied to the other. Three additional concretes containing saturated lightweight fine aggregate were produced to study the potential impact of internal curing on the durability parameters. These concretes contained portland cement with fly ash, silica fume, and both, at 0.35 w/cm. Three slabs were cast from each mixture and subjected to liquid membrane-forming curing, 1 or 3 days wet curing. The slabs were instrumented with humidity probes at two depths below the surface. Specimens were removed from two depths and tested for tensile strength, electrical conductivity, and sorptivity at 3 and 12 months of age. The success rate of the humidity measurements within the slabs was low because of water condensation. However, water condensation qualitatively indicates that the slabs did not dry out to an extent that would adversely impact concrete property development. Neither the strength, electrical conductivity, nor sorptivity results were impacted appreciably by the duration of moist curing. At most, 1 to 3 days wet curing was sufficient. Reducing w/cm had a positive impact on reducing permeability parameters, and previous work by others has shown the duration of curing needed to achieve discontinuity in the capillary pore system decreases with decreasing w/cm. No added benefit was observed by application of liquid membrane-forming curing following the wet curing. The prevailing weather conditions in the months during and following placement were humid, which would obviate any benefit from post wet-curing applications of liquid membrane-forming curing compound to slow drying. Prevailing weather conditions and the w/cm of the concrete mixture are important factors in determining adequate curing procedures and duration and should be considered by the project management team at the time of construction to establish appropriate procedures. A direct cost savings could be realized by removing the requirement for wet curing and using LMFC only in situations where it is likely to benefit the curing process. Alternatively, there may be long-term benefits that could be realized by applying these cost savings to the application of penetrating sealers, particularly for concretes that will be subjected early in their life to aggressive anti-icing and deicing programs..