Download or read book Alkali Silica Reaction written by and published by . This book was released on 2003 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Minimising the Risk of Alkali Silica Reaction written by Cement and Concrete Association and published by . This book was released on 1983-01-01 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Minimising the Risk of Alkali Silica Reaction written by Bec Hooper and published by . This book was released on 2002 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alkali sicilica Reaction written by and published by . This book was released on 1987 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alkali silica reaction written by Concrete Society (Londres). Working Party and published by . This book was released on 1999 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Minimizing The Risk Of Alkali silica Reaction written by and published by . This book was released on 2001 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alkali silica Reaction in Concrete written by CRC Press and published by . This book was released on 1997 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concrete can deteriorate as a result of an interaction between alkaline pore fluids (prinicipally originating from the Portland cements) and reactive minerals in certain types of aggregates. The mechanism of deterioration is known as alkali-aggregate reaction (AAR); it can occur in a number of forms, the most common being alkali-silica reaction (ASR). This Digest is in four parts. Part 1 gives the background to the detailed and simplified guidance contained in Parts 2 and 4. Part 2 gives detailed guidance for minimising the risk of damaging ASR in new construction. Part 3 gives worked examples. Part 4 gives simplified guidance for new construction using aggregates of normal reactivity.
Download or read book Alkali silica Reaction in Concrete written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alkali silica Reaction written by Concrete Society and published by . This book was released on 1995 with total page 47 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Alkali silica Reaction in Concrete written by and published by . This book was released on 1997 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concrete can deteriorate as a result of an interaction between alkaline pore fluids (prinicipally originating from the Portland cements) and reactive minerals in certain types of aggregates. The mechanism of deterioration is known as alkali-aggregate reaction (AAR); it can occur in a number of forms, the most common being alkali-silica reaction (ASR). This Digest is in four parts. Part 1 gives the background to the detailed and simplified guidance contained in Parts 2 and 4. Part 2 gives detailed guidance for minimising the risk of damaging ASR in new construction. Part 3 gives worked examples. Part 4 gives simplified guidance for new construction using aggregates of normal reactivity. This Digest gives guidance for general concreting applications; guidance for concrete in highly specialised applications is outside its scope. For highway structures, in particular, information is available from the Highways Agency.
Download or read book Alkali Aggregate Reaction in Concrete written by Marc-Andre Berube and published by . This book was released on with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book General Guidelines for Minimising the Potential Risk of Deleterious Expansion in Concrete Structures Due to Alkali silica Reaction written by Ahmad Shayan and published by . This book was released on 1992 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: The reaction between alkali hydroxides (usually derived from cement), present in the pore solution of concrete, and aggregates susceptible to the alkali hydroxide attack is termed alkali-aggregate reaction (AAR). Three types of AAR have been identified: alkali-silica reaction, alkali- silicate reaction and alkali-carbonate reaction. These guidelines are intended to bring the producers and users of concrete materials, and designers and specifiers of concrete structures, up to date with general available knowledge on alkali-aggregate reaction (ASR). Research was carried out by CSIRO between 1989-1991 on Queensland materials to minimise the future risk of this problem. The structures and environments which promote ASR are described, as are Australian testing methods and the steps necessary to minimise the effect of ASR in concrete structures.
Download or read book Alkali silica Reaction in Concrete written by CRC Press and published by . This book was released on 1997 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concrete can deteriorate as a result of an interaction between alkaline pore fluids (prinicipally originating from the Portland cements) and reactive minerals in certain types of aggregates. The mechanism of deterioration is known as alkali-aggregate reaction (AAR); it can occur in a number of forms, the most common being alkali-silica reaction (ASR). This Digest is in four parts. Part 1 gives the background to the detailed and simplified guidance contained in Parts 2 and 4. Part 2 gives detailed guidance for minimising the risk of damaging ASR in new construction. Part 3 gives worked examples. Part 4 gives simplified guidance for new construction using aggregates of normal reactivity. This part of the Digest contains simplified, essential recommendations for minimising the risk of damaing ASR; it applies to concrete in which aggregates of normal reactivity are to be used with cementitious materials, with mix designs commonly used in the UK. The decision to provide simplified guidance was taken in response to comments received at the public comment stage of this 1997 revision of the Digest. This simplified guidance is not a substitute for the full recommendations: if you have any doubt about any aspect of this guidance, you should refer to the full text in Part 2. Because the guidance for aggregate combinations classified as normal reactivity is more onerous than that for low reactivity aggregates, the guidance here can be used for both.
Download or read book Alkali silica Reaction in Concrete written by CRC Press and published by . This book was released on 1997 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concrete can deteriorate as a result of an interaction between alkaline pore fluids (prinicipally originating from the Portland cements) and reactive minerals in certain types of aggregates. The mechanism of deterioration is known as alkali-aggregate reaction (AAR); it can occur in a number of forms, the most common being alkali-silica reaction (ASR). This Digest is in four parts. Part 1 gives the background to the detailed and simplified guidance contained in Parts 2 and 4. Part 2 gives detailed guidance for minimising the risk of damaging ASR in new construction. Part 3 gives worked examples. Part 4 gives simplified guidance for new construction using aggregates of normal reactivity. In the following worked examples, the concrete components, and their characteristics, have been selected to meet specified requirements for strength and durability. References to text and tables are to Part 2 of this Digest. When working through an example, refer to Table 1 and Using Table 1 in Part 2.
Download or read book The Alkali Silica Reaction in Concrete written by R N Swamy and published by CRC Press. This book was released on 1991-09-01 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book reviews the fundamental causes and spectrum effects of ASR. It considers he advances that have been made in our understanding of this problem throughout the world.
Download or read book The Effects of Fly Ash and Silica Fume on Alkali silica Reaction in Concrete written by Medhat H. Shehata and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of silica fume and fly ash on reducing the risk of concrete damage due to alkali-silica reaction are presented in this thesis. One silica fume and twenty fly ashes of a wide range of chemical composition were investigated. The effect of the selected materials on expansion when used with high-alkali Portland cement and a siliceous limestone reactive aggregate (Spratt) was evaluated using the concrete prism and the accelerated mortar bar tests. Portland cement pastes and lime/pozzolan blends were prepared using similar combinations of materials used in the expansion tests. These samples were used to study the effects of fly ash and silica fume on the pore solution alkalinity and composition of hydration products. The study showed that the efficiency of fly ash in limiting the risk of deleterious expansion is linked to its efficiency in lowering the pore solution alkalinity. High-calcium and high-alkali fly ashes are generally less effective in this respect compared to low-calcium ash. Silica fume was found to be effective in reducing the pore solution alkalinity at early ages; however, the alkalinity was found to increase at ages later than 28 days. Combinations of moderate levels of silica fume (5%) and high-calcium fly ash (20-30%) were found to be effective in limiting the expansion even after three years. This was attributable to the high capacity of such combinations to achieve and maintain low pore solution alkalinity. The silica fume reduces the pore solution alkalinity at early ages and the fly ash maintained the low alkalinity at later ages. The study showed that, for low and moderate-alkali fly ash, the 14-day expansion in the accelerated mortar bar test could be used to predict the 2-year expansion of concrete prisms. The results from the lime/pozzolan blends confirmed that the hydration products of pozzolan play the dominant role in reducing the pore solution alkalinity of cementitious systems containing pozzolans. The two-year expansion of concrete prisms containing fly ash could be correlated reliably to the alkalis available from the ash as determined by leaching mature paste samples in leaching solution of alkali ion concentration of 0.25 moles per litre.
Download or read book Alkali Aggregate Reaction in Concrete written by Ian Sims and published by CRC Press. This book was released on 2017-08-01 with total page 1044 pages. Available in PDF, EPUB and Kindle. Book excerpt: Alkali-Aggregate Reaction in Concrete: A World Review is unique in providing authoritative and up to date expert information on the causes and effects of Alkali-Aggregate Reaction (AAR) in concrete structures worldwide. In 1992 a first edition entitled The Alkali-Silica Reaction in Concrete, edited by Professor Narayan Swamy, was published in a first attempt to cover this concrete problem from a global perspective, but the coverage was incomplete. This completely new edition offers a fully updated and more universal coverage of the world situation concerning AAR and includes a wealth of new evidence and research information that has accumulated in the intervening years. Although there are various textbooks offering readers sections that deal with AAR deterioration and damage to concrete, no other single book brings together the views of recognised international experts in the field, and the wealth of scattered research information that is available. It provides a ‘state of the art’ review and deals authoritatively with the mechanisms of AAR, its diagnosis and how to treat concrete affected by AAR. It is illustrated by numerous actual examples from around the world, and comprises specialist contributions provided by senior engineers and scientists from many parts of the world. The book is divided into two distinct but complementary parts. The first five chapters deal with the most recent findings concerning the mechanisms involved in the reaction, methods concerning its diagnosis, testing and evaluation, together with an appraisal of current methods used in its avoidance and in the remediation of affected concrete structures. The second part is divided into eleven chapters covering each region of the world in turn. These chapters have been written by experts with specialist knowledge of AAR in the countries involved and include an authoritative appraisal of the problem and its solution as it affects concrete structures in the region. Such an authoritative compilation of information on AAR has not been attempted previously on this scale and this work is therefore an essential source for practising and research civil engineers, consultant engineers and materials scientists, as well as aggregate and cement producers, designers and concrete suppliers, especially regarding projects outside their own region.
