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Alkali-Silica Reaction In Concrete - idc-online

2019-2-4  Alkali-silica reaction (ASR) in concrete is a reaction between certain silicious constituents in the aggregate and the alkali-sodium and potassium hydroxide which are released during the hydration of Portland cement. A gelatinous product is formed which imbibes pore fluid and

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Alkali-Aggregate Reaction - cement

Alkali-silica reaction (ASR) is of more concern because aggregates containing reactive silica materials are more common. In ASR, aggregates containing certain forms of silica will react with alkali hydroxide in concrete to form a gel that swells as it adsorbs water

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Alkali-Silica Reaction In Concrete - Civil Engineering ...

The alkali-silica reaction though not true is described as a concrete cancer. A human cancer, if untreated is terminal, whereas the alkali-silica reaction and the expansion it induces, if untreated, eventually stops. No concreted structure or part of a concrete structure any where in the world has collapsed due to alkali-silica reaction alone.

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Alkali silica and pozzolanic reactions in concrete. Part 1 ...

1987-1-1  This reaction, called pozzolanic reaction, not oniy reduces the expansion of concrete due to alkali silica reaction but improves the quality of concrete in the long term. 141 142 Vol. 17, No. 1 S. Urhan Despite the extensive work on these two reactions in concrete, the conditions favoring the formation of on alkali silicate gel by alkali silica ...

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Evaluation of alkali–silica reaction damage in concrete by ...

2021-7-2  Alkali–Silica Reaction (ASR) occurs between cement alkalis and some aggregate types and causes expansion and damage in concrete. The most common and effective way to rate the severity of ASR damage in structural members is to conduct crack imaging and microstructural analysis on the core samples taken from the structures. However, it is also essential to monitor the damage with non ...

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(PDF) alkali-silica reaction in high strength concrete

The Stiffness Damage Test (SDT) is an interesting tool for assessing damage in concrete affected by alkali-silica reaction (ASR). It has been found that the use of a fixed

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Alkali-silica reaction in concrete: Mechanisms, mitigation ...

Abstract. In the last few decades, the alkali–silica reaction (ASR) has been reported as one of the major concrete concerns regarding durability, leading to high maintenance and reconstruction costs. The occurrence of ASR in numerous concrete infrastructures all over the world points to the need for research regarding measures for its ...

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Modeling of alkali-silica reaction in concrete: a review ...

2012-3-31  This paper presents a comprehensive review of modeling of alkali-silica reaction (ASR) in concrete. Such modeling is essential for investigating the chemical expansion mechanism and the subsequent influence on the mechanical aspects of the material. The concept of ASR and the mechanism of expansion are first outlined, and the state-of-the-art of modeling for ASR, the focus of the paper, is ...

More

Alkali-Silica Reaction In Concrete - Civil Engineering ...

The alkali-silica reaction though not true is described as a concrete cancer. A human cancer, if untreated is terminal, whereas the alkali-silica reaction and the expansion it induces, if untreated, eventually stops. No concreted structure or part of a concrete structure any where in the world has collapsed due to alkali-silica reaction alone.

More

Alkali-silica reaction in concrete - ICE Virtual Library

2015-7-7  Yoon Safe limit on alkali content in alkali-silica reaction Rev. 39th Gen. Meet. Cem. Ass. Jap. Tokyo May 1985 CAJ 1985 240- 243 10 K. E. Putterill , and R. E. Oberholster Investigations of different variables that influence the expansion of concrete caused by alkali-aggregate reaction under natural environmental conditions National Building ...

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Overview of Alkali-Silica Reactivity in Concrete Pavements

2020-12-16  national-concrete-consortium Introduction Alkali-aggregate reaction (AAR) is a poten-tial distress mechanism for portland cement concrete (PCC) that results from a reaction between alkali hydroxides in the PCC pore solution and reactive aggregates. The most common occurrence of AAR is the alkali-silica reaction (ASR) that results from reac-

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(PDF) alkali-silica reaction in high strength concrete

The Stiffness Damage Test (SDT) is an interesting tool for assessing damage in concrete affected by alkali-silica reaction (ASR). It has been found that the use of a fixed loading over the test ...

More

Alkali-silica reaction in concrete containing glass ...

2009-1-20  The use of surplus waste glass in concrete has been avoided on the grounds that it is known to undergo harmful alkali-silica reaction (ASR). As part of a research project to develop draft specifications for glass in concrete, a major ASR testing programme was undertaken to establish appropriate use of glass in concrete which avoided harmful ASR. The British Standard for assessing

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Modeling of alkali-silica reaction in concrete: a review ...

2012-3-31  This paper presents a comprehensive review of modeling of alkali-silica reaction (ASR) in concrete. Such modeling is essential for investigating the chemical expansion mechanism and the subsequent influence on the mechanical aspects of the material. The concept of ASR and the mechanism of expansion are first outlined, and the state-of-the-art of modeling for ASR, the focus of the paper, is ...

More

(PDF) Modeling of alkali-silica reaction in concrete: A review

2021-11-24  The alkali-silica reaction in concrete is a chemical reaction. that occurs between amorphous or poorly crystalline silica. present in reactive aggregate and alkali and hydroxyl ions.

More

Alkali-Aggregate Reaction - cement

Alkali-silica reaction (ASR) is of more concern because aggregates containing reactive silica materials are more common. In ASR, aggregates containing certain forms of silica will react with alkali hydroxide in concrete to form a gel that swells as it adsorbs water

More

Cement Type Influence on Alkali-Silica Reaction in ...

2017-10-25  Alkali-silica reaction is one of the chemical reactions which have a significant influence for durability of concrete. During alkali and silica reaction, silicon located in aggregates of the concrete, reacts with high alkali content. This way in the micropores of concrete is forming hygroscopic gel, which at wet environment, expanding and ...

More

(PDF) Alkali-silica Reaction in Finnish Concrete Structures

progress of alkali-silica reaction in res ent cases in Finni sh concrete structur es. Nordic Concrete Research – P ubl. No. NCR 59 – ISSUE 2 / 2018 – Article 3, pp. 31-44 33

More

Overview of Alkali-Silica Reactivity in Concrete Pavements

2020-12-16  national-concrete-consortium Introduction Alkali-aggregate reaction (AAR) is a poten-tial distress mechanism for portland cement concrete (PCC) that results from a reaction between alkali hydroxides in the PCC pore solution and reactive aggregates. The most common occurrence of AAR is the alkali-silica reaction (ASR) that results from reac-

More

Alkali-silica reaction in concrete: Mechanisms, mitigation ...

The alkali–silica reaction (ASR) is one of the major long-term deterioration mechanisms occurring in concrete structures subjected to high humidity levels, such as bridges and dams. ASR is a ...

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Alkali-silica reaction in concrete - ICE Virtual Library

2015-7-7  Panel discussion: Practical application of research findings Proc. 5th Int. Conf. Alkali-aggregate reaction in concrete, Cape Town, 30 Mar.–3 Apr. 1981 National Building Research Institute Pretoria 1981 PD1-6 6 K. Kishitami , and J. H. Yoon Safe limit on alkali content in alkali-silica reaction Rev. 39th Gen. Meet. Cem. Ass. Jap. Tokyo May ...

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(PDF) alkali-silica reaction in high strength concrete

The Stiffness Damage Test (SDT) is an interesting tool for assessing damage in concrete affected by alkali-silica reaction (ASR). It has been found that the use of a fixed loading over the test ...

More

Alkali-Silica Reaction and High Performance Concrete

Damage due to alkali-silica reaction (ASR) in concrete is a phenomenon that was first recognized in the U. S. since 1940 and has since been observed in many countries. Despite numerous studies published, the mechanism is not yet clearly understood. Nevertheless, the three major factors in concrete have been identified, i.e., the alkalies

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(PDF) Modeling of alkali-silica reaction in concrete: A review

2021-11-24  The alkali-silica reaction in concrete is a chemical reaction. that occurs between amorphous or poorly crystalline silica. present in reactive aggregate and alkali and hydroxyl ions.

More

Alkali-silica reaction in concrete containing glass ...

The use of surplus waste glass in concrete has been avoided on the grounds that it is known to undergo harmful alkali-silica reaction (ASR). As part of a research project to develop draft ...

More

Cement Type Influence on Alkali-Silica Reaction in ...

2017-10-25  Alkali-silica reaction is one of the chemical reactions which have a significant influence for durability of concrete. During alkali and silica reaction, silicon located in aggregates of the concrete, reacts with high alkali content. This way in the micropores of concrete is forming hygroscopic gel, which at wet environment, expanding and ...

More

(PDF) Alkali-silica Reaction in Finnish Concrete Structures

progress of alkali-silica reaction in res ent cases in Finni sh concrete structur es. Nordic Concrete Research – P ubl. No. NCR 59 – ISSUE 2 / 2018 – Article 3, pp. 31-44 33

More

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