70 years of ASR with no end in sight? (Part 1)

Summary: The deleterious ASR in concrete is an extremely complex long-term reaction. The amount and condition of the quartz in the aggregates play the decisive role. The alkali-silica gel is capable of swelling only in a certain range of the CaO content. Thus, all cement admixtures, which bind Ca(OH)2 formed during the C3S and C2S hydration, help to avoid a deterioration of concrete by ASR. If the currently available test methods, in particular the ASR performance test, are used consistently, a deleterious ASR could be avoided. This can be done by adapting the binder or by the strict exclusion of alkali-reactive aggregates. Part 1 summarizes general mechanisms, ASR test methods and their pros and cons, part 2 gives in-depth information on specific research approaches, selected test methods and field cases of ASR-damaged structures.

1 Introduction

In 1940, for the first time Stanton determined that deterioration of concrete in the form of map cracking, pop-outs and gel exudation is the result of a reaction between the alkalis of the cement and the aggregates containing soluble silica [1]. The first documented case of damage in the world was at the Buck hydro-electric plant on the New River in Virginia (USA) where damage was detected in 1922, i.e. only 10 years after its construction [2]. The damages caused by ASR in the USA triggered comprehensive research regarding the causes, the development of testing methods and trials...

Related articles:

Issue 05/2010

70 years of ASR with no end in sight? (Part 2)

4 ASR investigations at the FIB A reliable evaluation of the ASR damaging potential of individual aggregates and project-specific concretes can be given, as matters stand at the moment, due to the...

more
Issue 7/2023 WACKER CHEMIE AG

Concrete: silicone-based additive inhibits alkali-aggregate reactions

Introduction Sand scarcity in the construction industry is a worldwide problem [1, 2, 3, 4, 5]. Owing to the scarcity of suitable sand and aggregates, the industry is increasingly turning to...

more
Issue 9/2020 WACKER CHEMIE AG

Durability enhancement for cementitious materials through waterproofing by organosilicon chemistry

1 Introduction Cementitious materials like concrete are mainly composed of aggregates of various sizes such as sand and rock, which are bonded together by fresh cement paste and become a rigid mass...

more
Issue 12/2017 BAUHAUS-UNIVERSITät Weimar

Repair materials for sulphatically and ­hydraulically bonded masonry

1 Introduction In several parts of Germany, at least until the late 19th century, many buildings made of artificial stone (e.g., bricks) and natural stone (e.g., slate, limestone, sandstone, gypsum...

more
Issue 4/2022 BOOK REVIEW

Characterize structural changes in cementitious building materials by acoustic non-destructive testing methods

The original title of the German dissertation by René Tatarin is “Charakterisieren struktureller Veränderungen in zementgebundenen Baustoffen durch akustische zerstörungsfreie Prüfverfahren”. In...

more