Alkali-Silica Reaction (ASR) is one of the most severe damage reactions of concrete. There are at least two different mechanisms of ASR: The most common is the rapid disruption of siliceous aggregates at the surface of the grain, which occurs in flint and opal sandstone, for example: The ...
Alkali silica reaction (ASR) occurs due to chemical reaction between hydroxyl ions in the pore water within the concrete matrix and certain forms of silica. This reaction could lead to strength loss, cracking, volume expansion and potentially failure of the structure. This manuscript reports findings...
The neutralisation process, induced by mixing concrete with both coarse and fine chert aggregates, is so dominant that the "local" alkali threshold causing the reaction is rarely exceeded, and expansions are below the standard limit. In terms of application, knowledge of the alkali threshold may ...
SIS-CEN/TR 16349:2012避免碱 硅反应(ASR)对混凝土造成损害的规范框架 Framework for a specification on the avoidance of a damaging Alkali-Silica Reaction (ASR) in concrete首页 标准 SIS-CEN/TR 16349:2012 发布历史 SIS-CEN/TR 16349:2012 预览[下载] 发布历史SIS-CEN/TR 16349:2012...
Expansive alkali silica gel forms due to the alkali reaction with reactive aggregates. Cracks and damage to the part of the concrete structure are the results of the formation of this expansive gel. There are several ways to minimize this reaction, out of which Lithium Nitrate compound is belie...
In regions of the world with reactive aggregate, Alkali-Silica Reaction (ASR) is a relentless infrastructure assassin. If the seeds of ASR—reactive aggregate and Portland cement spawned calcium hydroxide—are present in cured concrete, that concrete structure will not survive to the end of its en...
Alkali-silica reaction (ASR) in concrete can induce degradation in its mechanical properties, leading to compromised serviceability and even loss in load capacity of concrete structures. Compared to other properties, ASR often affects the modulus of elasticity more significantly. Several empirical models...
Field Test to identify Alkali Silica Reaction (ASR) in concrete. Two reagents are applied to the broken surface of a concrete core and the excess rinsed off. On contaminated concrete, the resultant stains reveal the presence of ASR. The stains also reveal the extent of the ASR in the concre...
Alkali-silica-reaction (ASR) exposure sites allow studying the behavior of concrete with reactive aggregates in natural exposure on the long term. As such, the exposed specimens can show both the kinetics and magnitude of concrete expansion and the effectiveness of ASR-suppressing measures. More...
This paper examines the dimensional change of concrete prisms that were fabricated using concrete made with either sodium silicate or sodium carbonate ABFSC binder incorporating either an innocuous control aggregate, an aggregate that is known to be reactive by way of ASR or ACR in ordinary Portland...