# Evaluation of the Alkali–Silica Reaction Potential of Korean Aggregates: Experimental Insights and Mitigation Strategies for Concrete Durability

## TL;DR

This study evaluates the potential for concrete damage from alkali-silica reactions in Korean aggregates and suggests strategies to improve durability.

## Contribution

The study provides experimental insights into ASR potential in Korean aggregates and recommends mitigation strategies for concrete durability.

## Key findings

- Some Korean aggregates showed expansion levels (0.1–0.2%) classified as potentially deleterious due to ASR.
- High anomalies in soundness, acid production, and weathering indicate additional durability risks beyond ASR.
- The study recommends routine ASR testing and the use of supplementary cementitious materials to ensure long-term durability.

## Abstract

The alkali–silica reaction (ASR) is an important mechanism of concrete deterioration, whereby reactive silica in aggregate interacts with cement alkalis to form expanding gel, which compromises the structural integrity of the concrete. Although the Republic of Korea has historically been classified as a low-risk region for ASR due to its geological stability, documented examples of concrete damage since the late 1990s have necessitated a rigorous reassessment of local aggregates. This study evaluated the ASR potential of 84 aggregate samples sourced from diverse Korean geological regions using standardized protocols, including ASTM C 1260 for mortar bar expansion and ASTM C 289 for chemical reactivity, supplemented by soundness, acid drainage, and weathering index analyses. The results indicate expansion within the range of 0.1–0.2%, classified as potentially deleterious, for some rock types. In addition to ASR reactivity, isolated high anomalies (e.g., high soundness, acid producing, and weathering) suggest the existence of other durability risks. Consequently, while Korean aggregates predominantly have a low ASR reactivity, the adoption of various validated ASR tests as a routine test and the integration of supplementary cementitious materials are recommended to ensure long-term concrete durability, highlighting the need for sustained monitoring and further investigation into mitigation strategies.