Clarification of causes of redegradation after ASR repair measures and proposal of repair strategies based on the findings

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04549
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22010:Civil engineering material, execution and construction management-related
• Research Institution: Kanazawa University
• Principal Investigator: KUBO YOSHIMORI 金沢大学, 地球社会基盤学系, 准教授 (50324108)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 維持管理 / ASR / コンクリート / アルカリ骨材反応 / 凍結防止剤 / 表面含浸工法

Outline of Final Research Achievements

ASR degradation is one of the causes of concrete deterioration, and there are many cases of redegradation after remedial measures. In order to clarify the causes of such redegradation, various investigations and monitoring of the structures after repair measures were conducted. The repair with surface protection without mechanical restraint was found to be effective even under the severe environment of anti-freeze application, and the importance of controlling the water supply on the back side was clarified. In the case of mechanical restraint, the importance of maintenance combined with monitoring to verify the effectiveness of the measures was clarified.

Free Research Field

土木材料、施工および建設マネジメント関連

Academic Significance and Societal Importance of the Research Achievements

ASR劣化は対策後に再劣化が生じやすく、維持管理対策が難しい劣化の一つである。他方、再劣化の原因の解明は十分でなく、対策効果の検証が行われた事例は少ない。本研究ででは、補修対策の効果検証に主眼を置き、有効な補修戦略に対する成果を得た。膨大なコンクリート構造物の維持管理において、それらの成果は、ASR劣化構造物のより効率的および効果的な補修対策の選定および実施、さらにはその後の維持管理に関して大きく貢献するものとなる。