Evaluation method of ASR reactivity of aggregate and remained expansion by Raman spectroscopy

2021 Fiscal Year Final Research Report

• Project/Area Number: 19H02214
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 22010:Civil engineering material, execution and construction management-related
• Research Institution: Kyoto University
• Principal Investigator: Yamamoto Takashi 京都大学, 経営管理研究部, 教授 (70335199)
• Co-Investigator(Kenkyū-buntansha): 三浦 泰人 名古屋大学, 工学研究科, 准教授 (10718688) ; 上田 尚史 関西大学, 環境都市工学部, 准教授 (20422785) ; 高谷 哲 京都大学, 工学研究科, 助教 (40554209)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: ASR / 反応性骨材 / ラマン分光分析

Outline of Final Research Achievements

In this research project, we focus on Raman spectroscopy as a method that can quickly and easily measure the ASR reactivity of aggregates, and aim to establish a method for evaluating the ASR reactivity of aggregates and the amount of remaining expansion. Since it has been confirmed that the ASR reaction product does not expand due to water absorption and the amount of water absorption expansion of the reactive aggregate itself is large, ASR is considered to be caused by silica dissolved from the aggregate filling voids and not being able to mitigate expansion due to water absorption of the aggregate. In addition, it has been found that the Raman spectrum of aggregates that are easy to dissolve has strong fluorescence caused by non-crosslinked Si-O in the low wave number side , and that are easy to expand due to water absorption has strong fluorescence of glass.

Free Research Field

土木材料・施工・建設マネジメント

Academic Significance and Societal Importance of the Research Achievements

ASRのメカニズムや反応性骨材についてはこれまでにも様々な検討がなされており，ASRの抑制に関しても一定の成果は得られている．しかし，コンクリート用骨材には，多種多様な岩種が用いられており，既存の骨材反応性試験のもとでこれまで反応性を持たないとされていた骨材で，遅延膨張性と考えられる膨張およびひび割れを発生した例も報告されている．ASRの発生メカニズムを明らかにし，骨材のASR反応性を的確に評価する技術を確立することは，コンクリート構造物の長寿命化に貢献するものであり，社会的意義も大きいと考えられる．