Study on maintenance for RC road bridge deck deteriorated by deicing salt

2014 Fiscal Year Final Research Report

• Project/Area Number: 24360184
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Structural engineering/Earthquake engineering/Maintenance management engineering
• Research Institution: Nihon University
• Principal Investigator: IWAKI Ichiro 日本大学, 工学部, 教授 (20282113)
• Co-Investigator(Kenkyū-buntansha): KODA Yasuhiro 日本大学, 工学部, 准教授 (40328696) ; KAMIHARAKO Akihisa 弘前大学, 理工学研究科, 准教授 (70333713) ; NAITO Hideki 東北大学, 工学研究科, 准教授 (50361142) ; HANEHARA Syunsuke 岩手大学, 工学部, 教授 (10400178)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 道路橋RC床版 / 疲労 / 凍結防止剤 / 塩害 / ASR / 輪荷重走行試験 / 強制振動試験

Outline of Final Research Achievements

Recently, reinforced concrete road bridge decks are being damaged by fatigue due to vehicle loadings and chloride induced deterioration and/or ASR due to deicing salt. The aim of this study is to solve the mechanism for RC deck deteriorated by deicing salt and develop its maintenance technology.
Firstly, using full-sized RC deck specimens, accelerating tests for chloride induced deterioration and wheel load trucking test were conducted. These experimental results revealed that the fatigue resistance of RC bridge deck was clearly declined even if the corrosion rate of rebar was low, and the corrosion of upper rebars would be the dominant factor in the fatigue resistance of RC bridge deck.
Next, ASR accelerated tests and wheel load trucking test were conducted. It was revealed that the fatigue resistance of RC bridge deck by ASR depended on the reaction velocity of ASR. Furthermore, a vibration test proved useful in evaluating the fatigue resistance of RC bridge deck by ASR.

Free Research Field

コンクリート工学，社会インフラメンテナンス工学