Study on Accuracy Improvement of Deflection Measurement in Evaluating the Soundness of Road Bridge Slabs Using FWD

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04561
• 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: Kindai University
• Principal Investigator: Higashiyama Hiroshi 近畿大学, 理工学部, 教授 (60319754)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 道路橋床版 / アスファルト舗装 / 健全度評価 / たわみ

Outline of Final Research Achievements

In the proper soundness evaluation of road bridge slabs using FWD, it is important to correct the deflection of slabs to account for the influence of stiffness of the asphalt pavement, which depends on its temperature.
In this study, the temperature measurement inside asphalt pavements on concrete slabs was conducted over a period of one year using specimens that simulated actual bridge slabs. From the measurement results, using some models that can estimate the average temperature of the asphalt pavements on the slabs, the predicting accuracy was compared among them. Consequently, it was confirmed that the predicting model can be used in the practical measurement using FWD. Next, FWD tests were conducted on specimens simulating real bridge slabs. The correction method proposed was verified using the measured deflection. The results revealed that the deflection after correcting was estimated with an error of approximately 10% against the measured deflection.

Free Research Field

橋梁工学

Academic Significance and Societal Importance of the Research Achievements

道路橋床版の適切な維持管理が求められるなか、その健全度評価を効率的かつ定量的に実施していくことが重要となっている。しかし、これまでの研究では、FWDを用いた定量的な健全度評価方法が確立されてきたとは言えない。そこで本研究では、床版上のアスファルト舗装の平均温度推定と重錘落下時における舗装の変形を考慮したたわみ補正方法を構築するとともに、その補正精度は社会実装を可能とするレベルであることを確認した。
よって、道路橋床版の健全度を定量的に評価できる方法の構築ができたと言え、今後の道路橋床版の維持管理に大いに活用できると考えている。