A study on establishing waterproofing system combining pavement, waterproof layer and concrete slab

2019 Fiscal Year Final Research Report

• Project/Area Number: 18K13811
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 22010:Civil engineering material, execution and construction management-related
• Research Institution: Central Research Institute of Electric Power Industry (2019); Yokohama National University (2018)
• Principal Investigator: Komatsu Satoshi 一般財団法人電力中央研究所, 地球工学研究所, 主任研究員 (00732869)
• Project Period (FY): 2018-04-01 – 2020-03-31
• Keywords: コンクリート床版 / 防水層 / アスファルト舗装 / 数値シミュレーション / 温度応力 / 水蒸気圧

Outline of Final Research Achievements

In this research, generation of microcracks were confirmed by an experimental work in which the heat generated from asphalt pavement being laid was applied to upper surface of concrete. In addition, a shear fatigue test simulating vehicle loads was conducted on the concrete specimen with the microcracks. Furthermore, a numerical simulation was carried out to reveal the mechanism of the microcracks generation.
As the results, first, the microcracks were generated 1 to 2 mm from the upper surface of concrete in several cases. As the counter measures, decreasing moisture contents of concrete, removing weak part in upper surface of concrete and securing sufficient amount of air content in concrete were proposed. Second, the microcracks could lead to unexpected deterioration of pavement. Third, the microcracks were generated when thermal stress and pore pressure in concrete were sufficiently increased, simultaneously.

Free Research Field

コンクリート工学

Academic Significance and Societal Importance of the Research Achievements

防水層はコンクリート床版への水の浸入を防ぐ目的で開発が進み，現場に敷設されてきている．しかし，今回の一連の検討結果から，コンクリートに存在する（入った）水が逃げるという観点で見直すと，防水層が不利に働く場合があることが示された．本研究成果は防水層の開発の一つの方向性を示しているだけでなく，舗装・防水層・コンクリートが一体となって防水システムを考える必要があることを明示していると考えている．