LEAKAGE MONITORING FOR FACE SLABS OF CFRDs
In recent concrete face rockfill dams (CFRDs), small deflections have been achieved by forming a well-compacted rockfill embankment and through careful design and construction of all details. Therefore, the CFRD has become one of the most common dam types, and the number of CFRDs is increasing worldwide. In Japan, we started to investigate the design and construction of CFRDs with vibratory compaction of rock materials in small and controlled layers several years ago, and have constructed several small CFRDs with a height of around 30 m. Because of the lack of experience of design and construction of CFRDs as well as special social conditions in Japan, there is a strong need for precise monitoring of the leakage through joints of face slabs and cracks generated in them caused by the deflection of the upstream slope. However, since waterstops are installed at slab joints and fly ash is placed immediately upstream of joints to prevent leakage through them, detectors are needed for detecting the leakage through the cracks in face slabs. We therefore conducted fundamental large-scale tests to develop a cable-shaped leakage detector utilizing the difference in characteristic impedances of the media surrounding the detector. The leakage detector was improved based on the results of large-scale tests and installed in the Tomata Saddle Dam, a CFRD type. In this paper, we introduce the mechanism of the leakage detector, and report the detailed method and results of the tests. We also describe the installation of detectors and measured results in the Tomata Saddle Dam.
CFRD Leakage Slab Cracks Leakage detector
Toshihide Kobori Yoshikazu Yamaguchi Tadahiko Sakamoto
Public Works Research Institute 1-6, Minamihara, Tsukuba-shi, Ibaraki-ken, 305-8516,Japan Public Works Research Institute 1-6, Minamihara, Tsukuba-shi, Ibaraki-ken, 305-8516, Japan
国际会议
西安
英文
1-9
2005-11-01（万方平台首次上网日期，不代表论文的发表时间）