Yang G.-F.,Beijing Research Institute of Uranium Geology
Applied Mechanics and Materials | Year: 2014
On January 2, 2014, had the thermal infrared remote sensing image (TASI) near the drain of the Chang Jiang nuclear power station in Hainan Province plant. Due to the effect of external factors, such as the sun azimuth, the data within a single band appeared brightness gradient phenomenon. It was not conducive to the seawater temperature retrieval. Through research and analysis, established a model for thermal infrared image brightness gradient of the seawater. Based on quadratic polynomial fitting method, simulated the law of each kind of water after threshold classification, and then used the simulated compensation correction factors to correct the original image, had obtained a good application effect. © (2014) Trans Tech Publications, Switzerland.
Li Z.-W.,Beijing Research Institute of Uranium Geology
Wutan Huatan Jisuan Jishu | Year: 2015
Rayleigh wave exploration method is used in various fields of engineering survey widely, and a fast and accurate Rayleigh wave dispersion imaging method is one of the key factors in Rayleigh wave method. This paper introduce three dispersion imaging methods implementation in detail by synthetic data, and analysis the dispersion imaging results of different imaging methods, by comparison, we can clearly see the Rayleigh wave distribution of energy in the imaging results of F-K transform method and τ-p transform method, but it is not conducive to the dispersion curve extraction, and the phase shift method has better dispersion imaging results, and can get a higher frequency and higher order Rayleigh wave dispersion curves.
Meng D.-L.,Shanghai University |
Sun D.-A.,Shanghai University |
Liu Y.-M.,Beijing Research Institute of Uranium Geology
Yantu Lixue/Rock and Soil Mechanics | Year: 2012
The filter paper method and the pressure plate method are used for measuring the suction of Gaomiaozi bentonite-sand mixtures. The soil-water characteristic curves (SWCC) obtained during drying from the tests at different void ratios and different mixing ratios of Gaomiaozi bentonite to Fujian sand are compared. The effects of void ratio and the mixing ratio on SWCC are analyzed according to the test results. The results show that when the SWCC is expressed by the relation between suction and saturation degree, the SWCC moves up and right with the decreasing void ratio for a mixture with the same mixing ratio. That's to say, the saturation degree increases with the decreasing void ratio at a constant suction. Especially when the suction is less than 10 MPa, this phenomenon is evident; at constant void ratios, the SWCC moves up and right while increasing the mixing ratio. In other words, the value of air-entry suction increases with the increasing mixing ratio. In addition, when the mixing ratio and void ratio are the same, the SWCCs of Gaomiaozi bentonite-sand mixture and Kunigel bentonite-sand mixture are quite similar.
Cai M.,Laurentian University |
Zhao X.,Beijing Research Institute of Uranium Geology |
Kaiser P.K.,Center for Excellence in Mining Innovation
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2014
It is widely accepted that the field or in-situ strength of massive rocks is approximately (0.4±0.1) σc, where σc is the uniaxial compressive strength obtained from unconfined laboratory tests. In addition, it has been suggested that the in-situ rock spalling strength, i.e. the strength of the wall of an excavation when spalling initiates, can be set to the crack initiation stress determined from laboratory test or field microseismic monitoring. These findings were based on either Kirsch's solution or simplified numerical stress modeling(with smooth tunnel wall boundary) to approximate the maximum tangential stress σmax at the excavation boundary. In this article, it is suggested that these approaches ignore one of the most important factors, the irregularity of the excavation boundary. It is demonstrated that the "actual" in-situ spalling strength of massive rocks is not equal to (0.4±0.1) σc, but can be as high as (0.8±0.05) σc when surface irregularities are considered. It is demonstrated using the Mine-by tunnel notch breakout example that when the realistic "as-built" excavation boundary condition is honored, the "actual" in-situ rock mass strength, given by 0.8 σc, can be applied to simulate progressive brittle rock failure process satisfactorily. We conclude that the interpreted, reduced in-situ rock mass strength of (0.4±0.1) σc without considering geometry irregularity is therefore only an "apparent" rock mass strength.
Wang J.,Beijing Research Institute of Uranium Geology
Journal of Rock Mechanics and Geotechnical Engineering | Year: 2014
Underground research laboratories (URLs), including "generic URLs" and "site-specific URLs", are underground facilities in which characterisation, testing, technology development, and/or demonstration activities are carried out in support of the development of geological repositories for high-level radioactive waste (HLW) disposal. In addition to the generic URL and site-specific URL, a concept of "area-specific URL", or the third type of URL, is proposed in this paper. It is referred to as the facility that is built at a site within an area that is considered as a potential area for HLW repository or built at a place near the future repository site, and may be regarded as a precursor to the development of a repository at the site. It acts as a "generic URL", but also acts as a "site-specific URL" to some extent. Considering the current situation in China, the most suitable option is to build an "area-specific URL" in Beishan area, the first priority region for China's high-level waste repository. With this strategy, the goal to build China's URL by 2020 may be achieved, but the time left is limited. © 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences.