DOI QR코드

DOI QR Code

A STUDY OF THE PRESSURE SOLUTION AND DEFORMATION OF QUARTZ CRYSTALS AT HIGH pH AND UNDER HIGH STRESS

  • Choi, Jung-Hae (Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources) ;
  • Seo, Yong-Seok (Department of Earth and Environmental Sciences, Chungbuk National University) ;
  • Chae, Byung-Gon (Geologic Environment Division, Korea Institute of Geoscience and Mineral Resources)
  • 투고 : 2012.03.27
  • 심사 : 2012.08.14
  • 발행 : 2013.02.25

초록

Bentonite is generally used as a buffer material in high-level radioactive waste disposal facilities and consists of 50% quartz by weight. Quartz strongly affects the behavior of bentonite over very long periods. For this reason, quartz dissolution experiment was performed under high-pressure and high-alkalinity conditions based on the conditions found in a high-level radioactive waste disposal facility located deep underground. In this study, two quartz dissolution experiments were conducted on 1) quartz beads under low-pressure and high-alkalinity conditions and 2) a single quartz crystal under high-pressure and high-alkalinity conditions. Following the experiments, a confocal laser scanning microscope (CLSM) was used to observe the surfaces of experimental samples. Numerical analyses using the finite element method (FEM) were also performed to quantify the deformation of contact area. Quartz dissolution was observed in both experiments. This deformation was due to a concentrated compressive stress field, as indicated by the quartz deformation of the contact area through the FEM analysis. According to the numerical results, a high compressive stress field acted upon the neighboring contact area, which showed a rapid dissolution rate compared to other areas of the sample.

키워드

참고문헌

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피인용 문헌

  1. Application of hybrid numerical and analytical solutions for the simulation of coupled thermal, hydraulic, mechanical and chemical processes during fluid flow through a fractured rock vol.74, pp.12, 2015, https://doi.org/10.1007/s12665-015-4769-9