裂隙岩體之應力相關水力特性推估為地球科學與相關產業之關鍵研究課題。本研究將利用YOKO 2量測單一裂隙力學內寬(裂隙空隙體積除以裂隙面積)，因此，隨著圍壓增加導致之裂隙閉合，即可順利量測，進而獲得正向應力-裂隙閉合曲線。同時，YOKO 2系統可量測流體流經裂隙之流量，進一步推估裂隙之水力內寬。因水力內寬是推估地下流體流經裂隙之關鍵參數，因此，建立力學內寬與水力內寬間之關係，即顯得極端重要。為達此一目標，本計畫將修改YOKO 2的設計，以達成裂隙體積與流量可利用同一顆試體進行量測。上述物理量，均與裂隙粗糙度有關，本研究將嘗試製作不同粗糙度的金屬與不同岩石之裂隙面，利用三維掃描儀量化粗糙度，並進行裂隙體積與流量量測，以深入探討粗糙度對上述物理量之影響。本計畫成果將成為了解地殼地下流體移棲現象的基礎。 ;The stress-dependent permeability of rock mass is a key issue of scientific or industrial study of geosciences. Hydro-mechanical behaviour of single rock joint will be studied using the YOKO 2 system under high confining pressure. To understand the normal stress effect on fluid flow through a single facture, the joint closure model will be proposed based on the measured (mechanical) closure of fracture resulting from the decreased void spaces when the confining stress increased. In addition, when the effect of fracture roughness and contact area is taken into account, the modified cubic law can be used to predict the fluid flow through rock fracture. As a result, the correlation between hydraulic and mechanical apertures can be identified under a confining stress up to 120 MPa. The results of this fundamental study will highly relevant to the understandings of fluid flow through the crust from shallow to a great depth.
