• 作者： 石作?; 梁建銓
• 作者服務機構： 國立成功大學礦業及石油工程學系; 國立成功大學礦冶研究所
• 中文摘要： 本文係以實驗方法，首先求取青昌山白雲石之各項物理性質及彈性常數，繼以潛變實驗方式求取白雲石之終端強度、臨界應變量及穩定潛變率、截距與作用應力間之關係；並藉此找出預測該類岩石破壞時間之實驗式，以利將來地下坑內開採時之規劃設計及開採進行中坑內支撐之依據。 潛變實驗除採用原有之CT-180器材外，並利用卡佛式油壓機，配合自行設計之壓力增強變換器及氮氣鋼瓶一組器材分別進行，並得下列諸結果： (1)白雲石係顆粒細，比重大，岩性強之緻密岩石，其瞬間彈性應變量較潛變應變量大甚多，且其間之比值隨作用應力之增加而降低，其間之關係成一反比之指數曲線，(方程式無法摘錄) =K，式中 α, K均為常數，εR為瞬間彈性應變與潛變應變之比值。 (2)白雲石之終端強度介於單軸向抗壓強度45～62%之間。 (3)白雲石岩樣在各階應力作用下之彈性模數E，均略隨應力之增加而增加，至岩樣之破碎應力作用時，則略見降低或不穩定。白雲石之模數比（modulus rafio, E/qu）值為606，略顯偏高，此顯示白雲石之結晶程度極佳。 (4)白雲石岩樣在恒壓下之潛變應變與時間之關係，可以公式ε=K.tb表示之，其中b=0.180為定值，K值隨作用應力之增減而增減。 (5)白雲石之穩定潛變率n與作用應力σ之全對數間成一良好之直線關係： n×10-8=3.565×10-20×σ3.0699 (6)白雲石單位時間之潛變率b1與作用應力σ之全對數為一直線關係： b1×10-6=7.495×10-14×σl·9086 (7)白雲石之穩定潛變應變在應變軸上之栽距C，與應力σ間之全對數，亦成一直線關係： C×10-6=5.178×10-13×3Xσ1.951 (8)白雲石之臨界應變值約為l,986.75×10-6 in/in。藉臨界應變、截距觀念及潛變實驗數據，可導出預測白雲石破壞之時間公式，其中以 (方程式無法摘錄) 式之實用性較高，且能合乎工程安全條件，所得之預測值與實際值之誤差，較低者為14.7%，較高者為60%。反之，並可利用該式來預測岩樣在破壞時之應變量，所得之誤差僅1.78%。
• 英文摘要： This paper is primarily concerned with thecreep characteristics of dolomite samples fromthe Chin-Chan-Shan Dolomite Mine in HualienHsien, Taiwan. Other physical and elasticproperties such as uniaxial and triaxial com-pression, shear, splitting and flexural strength,apparent specific gravity, absorption of water,apparent porosity, slake durability, elastic mod-ulus and Poisson's ratio were also tested. The creep tests were conducted on BX andAX core samples using a CT-180 creep appa-ratus with a new design pressure intensifierunder a constant load condition. The followingconclusions are made from the test results: (1) Strength, specific gravity, slake durabil-ity index and elastic modulus of the dolomiteare comparatively high, but the apparent po-rosity and absorption of water are low. (2) The instantaneous elastic strain (ε1) ofthe dolomite is much greater than the creepstrain (ε2). The ratio of εl/ε2 increased expo-nentially as the stress decreased. (3) The long ternm strength of the dolo-mite is fallen within the range of 45.2% to62.0% of the uniaxial compressive strength. (4) The modulus of elasticity (E) of thedolomite between each increasing stress intervalincreased in correlation with the increase of theapplied stress level. (5) The relationship between the creepstrain (ε) of dolomite and the creep time (t)satisfies the power equation: ε=k.tb where b=0.180 is a constant, and k varies with appliedstress for dolomite. (6) The relationships between the appliedstress (σ), the creep rate (b1), intercept (C) andthe steady state creep rate (n) may be presentedas the following power equations respectively: b1×10-6=7.495×10-14×σ1.9086 C×10-6=5.178×10-13×σ1.951 n×10-18=3.565×10-20×σ3.0699 (7) The critical strain of the dolomite wasdetermined to be 1,986.75×10-6 in./in. Basedon this value, the failure time of dolomite understressed conditions may be predicted. The devi-ation between the predicted value and the valuescalculating from the test data are 14.7% mini-mum and 60.0% maximum. Also under theknown stressed conditions, the critical strain atfailure of dolomite can be predicted at a devia-tion of 1.78% as compare with the actual failurevalue.
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