Experimental Study on Stress Corrosion and Vacuum Effect of Rocks

岩石应力腐蚀与真空效应实验研究

• 批准号: 06452360
• 负责人: OKAMURA Hiroshi
• 金额: $ 4.61万
• 依托单位: Kumamoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06452360/
• 关键词: Rocks; Uniaxial Compression Test; Stress Corrosion; Vacuum Effect; Water Vapor Pressure; Strength of Rocks; 地層処分; 天然バリア; マルチクラック; クリープ強度

At the beginning of the twenty one century, the large rock cavern for radioactive waste diaposal will be constructed within a rock mass at a depth of more than 1000m, in Japan. The stability of such large rock cavern must be guarantee over very long timescale. The prediction of long-term strength of rocks is indispensable for insuring long-term stability of the rock cavern.The strength of rocks under compression is affected by the density, the shape and the direction of cracks, the strain and stress rate of loading, the stress state , the temperature and the existence of water in vapor phase or in liquid phase, and so on. Some researchers have inducated that the strength of rocks in dependent on the subcritical crack growth due to stress corrosion and is proportional to the water vapor pressure in atmosphere. However, few experiments to verify this fact have been performed.In this research, to examine the influence of the water as the stress corrosion agent on the strength of rocks, a … More series of uniaxial compression tests under the water vapor pressure ranging from 10^<-3> to 10^3 Pa is conducted on Kitagishima granite and Kumamoto andesite. Furthermore, the stress corrosion index is determined, then the estimation of long-teem strength of rock is discussed. The main results obtained are follows :1.The elastic modulus are not affected by the stress corrosion due to water vapor, analyzing the stress strain curve obtained.2.The uniaxial compressive strength of both rocks increases with decreasing water vapor pressure. It is clarified that this effect is dependent on the stress corrosion.3.The values of the stress corrosion index obtained from the results are 36 in Kumamoto andesite and 61 in Kitagishima granite, based on the relation between uniaxial compressive strength and water vapor pressure. The linear relation is applicable to the range of water vapor pressure 10^<-3> to 10^3 Pa.4.The estimation of long-term strength of rock is discussed. The discover of an agent activating the stress corrosion is indispensable to estimate the long-term stability of rock cavern. Less

二十一世纪初，日本将在深度超过1000m的岩体中建造用于放射性废物处置的大型岩洞，必须保证这种大型岩洞在很长一段时间内的稳定性。岩石长期强度的预测对于确保岩洞的长期稳定性是必不可少的。受压岩石的强度受密度、裂缝的形状和方向、应变和应力率的影响有研究人员推断，岩石的强度与应力腐蚀引起的亚临界裂纹扩展成正比。然而，很少有实验来验证这一事实。在这项研究中，为了检验水作为应力腐蚀剂对岩石强度的影响，进行了一系列单轴压缩试验。水蒸气压范围为对北木岛花岗岩和熊本安山岩进行了10^<-3>至10^3Pa的应力腐蚀指数测定，并对岩石的长期强度进行了估算，得到的主要结果如下：1。分析得到的应力应变曲线，弹性模量不受水蒸气引起的应力腐蚀的影响。2.两种岩石的单轴抗压强度都随着水蒸气压力的降低而增加，阐明了这种影响是相关的。 3.结果得出的应力腐蚀指数值在熊本安山岩中为36，在北木岛花岗岩中为61，基于单轴抗压强度与水蒸气压力之间的线性关系，适用于。水蒸气压范围为10^-3至10^3Pa。4.讨论了岩石长期强度的估计，应力腐蚀激活剂的发现是必不可少的。估计岩洞的长期稳定性较少。

项目成果

Yuzo Obara: "Rock stress measurement by stress relieving in Japan" Proc.of MMIJ/AusIMM Joint Symposium. 425-432 (1994)

Yuzo Obara：“日本通过应力消除进行岩石应力测量”MMIJ/AusIMM 联合研讨会论文集。

Y.OBARA, K.SUGAWARA: "Influence of water vapor pressure on strength of rocks under uniaxial compression" Proceedings of North American Rock Medianics Symposium. (to be appeared). (1996)

Y.OBARA，K.SUGAWARA：“单轴压缩下水蒸气压力对岩石强度的影响”北美岩石介质学研讨会论文集。

坂口清敏: "コンパクトオーバーコアリング法による岩盤応力の測定" 資源・素材学会誌. 110. 331-336 (1994)

Kiyotoshi Sakaguchi：“通过紧凑型超取芯方法测量岩石应力”日本自然资源与材料学会杂志 110. 331-336 (1994)。

Y.Obara, K.Sugawara and N.Tokashiki: "Influence of water vapor pressure on strength of rocks under uniaxial compression." Proc.of NARMS'96. (to be appeared). (1996)

Y.Obara、K.Sukawara 和 N.Tokashiki：“水蒸气压力对单轴压缩下岩石强度的影响”。

Y.OBARA,K.SUGAWARA: "Influence of water vapor pressure on strength of rocks under uniaxial compression" Proceedings of North American Rock Medranics Symposium. (to be appeared). (1996)

Y.OBARA，K.SUGAWARA：“单轴压缩下水蒸气压对岩石强度的影响”北美岩石医学研讨会论文集。