Fundamental study on strength deterioration rate of weathered rocks

风化岩石强度劣化率的基础研究

• 批准号: 05452320
• 负责人: SUGAWARA Katsuhiko
• 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: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-05452320/
• 关键词: Rock; Weathering; Strength deterioration; Fracture toughness; Stress corrosion; Freezing and thawing; 岩石強度劣化; X線CTスキャナ; 弾性波速度; 徴小硬度

Understanding of the composite action of natural environmental factors is indispensable for estimating the stability of rock and rock mass. However, there are unsolved problems for the effect of each factor. Especially, experimental results of the cyclic and cyclic heating are limited in spite of their importance. The present study on the durability of rock and its estimation method consists of three parts as follows :1.Anisotropy effect on fracture toughness of rock.To investigate the anisotropy effect on weathering of rock, the fracture toughness tests according to the suggested method of ISRM are performed, using three type of rock. It has been found out that the pre-existing crack within rock plays an important role in determing the fracture toughness, as well as the longitudinal wave velocity which is proportional to the fracture toughness.2.Experimental study on stress corrosion of rock.The influence of stress, strain rate, temperature and water vapor on the crack propagation in rock has been investigated by the uniaxial compressiontest in a vacuum chamber. The stress corrosion index has been precisely determined and the creep phenomena have been discussed as well as the long-term strength of rock.3.Weathering of rock with freezing and thawing.A cyclic test of freezing and thawing has been performed to make clear the weathering effect on the strength and the mechanical property of rock. In has been shown that the crack propagation in rock is depending upon the speed of freezing and/or thawing, and that a high speed freezing results the crack propagation normal to the free surface, but low speed freezing and thawing produce the cracks parallel to the free surface.

了解自然环境因素的综合作用是评价岩体稳定性的必要条件。然而，各因素的影响都存在未解决的问题。特别是循环加热和循环加热的实验结果虽然重要，但有限。目前对岩石耐久性及其估算方法的研究主要包括以下三个部分：1.岩石耐久性；各向异性对岩石断裂韧性的影响。为了研究岩石的各向异性对风化作用的影响，根据建议的ISRM方法对三种岩石进行了断裂韧性试验。研究发现，岩石内部已存在的裂纹对断裂韧性起着重要的决定作用，纵波速度与断裂韧性成正比。岩石应力腐蚀试验研究。通过真空室单轴压缩试验，研究了应力、应变速率、温度和水蒸气对岩石裂纹扩展的影响。精确地确定了应力腐蚀指数，讨论了蠕变现象以及岩石的长期强度。冻融对岩石的风化作用。为了弄清风化对岩石强度和力学性能的影响，进行了冻融循环试验。研究表明，岩石中的裂纹扩展取决于冻结和/或融化的速度，高速冻结使裂纹垂直于自由面扩展，而低速冻结和融化使裂纹平行于自由面扩展。

项目成果

Eduardo Verdeja: "Three Dimensional Deformation Analysis of Jointed Rock Based on EVDM" Proc.of MMIJ/Aus IMM Joint Symposium. 401-408 (1994)

Eduardo Verdeja：“基于 EVDM 的节理岩石三维变形分析”MMIJ/Aus IMM 联合研讨会论文集。

Katsuaki Koike: "Evaluation of Ground-Water Resource by Integration of Geological and Geophysical Prospecting Information" Proc.of Annual Conference of the Int.Ass.for Mathematical Geology. 194-199 (1994)

Katsuaki Koike：“通过整合地质和地球物理勘探信息评估地下水资源”，国际数学地质学年会论文集。

E.Verdeja, T.Tanaka and K.Kaneko: "Three Dimensional Deformation Analysis of Jointed Rock Based EVDM" New Horizons in Resource Handling and Geo-Engineering. Vol.1. 401-408 (1994)

E.Verdeja、T.Tanaka 和 K.Kaneko：“基于 EVDM 的节理岩石三维变形分析”资源处理和地球工程的新视野。

中山智晴: "画像処理による発破起砕物の粒度分析(その2)" 石灰石. 272. 42-57 (1994)

Tomoharu Nakayama：“通过图像处理对喷砂碎片进行粒度分析（第 2 部分）”石灰石。272. 42-57 (1994)

K.Sakaguchi, K.Sugawara, K.Nagahisa and T.Kaneda: "Application of Conical Ended Borehole Technique to Inhomogeneous Rock and Considerations." Proc.of the 9th Japan Symp.on Rock Mechanics. 229-234 (1994)

K.Sakaguchi、K.Sukawara、K.Nagahisa 和 T.Kaneda：“圆锥端钻孔技术在非均质岩石中的应用及注意事项”。