Clarification of fracturing mechanism by expansive cement agent and basic examination far making an alarm unit to predict an accidental discharge using acoustic emission monitoring

澄清膨胀水泥剂的压裂机理和基础检查，远距离使用声发射监测来预测意外放电的警报装置

• 批准号: 13650986
• 负责人: ISHIDA Tsuyoshi
• 金额: $ 2.05万
• 依托单位: Yamaguchi University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13650986/
• 关键词: expansive cement agent; acoustic emission; thermal stress; rock mechanics; 静的破砕剤

Calcium oxide (CaO)-based expansive cement, also known as "non-explosive demolition agents", has been widely used to fracture massive rocks and concrete structures. To clarify its fracture mechanism, we made an experiment to fracture a mortar specimen of 200 mm and 300 mm cubic by setting calcium oxide-based expansive cement in a 50 mm diameter hole bored in the center of the specimen. AE (acoustic emission) sources clustered in outside of the specimen rather than vicinity of the hole just before macroscopic cracks generated, suggesting that macroscopic cracks originated at the outside of the specimen and then extended inward. Although the expansive pressure causes tensile stress in tangential direction of the hole, the stress is the maximum in the hole wall and decrease in proportion to square of the distance from the hole. On the other hand, thermal stress due to heating of the hole is tensile in the outside of the specimen but it is compressive in the vicinity of the hole. Thus, it could be concluded that thermal stress has large effects in the fracture caused by calcium oxide-based expansive cement, at least, in a rock or concrete block without preexisting crack

氧化钙（CaO）基膨胀水泥，也被称为“非爆炸性爆破剂”，已广泛用于破坏大块岩石和混凝土结构。为了弄清其断裂机理，我们在200 mm和300 mm立方的砂浆试件中心钻一个直径为50 mm的孔，在孔内注入氧化钙基膨胀水泥，对其进行了断裂实验。在宏观裂纹产生之前，AE（声发射）源聚集在试件外侧，而不是孔附近，说明宏观裂纹起源于试件外侧，然后向内扩展。膨胀压力在井眼切向产生拉应力，但在井壁处应力最大，且随距井眼距离的平方成比例减小。另一方面，由于孔的加热引起的热应力在试样的外部是拉伸的，但在孔附近是压缩的。由此可见，热应力对氧化钙基膨胀水泥造成的裂缝影响较大，至少对没有裂缝的岩石或混凝土块而言是如此

项目成果

末宗克浩, 石田毅, 木下直人, 福井久明: "岩石加熱試験と比較した静的破砕剤の熱応力による破砕効果"土木会第33回岩盤力学に関するシンポジウム講演論文集. 385-390 (2004)

Katsuhiro Suemune、Takeshi Ishida、Naoto Kinoshita、Hisaaki Fukui：“与岩石加热试验相比，静态破碎剂热应力引起的断裂效应”第 33 届岩石力学研讨会论文集，日本土木工程学会 385-390（2004 年）。

末宗克浩, 田口雅輝, 石田毅, 大坂直哉, 福井久明, 水田義明: "静的破砕剤によるモルタル破壊のAE測定と熱応力解析"土木学会中国支部平成14年度研究発表会発表概要集. 365-366 (2002)

Katsuhiro Suemune、Masateru Taguchi、Takeshi Ishida、Naoya Osaka、Hisaaki Fukui、Yoshiaki Mizuta：“静态破碎剂对砂浆断裂的AE测量和热应力分析”日本学会中国分会2002年研究报告的演讲摘要土木工程师 365 -366 (2002)

福井久明, 石田毅, 大坂直哉: "静的破砕剤によるモルタル供試体破壊時のAE測定"火薬学会誌. 65巻1号. 21-24 (2004)

Hisaaki Fukui、Takeshi Ishida、Naoya Osaka：“使用静态破碎剂进行砂浆样品断裂时的声发射测量”，日本炸药学会杂志，第 65 卷，第 1. 21-24 期（2004 年）。

Ishida, T., Taguchi, M., Suemune, K, Fukui, H., Mizuta, Y.: "Fracturing mechanism by expansive cement agent deduced from acoustic emission monitoring"Proc.of 2002 ISRM Regional Symposium (3rd Korea-Japan Joint Symposium) on Rock Engineering Problems and A

Ishida, T.、Taguchi, M.、Suemune, K、Fukui, H.、Mizuta, Y.：“通过声发射监测推断的膨胀水泥剂的压裂机理”2002年ISRM地区研讨会（第3届韩日联合）会议记录

Ishida, T., Taguchi, M., Suemune, K, Fukui, H., Mizuta, Y.: "Fracturing mechanism by expansive cement agent deduced from acoustic emission monitoring"Proc.of 2002 ISRM Regional Symposium (3rd Korea-Japan Joint Symposium)on Rock Engineering Problems and Ap

Ishida, T.、Taguchi, M.、Suemune, K、Fukui, H.、Mizuta, Y.：“通过声发射监测推断的膨胀水泥剂的压裂机理”2002年ISRM地区研讨会（第3届韩日联合）会议记录