标题: | 脆性岩石受载过程之声射特性与定位 A Study on the Characteristics and Source Location of Acoustic Emission of Brittle Rocks Subjected to Loading |
作者: | 纪毓中 Yu-Chung Chi 潘以文 Yii-Wen Pan 土木工程学系 |
关键字: | 声射,裂缝;acoustic emission,crack |
公开日期: | 1993 |
摘要: | 脆性岩石在受载的过程中,材料内部原生裂缝尖端可能有应力集中的现象 ,以致造成裂缝的延伸。随着载重的增大,裂缝间可能相互连结,终至形 成一主要裂面导致崩溃破坏。这些裂缝的启动、成长所产生之弹性应力波 ,极易为声射撷取系统所接收、记录。本研究即希望藉助声射量测技术来 探讨受载脆性岩石中裂隙之发展,同时分析不同载重条件下 (单轴压缩试 验、三点载重试验、巴西间接张力试验) 声射讯号之特性。经由本研究试 验结果之分析,得到以下的结论: 1.以声射定位来探讨脆性岩石受载过 程中裂隙之发展,具有其可行性。 2.由变质石英砂岩三种试验结果,归 纳声射数比与振幅、历时、能量的关系,可发现具有一致性的相对大小关 系。 3.脆性岩石在受载过程中,高振幅声射讯号的出现与裂缝的不稳定 成长之间,存在密切的关系。 4.利用声射技术可有效分辨岩石不同的受 载阶段。 The microfractures in a brittle rock may develop or expand when the material is subjected to loading. Microfracturing process in the material will result in elastic waves,which can be detected by an acoustic emission data acquisition system. This thesis aims to investigate the acoustic emission characteristics and the fracturing process under various loading condition (uniaxial compression test, three-point- bending test , Brazilian test ). Conclusions are drawn from the study: 1.It seems feasible to use acoustic emission source location technique to investigate the crack developing process of a brittle rock Subjected to loading. 2.For the sample used in the study, it is found that the relative order of the amplitude ,duration ,energy level of acoustic emissions occur in various loading types are all similar. 3.In general, acoustic emission of the highest amplitude tends to occurs in the stage of unstable crack propagation. 4.Different loading stages can be identified effectively by the acoustic emission technique. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#NT820015017 http://hdl.handle.net/11536/57532 |
显示于类别: | Thesis |