Investigation and modeling of mechanical characteristics of non-uniform and discontinuous rock mass in deep ground by in-situ triaxial tests

原位三轴试验研究深部非均匀不连续岩体力学特性并建模

基本信息

批准号：
13355021
负责人：
TANI Kazuo
金额：
$ 17.97万
依托单位：
National University Corporation Yokohama National University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2004
项目状态：
已结题

项目摘要

In-situ triaxial test method was invented in 1998 for the purpose to measure average stress and strain relationships of rock masses. Since the test specimens are prepared in the ground by rotary drilling, disturbance of the ground is expected to be as practically minimal.In the fiscal year 2001,the advanced version of the test method was devised using CCD for deformation measuring system. This system was expected to allow measurement of strain distribution throughout the test specimen, thus believed to be useful for studying non-uniform or discontinuous rock mass behavior.In the fiscal year 2002,uniaxial as well as triaxial compression devices were developed introducing this CCD measuring system. Furthermore, multi-step loading triaxial test method was investigated to reduce the number of test specimens and to avoid the difficulties of interpreting scattered data.In the fiscal year 2003, a couple of triaxial tests were conducted with CCD measurement using artificial rock specimens. The results demonstrated that the deformation of specimens became progressively localized as the axial compression proceeded. Moreover, test equipment for the field test was improved. The accuracy and speed of deformation measurement were enhanced as ten-fold as the previous version. Selection of site was also made for the field tests and preliminary geological investigation was conductedIn the fiscal year 2004,a series of field tests were carried out at the site of tuff breccia. Average stress and strain relationships were measured for typically non-uniform rock masses. Some laboratory triaxial tests were also done to obtain the complimentary data to study scale effect and some other features of rock mass behavior.

1998年发明了原位三轴测试方法，目的是衡量岩体的平均应力和应变关系。由于测试样品是通过旋转钻孔在地面上制备的，因此地面的干扰实际上是很小的。预计该系统将允许在整个测试样品中测量应变分布，因此被认为可用于研究非均匀或不连续的岩体质量行为。此外，还研究了多步加载三轴测试方法，以减少测试标本的数量并避免解释散射数据的困难。在2003财年，使用人工岩石标本进行了CCD测量，进行了几个三轴测试。结果表明，随着轴向压缩的进行，样品的变形逐渐局部定位。此外，改进了现场测试的测试设备。变形测量的准确性和速度与以前的版本相比提高了十倍。还对现场测试进行了选择，并在2004财政年度进行了初步地质研究，在Tuff Breccia地点进行了一系列现场测试。对于通常不均匀的岩石质量测量了平均应力和应变关系。还进行了一些实验室三轴测试，以获取免费数据以研究规模效应以及岩体行为的其他一些特征。