The dynamic responses such as acceleration, velocity and displacement of geo-materials during fracturing have not received any attention in the fields of geo-engineering and geo-science. The recent advances in measurement, monitoring and logging technologies enable us to measure and monitor the dynamic responses of geo-materials during fracturing. The authors have been carrying such experiments on geo-materials ranging from very soft materials such as clay to hard rocks such as siliceous sandstone by using different loading schemes and loading frames. This article describes some of these experiments and experimental results concerned with the acceleration, velocity and displacement responses of geo-materials during fracturing under laboratory conditions. The velocity and displacement responses are obtained through the EPS integration technique proposed by the authors. We further discuss their implications in geo-engineering and earthquake engineering in relation to permanent surface deformations.
The dynamic responses of geo-materials during fracturing have not received any attention in the fields of geo-engineering and geo-science. However, these responses may be very important in the failure phenomenon of geo-engineering structures (i.e. rockburst, squeezing, sliding) and the ground motions induced by earthquakes. For example, the estimation of the travel distance and path of rock fragments during rockbursts in underground excavations is very important for assessing the safety of workmen and equipments. It is also known that the ground motions induced by earthquakes could be higher in the hangingwall block or mobile side of the causative fault as observed in the 1999 Kocaeli earthquake [1] and the 1999 Chi-chi earthquake[2]. The recent advances in measurement, monitoring and logging technologies enable us to measure and to monitor the dynamic responses of geo-materials during fracturing. Therefore, the studies concerning the dynamic responses of geomaterials during fracturing can now be easily undertaken as compared with that in the past. The authors have been carrying out such a study in recent years. The experiments have been performed on geo-materials ranging from very soft materials such as clay to hard rocks such as siliceous sandstone by using different loading schemes and loading frames [3,4]. This article describes some of these experiments and experimental results concerned with the acceleration responses of geo-materials during fracturing and discuss their implications in geoengineering and earth science.
The experiments have been carried out at the rock mechanics laboratories of three institutes, namely, Tokai University (TU) and Ryukyu University (RU) in Japan and Middle East Technical University (METU) in Turkey [3]. The loading machines of the TU and the RU are low-stiffness machines with a loading capacity of 2000 kN while the loading machine of the METU is a servo-control high stiffness machine with 2000 kN capacity. Figure 1 shows the experimental set-up at two institutes.
