研究期間：10108~10207;The purpose of this project focuses on the measurement of sound wave and acceleration generated by rock fracture or landslide with acoustic sensor and accelerometer, and the establishment of early-warning mechanism of calamity. When the sliding of fault or the landslide occurs, the energy is transmitted relying on vibration of particles. In addition to a vibration, the differently natural sound waves will be produced at this moment. This project prepares to monitor the deformation and failure in soils and rocks by a measurement system of sound wave and acceleration. Furthermore, this project will explore the small sound wave and the little vibration before generating a large deformation or failure in soils and rocks, and the information of sound wave and the vibration can be used to predict the occurrence of calamity. Firstly, this project is expected to carry out the wave propagation test of sound and acceleration in soil medium with a large-scale indoor test pit. And then the artificial rock blocks will be prepared with Shiluo sands and cements under different mass ratios. The acoustic sensor and accelerometer are inserted into the artificial rock blocks. A series of rock friction tests and rock fracture tests will be carried out by adopting a method of strain control or stress control. However, the soil specimens are made of Shiluo sands and fine aggregates with different mass ratios. A series of friction tests between soil specimens and artificial rock blocks or soil shear tests will be carried out by a same method of strain control or stress control. This project focuses on the capture of sound waves and accelerations during the testing process in order to understand the signal characteristics in rocks or soils when rocks or soils are subject to shear stress. The relationships among sound waves, accelerations, friction stress and displacements will be established. Furthermore, the signals of sound waves and accelerations will be analyzed by the application of HHT and FFT. This project anticipates developing the early-warning mechanism by observing the little variety of sound waves and the acceleration. This early-warning mechanism will improve effectively the timeliness and reliability of the present early-warning systems. We look forward to this early-warning mechanism can reduce the influence of calamity and ensure people's lives and properties against accidents.
