Study On The Characteristic Of Wave Propagation And Damage In Non-Consecutive Joint Media

Many geotechnical dynamic problems exist in geotechnical engineering, plenty of which refer wave propagation, in which the most complex and outstanding problem is the wave propagation on cranny. The significance of this study lies in the beneficial probing and experimental study on wave propagation in cracked media under static load the first time.This research is mainly focused on the influence of crack on the wave propagation in cracked media under static load. Firstly, according to the joint stiffness described with M-C law, the behavior of the wave propagation through the different joint is discussed systematically. Then the interaction between stress wave and slipping rock interface described with joint stiffness is discussed, and the general formula to calculate the amplitudes of reflected and transmitted wave is given. Adopting plaster and cement with sand to make intermittent cracked Rock-like samples, wave propagation characteristic through cracked samples with different crack obliquity is tested with supersonic wave apparatus. The attenuation rule of the wave velocity and amplitude under different stress level with stress and strain control mode are tested, and analyzed and the strength change rule under different crack obliquity is analyzed .It is found that the wave velocity is not sensitive with stress; the amplitude is sensitive with stress level, and the amplitude can reflect the damage process under load. The intension of the sample is greatly effected by the connectivity rate. Then, as a usage of the test result above, the damage model is put forward and the damage tensor is got. Lastly, the model is validated through uniaxial static test.