Abstract:Based on the grade blocks tectonic theory for discontinuous and self-stress rock mass in depth,the effect of block-rock hierarchy scale on pendulum-type wave propagation is studied. Acceleration response of every block-rock is solved in the block-rock dynamical model on shock loading. Acceleration and frequency characteristics including center frequency and center frequency bandwidth of the block-rock mass are calculated,under the same shock loading energy and different block-rocks scales. The comparison results show that,the higher grade of block-rock structures,the more fast attenuation of block-rock mass acceleration on shock loading,and the main attenuation area is focus on the initial area of the block-rock structures. Pendulum-type wave is a low velocity wave while propagation in the block-rock mass compared with P wave and S wave. The higher grade of block-rock structures,the more lower velocity of pendulum-type wave. Block-rock with a larger frequency band center and wider bandwidth concentrate in the initial area when the higher grade of block-rock structures. The block-rock frequency band center moving to low frequency and the bandwidth becomes smaller on pendulum-type wave propagation,which performance the characteristics of low frequency,however,the changing trend more significantly when the higher grade of block-rock structures. Degree of fragmentation and joint development in rock mass can be inversion by the time-domain and frequency-domain results and testing techniques.
[1] SADOVSKY M A. Natural lumpiness of rocks[J]. Dokl. Akad. Nauk SSSR,1979,247(4):21–29.
[2] KURLENYA M V,OPARIN V N,VOSTRIKOV V I. Formation of elastic wave packages in the block-structured medium under impulse loading pendulum type waves[J]. Dokl. Akad. Nauk SSSR,1993,333(4):1–7.
[3] KURLENYA M V,OPARIN V N,VOSTRIKOV V I. pendulum type waves. part II:experimental methods and main results of physical modeling [J]. Journal of Mining Science,1996,32(4):245–273.
[4] KURLENYA M V,OPARIN V N,VOSTRIKOV V I. Pendulum-type waves. part I:State of the problem and measuring instrument and computer complexes[J]. Journal of Mining Science,1996,32(3):159–163.
[5] KURLENYA M V,OPARIN V N,VOSTRIKOVV I. Rock mechanics. Geomechanical conditions for quasi-resonances in geomaterials and block media[J]. Journal of Mining Science,1998,34(5):379–386.
[6] ALEKSANDROVA N I. Elastic wave propagation in block medium under impulse loading[J]. Journal of Mining Science,2003,39(6):556–564.
[7] ALEKSANDROVA N I,SHER E N. Modeling of wave propagation in block media[J]. Journal of Mining Science,2004,40(6):579–587.
[8] ALEKSANDROVA N I,CHERNIKOV A G,SHER E N. Experimental investigation into the one-dimensional calculated model of wave propagation in block medium[J]. Journal of Mining Science,2005,41(3):232–239.
[9] ALEKSANDROVA N I,CHERNIKOV A G.,SHER E N. On attenuation of pendulum-type waves in a block rock mass [J]. Journal of Mining Science,2006,42(5):468–475.
[10] SHER E N,ALEKSANDROVA N I,AYZENBERG-STEPANENKO M V,et al. Influence of the block-hierarchical structure of rocks on the peculiarities of seismic wave propagation[J]. Journal of Mining Science,2007,43(6):585–591.
[11] ALEKSANDROVA N I,SHER E N,CHERNIKO A G. Effect of viscosity of partings in block-hierarchical media on propagation of low frequency pendulum waves[J]. Journal of Mining Science,2008,44(3):225–234.
[12] ALEKSANDROVA N I,AYZENBERG-STEPANENKO M V,SHER E N. Modeling the elastic wave propagation in a block medium under the impulse loading[J]. Journal of Mining Science,2009,45(5):427–437.
[13] OPARIN V N,SIMONOV B F. Nonlinear deformation-wave processes in the vibrational oil geotechnologies[J]. Journal of Mining Science,2010,46(2):95–112.
[14] BAGAEV S N,OPARIN V N,ORLOV V A,et al. Pendulum waves and their singling out in the laser deformograph records of the large earthquakes[J]. Journal of Mining Science,2010,46(3):217–224.
[15] ALEKSANDROVA N I,SHER E N. Wave propagation in the 2D periodical model of a block-structured medium. part I:characteristics of waves under impulsive impact[J]. Journal of Mining Science,2010,46(6):639–649.
[16] 吴 昊,方 秦,于冬勋. 深部块系岩体摆型波现象的研究进展[J].力学进展,2008,38(5):601–609.(WU Hao,FANG Qin,YU Dongxun. Advances in the study on pendulum-type wave phenomenon in the deep block rock mass[J]. Advances in Mechanics,2008,38(5):601–609.(in Chinese))