According to the concept of the fault motion coordination ratio( FCR),this paper discusses the effect of the starting point on the result of FCR calculation and puts forward the calculation method for FCR using the sl...According to the concept of the fault motion coordination ratio( FCR),this paper discusses the effect of the starting point on the result of FCR calculation and puts forward the calculation method for FCR using the sliding window and the index for evaluating the dispersion. Earthquake cases analysis shows that at the Lijiang site across the fault: the FCR value varied greatly and its distribution was dispersive before the MS7. 0 Lijiang earthquake,while the value was stable and less dispersive after the earthquake,which reflects the strain accumulation of the fault during the seismogenic process and the poor movement coordination between the motion of the three components. After the earthquake,the fault was in a free activity state,the accumulated strain energy released, and the movement of the three components was coordinated mutually. At present,FCR dispersion of Lijiang is at a low value,and fault strain accumulation is at a low level.展开更多
Discrete element modeling was used to investigate the effect of particle size distribution on the small strain shear stiffness of granular soils and explore the fundamental mechanism controlling this small strain shea...Discrete element modeling was used to investigate the effect of particle size distribution on the small strain shear stiffness of granular soils and explore the fundamental mechanism controlling this small strain shear stiffness at the particle level. The results indicate that the mean particle size has a negligible effect on the small strain shear modulus. The observed increase of the shear modulus with increasing particle size is caused by a scale effect. It is suggested that the ratio of sample size to the mean particle size should be larger than 11.5 to avoid this possible scale effect. At the same confining pressure and void ratio, the small strain shear modulus decreases as the coefficient of uniformity of the soil increases. The Poisson's ratio decreases with decreasing void ratio and increasing confining pressure instead of being constant as is commonly assumed. Microscopic analyses indicate that the small strain shear stiffness and Poisson's ratio depend uniquely on the soil's coordination number.展开更多
基金funded by the Youth Seismic Regime Tracking Project in the Year of 2012,China Earthquake Administration(2012020203)the Youth Seismic Regime Tracking Project in the Year of 2011(2011020207)the National Key Technology R&D Program of the 12th "Five-year Plan",China
文摘According to the concept of the fault motion coordination ratio( FCR),this paper discusses the effect of the starting point on the result of FCR calculation and puts forward the calculation method for FCR using the sliding window and the index for evaluating the dispersion. Earthquake cases analysis shows that at the Lijiang site across the fault: the FCR value varied greatly and its distribution was dispersive before the MS7. 0 Lijiang earthquake,while the value was stable and less dispersive after the earthquake,which reflects the strain accumulation of the fault during the seismogenic process and the poor movement coordination between the motion of the three components. After the earthquake,the fault was in a free activity state,the accumulated strain energy released, and the movement of the three components was coordinated mutually. At present,FCR dispersion of Lijiang is at a low value,and fault strain accumulation is at a low level.
基金The work presented in this paper was supported by the National Natural Science Foundation of China (Grant Nos. 51308408, 41272291,51238009) and the Fundamental Research Funds for the Central Universities, and the Open Foundation of State Key Labo- ratory of Hydrology-Water Resources and Hydraulic Engineering (Grant No. 2014492311 ).
文摘Discrete element modeling was used to investigate the effect of particle size distribution on the small strain shear stiffness of granular soils and explore the fundamental mechanism controlling this small strain shear stiffness at the particle level. The results indicate that the mean particle size has a negligible effect on the small strain shear modulus. The observed increase of the shear modulus with increasing particle size is caused by a scale effect. It is suggested that the ratio of sample size to the mean particle size should be larger than 11.5 to avoid this possible scale effect. At the same confining pressure and void ratio, the small strain shear modulus decreases as the coefficient of uniformity of the soil increases. The Poisson's ratio decreases with decreasing void ratio and increasing confining pressure instead of being constant as is commonly assumed. Microscopic analyses indicate that the small strain shear stiffness and Poisson's ratio depend uniquely on the soil's coordination number.