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将地壳介质视为马克斯威尔体,运用差分和三维有限元方法,探讨分层地壳结构中分别存在低速体( 软包体) 、高速体( 硬包体) 和同时存在高速体和低速体时地壳应力的集中及应力集中随时间变化的演化特征,计算结果表明:(1) 高速体、低速体的存在引起的平均应力和最大剪应力在高速体内和低速体外集中的结果同理论计算一致;(2) 高速体单独存在时,应力扰动值随时间的变化导致平均应力集中程度在高速体内减弱,最大剪应力集中程度则在高速体内进一步增加,这一特征与地壳的蠕变过程一致,并有利于在高速体内孕育和发生强震;(3) 低速体单独存在时,随着时间的推移,最大剪切应力扰动值在低速体上方逐渐增加,该特征对在低速体上方孕育中等强度地震( 有时也可能是强震) 是很有利的;(4) 高速体和低速体同时存在时,平均应力的集中随时间的推移在高速体也是呈减弱的趋势,而最大剪应力的集中则在高速体内较高速体单独存在时更加显著增加。该项研究的意义在于在非均匀性引起的应力集中的基础上研究应力集中随时间变化,探讨强震孕育过程的机理。
The crustal medium is regarded as Maxwell body, and the differential and three-dimensional finite element method are used to investigate the existence of low-velocity body (soft inclusion body), high-velocity body (hard inclusion body) and high-speed body and low velocity body The results show that: (1) The results of the concentration of the average stress and the maximum shear stress induced by the existence of high-velocity body and low-velocity body in high-speed and low-speed in vitro are consistent with the theoretical calculations; (2) When the high-speed body alone exists, the variation of stress disturbance value with time causes the average stress concentration to weaken in high-speed body and the maximum concentration of shear stress to further increase in high-speed body. This feature is consistent with the creep process of the crust Which is beneficial to the inoculation and occurrence of strong earthquakes in high-speed body. (3) When the low-speed body alone exists, the maximum shear stress disturbance value gradually increases above the low-speed body over time, (Sometimes strong earthquake may be) is very beneficial; (4) high-speed and low-speed body at the same time, the average stress concentration over time is also high-speed body Showed a decreasing trend, while the concentration of the maximum shear stress was more significantly increased in the high-speed body when compared with the high-speed body alone. The significance of this study is to study stress concentration changes over time on the basis of stress concentration caused by non-uniformities, and to explore the mechanism of the gestation process of strong earthquakes.