有限元分析中断裂区域单元的划分

根据弹性理论的叠加原理，研究了有限元分析中的单元划分问题。通过有限元结点位移反演边界力系数与理论边界力系数进行比较来判别断裂区单元划分是否合理，应用模拟数据定量分析了二维和三维有限元法的单元划分，为有限元法在地学研究中的实际应用提供参考依据。

PRINCIPLE OF IMPROVEMENT ON THE SEISMIC LOCATION PRECISION WITH THE IMAGE STATION

It is not easy to get a satisfactory result for the seismic location which is far from the seismic net. The Image Location Method (ILM) can improve the seismic location precision effectively. In this paper, the character of coefficient of location equations based on ILM is analysed under the homogeneous crust model, and two conclusions are obtained as follows: (1) the ILM makes the location equations add the reduced equations, and the number of image stations are related to the known condition and the evaluating parameters, and theoretically when they exceed the number of independent reduced equations, the location precision will not be improved practically. (2) considering that the distribution of seismic net and the quality of data from different station are distinct, and that the action of imaging the different station on improving the location accuracy is distinct too, the optimum image station should be selected, and a method of whick is found in the paper.