非连续变形分析方法中人为参数的影响

非连续变形分析方法(DDA) 自创立以来，已在分析不连续体的大变形、大位移的问题中显示了其优越性。但DDA方法需要人为设置一些控制参数，通过一个简单的滑块模型，分别采用不同的时步大小、不同的接触弹簧刚度、并比较相对误差，分析了人为设定的参数对DDA计算结果的影响，指出仅在合理的取值范围内，大时步和大的接触弹簧刚度才能产生较好的计算结果；同时对造成这种影响的原因做了一定的探讨，并建议了参数取值的上下限原则。

Influences of artificial parameters in DDA method

Since the discontinuous deformation analysis method(DDA) has been developed,more and more advantages are being displayed in simulating large displacement and deformation of the system of discrete bodies.In this method,however,some artificial parameters have to be preset,which more or less affect the results.By means of a simple model involving only one slide body,the effects of those artificial parameters such as the step length and the stiffness of contact springs on the results are analyzed.It is pointed out that only in the proper ranges the larger time steps and larger stiffness can give rise to better computational results.Some reasons of leading to theses results ate discussed.The lower bounds and the upper bounds for the artificial parameters are suggested.