This paper proposes a new critical concept for contact processing in the original two-dimensional discontinuous deformation analysis (DDA). A new critical concept that is inside or outside the reference line is proposed to enhance contact processing in the original DDA. When the vertex P is inside of one reference line, the reference line is shifted to the other edge so that P is now outside. The original rules are applicable only when both vertices are outside or inside of both the possible edges. The new critical concept is a stricter algorithm that remedies the indeterminacy of detecting the candidate reference line for vertex-to-vertex contact in the original DDA. The accuracy and effectiveness of the contact-improved DDA were studied using various numerical examples. The simulation results showed that the proposed method is more accurate and useful compared to original method after contact improvement and can be better applied to models with arbitrary vertex-to-vertex contact states.

本文为原始二维不连续变形分析（DDA）中的接触处理提出了一个新的关键概念。提出了参考线内部或外部的新关键概念，以增强原始DDA中的接触处理。当顶点P在一条参考线的内部时，参考线会移动到另一条边，因此P现在在外面。原始规则仅在两个顶点都在两个可能边的外部或内部时才适用。新的关键概念是一种更严格的算法，可纠正在原始DDA中检测到顶点到顶点接触的候选参考线的不确定性。使用各种数值示例研究了接触改进的DDA的准确性和有效性。仿真结果表明，所提出的方法在接触改善后比原始方法更加准确和有用，可以更好地应用于具有任意顶点到顶点接触状态的模型。