中文摘要：

为了深入研究分形方法在接触理论中的应用，利用数值模拟实验研究了分形粗糙表面的接触机理，并首次提出了自仿射接触点的概念。该概念充分利用分形函数自仿射的优点，改善了传统分形接触理论中微凸体不满足分形特性的缺陷，去除了接触理论中微凸体相互作用无法考虑等假设。此外，将自仿射接触点应用于分形接触理论中，建立了新的接触模型，并进一步分析了分形维数及分形特征尺度对接触模型的影响。与经典的统计及分形接触模型的对比结果表明：利用自仿射接触点代替微凸体进行理论推导能更准确地揭示接触机理, 在相同的接触面积下，分形维数越大或分形特征尺度越小，接触压力越小。

英文摘要：

The numerical simulation for contact essence between fractal rough surfaces is conducted,and a concept of self-affine contact spot is introduced to propose a new fractal contact model.Compared with the asperity in classical fractal contact model,the self-affine contact spot better describes the process of fractal contact.The self-affine contact spot now gets fractal,and the assumption of no interaction between asperities is unnecessary.Under the assumption that the rough surfaces are all unlubricated isotropic surfaces,this model can be simulated by W-M function.Making use of the relationship between the maximum deformation and contact area of contact spot,the classical fractal contact model is modified to further approach the engineering practice.It is found that G-W model ignores plastic deformation of contact spot thus to underestimate the contact load of rough surfaces;M-B model leads to a smaller maximum deformation to difficultly use size-distribution function and overestimates the contact load.The self-affine contact spot instead of asperity enables to accurately evaluate the contact pressure,The more the fractal dimension（or the less the fractal characteristic scale）,the less the contact pressure is needed for same contact area.