节理的表面形貌对其法向闭合变形有重要影响,对给定的节理而言,接触状态也是影响闭合变形的重要因素,不同接触状态得出的闭合变形曲线差异较大.基于Hertz理论的Greenwood模型不能考虑接触状态对闭合变形的影响,Brown模型引入不同接触状态节理的组合形貌拓展了Greenwood模型.对单个微凸体的弹性分析表明:Greenwood模型与Brown模型均没有考虑基体变形的影响,基于统计理论将考虑基体变形的单微凸体变形模型应用于整个粗糙节理表面得到一个新的节理闭合模型.最后,采用该模型分析处于不同接触状态的节理闭合变形数据并与Brown模型的计算结果进行比较,验证该模型的合理性.%Joint surface topography has important effect on its closure deformation behavior. For a given joint, the contact state is also a key factor and different contact states will get curves with big difference in joint closure test. Greenwood model based on Hertz theory is a commonly used model but it is difficult to consider the contact state of joint surface. An improved version of original Greenwood model was addressed and this model introduce composite topography, whose height at any point is the sum of the height of the upper and lower joint surfaces measured form arbitrary reference planes. Elasticity analysis showed that the asperity contacts can cause compression of the asperities and the deformation of the substrate. Greenwood model and the Brown model do not consider the asperity and substrate deformation. A single asperity mechanical model extended to the whole rough surface based on statistical theory. Then, a new improved version of Brown model with inclusion of compression of the asperities and the deformation of the substrate is formulated. At last, comparison between this improved Brown model and original Brown model is conducted to analyze joint closure deformation data from different contact states of joint with the same topography; and the rationality of the improved Brown model is verified.
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