Direct shear tests on samples containing similar triangular asperities have been carried out under constant normal stiffness (CNS) conditions, and observations demonstrated that there exists local lift-off of shallower asperities across the interface, resulting in a redistribution of local stresses and further impacting the global shear behavior. This study further modifies the existing theoretical model based on multiple-asperity configurations, previously presented by the authors. The proposed method relates the normal and shear stresses on the individual asperity to interface strength and corresponding displacement in terms of the asperity inclination and contact areas. The emphasis is on quantifying the number of shallower asperities that would be lifted off when the closely contacted asperities are dislocated by an amount of interface dilation. In addition to the mechanism of local lift-off itself, the resultant redistribution of global shear stress on remaining asperities can be also taken into account. The proposed model is verified by predicting experimental observations published elsewhere, and the comparison appears to be satisfactory.

在恒定法向刚度下对含有类似三角形粗糙度的样品进行了直接剪切试验（CNS）条件和观察表明，界面上存在较浅凹凸体的局部升空，导致局部应力的重新分布并进一步影响全局剪切行为。本研究进一步修改了作者先前提出的基于多重粗糙结构的现有理论模型。所提出的方法将单个粗糙体上的法向应力和剪切应力与界面强度和在粗糙度倾斜和接触面积方面的相应位移联系起来。重点是量化当紧密接触的凹凸体因一定量的界面膨胀而错位时将被剥离的较浅凹凸体的数量。除了局部升空本身的机制外，还可以考虑由此产生的对剩余凹凸体的整体剪切应力的重新分布。所提出的模型通过预测在其他地方发表的实验观察得到验证，并且比较似乎令人满意。