Abstract The properties of socket wall significantly affect the loading capacity of a rock socketed pile, and the shear mobilization relies heavily on the roughness of the socket surface and the boundary condition in reality. In this study, laboratory tests have been conducted to investigate the performance of concrete-rock interface shear under constant normal stiffness (CNS) condition and, in particular, an alternative profile to characterize the interface roughness is assembled as series of similar triangular asperities. The profiles of rock samples differing in the dimension of asperities have been divided into five categories (including one kind of regular triangular asperities for comparison). Direct shear tests on the samples are carried out under CNS conditions, with different initial normal loads and normal stiffnesses. The observations indicate that the shear behavior of concrete-rock interface is highly dependent on the uniformity of asperity geometry; compared with the roughness of similar triangular asperities, the one of regular asperities behaves more brittleness and shows a higher peak strength as well as a lower residual strength. In addition to the general tendency, it is found that the local lift-off of some asperities is pronounced relied heavily on their heights, and the redistribution of local stresses can further affect the global shear behavior. The size-dependent sequence of asperity failure can be also observed, confirming the earlier theoretical anticipation reported by the authors. Careful observations during this testing made it possible to develop a micromechanics-based model published elsewhere, and the comparison between them are presented.

中文翻译：

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朝向包含相似三角形凹凸的混凝土-岩石界面剪切

摘要 承插墙的特性对嵌岩桩的承载能力有显着影响，而实际中承插面的粗糙度和边界条件的剪切动员在很大程度上依赖于承插面的粗糙度和边界条件。在这项研究中，已经进行了实验室测试以研究在恒定法向刚度 (CNS) 条件下混凝土-岩石界面剪切的性能，特别是将表征界面粗糙度的替代轮廓组装为一系列类似的三角形凹凸不平。将不同凹凸尺寸的岩样剖面分为五类（包括一种正三角形凹凸不平作为对比）。样品的直剪试验在 CNS 条件下进行，具有不同的初始法向载荷和法向刚度。观察结果表明，混凝土-岩石界面的剪切行为高度依赖于粗糙几何形状的均匀性；与相似三角形凹凸的粗糙度相比，规则凹凸之一的脆性更大，峰值强度更高，残余强度更低。除了总体趋势外，还发现一些凹凸不平的局部抬升严重依赖于它们的高度，并且局部应力的重新分布会进一步影响整体剪切行为。还可以观察到与尺寸相关的粗糙失效序列，证实了作者报告的早期理论预期。在此测试期间仔细观察使开发在别处发表的基于微力学的模型成为可能，并提供了它们之间的比较。