The strength of the Brazilian fracture test
The strength of the Brazilian fracture test
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DOI：
10.1016/j.jmps.2023.105473
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发表时间：
2023-10-29
影响因子：
5.3
通讯作者：
Lopez-Pamies, Oscar
中科院分区：
文献类型：
--
作者：
Kumar, Aditya;Liu, Yangyuanchen;Lopez-Pamies, Oscar
自20世纪40年代引入至今，所谓的巴西测试已被全世界的从业者所接受，作为间接测量混凝土，岩石和其他抗压强度相对于抗拉强度较大的材料的抗拉强度的首选方法。这是因为该试验在试样的制备（圆盘）和载荷的施加（两个压板在它们之间压缩试样）方面都很容易。然而，这一实际优势必须得到调和的事实，从巴西测试的观察-是一个间接的实验，在这个意义上，它涉及的不是均匀的单轴拉伸，但不均匀的三轴应力状态在整个标本-必须适当地解释是有用的。本文的主要目的是进行一个完整的定量分析，在哪里和何时裂缝成核和传播的巴西测试，从而建立如何适当地解释其结果。我们通过部署Kumar等人的相场断裂理论来做到这一点。（2020），该理论最近被建立为完整的断裂理论，能够准确描述任意准静态加载条件下线弹性脆性材料中裂纹的成核和扩展。本文的最后一部分提出了一个新的协议来推断材料的拉伸强度从巴西测试，改进了目前的ISRM和ASTM标准。
Since its introduction in the 1940s until present times, the so-called Brazilian test has been embraced by practitioners worldwide as a method of choice to indirectly measure the tensile strength of concrete, rocks, and other materials with a large compressive strength relative to their tensile strength. This is because of the ease that the test affords in both the preparation of the specimen (a circular disk) and the application of the loads (two platens compressing the specimen between them). Yet, this practical advantage has to be tempered by the fact that the observations from a Brazilian test - being an indirect experiment in the sense that it involves not uniform uniaxial tension but non-uniform triaxial stress states throughout the specimen - have to be appropriately interpreted to be useful. The main objective of this paper is to carry out a complete quantitative analysis of where and when fracture nucleates and propagates in a Brazilian test and thereby establish how to appropriately interpret its results. We do so by deploying the phase-field fracture theory of Kumar et al. (2020), which has been recently established as a complete theory of fracture capable of accurately describing the nucleation and propagation of cracks in linear elastic brittle materials under arbitrary quasistatic loading conditions. The last section of this paper puts forth a new protocol to deduce the tensile strength of a material from a Brazilian test that improves on the current ISRM and ASTM standards.