中文摘要：

岩石的抗拉强度是导致岩石黏结性破坏的极限应力，在工程上，将劈裂法试验规定为测定岩石抗拉强度的必做试验。大量的试验结果研究表明：劈裂法不能真实地反映岩石的抗拉强度，实验结果有误差。本文经过硬岩的巴西劈裂法实验，得到了硬岩巴西法试验结果的误差值与厚径比的关系曲线，可以知道误差影响的主要来源是试件的厚度变化误差。由计算结果和回归曲线还可以知道，在厚径比为1．0附近时，误差影响量总和最小。因此，为了控制实验误差，建议以后进行劈裂试验时，试件厚径比L／D严格取1．0。

英文摘要：

The tensile strength of rock is the ultimate stress of the rock cementation during its destruction. Brazilian test should be done to determine the tensile strength of rock. However, various tests have indicated that, Brazilian test can not exactly reflect the tensile strength of rock, and there are some errors in the test results. Through Brazilian test of hard rock, the relation ship between the error and the thick diameter ratio was obtained. Moreover, the major influence on error came from the variation of the thickness of test samples. The error was the smallest when the thickness-diameter ratio （L/D） was close to 1.0. Therefore, It was suggested that ther L/D ratio of test samples should be 1.0 strictly.