Cores were drilled from the panels made of different concrete mixtures. The compressive strength and splitting strength of core and cube specimens were tested at the ages of 7, 28, 60, 90, and 180 days. The effect of the diameter on concrete core splitting strength was examined. The strength correction factors were determined to convert the splitting strength of the core with diameter of 75 mm to that of the core with diameter of 100 mm. The regression analysis was carried out using experimental data to evaluate the core splitting strength as a function of the compressive strength of the concrete core. Then, the reliability of the proposed equation based on experimental data for compressive strength ranging from 20 to 80 MPa was assessed with the integral absolute error (IAE). Other existing relations between splitting strength and compressive strength of the cylinder were also evaluated with IAE, and most of the existing relations are not suitable for splitting strength of cores. The accurate power function relation formula is obtained with the test data. Only compressive test can be carried out by using drilling core samples in existing buildings, and the compressive strength and tensile strength of concrete can be obtained simultaneously, thus the numbers of splitting tests can be reduced and the mechanical property of existing buildings can be evaluated.

中文翻译：

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从钻芯抗压强度预测混凝土劈裂强度

核心是从由不同混凝土混合物制成的面板上钻出的。在 7 天、28 天、60 天、90 天和 180 天时测试了核心和立方体试样的抗压强度和劈裂强度。研究了直径对混凝土核心劈裂强度的影响。确定强度校正系数，将直径为 75 mm 的芯的劈裂强度转换为直径为 100 mm 的芯的劈裂强度。使用实验数据进行回归分析，以评估核心分裂强度与混凝土核心的抗压强度的关系。然后，使用积分绝对误差 (IAE) 评估了基于 20 至 80 MPa 抗压强度实验数据的所提出方程的可靠性。圆柱体劈裂强度与抗压强度之间存在的其他关系式也采用IAE进行评价，现有关系式大多不适用于芯体劈裂强度。利用测试数据得到准确的幂函数关系公式。在既有建筑中使用钻孔岩心样品只需进行抗压试验，即可同时获得混凝土的抗压强度和抗拉强度，从而减少劈裂试验次数，对既有建筑的力学性能进行评价。