Renmin Zhujiang (Jan 2025)
Estimation of Uniaxial Compressive Strength and Tensile Strength of Sandstone Based on Point Load
Abstract
In rock mechanics and engineering practice, accurate and rapid evaluation of uniaxial compressive strength and tensile strength of rock is important for engineering design and construction safety. Traditional test methods are time-consuming and laborious, and the method of determining uniaxial compressive strength and tensile strength of rock by point load strength index is simple and fast. In this paper, the point load test, uniaxial compressive test, and Brazilian splitting test under dry conditions were carried out based on 11 different types of sandstone, and the relationship of the point load strength with compressive strength and tensile strength was established by different fitting methods. The results show that the point load strength of sandstone has a significant correlation with compressive strength and tensile strength, and the variation coefficients of the two point load strengths have little difference, which can be used as the index for calculating the point load strength. Three different types of transformation relationships can be used to fit the point load and uniaxial compressive strength, including non-0 intercept linear relationship, 0 intercept linear relationship, and power function. The linear fitting method is simple to calculate, and the correlation coefficient of linear fitting with 0 intercept is higher than that of linear fitting with non-0 intercept. Both the power function fitting formula and the 0 intercept fitting formula can be used to estimate the uniaxial compressive strength in practical engineering. For the relationship between point load strength and tensile strength, it is also advantageous to use the 0 intercept linear formula for estimation.
