Weathering induced Brazilian Tensile Strength and fracture characteristics of sandstone and their prevailing mutual association

This paper evaluates the variation and relationship of Brazilian tensile strength and fracture characteristics of sandstone under different weathering grades. Brazilian tensile strength experiments were performed on Fresh and slightly weathered sandstone specimens using an automated compression measuring machine UTC-5431. Image-based fracture characterization was carried out using public domain open-source software ImageJ. Furthermore, SPSS and Microsoft Excel were used to analyze the relationship between Brazilian tensile strength and fracture characteristics. Results demonstrate that sandstone tensile strength decreases as fracture maximum deviation distance (FMDD), fracture deviation area (FDA) and fracture length (FL), and weathering grades increase. Additionally, FMDD, FDA, and FL increase with an increase in weathering grade. The correlation results revealed that the tensile strength of fresh sandstone has a strong relationship with FMDD, FDA, and FL. Whereas, in the case of slightly weathered sandstone, BTS has a strong correlation with FMDD and FDA. Whereas multiple regression analysis shows that BTS has a strong relationship with fracture characteristics. Therefore, estimating the fracture characteristics of sandstone using its tensile strength is convenient, however, the sensitivity of sandstone strength properties and fracture characteristics to weathering must be acknowledged.