THE EFFECT OF SAMPLE SIZE ON THE FLEXURAL STRENGTH OF SEDİMENTARY CARBONATE ROCKS UNDER CONCENTRATED LOAD

Abstract

Flexural strength is an important mechanical property used in the selection of the application area of natural building stones. The flexural strength of natural stones in our country is determined according to the test standards prepared by the European Union. According to TS EN 12372, the recommended test sample dimensions for the determination of the flexural strength of natural stones are 50×50×300 mm. However, generally, 20-30 mm thick plates are used in flooring, cladding, and exterior applications in buildings. In practice, 50 mm thick plates are rarely used, as well as preparing 50 mm thick test samples is a laborious and time-consuming process. In this study, it has been investigated how much the sample size affects the flexural strength of sedimentary carbonate rocks when using test samples prepared in two different sizes. It has been observed that the flexural strength values obtained from the test samples prepared in different sizes of the same rock are very close to each other. Besides, the stress distributions formed on the rock sample were analyzed with ANSYS Workbench 2020 R1. It has been determined that the stress distributions in the samples prepared in different sizes, exposed to the same load, occur in the same regions, and concentrate.

Keywords

• Natural Stone
• Flexural Strength
• Size Effect
• Standardization

References

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