Determination of the basic friction angle on undeteriorated and deteriorated surfaces in different rocks

In this thesis, Tilt tests were carried out to determine the basic friction angle (b) of the undeteriorated and deteriorated samples after the accelerated weathering tests. These tests were performed on saw-cut flat surfaces, in dry, saturated-wet and saturated-submerged conditions and on prismatic samples with two different shapes. The results of the basic friction angles were compared with the physical, mechanical and chemical values of the rocks used in this study. As a result of these tests, it was determined that the use of 7x7x3.5cm (short) samples rather than 7x7x7cm (long) samples would be more appropriate. In general, it was determined that the basic friction angle of the shorter samples increased with deterioration, also the basic friction angle of the saturated samples was higher than the dry samples due to weight, and the basic friction angle was higher than expected due to the adhesion force in wet and submerged conditions. As a result; it was determined that the sample shape, the wetness on surface and the degree of deterioration are effective in determining the basic friction angle. In the laboratory tests, it is recommended to use short and dry samples to determine the basic friction angle.