Determining Roughness Angle of Limestone Using Optical Laser Scanner

In this study, a limestone rock core specimen with 6.94 cm x 4.95 cm dimensions was exposed to tensile force by Brazilian test and rough surfaces were obtained. Following the Brazilian test, roughness angles were measured by a laser scanner along one side of the rock specimen. For this purpose, Nextengine 3D Desktop scanner was used. The 17 profiles were studied along the width of the core with a 0.3 mm interval. Approximately 10000 points produced for each profile, some of them are in the “+” and some are in the “-” direction along each profile. Maximum and minimum roughness angles are calculated as 65.580 and 1.56x10-5 degree respectively. The average roughness angle value of the profiles is 13.870. The percentage of the roughness angle between 13 and 14 degrees were 2.65% and 2.70% for “-” and “+” directions on the rock surface, respectively. Mathematical analyses of 17 profiles showed that roughness profiles can be expressed by 21st – 30th degree polynomial equations with approximately 10-4 degree standard deviation.