PHOTOGRAMMETRY USİNG UNMANNED AİR VEHİCLE
Retaining wall deflection was monitored by capturing images using a drone. Images were further analyzed using photogrammetric software to develop a quick alternative methodology to monitor structure deflection. In carrying out the study, monitoring using a commercial UAV, in combination with point cloud formation, georeferencing, and comparison software (cloud compare), is performed. Results showed good agreement with the traditional inclinometer deflection measurements and numerical analysis, thereby demonstrating the feasibility of the proposed method. Furthermore, the methodology’s advantage over other monitoring techniques in terms of speed, lower cost, and ease of use was established.
EFFECT OF CYCLİC SHEARİNG ON CONTACT SURFACES
Direct shear tests under constant normal force were conducted on sandpaper to quantify the cyclic effect on nonconforming contact surfaces. Tests were conducted at three different normal loads on sandpaper for 10 and 20 cycles. The results showed passivation of the shear strength where a constant value of friction coefficient was reached after around 15 to 17 cycles for all tests, except for tests conducted at the lowest vertical force. The broken-off mass weighed during the 10th and 20th cycles seemed to show a linear relationship with the vertical force and with the particle analysis, determined via microscopy.