In this master's thesis we examined the change in the geometry of a flexible pipe using terrestrial laser scanning point cloud data. Firstly, we carried out measurements in the pipe and the backfill above the pipe using the terrestrial laser scanner. Those measurements were the basis for making the registered point cloud. We made the software for the purpose of verifying the change in the geometry of the pipe from the point cloud data. The dimension of the pipe was determined by fitting an ellipse to the point cloud data using the method of least-squares. The fitted ellipse represented the parameters of the diameter of the pipe in the vertical and horizontal directions. The results of the diameter of the pipe were then analysed on the examples of a pipe that is not installed and is placed freely on the ground and two built-in pipes. The first example of a built-in pipe is a pipe that is backfilled with soil and the second one is a pipe that is sealed under concrete and then backfilled with soil. From the point cloud data representing the backfill soil above the pipe we obtained the data about the height of the backfill. This enabled us to analyse the impact the height of the backfill has on the deformation the pipe geometry. In addition to measuring with a terrestrial laser scanner, we measured the diameter in the horizontal and vertical directions at the beginning, middle and end of each section of the pipes using a handheld laser meter. Different measuring methods were used to determine the differences between pipe diameter measuring methods. This master’s thesis is a detailed examination and evaluation of the use of a terrestrial laser scanner for the purpose of determining the change in pipe geometry.
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