Determination of vertical deformations in Obruk Dam by precision Nivelman Method

The geometric shape changes that occur in the earth's crust or in large structures are called 'deformation'. Deformations are seen as vertical and horizontal position changes. The movements of the ground wall in the vertical direction are generally determined using the precision leveling method. To implement this method, a network is constructed that includes the deformation zone and its surroundings. The network consists of points, object points and fixed points. The object points are selected from places where deformation is expected to cover the region subject to the deformation study. The fixed points are located where the deformation is close to the region to be investigated but where no deformation is expected, where measurements can be made. After the network is set up for deformation measurements, precise leveling measurements are made to determine the heights of the deformation points. The results of the measurements made at specific time intervals are investigated by the Precise Leveling method. As it is aimed to determine very small movements, all the conditions of precision leveling must be met while making measurements. The data obtained in the measurements are mismatched and the mismatched measures are determined and canceled before balancing. The heights of the deformation points are determined by using the free mesh stabilization method according to the measured least squares method. This study was carried out in order to determine the possible vertical deformations that could occur in the vicinity of the Obruk Dam and its surroundings. In order to determine the vertical deformations in the Obruk Dam body, the RS point is made of bronze in the concrete concrete grounds, which are manufactured at 8 reference points and 6 dam constructions. In addition to this, 44 pieces of object points on the dam body have been manufactured as a leveled aparate. In total, 58 points were precisely leveled using electronic nova and invar mirrors with a measuring accuracy of 0.6 mm / km. Although there are no horizontal coordinates of 6 RS points, these points are only used for relative height measurements. A total of four campaign measurements were made under the project. The length of the leveling line measured in round trip is about 22 km. The standard deviation value for the 1 km round-trip measure from the difference between the return and return measures and the loop closure was calculated. An error limit of 4S is used in the evaluation. The DEFANA module of the PANDA deformation analysis program was used for evaluation of the measurements made and deformation analysis. In this study, the evaluation of one dimensional measurement of PANDA program, deformation analysis and results obtained without working as 4 campaigns are explained in detail. Deformation analysis was carried out in six periods of four campaigns. Movement between +2 mm and +5 mm was observed at object points above the water level when deformation analysis was performed with campaign measures 1 and 4. The dam water level between the first and fourth campaigns was 1.76 m. With the increase in water level, the increase in pressure on the body is thought to bring about the movements at object points. Apart from this, in the deformation analyzes made at the object points, no motion was observed.