Гравіметричні роботи на території Дністровської ГАЕС

Abstract

The purpose of this work is to perform gravimetric measurements at the points of the existing reference geodetic network on the territory of the Dniester hydro-accumulating power station (DHAPS) to study the magnitude of the correction in the leveling for the non-parallelism of the level surfaces. Method. For performance of gravimetric works on the territory of the DHAPS we used three high-precision gravimeters GNU-KV. Before starting the measurements we conducted a number of studies of these gravimeters: adjusting the optical system, adjusting the device to a minimum of tilt sensitivity, detecting and controlling the sensitivity, determining the timing of the reference, determining the temperature characteristics, benchmarking, calculating the range of measurements and its adjustment, determining the displacement of the zero point and its inclusion. One of the most important studies is the standardization (definition of a constant) of gravimeter. Standardization of gravimeters GNU-KV was carried out at the points of the Kiev narrow-band gravimetric polygon. The distance between them is about 10 km. Between these points, with sufficient accuracy, the value of acceleration in free air 5g is known For correction of leveling 7 gravimetric works were performed that covered 10 points of the well-known geodesic network at the DHAPS. At the reference point, the value of acceleration of free fall g was calculated using the global model of the gravitational field of the Earth EGM2008 to 2190 degree/order. Results. Based on the measured data, the difference between free fall acceleration for each work is calculated respectively. After working out gravimetric data it was established that the correction in leveling for the nonparallel level surfaces varies from 0.089 mm to 1.517 mm. For some lines of the network, the correction for the nonparallelism of level surfaces exceeds the permissible systematic error of leveling the first class twice. Accordingly, when working out the leveling of the first class on such lines it is necessary to take into account this correction. Failure to take into account this correction will result in an increase in the systematic error of leveling in proportion to the length of the leveling process, which will result in false results about the height and displacement of the geodetic points. The scientific novelty and practical significance. For the first time in the territory of the Dniester HAPS gravimetric surveying was carried out to calculate corrections in precision leveling for the non-parallelism of level surfaces. The necessity to carry out such removal on the territory of the DHAPS is grounded in order to reduce the systematic error of leveling.