PECULIARITIES OF ESTATE OF THE NATIONAL GEODESIC NETWORK IN THE CENTRAL REGION OF UKRAINE

A common feature of NGN in the central region of Ukraine is aging. The differences are determined by the peculiarities of fixing its points on the locallity place. The choice of a specific type of geodetic signal was determined by local physical and geographical features of the location of the point, such as: soil properties, depth of soil freezing, visibility conditions, etc. On the territory of Poltava and Kirovohrad regions there are 70 types of centers, benchmarks and brands, which are fixed points of the planimetric, altitude and gravimetric networks. At the same time, only 9 types significantly prevail of distribution: soil centers and benchmarks for areas with shallow (up to 1.5 m) seasonal soil freezing of types 1, 1op, 2, 2op, 146, 160 and 160 Late; wall benchmarks type 143 and wall beacons type 144.The peculiarity of the central region of Ukraine is the presence of points that are both points of the planimetric NGN 1, 2 and 3 classes, and altitude NGN I or II classes. Thus such points are fixed either by the ground centers, or ground benchmarks, or horizontal beacons.Because of the lack of geodetic information on a significant part of the points of the planned and altitude networks, the condition of the NGN of the central region of Ukraine cannot be considered satisfactory at present. For the requirements of monitoring, it is proposed to expand the content of maps of construction, survey and updating of geodetic points with data on the rights of ownership or use of land locations of points and their cadastral numbers. It is also necessary to update the data on those points in the central region of Ukraine, the inspection of which was realized before 2010.The indicator of admissibility of losses of points of NGN which should be defined separately for networks of 1, 2 and 3 classes is offered. If according to the results of the calculation the actual amount of points is less than the minimum allowable for the corresponding class, and the indicator of admissibility of losses of points has a minus sign, then the corresponding network does not meet the technical parameters. Loss of points in this case is not allowed, and lost points must be restored.The results of the calculation of this indicator for the central region of Ukraine indicate the need to restore 6 points of the planimetric network of the 2 class in the Kirovohrad region and the inadmissibility of further losses of points of this class.