GEODETIC SUPPLY FOR THE CONSTRUCTION OF ENGINEERING STRUCTURES
Authors: Kovalenko L. 
Published: August 2022

The construction of engineering structures when transferring the project to the area is impossible without geodetic work. The composition and sequence of engineering and geodetic works depend on the features of the design and construction of facilities and the type of structure. The purpose of the article is to consider geodetic works in the construction of engineering structures. The issues of performing engineering and geodetic works during the construction of structural elements of the bridge are considered. During the construction process, it is necessary to ensure full compliance with the design documentation and high accuracy of work performance. These requirements can be achieved by using high-precision geodetic works with constant monitoring of the installation work.
At all stages of the bridge construction, geodetic works accompany the transfer to the terrain of the bridge axis, the resistance axis, perform a detailed breakdown during the construction of resistances and the installation of purlins. Also, the construction of individual parts of the building is constantly monitored, the dimensions and shape of the mounting elements are checked.
When building large structures, it is necessary to have information about the points of the geodetic base of the bridge crossing, an extract from the catalog of coordinates and elevations of the geodetic base. The breakdown is carried out by tying to the points of the geodetic reference network, which has coordinates in the absolute or conditional system.
Modern construction requires the use of new technologies and methods for performing geodetic work related to the introduction of electronic devices and programs for automated information processing into geodetic practice. Currently, a large number of geodetic instruments and new technologies in geodesy have been created, which differ from traditional ones.
To carry out survey work, geodetic instruments, such as electronic total station and levels, were used. The electronic total station measures distances, angles and processes data directly in the process of field work, has an internal memory where it can store all the data obtained as a result of measurements.
The digital level has a device for automatic registration of measurements along the rail and a processor for subsequent processing of all leveling results. During measurements, the device measures the distance to the rail and the elevation between points. This eliminates two main types of errors: observation errors when taking a reading and error in distance measurements.
During the construction of supports, a temporary rapper is installed on each of them, which is tied to permanent rappers by leveling moves.
The removal of marks on the supports is carried out by methods of geometric or trigonometric leveling. The coordinates of the rappers were received and entered into the local plan. Marks for serifs of the device with a retroreflective effect were pasted on the bridge supports. The data of coordinates and heights were entered into the total station memory.
Geodetic work carried out during the construction of the span structure ensures the accuracy of its assembly in accordance with the project. After the installation is completed, the assembly results and deviations from the project are monitored.
The construction of structural elements of engineering structures must comply with building codes and geometric parameters of the facility design.