ANALYSIS AND GENERALIZATION OF REGULATORY SUPPORT FOR GEODESIC SUPPORT OF ROAD CONSTRUCTION OBJECTS

The transfer of the project to the site requires the performance of measurements and constructions with high accuracy. Changes in the technology of geodetic works related to the computerization of geodesy, the introduction into geodetic practice of electronic geodetic instruments and automated processing programs, require the introduction into production of both traditional methods of geodetic measurements and new technologies and methods of geodetic works. Despite the fact that geodetic works are an integral part of construction, in the regulations on surveys, design and construction of roads and man-made structures quite limited regulation of the content of work on the transfer of projects to the field, division work, executive surveys, geodetic quality control, accuracy requirements, etc. Given the current state of regulatory and legal support for geodetic support of road construction sites, it is advisable to develop a national standard for the implementation of geodetic surveying and geodetic control in the construction of road construction sites. This standard will supplement the main provisions of regulations on the construction of roads and transport facilities. With the growing volume of design, construction and overhaul of roads, it is necessary to standardize all stages of design and construction work, including those related to geodetic production. The development of technologies and methods of geodetic works related to the computerization of geodesy requires the introduction into production of both traditional methods of geodetic measurements and new technologies and methods of geodetic works. Based on the analysis and generalization of regulatory support for geodetic support of design and construction of roads and artificial structures, the need to develop a national standard for geodetic surveying and geodetic control in the construction of road construction as a supplement to the basic provisions of regulations on road construction and transport facilities.

Analysis of technological schemes for creating a geodetic control at the industrial site

The article highlights the issues of creating with the necessary accuracy a planned control on the industrial site of the engineering structures under construction using satellite technologies and total stations. Depending on the design features of the engineering structures under construction, as well as the technological scheme for the installation of building constructions and industrial equipment, various schemes for creating such control are considered, based on the application of the inverse linear-angular notch. Errors in the source data are one of the main errors that affect the accuracy of geodetic constructions, including the solution of the inverse linear-angular notch. When creating a geodetic network in several stages, the errors of the initial data of the first stage affect the values of the root-mean-square errors (RMS) of determining the position of the second stage points, the errors of which affect the value of the RMS of the position of the third stage points, etc. The reason for their occurrence is the errors of geodetic measurements that occur at each stage of control creating, as well as the stability violation of the points during the production of excavation, construction and installation works. When determining the coordinates of a separate project point at the stage of its removal in-situ by a total station, the entire network is not equalized in the vast majority of cases, and the coordinates of the starting points to which the total station is oriented are considered error-free. As a result, the RMS determination of the points coordinates of the control network or the removal of the design points of the elements of building structures and equipment will also be considered satisfying the requirements, i.e. the measurement accuracy will be artificially overestimated and will not correspond to the actual one obtained. This is due to the fact that the accumulation of errors in the initial data is not taken into account when the number of steps (stages) of control creating increases. The purpose of this work is to analyze the influence of measurement errors and initial data when creating a geodetic control on an industrial site by several stages of its construction based on inverse linear-angular notches and a priori estimation of the accuracy of the determined points position.

Geodetic monitoring of deformations of engineering structures

Unfortunately, all kinds of anthropogenic and natural factors contribute to the deformation of man-made structures. Geodetic control of buildings and structures, timely detection and elimination of deformations is a guarantee of long-term operation of the building. Monitoring is one of the most important tools to ensure the reliability and safety of multi-storey and large-scale buildings and structures during construction and operation. A significant amount of instrumental control during construction and operation is carried out by geodetic methods. Geodetic methods are used to determine both local and general deformations of buildings and structures, deviations of load-bearing, fencing structures from vertical and design drawings, foundations and soil settlements, through which the technical condition of the building or structure is specially assessed. Today, the analysis of deformations is an important task for every region of our country, especially for areas with changes in the earth's surface. The field of deformation research in the Republic of Kazakhstan is quite developed and there are many necessary materials to identify such changes. In our country, special services are organized to control any benchmarks and analyze the results of high-precision measurements in several cycles to detect any changes on the earth's surface. Therefore, this article provides an overview of both the classical methods of geodetic control and the tools and technologies used to determine the quantitative characteristics of the deformation of engineering objects.

Gauss-Markov model with random parameters to adjust results of surveys of geodetic control networks

Alignment of an engineering object project in the field is always conducted at the points of the geodetic control network, the coordinates of which are determined on the basis of the results of its elements survey and with connection to the national spatial reference system. The points of the national spatial reference system determined on the basis of previous surveys have specified coordinates with adequate accuracy, which is included in their covariance matrix. The coordinates of the geodetic control network points are determined more accurately than the points of the national spatial reference system and this means that the results of surveys of the geodetic control network have to be adequately incorporated into the coordinates of the reference points. In order to perform this incorporation, it may be assumed that the coordinates of the reference points are random, that is, they have a covariance matrix, which should be used in the process of adjusting the results of the geodetic control network observation. This research paper presents the principles for the estimation of the Gauss-Markov model parameters applied in case of those geodetic control networks in which the coordinates of the reference points have random character. On the basis of the observation equations δ + AX = L for the geodetic control network and using the weighting matrix P and the matrix of conditional covariances (P −1 + AC X A T ) for the observation vector L, the parameter vector X is estimated in the form of the derived formula X ^ = ( C X − 1 + A T PA ) − 1 A T P ⋅ L {\bf{\hat X}} = {\left( {{\bf{C}}_X^{ - 1} + {{\bf{A}}^T}{\bf{PA}}} \right)^{ - 1}}{{\bf{A}}^T}{\bf{P}} \cdot {\bf{L}} . The verification of these estimation principles has been illustrated by the example of a fragment of a levelling geodetic control network consisting of three geodetic control points and two reference points of the national spatial reference system. The novel feature of the proposed solution is the application of covariance matrices of the reference point coordinates to adjust the results of the survey of geodetic control networks and to determine limit standard deviations for the estimated coordinates of geodetic control network points.

Design and Geodetic Adjustment of Levelling Network for Establishment of Unified Control Points in Korea

The unified control points (UCPs), the multi-dimensional geodetic reference points installed in the low elevated area, has been established in Korea for the combination of the horizontal and the vertical geodetic control. While the 1st-phase UCPs network was completed in 2011 with a spatial density of about 10km, its densification has been underway as the 2nd-phase project. The UCPs supersedes the legacy geodetic points, such as triangulation points and benchmarks (BMs) once the 2nd-phase implementation. Although the horizontal network of the UPCs can be readily realised by GNSS technology, a technical challenge of the vertical component remains to be settled due to characteristics of the geodetic levelling technique. To this end, a pilot study was conducted to design a new version of the UCPs-based levelling network and to demonstrate its effectiveness with a comparison of the legacy. In this paper, a concept of the UCPs-based levelling network is briefly addressed with some prominent examples, and details of a pilot network and its measurements is given with the network adjustment procedure. Finally, results of the adjustments are provided with an emphasis on the influence of the newly designed network in terms of accuracy, reliability and estimated heights.

Establishment of geodetic control network for Quy Nhon University area

Geodetic control network of Quy Nhon University (QNU) is established based on GNSS technology and electronic total station technology in combination with the middle geometrical elevation surveying method, bench mark of network built with firm concrete installed with a centralized insulator cap. The network consists of 11 points, of which 2 points are traversed from the cadastral point of class I, used as the starting points for the traverse. The network is built based on total station method with 2 turns of forward and backward surveying. The network’s leveling height is measured by the middle geometrical elevation surveying method, ensuring compliance with the procedures and rules of the Ministry of Natural Resources and Environment. The research result includes a system of stable and solid network points, together with the coordinates and the leveling height that are closely adjusted by specialized software, control network diagram. Geodetic control network of the QNU is important in setting up map, general plan, planning, construction and serving for teaching and scientific research of the university.

The need for geodetic control to monitor the displacements of buildings and structures

The article overviews the main reasons of settlings and other deformations of constructed and operated buildings and structures. The authors consider geodetic control methods of the deformations using various examples. Some recommendations on their monitoring are given. The deformations are often take place bесause of unsatisfactory engineering surveys. Therefore, these problems are urgent not only for designers and builders but also for engineering surveyors.

A WEB-BASED GIS PORTAL FOR SIMULATING GEODETIC CONTROL NETWORKS IN REPUBLIC OF KENYA

Geodetic networks development begun in Kenya and Africa as a whole at the dawn of 20th century. Consequently, enormous geodetic data has been realized. In Kenya, the data was recorded in form of paper trigonometric cards, paper topographic maps, and paper cadastral map sheets and centrally archived in the ministry of lands and physical planning headquarters in Nairobi. This was to assist locate and visualize suitable survey of Kenya geodetic pillar of interest to user. However, the user still has to commute to the headquarters in order to physically acquire coordinate information of any pillar in the country. This circumstance has fabricated a framework that has triggered accumulation of millions of paper records. The effectiveness and efficiency of serving the users is greatly undermined by the manual process. Therefore, an alternative solution is necessary to alleviate dependence on an outdated manual process. As a result, this study sought to fill this gap by designing a web geoportal for management of geodetic control networks and user access which incorporates making of payments of coordinates in different systems remotely. The geoportal comprises of an integration of a database management system, a server configuration and a website with an automated data access through a payment gateway. Java scripts and python programming languages were used. The final platform has the following capabilities: spatial visualization, co-ordinates system conversion, online payment, and request and access of data remotely. We foresee that the system will aid the ministry of lands and physical planning to disseminate geodetic information to users efficiently and effectively while tracking revenue payments.

Mathematical modeling in the problems of the geodesic control of the stressed-formated state of the gas pipelines at above-ground parts

Geodetic methods of monitoring the stress-strain state of gas pipelines in the areas of overhead pipeline crossing involve obtaining discrete data on the deformation of its axis in the form of a set of three coordinates (x, y, z). For their elaboration a mathematical model of the experimental-theoretical method of geodetic control of gas pipelines’ SSS is proposed. The simulation process was performed on the basis of geodetic discrete data, based on which, using the Lagrange interpolation polynomial, the equation of the line of bending of the axis of the gas pipeline was obtained, which allowed to pass further to the bending moments along the entire span. The accuracy of the proposed method has been estimated, which showed that the obtained bending moment diagrams reflect the SSS of gas pipelines with an accuracy of 1.5% in the central part of its span, and with the approach to the peripheral sections the error increases to 6%. It is shown that the obtained expression of the maximum bending moment allows us to form the required number of additional equations for the disclosure of a statically indeterminate system of "gas pipeline-support", taking into account the possibility of fastening on stretch marks. The mathematical model is presented aimed at decomposition of overburden gas pipeline structures, which allows to model the SSS at each of the spans separately within the integral structure.. It is established that additional stretch marks reduce the maximum bending stress by 22%, and in case of loss of one of the stretches of the bearing capacity of the gas pipeline SSS increases by 11.1-14.8% depending on the previous stretch tension. The proposed mathematical model for the processing of discrete data forms the basis of the experimental-theoretical method of geodetic control of the gas pipelines’ SSS, taking into account their structural and technological factors.