METHODS OF DEFINING THE DIRECTION OF UNDERGROUND WORKINGS: REVIEW AND COMPARATIVE ANALYSIS

ABSTRACT

The accuracy of specifying the direction of underground workings is the main factor in the design and construction of tunnels, drifts and underground workings. Errors in determining the direction lead to an increase in the volume of mining operations, additional costs and increased danger. The article provides an overview of the main methods for setting the direction, a comparative analysis of their accuracy, applicability and technological features. Traditional optical and geometric methods, modern digital and automated systems are considered.

АННОТАЦИЯ

Точность задания направления подземных выработок является главным фактором при проектировании и проведении тоннелей, штреков и подземных выработок. Ошибки в определении направления приводят к увеличению объёмов горных работ, дополнительным затратам и повышенной опасности. В статье представлен обзор основных методов задания направления, проведён сравнительный анализ их точности, применимости и технологических особенностей. Рассмотрены традиционные оптические и геометрические методы, современные цифровые и автоматизированные системы.

Keywords: geodesy; mine surveying; the direction of the underground workings.

Ключевые слова: геодезия; маркшейдерское дело; направление подземных выработок.

INTRODUCTION

Setting the direction of underground workings is the process of establishing the design trajectory of tunnels, drifts and other mining workings with high accuracy. This process ensures: correct compliance with the design line and slopes; minimizing counter errors when passing from multiple fronts; safety of underground operations and rational use of resources.

There are several main groups of methods for setting the direction: traditional geometric, optical, and modern digital technologies.

1. Traditional methods of setting the direction

1.1. The polygonometric method

Polygonometry is based on the construction of a surveying network of points connected by lines (polygons). Main features: high accuracy at short and medium distances; requires regular checkpoints; errors accumulate with increasing polygon length.

It is used in drifts, tunnels and deep mine workings in the absence of direct visibility.

1.2. Leveling and serifs

Leveling provides control of the slopes and the elevation position of the workings. Serifs using optical devices allow you to set the direction without direct visibility of the target.

Disadvantages: difficulty in crossing a complex array; labor intensity;

dependence on the stability of the reference points.

1.3. Optical devices (theodolites and levellers)

They are used to transmit azimuths and angles in underground conditions. Features: accuracy of up to several seconds of arc with proper adjustment; high dependence on visibility conditions and quality of tools; traditionally the main tool in underground surveying.

2. Modern methods of setting the direction

2.1. Gyroscopic and inertial systems

They are used where it is impossible to navigate the surveying network. Advantages:

independence from visibility and geological disturbances; the ability to set directions over long distances; errors accumulate more slowly than with polygonometry.

Limitations: high cost of equipment and the need for periodic calibration.

2.2. Laser systems and laser sights

They allow you to: transmit direction and control points in real time; minimize errors due to the human factor; use for straight and curved workings.

2.3. Digital modeling and automation

Modern methods include the integration of 3D models of deposits, robotic total stations and drilling equipment monitoring systems. Dignities: high accuracy and minimization of manual labor; the ability to analyze possible deviations and adjust the trajectory; integration of data with GIS and digital counterparts.

3. Comparative analysis of methods

Table 1.

Comparison of methods

Conclusion: traditional methods remain relevant for short and medium workings, while modern digital and gyroscopic systems are most effective in long and difficult sections.

4. Conclusion

Setting the direction of the underground workings is an important task for the surveyor. Each method has its advantages and disadvantages. Traditional methods (polygonometry, leveling, optical instruments) remain reliable under simple conditions. Modern technologies (gyroscopes, lasers, automated systems) make it possible to ensure high accuracy in complex and extensive workings.

References:

1. Agafonov, G. A. Surveying, Moscow: Nedra Publ., 2018. A classic fundamental textbook describing the basics of surveying measurements, including methods for setting directions, calculating polygonometry and leveling.
2. Nikitin, N. A., Serov, V. I. Surveying in mining. Moscow: Gornaya kniga, 2016. It describes in detail the methods of transmitting direction during tunnels and drifts, the use of theodolites, serifs and control measurements.
3. Grishin, M. M. Geodesy and surveying in underground conditions. St. Petersburg: Nedra-Businesscenter, 2015. It highlights traditional methods and modern tools: laser devices, gyroscopic systems, automated total stations.
4. Torge, W., Müller, J. Geodesy. 4th ed. — Berlin: de Gruyter, 2012. An international publication containing the general theory of geodetic measurements, including inertial and gyroscopic systems used in underground surveying.
5. Heiskanen, W., Moritz, H. Physical Geodesy. — W. H. Freeman, 2015. It is suitable for a deep understanding of instrument error, the theory of inertial systems and orientation used in conducting long tunnels.
6. Moser, G., Schenkel, R. Modern Tunnel Surveying. — Springer, 2017.
7. Instructions for the production of surveying work at coal industry enterprises. Moscow: Ministry of Energy of the Russian Federation, 2020.