Vol 59 Iss. 1

In 1967 was the 100th anniversary of the birth of Professor Vladimir I. Bauman, an outstanding representative of mining science, public figure and the largest Soviet mining surveyor. In February 1968, a jubilee meeting was held at the Leningrad Mining Institute dedicated to this date, with the participation of surveyors, miners, geologists and geophysicists.

When solving various technical problems there is a need for automatic and sufficient detection of underwater objects. The most effective method in this case is sonar (hydroacoustic).

In the presence of a gradient of sound propagation velocity in the location medium, the trajectory of sound rays deviates from straight lines perpendicular to the surface of the sound wave front. Refractive deflection of the rays occurs in the direction of the region of the medium with a lower sound propagation velocity. Obviously, the curvature of sound rays leads to a shift of the sonicolocation irradiation spot on the reflecting surface of the location object. This displacement determines the error of the sonicolocation measurement, and in some cases can lead to the formation of an acoustic shadow zone in which sonicolocation measurements are practically impossible.

The sonar method of surveying control and surveying of mine workings is used in the practice of mining enterprises relatively recently.Currently, this method of distance measurement is used in the surveying of dredge ranges, deep open-pit ore passes, inaccessible underground salt leaching chambers and underground storage of petroleum products, as well as mine shafts and boreholes drilled by boring.

The use of single-vibrator acoustic systems in sounders for surveying inaccessible mine workings is dictated by the desire to improve their technical and economic characteristics. It is obvious that combining in one electroacoustic transducer the functions of the emitter and receiver of acoustic signals allows to increase the accuracy of measurements, simplify the design, reduce the size and weight, as well as reduce the cost of the acoustic system.

To date, the issues of selecting the optimal parameters of input circuits have not been given sufficient attention in the development of pulsed ultrasonic equipment and, in particular, ultrasonic locators used in mining. When designing input circuits, methods known from general radio engineering are usually used, which do not take into account the specifics of ultrasonic devices.

In the process of drilling and supporting technical wells of large diameter (1.0‑3.6 m) there are a number of technical problems, the solution of which is possible only if the geometry and dimensions of the borehole (curvature of the axis, the size of wall enlargement, etc.), as well as the position of the support during its construction are known. Wells are drilled vertically up to 1000 m deep. Drilling is carried out with the use of a flushing fluid, for which a clay solution with a specific gravity of up to 1.25 g/cm² depending on the strength of the rocks is used.

In modern ultrasonic technology, in particular in sonar surveying devices, piezoelectric transducers of electrical energy into acoustic energy are being used more and more frequently. Piezoelectric radiators made on the basis of barium titanate and lead zirconate titanate ceramics, in comparison with vibrators made of other materials, are characterized by high efficiency and specific radiated power, as well as manufacturability and low cost.

One of the ways to reduce the cost of surveying sonar devices is the use of a single electroacoustic transducer as a sound emitter and receiver. In sounders with separate receiver and transmitter, the axes of directional characteristics of the transducers are usually separated by some distance, which makes it difficult to receive signals reflected from the near parts of the target surface. This disadvantage is completely eliminated in single‑vibrator locators, since the directivity characteristics of the same electroacoustic transducer in the modes of emission and reception coincide.

Currently in the USSR more than 75% of the volume of rock mass of placer deposits is processed by dredges. The plans of development of the national economy for the next few years provide for a significant increase in dredge construction, especially through the commissioning of powerful dredges (380, 400, 500 m) with deep digging capacity. ...

Исправлений перевода не потребовалось.

When servicing drilling and blasting operations in an open pit, a surveyor needs to determine the actual location of the blasted bench and the actual parameters of drilling and blasting operations , as well as the characteristics of structural features (fracturing) of the rock mass.

During the years of Soviet power our educational institutions trained many highly qualified specialists, for whom mining enterprises had a great need.

Theodolite traverses laid along underground workings are calculated gradually, as the workings advance. For some time the traverses remain free, then they gradually form closed polygons, to a greater or lesser extent interconnected. Connection of the underground reference network to the redundant initial data (direction angles of the sides, determined by the gyroscopic method, coordinates of points transferred from the surface through vertical or inclined workings) is carried out relatively rarely.

Systems of theodolite traverses and polygonometry of Classes 1 and 2 are adjusted in a simplified way. First, corrections to the angles are jointly determined, then coordinate increments are calculated from the corrected angles, after which abscissas and ordinates are adjusted separately in the traverse system. The closures of individual traverses along the coordinate axes are distributed among the coordinate increments in proportion to the length of the sides.

The study and analysis of approximate methods of equalization is of great practical importance. It is obvious that in all cases, approximate methods of equalization give results less accurate compared to the results that can be obtained by equalization by the method of least squares (provided that it is correctly applied). Therefore, the practical use of approximate methods is due only to the desire to reduce the labor intensity of equalization calculations.

The article deals with the methodology of construction and transformation of graphs of systems of normal equations for determining the weights of unknowns in relation to the adjustment of geodetic networks by the method of indirect measurements.

A two-liquid compensator, i.e. an optical stabilizer based on the use of the interface surface of two liquids, was proposed by N. A. Gusev in 1958. The introduction of the upper liquid layer into the compensator ampoules had the purpose of damping the oscillations of the lower liquid. ...

Capillary rise of liquid in the ampoules of optical compensators can cause deterioration of the image quality of the telescope. To determine the inner radius of compensator ampoules with a large light aperture, formulas have been proposed. …

Double‑image rangefinders have linear graduation with divisions of 1 or 2 cm. As the distance increases, the image of the strokes of the staff scale decreases, becoming unclear. On this basis, the maximum distances for measurement should not exceed 200‑250 m. To eliminate this disadvantage, the factory "Carl Zeiss" (GDR) has created a precision double‑image rangefinder as an attachment to the Theo 030 (Theo 020) theodolite, using the method of logarithmic tacheometry, proposed in 1878 by Tichy. ...

Interpolation polynomials of various kinds are used to equalize spatial phototriangulation networks, suggesting that there is a dominant influence of systematic errors. However, studies in recent years have shown that random phototriangulation errors are commensurate with systematic errors, and sometimes may even exceed them. ...

The rigorous equalization method described is developed on the basis of differential error formulas of routing network elements. When transverse parallaxes are observed at six standardly spaced points, there is one redundant measurement that yields a conditional equation. ...

Photogrammetric methods are widely used for non-topographic purposes and, in particular, in construction to determine deformations of engineering structures. A number of works devoted to this topic have appeared in recent years and some experience has been accumulated in this field. However, researchers often either copy the methodology and principles of aerial photography, which complicates and complicates the necessary calculations, or simplify the method to such an extent that it becomes suitable only for architectural measurements or for determining large absolute values of deformations (2–3 mm).

Visual method of compiling primary geological documentation based on sketches, as is known, has a number of disadvantages, the main of which are subjectivity and relatively low accuracy. The quality and completeness of such documentation depend on the qualification of the performer.

The accuracy of coordinates determination from images and determination of internal orientation elements can be significantly affected by the surface quality of photographic plates, which is understood as deviation of their surface on the emulsion side from the plane. This deviation leads to displacement of the image of photographed objects on the negative and to increase of distances between images of coordinate marks of the camera's application frame. ...