ON THE ISSUE OF THE DURATION OF MINE CONSTRUCTION IN KUZBASS AND WAYS TO REDUCE IT

S. N. LEONT’EV

Over the forty years of Soviet power, coal production in Kuzbass increased 54-fold and in 1957 reached 68.2 million tons. This increase took place through the construction of new mines during the years of the Soviet five-year plans, since the mines of the pre-revolutionary period were either worked out or completely reconstructed.

The technology and organization of mine construction over the forty-year period have grown immeasurably. From seasonal construction on the surface they moved to year-round construction; manual labor and horse haulage in the mine and on the surface were replaced by mechanized methods; mine construction was equipped with powerful and diverse equipment, with the introduction of a significant degree of prefabrication; horse transport on the surface was replaced by motor transport; electricity replaced steam. A production and material-technical base has been created for construction and continues to be created. However, manual labor in mine construction still has a large share; prefabrication is insufficient, and a number of mine-driving and construction processes do not have stable mechanization.

The construction of coal enterprises lags behind the development plans of the national economy of the USSR. The actual duration of construction of coal enterprises is greater than provided for by the standards. In standards N 135—56, approved by Gosstroy of the USSR, the normal durations of construction of enterprises and facilities are established, in particular, for the construction of coal mines in different basins. For the construction of mines in Kuzbass with capacities of 600, 900, and 1200 thousand tons, the duration is set at 40, 48, and 58 months, respectively. For undeveloped regions the duration of construction is increased by 20%. The duration of the preparatory period is set at no more than 25% of the total construction period.

Practice shows that the duration of construction and the capacity of mines have not a linear, but a complex power-law dependence. The construction periods for mines with capacities from 600 to 2400 thousand tons that are closest to the established standards are given by the expression \(T = kM^n\), where

\(T\) — duration of mine construction, months;

\(M\) — mine capacity, thousand tons;

\(k\) — numerical coefficient;

\(n\) — exponent.

The numerical values of \(k\) and \(n\) depend on basins and types of mining enterprises.

For the conditions of Kuzbass, on the basis of the analysis carried out, the numerical values of the coefficient \(k\) and of the exponent \(n\) for mines with a capacity of up to 2400 thousand tons were determined: for developed districts, respectively, 2.3 and 0.45; and for undeveloped districts, 2.76 and 0.45.

This expression makes it possible to determine, for normal construction conditions in developed and undeveloped districts, the approximate total duration of mine construction and, proceeding from it, the preparatory period as well.

Figure 1 shows curves for determining the design duration of total construction for developed and undeveloped districts, and the numbered points show the actual construction periods of ten Kuzbass mines that have been put into operation (Table 2).

Fig. 1. Duration of construction of Kuzbass mines.
I—duration on the basis of standards for developed districts;
II—duration on the basis of standards for undeveloped districts.
Points 1, 2, 3 ... 10 show the actual construction duration of 10 Kuzbass mines.

The main reasons for the lag in mine construction, as in the construction of enterprises in other branches, are:

1) improper planning of construction, as a result of which financing is scattered among many projects;

2) insufficient provision with material and technical resources;

3) untimely provision of designs;

4) low labor productivity;

5) incomplete utilization of the available mine-driving and construction equipment;

6) an insufficient degree of prefabrication in mine construction;

7) insufficient use of advanced domestic and foreign experience;

8) unsatisfactory organization of work;

9) labor turnover, which is especially characteristic of mine builders, for the following reasons: loss of part of the personnel of underground and surface mine builders when newly built mines are handed over for operation; failure to provide shaft sinkers with work corresponding directly to their qualifications; failure to provide mine builders with normal living conditions.

Division of construction time into periods and stages

We divide construction time into the preparatory and main periods. The classification of mine construction by periods and stages is given in Table 1.

The reduction of mine construction periods depends on reducing the duration of the preparatory and main periods and of their stages, which are generally carried out consecutively. The preparatory period, for which standards allocate up to 25% of the total construction time, actually takes 2–3 years. The reduction of construction times in the main period depends chiefly on the duration of mining work. Construction work and, as mining work is completed, installation work of the main period can be organized on a broad front, with a high degree of prefabrication and mechanization. Therefore, with proper organization, they require less time to perform.

Table 1

Continuation of Table 1

of time than mining works. However, there are cases when the completion of mine construction is delayed by surface construction, systematically postponed because of a lack of financing—for example, in Kuzbass mine No. 13, the “Tomusinskaya 5/6” mine, and others.

Duration of Mine Construction in Kuzbass

The actual and standard durations of construction, and expenditures by year as percentages of the total cost for 10 Kuzbass mines put into operation, are given in Table 2.

Table 2

Table 2 shows that the actual duration of mine construction in Kuzbass, as a rule, increases with their capacity; that the average total duration of construction for the 10 mines put into operation is 1.4 times greater than the standard, and for the preparatory period, 1.6 times greater. The standard distribution of capital expenditures and actual fulfillment by years of construction for Kuzbass mines, as percentages of the construction cost, is given in Figs. 2, 3, and 4.

It should be noted that during the first three years of construction the actual fulfillment in monetary terms amounts to from 7.5 to 20% of the cost, instead of the 42 to 70% provided for by the standards. The actual fulfillment during the first three years at 6 mines out of 10, and during two years at

at all the mines of Kuzbass does not ensure the fulfillment of the volume of work established by the standards even for the preparatory period. The exception is the construction of mine No. 10, which was completed in a shorter time than prescribed by the standards and took 70% of the normative time determined by us (curve 3, in Fig. 3).

Fig. 2. Volumes of work according to the standards and actual volumes by years of mine construction: 1 and 1′—standard and actual for mine No. 6; 2 and 2′ for No. 1; 3 and 3′ for No. 2

Fig. 3. Volumes of work according to the standards and actual volumes by years of mine construction: 1 and 1′—standard and actual for mine No. 7; 2 and 2′ for No. 4; 3 and 3′ for No. 10

The curves in Figures 2, 3, and 4 also show that in individual cases the annual volumes of work performed are greater than the standard ones; for example, at mine No. 2, in the fifth year of construction, 41.6% was completed; at mine No. 4, in the seventh year of construction, 33% was completed; at mine No. 6, 35.5%; at mine No. 9, 34.6% of the total estimated cost of construction.

Fig. 4. Volumes of work according to the standards and actual volumes by years of mine construction: 1—standard for all four mines; 1′, 2′, 3′, 4′—actual performance respectively for mines No. 3, No. 9, No. 5, and No. 8

The volume by the time of commissioning is approximately 83% of the total construction cost. The actual duration of construction of coal mines in the USSR is 1.3–1.8 times greater than the standard duration. There are no data on the duration of construction of coal mines abroad. When it is necessary to accelerate construction, the rates of erection of individual buildings and structures, as well as the rates of shaft sinking abroad, are high. For example, the average monthly rates of sinking the shaft of mine No. 2 in South Africa, more than 2000 m deep, over 20 months amounted to 91.9 m; the shaft of the “Monarch” mine was sunk 987 m in five months, or an average of 197.4 m per month.

In the USSR, the average monthly rate of sinking the shaft of mine No. 5/6 named after Kalinin, 450 m deep, was 100 m.

Main Directions for Reducing the Duration of Mine Construction

Preparatory Period

The duration of the preparatory period, according to design standards, is planned at up to 25% of the total construction time, and under difficult conditions it may be greater. The main measures ensuring a reduction in the duration of the preparatory period include:

Reducing the labor intensity of construction-and-installation work by creating a mobile, integrated construction base, put into operation at new construction sites from the first days of the preparatory period.

Increasing the degree of prefabrication of temporary and permanent buildings and structures erected during the preparatory period. It should be noted that foreign practice provides examples of the prefabricated construction of small residential houses on prepared foundations within several hours (England).

Maximum mechanization of work by means of construction equipment specially selected for the specific conditions of the preparatory period.

Carrying out work in accordance with a schedule that ensures priority construction of motor roads, housing, temporary and permanent construction facilities, etc.

Organizing management appropriate to the scope and conditions of construction, good selection of personnel, and broad involvement of specialized construction organizations for the construction of motor and rail roads, bridges, power lines with voltages of 35 kV and higher.

Main Period

Driving Horizontal Mine Workings

In the driving of vertical shafts by ordinary and special methods, high monthly rates have been achieved in all coal basins of the USSR, and much work has been devoted to high-speed shaft driving. Work is also being carried out on the further improvement and study of methods for increasing the commercial rate of shaft sinking. The rates of driving extended horizontal and inclined capital and main preparatory workings, especially in rock and under gas-regime conditions, are still insufficient. The volume of work involved in driving horizontal and inclined workings in the construction of mines in Kuzbass is usually three to four times greater than that of vertical workings. Therefore we shall consider only certain directions for reducing the time required to drive horizontal capital and main preparatory workings. To ensure completion of the volume of mine workings required for handover within the standard construction periods for mines, there are two methods.

The first method is the organization of high-speed driving of workings in one principal direction and the development of mining operations as new working faces are opened and their rational ventilation is ensured.

The second method is the organization of the driving of workings in several, usually two or three, parallel directions, of which one is the main direction and the others are auxiliary, for the simultaneous driving of workings—for example, the main and ventilation horizons and for preparing the line of the extraction face in separate seams.

The first method is used when the volume of mine workings to be commissioned is small and the total length of the workings in the main direction is not great. The second method is used when there is a large volume of mine workings to be commissioned, a great length of workings driven successively in one direction, difficulties with ventilation, and when it is possible or necessary to organize auxiliary directions. The second method shortens the time required for carrying out mining work by 10–20 months, and sometimes is the only possible one. Examples of the use of the second method are the design schedules for driving mine workings in the Donbass—at the “Ignatievskaya” mine and the “Krasnolimanskaya” mine; and in Kuzbass at the mines: “Chertinskaya Yuzhnaya,” “Baidaevskaya Severnaya,” “Egozovskaya No. 1,” “Kapitalnaya No. 3,” and others.

The use, for ventilation, cables, and other purposes, of auxiliary boreholes, as well as the equipping with hoists of blind shafts, raises, or auxiliary mine-boreholes, is intended to organize preparation, by counter-heading faces, of the ventilation horizon or of individual seams.

For driving horizontal and inclined workings in the main and auxiliary directions, it is necessary to ensure uninterrupted cage hoisting, reliable temporary drainage, sufficient temporary ventilation, and uninterrupted underground and surface haulage of coal and rock. There are examples of very poor organization: at one mine, for many months after completion of shaft sinking, a bucket hoist instead of a cage hoist was used for driving horizontal workings; at another mine, the driving of haulage workings was not carried out according to the design profile, which caused extensive additional work.

Strict adherence to the designed calendar schedule of mining work, taking into account the priority driving of ventilation workings and of the main direction, as well as workings used for construction purposes and to facilitate the driving of other workings. Organization of high-speed driving of priority workings.

Systematic improvement of tunneling and construction equipment and its proper and full utilization.

For good organization of work at the face, ensuring high rates of high-speed driving of workings—on the order of 200–500 m per month—in addition to cyclic organization according to the principle of 2–3 cycles per shift, transition to a prefabricated permanent support, and solution of the problem of rapid exchange of mine cars, it is necessary: 1) to saturate the face with the necessary amount of equipment and workers, taking into account the planned increase in their labor productivity; 2) to introduce setting mechanisms and long-stroke, high-frequency drilling hammers, to increase compressed-air pressure, and to use wet drilling for greater silicosis safety; 3) for mines with hydraulic coal extraction—to introduce hydraulic drilling machines and mechanical hydraulic drivage machines.

A special issue is the introduction into mine construction, in particular in the driving of horizontal workings, of light alloys for the manufacture of pneumatic supports, shelves for drilling and for erecting permanent support by manual methods, the creation of lightweight temporary support, etc. It should be borne in mind that light alloys based on aluminum tend to become widely used in technology and in everyday life, and abroad there are examples of their use in building construction.

Of particular importance is increasing the productivity of drivage—

... which in Kuzbass is considerably lower than abroad and has large unused reserves.

Surface Construction

The volume of work for the construction of buildings and structures on the surface, including the residential settlement, amounts to approximately 65% of the total cost of mine construction. The principal measures ensuring a reduction in the construction period for surface buildings and structures and for the residential settlement include:

The complete completion of the work of the preparatory period, ensuring normal or accelerated construction in the main period, including the creation, by the beginning of the main construction period, of the necessary construction base.

Proper scheduling of the construction of facilities, ensuring their timely handover for installation, as well as the priority execution of underground utilities and all zero-cycle work.

A reduction in the labor intensity of erecting all surface buildings and structures by increasing the degree of prefabrication, in total for all types of materials, to 1,000 m³ per 1 million rubles of the estimated cost of construction-and-installation work, instead of the designed 300–400 m³; raising the level of comprehensive mechanization of construction work and reducing labor inputs per 1 m³ of surface buildings and structures.

Uninterrupted provision of construction with the necessary materials and prefabricated elements and structures in accordance with the schedule for their receipt. Reducing the weight of the structures of buildings and structures through the use of lighter concretes, hollow structures, etc. Combining work in time at several construction sites and organizing work in two shifts.

In order to improve the quality of construction, it is necessary to organize thorough acceptance, in terms of quality, of the work performed; the storage and transport of prefabricated elements; proper assembly and grouting of them; fulfillment of all technical conditions and technological rules for the execution of work; and training workers in new qualifications. With large volumes of work, it is advisable to carry out specialization in the construction of prefabricated buildings and structures.

Considering that precast reinforced concrete and prefabricated structures made of other materials make it possible to reduce severalfold the construction period of the surface parts of buildings and structures, it is necessary to pay special attention to improving the technology and organization of the erection of their underground parts, the construction of which still takes a great deal of time.

General Considerations

Measures to reduce the construction periods of coal mines may be divided into three groups.

The first group consists of measures that depend on higher-level organizations—Gosplan, the sovnarkhozes of economic regions, and Gosstroy—including: proper planning of the volumes of work at construction sites; supplying construction projects with material and technical resources; creating a rational organization of construction management, taking into account expedient specialization; establishing appropriate standards for the loading of construction and mine-driving equipment, etc.

It should be noted that planning a large number of construction projects with different construction periods, different costs, and different standards...

the distribution of funds by year is a very difficult task, possible on the scale of basins and mine-construction combines, but not on the scale of individual mine-construction trusts. It is easier to regulate the construction of surface buildings and structures, which have a share of up to 65%; it is more difficult to regulate mining works, with a share of up to 30%, and installation works, with a share of ≃5%. It is therefore no accident that specialized trusts and construction administrations are being organized for installation, road, and railway works on the scale of basins or combines (Kuzbass, Karaganda, Mosbass).

The organization of the rational use of scarce construction-and-installation and mine-driving equipment of different construction organizations, with the overcoming of departmental interests and at the same time the prevention of depersonalization, represents a large and serious task. Also important is the question of organizing and rationally using specialized trusts and administrations and a construction base on the scale of economic regions, in particular for Kemerovo Oblast.

The second group comprises measures that depend on design institutes; these include the high quality and timeliness of design-and-estimate documentation, with the necessary lead time. The designs must take into account maximum prefabrication and the standardization of prefabricated elements and structures, and must provide good organization of construction: general, for individual construction sites, and for priority facilities. Working designs for priority facilities and zero-cycle works must be issued in a timely manner so that they can be carried out in the preparatory and at the beginning of the main periods.

The third group comprises measures that depend on construction organizations; these include many questions.

It should be noted that construction-organization designs for facilities quickly become obsolete, and for proper organization it is necessary to have, in trusts and construction administrations, good construction-preparation departments capable of taking into account specific conditions and advanced domestic and world construction experience.

Conclusions

Among the important organizational conditions for the further improvement and reduction of the construction periods of coal enterprises, the following should be included:

Proper planning of the volumes of work by years of construction in accordance with work-organization designs, ensuring the normal development of mining works and surface construction. At the same time, planning must take into account, on the scale of the basin and the trusts, normal work reserves at all stages of construction.

The concentration of material and technical resources and financing on facilities under construction, without allowing a reduction in the pace of construction projects already begun.

An increase in the load-carrying capacity of motor-transport equipment and in the degree of mechanization of loading and unloading operations, increasing the radius of operation of motor haulage and making it possible to increase the weight of standard prefabricated structures and units. This requires the priority construction of good motor roads, storage yards, and approaches to the buildings and structures under construction, as well as a carefully thought-out organization of assembly.

The use of advanced domestic and foreign construction experience. It is impossible to ignore or fail to use existing...

... the great experience being accumulated in the highly developed capitalist and democratic countries.

Increasing responsibility for construction cost and control of prime cost will be a powerful lever for shortening the time and reducing the cost of construction, since the construction period and its cost are closely interconnected.

Reducing the cost and improving the quality of prefabricated structures—reinforced-concrete, concrete, and those made of other materials—will be important factors in their introduction. This requires simplification and standardization of prefabricated structures, specialization of plants for their manufacture with a reasonable transportation radius, the establishment of stricter tolerances, and rigorous rejection on the basis of quality.

The introduction of new equipment that lightens labor, reduces the labor intensity of construction-and-installation work, increases labor productivity, shortens the duration of mine construction, and, ultimately, reduces the cost of construction and mine-driving work.

Delivery, for uninhabited districts characterized by the absence of roads and by a minimal construction base, at the beginning of the preparatory period, by motor-tractor transport, and sometimes by airplanes and helicopters, of a complete mobile and prefabricated/demountable repair and construction base, prefabricated residential houses assembled on ready foundations within several hours, construction-mechanization equipment and other material resources, as well as the necessary personnel, in order to carry out quickly the work provided for the preparatory period.

The organization of high-speed construction on the principles set forth, with greater provision of material and technical resources, a higher degree of prefabrication and integrated mechanization, and the use of a mobile construction base and powerful means of transport, will make it possible to reduce significantly not only the actual construction periods, but also the newly established standard construction periods.

LITERATURE

1. Balbachan Ya. I. Ways of accelerating mine construction. MT i TR, No. 8, 1955.

2. Dygai N. A. Report at the All-Union Conference of Builders, 1954.

3. Melnikov L. G. Construction of coal-industry enterprises at the level of new tasks. Ugol’, No. 10, 1955.

4. Raizer D. Ya. Report at the All-Union Conference of Builders. Stroitel’naya promyshlennost’, No. 12, 1954.

5. Abramenko T. F. On the question of ways to shorten the preparatory period in the construction of coal mines. Ugol’, No. 9, 1956.

6. Kalmykov E. P. Accelerate the rates of sinking vertical shafts in the sixth five-year plan. MT i TR, No. 9, 1956.

7. Advanced methods of construction in Kuzbass, 1956.

8. Aganbekov K. I. Experience in high-speed driving of crosscuts at mine new-construction sites in Kuzbass, 1955.

9. Foreign technology. Driving preparatory workings in France, 1955.

10. Experience of construction abroad. The construction exhibition “Olympia” in London, 1956.

11. Foreign technology. Sinking the shaft of the Monarch mine, 1956.

12. Stanchenko I. K. On certain factors predetermining the duration of construction periods for mines and open-pit mines. Shakhtnoe stroitel’stvo, No. 3, 1957.