Who can save the Mariinsky theater from destruction
In 1805 the first Russian textbook on mine surveying “Practical underground geometry” was published. This was a turning point in the formation of the specialty, without which 200 years later it is impossible to imagine either the development of minerals, or construction of subway lines, or the construction of underground passages or mine shafts.
Up to the 18th century, the technical level of mining was extremely low. Excavation of ore was carried out manually using shovels and hammers. To the surface, it was delivered on the backs of porters or by horse-drawn traction. Hard rocks were broken utilizing fire, which consisted of heating followed by sharp water cooling. The lack of fresh air and regular collapses made the working conditions extremely difficult.
As mining developed, the difficulties only increased. The use of blasting (“powder-shooting”) brought increased attention to searching means of protection both for the workers in the faces and for the objects above the mines. There appeared an urgent need for specialists, capable to establish boundaries of minefields, to make surveys of workings, and to coordinate them with surface surveys.
Within the walls of the Mining Corps (nowadays Saint Petersburg State Mining University), a surveyor’s class had existed since the foundation of the university in 1773. However, in the early years, the training and practical work of specialists was influenced by the German school. Let us remind that the oldest mining educational institution in the world - Freiberg Mining Academy - was founded eight years before the first technical university in our country.
Young people were sent to Germany for education, German experts were invited to work at mining enterprises of the Russian Empire, gauges and devices were imported.
With that first textbook of professor Alexey Maksimovich foreign manuals gradually began to be superseded by works of domestic authors. And 40 years later, Russian science was not only on a par with but surpassed colleagues from Germany. In 1847 another professor of the Mining Corps, Pyotr Olyshev, published a training course titled “The Art of Surveying,” which for the first time described how to use the theodolite in underground work. This aroused the indignation of the Germans, who tried to challenge the superiority of the Russians. But in the end, they had to retreat in the face of the undeniable fact that a similar German print edition came out a couple of years later.
For several centuries before that, a magnetic compass, half-circle, and the simplest linear measurements and serrations had been used underground. Given the level of mining production that existed at the time, they were more than enough. However, in the second half of the 19th century, with the increase in the scale of production, the requirements for the accuracy and reliability of surveying instruments and methods became stricter. Especially complex surveying was carried out in the coal mines, which began to go to deeper and deeper horizons and spread over large territories.
Before the revolution in Russia, a great role was played by the service of state surveyors (surveyor - staff officer rank 9th class of the Table of Ranks). Enterprises belonged to individuals, and the Mining Department, which was interested in the most rational mining operations, sent there their inspectors. In other words, local mine surveyors were subordinate to the owner of the mine, whose work was already controlled by the same state mine surveyor inspector.
After 1917 the system of the “tsarist” service caused a lot of criticism. And only in 1932, by the results of the First All-Russian Congress of mine surveyors, it was rebuilt to function in the new non-capitalist conditions. Some of the functions were transferred to Gosgortechnadzor (now Rostekhnadzor), and the mine surveying services were integrated into the mines and processing facilities.
The loss of specialists’ independence had negative consequences. On the one hand, they were subordinate to the management of mining production. Besides, they had to monitor the use of subsoil and were the “eye of the sovereign.” The mine surveyor recorded and still records the mandatory instructions in a special document - the Book of Surveyor’s Instructions. It is the first thing that the Gosgortechnadzor (Rostechnadzor) inspections are familiar with. Certificates on the fulfillment of planned indicators are signed only by the mine surveyor, who makes measurements of the work performed in the faces and checks against the plan. All the discrepancies become visible to the state authorities, for example, the fact of exceeding the admissible percentage of losses. At that time, the mistakes threatened the enterprise with reprimands, removal of managers from their positions, and deprivation of bonuses at the whole combine, today, with fines from the tax authorities or loss of license. In short, the situation requires cast-iron character on the part of the specialists.
By the way, at the same All-Russian Congress of Surveyors, it was decided to create the Central Research Bureau of Surveyors (TsNIMB), whose core staff was recruited from scientists of the Mining Institute. With time the SRI grew into the All-Union Research Institute of Mining Mechanics and Mine Surveying (VNIMI), which was recognized as one of the leading mining institutes of the country. Its employees were involved in strategically important areas for the development of the industry. In particular, they made several revolutionary scientific discoveries only in the first decades after their establishment: they developed basic ways of predicting shock hazard, preventing rock bumps in mines and mines, and managing rock pressure. This has significantly reduced the number of casualties in mining operations. In addition, VNIMI scientists created a method for modeling mining areas using equivalent materials in laboratory conditions, which made it possible to visually study possible variants of mining development and plan them.
In addition to the mineral complex, another direction of development of the art of surveying was the construction of the subway. In Moscow, the work started in the 1930s, in Leningrad - in the early 1940s. But the outbreak of the Great Patriotic War interrupted the process. Mining engineers were subject to compulsory armor as personnel working directly or indirectly for the defense. Both on the home front and the front line, their civilian specialty was indispensable
Today, both accumulated experience and the latest trends in the industry are juxtaposed here. Next to the Museum of Surveying, students carry out practical work at a modern surveying and geodetic testing site and in the laboratory for new instruments. In 1950 graduates of the university had developed and tested a unique device - the 600 kg gyro compass M-1, which allowed for gyroscopic orientation of mine workings in the Donbas, Krivoy Rog, and Kuzbass.
At present, students have the opportunity to study and university staff to carry out scientific and contractual work using the world’s most precise Gyromat 3000 gyrocompass. There is only one copy of this gyroscope in St. Petersburg, and there are several more in Moscow. When there is a need in its application, companies apply directly to the educational institution. For example, it was used during the construction of the subway section between the stations “Primoskaya” and “Begovaya” in 2016.
No less interesting project awaited surveyors in connection with the underwork of the Mariinsky Theater. The management of the object of cultural heritage has already repeatedly complained about the significant sagging of the floor in the building (by 12 cm!) and appeared cracks on the walls, linking the process with the construction of the Teatralnaya metro station nearby. But when its artistic director and director general Valery Gergiev discovered the hole in the floor right in front of his office, that was the last straw.
From the archive of the experts of the Mountain University
Let us remind that the construction of the station began in 2015; it is planned to be put into operation in 2024, and the exit from the subway - to make either directly on Teatralnaya Square or at the corner of Lermontovsky Prospekt and Dekabristov Street.
“The first surface subsidence that reached the walls of the historic building began to appear in 2017 when the vertical shaft of mine No. 574, the shaft workings, and the first tunnel had already been built. They were minor and could not significantly affect the theater. Mining operations gradually progressed - most of the auxiliary workings were passed, some of which were located directly under the Mariinsky Theater. In 2020, construction began on the main station tunnels near the intersection of Matveyeva Lane and Dekabristov Street. By the summer, settlements had already reached the levels at which it was necessary to control the development of deformations of the building. Gradually, new cracks began to appear in the interior of the theater and the old ones began to open," says Evgeny Volokhov, associate professor of the Department of Surveying at the Mining University.
The Committee for Transport Infrastructure Development appealed to the university specialists in mine-surveying and construction to get to the gist of the problem. A group of experts was formed at the university.
According to Evgeny Volokhov, who joined this working team, they had the following tasks: to analyze the mining situation on the “Teatralnaya“underground complex; to determine the presence of the influence of mining works on the building of the Historical Stage, and to identify the degree of their danger. In order to speed up the research, the head of the main opera theater of the country personally called the rector of the university Vladimir Litvinenko, expressed his concern and offered to take the situation under independent control until the end of the underground construction.
Moscow design organization, initially involved in the work, conducted only geodetic monitoring of deformations without interpretation of observations. This is a higher level of work, which evaluates the current and future impact of the tunnels on the surrounding buildings and structures. Scientists undertook an examination, a detailed analysis of the situation, making a conclusion, and identifying the real risks.
"It was found that mining operations under Theatre Square had an unambiguous impact on Mariinsky. This was confirmed by both estimated calculations and data from monitoring observations. And although the level of impact as of September 2020 did not allow us to speak about the danger of disturbance of bearing capacity of structural elements of the building, the forecast of development of surface subsidence during further development of mining works showed the existence of risks of exceeding the levels of allowable deformations for the building. Moreover, in the course of the study, global gaps in the regulatory provision of protection of buildings and structures in underground construction in Russia were revealed. There are no special documents on the problem, the criteria for assessing the impact are not established, the measures to protect buildings from deformations have not been approved. Known traditional approaches for mine surveying are not used in modern design practice. In other words, the protection of buildings is practically not regulated", - emphasizes Evgeny Volokhov.
Researchers at the university have developed a package of recommendations designed to preserve the nineteenth-century theater building. They concern mining technologies, the exclusion of some elements of the underground complex, and changes in terms of deformation monitoring work. Both the Metrostroy and the CDti have ensured their coordination and observance. In addition, university experts continue to monitor mining operations and the development of deformation on the surface. Surveyors have identified “pressure points” where special control should be provided in excavations and rock mass, on the surface, and in the building structures, and developed methods of control, observation, and interpretation of data.
Today, the level of deformations on the surface near the Historical Stage coincides with the forecast updated by the university, and in the area of the main mining workings of the station workings, the levels are even significantly lower than predicted. This indicates the effectiveness of the measures taken. However, until the mining and construction, and installation works of the Teatralnaya station are completed (end of 2021 - beginning of 2022) the surveyors’ peaceful sleep is "not to be expected...”