Over the course of several centuries of its existence, the Moscow metro has acquired a variety of fantastic stories and very real facts, many of which have received their vestments in the literary word. But how, in accordance with what principles and norms, this truly great structure is being built, which has long ago become an integral attribute and symbol of the capital of Russia.
Planning
Planning the direction of new lines begins with an analysis of their feasibility, that is, the densely populated neighborhoods and industrial zones, which will soon be lucky enough to find their own metro station. However, this factor is not at all decisive when choosing an object for construction, because the strength and longevity of the underground complex largely depend on the conditions of geodesy and ecology, which, contrary to the wishes of a person, may simply not allow any construction work to be carried out.
The first and, perhaps, the most important stage of building a metro is the design process, it is he who determines the depth at which the new tunnel will be laid, its length, the type of design features and supports used. We should not forget about the need to take into account a number of points related to existing buildings, buildings of historical value, monuments, monuments that can receive irreversible damage as a result of vibration and noise, which is an integral element of the modern city metro.
It is interesting that ordinary highways allow for work that can hardly be called deep, metro lines in such sections have a depth not exceeding 20 meters. What is difficult to say about densely populated areas, characterized by a large concentration of residential buildings, requiring special construction techniques in a deep, closed way, that is, not involving the opening of the top layer of the soil.
Gnawing into the bowels
As you might have guessed, the laying of a new branch begins with the formation of a kind of mine, it is through it that the necessary equipment and a team of workers will go down in the future, continuously transporting hundreds of tons of earth upward, obtained as a result of laying a horizontal branch, which will soon turn into a new tunnel for passing the train.
Relatively little time is required for the construction of the station itself, equipped, if necessary, with a system of escalators and underground passages.
Any new line is equipped with platforms, halls, which, depending on the depth of the installation, the presence of special columns and train lines, can be one-, two, three- and even multi-span, connected by a system of special transitions.