Competition project
The competition for the concept of reconstruction of the Luzhniki pool was held in the spring of 2014 by order of Codest, and we talked about it in sufficient detail. The 1956 building needed to be rethought, turning the outdoor pool into an indoor water park, preserving the facades as much as possible - a good example of the Stalinist Empire style. The competition took place in two stages, and the finalists, finalizing their projects in the second round, were required to develop all sections of the concept, including engineering and economic, in great detail: not as is usually the case in architectural concepts, rather figurative than detailed.
So the engineering part of the concept of the "Lost World" project proposed by the consortium led by Asadov's architectural bureau, developed by the specialists of the Engex company, deserves a separate consideration. Recall that the essence of the project is the transformation of the antiquated Stalinist peripter into a romantic ruin, hiding inside the luxurious natural world of a cascading oasis. The spatial culmination of this multi-level water garden is a block of premises that covers the existing complex, shifted towards the Grand Sports Arena and cantilever over the summer terrace.
Hiding a new volume inside the old walls, voluntarily displacing it from at least one axis - is not a new topic for reconstruction, but it always gives interesting results. And when the presence of the old is fixed not by walls, but by a colonnade, the possibilities of architects and engineers are practically unlimited at all. It happened this time too.
Comfort concept
If we talk about an engineering solution, then the most important thing here was the formation of the most comfortable and energy efficient environment inside the building. For this, Engeх specialists had to divide all internal engineering systems into three levels, focusing on the difference in the functions of the swimming pools: a water park on the ground floor, a sports pool on the fourth - in the "canister" covering the existing building, and an eco-spa zone - on the roof. In accordance with the operating mode and features of the technical requirements, each pool must be serviced by a separate system located on the same level. This is the most important condition.
The energy modeling of the three-dimensional model of the building helped to evaluate the individual elements that form the microclimate and see the situation as a whole - it was used first to determine the thermal parameters of the entire volume, and then to create an algorithm and determine the parameters of the operation of its engineering systems and equipment.
Energy modeling of a building is not just an analysis of the parameters of individual systems, it is a very accurate determination of their operation in various temperature and climatic conditions at various functional loads. At the concept stage, this process, of course, was sufficiently generalized: the calculation was made only for the basic extreme months (in Moscow, it is February, July), and for loads during working and non-working hours. The level of solar radiation at different times of the year was taken into account, as well as the possibility and necessity of regulating the temperature inside the complex day and night. Meanwhile, despite some generalization, the goal of the designers was a high level of objectivity in the calculations, for which two recognized international thermal comfort rating indices were used. The first, PMV (Predicted Mean Vote), allows you to predict the average assessment of the comfort of the environment by visitors; the index consists of seven units, from minus three to plus three, and in this case, according to calculations, it should fluctuate within one unit around the "ideal" zero, between -0.5 and 0.5. The second index, PPD (Predicted Percentage Dissatisfied), assesses the percentage of possible dissatisfaction of water park customers, negative ratings, and, according to the authors, should not rise above 10%. The calculations, therefore, are aimed at creating a predictable and controllable environment, whose comfort turns out to be by no means random.
Effective approach
It is quite obvious that in the office part of the building and in the pool area, the approaches to creating a comfortable environment are fundamentally different. For the business part of the complex, the main characteristic of the internal microclimate is the air temperature, and the designers, accordingly, focus on the flow of people, whose presence in the room inevitably increases the temperature inside it.
A critical characteristic for rooms for "water procedures", as well as for swimming pools, is the level of air humidity: the volume of evaporation from the surface of the water depends on this. Paradoxically, the combination of these seemingly incompatible functions with a common closed power supply system allows using the heat of the heated office air in the pool premises.
At the same time, we had to reckon with the fact that the main consumer of heat in the building is the pool system itself and the heating of water for them. In the structure of a building with an open water surface, which existed since 1956, it was possible to speak simply of the release of heat into the environment. The changing rooms were separated from the outside air only by thermal curtains in the aisles, and a relatively comfortable environment in the pool area was created due to the high water temperature: plus 27-29 degrees, while the design water temperature for the new complex was 26 degrees.
For the sake of saving electricity and water supply costs, even pure condensate water formed during air cooling will be used to recharge the pool, and the heat of “gray drains” - reclaimed water from the pool - to heat the air and water inflow into it. ***
Due to the high air humidity, the main problem of swimming pools is the formation of condensation on cold surfaces of stained-glass windows and external glazing. In order to avoid this, the surface of the stained-glass window is blown with dry warm air from the air distributors built into the floor - according to the principle of the same "air curtain". And the level of ventilation air control is carried out using humidity sensors - this allows you to regulate the air flow and the operation of electric drives only depending on the basic parameter … that is, everything from the same humidity, for which, in fact, everyone strives for this blessed oasis.
In order to increase the level of comfort and not create a threat of drafts in the main rooms of the pool, as well as to redistribute and inflow air in the area where people are staying, a displacement ventilation system is used - vertical air diffusers through which air flows at a low speed. Everything - in the name of not exceeding the predicted percentage of negative ratings - the same PPD! Negative assessments, as well as negative emotions, have no place here.
Light architecture
The architectural concept of Asadov's workshop assumed a large amount of natural light: both from the overhead light, and due to the side light - through the stained-glass windows. In order to use it as efficiently as possible, some groups of lamps, most of which are located along the perimeter of the building, are smoothly controlled by light sensors and only supplement natural light. At the same time, solar collectors are built into the skylights on the roof of the existing building, collecting additional energy - due to solar radiation. This is done using a transparent ETFE film-membrane, resistant to moisture penetration and transmitting light, with photovoltaic elements applied on it, which convert direct radiation into scattered radiation. But at night, the building does not need the same temperature as during the day, and the authors proposed to smoothly reduce the heating level during non-working hours. For night activities, this descent mode can be manually overridden. In the morning - on ordinary days - the temperature in the premises is again brought to the working temperature, because the heating of the complex begins two hours before the arrival of the first visitors.
Balance of interests
Despite the significance of the object and the unconditional interest of the concept, a number of engineering solutions, nevertheless, had to be abandoned due to their high cost and inefficiency. Even the treatment of "gray waste" for reuse, which is so obvious in any pool, turned out to be too expensive. Thus, the entire engineering system as a whole was the result of a search for a reasonable balance between the level of comfort of the indoor environment, optimal use of energy and financial efficiency of the project.
