"Вестник МГСУ"

Urbanization leads to the development of megacities. Three quarters of Russians live in large cities. Negative factors of urban habitation are environmental problems: air pollution, waste production, etc. Ecological problems of large cities stimulate relocation to the suburbs. Proximity to the megacity negatively affects the territories in its area of attraction. The greatest pollution of surface waters is observed in the central and Eastern regions. The maximum levels of pollution are recorded in the rivers Moskva, Oka and Klyazma. The settlements located downstream and within the area of influence of the metropolis are deprived of the use of surface water for drinking due to strong contamination. Megapolis consumes a large amount of resources, thereby creating a deficit of resources consumed by it in the zone of its influence. Mainly, water resources are affected. A settlement located in the thirty kilometer zone around the metropolis can not fully use the scheme of water supply due to groundwater. Intensive water withdrawal for the needs of a megapolis leads to the formation of a regional depression cone with the formation of zones of gravity filtration, which is caused by a high operating load. Subject: the subject of this research is the study of water supply problems in the zone of attraction of megalopolises. Materials and methods: the method of integrated assessment and analysis of the obtained data was used. Results: the article describes the problem of providing quality drinking water to settlements in the zone of attraction of big cities. It discusses the basic schemes of water supply. The main advantages and disadvantages of each of the considered schemes are revealed. A necessity to create a single integrated method for assessing the efficiency of the water supply scheme, aimed at the efficient use of natural resources in the present environmental and economic situation, is revealed. It is shown that the described methods of water supply have different characteristics, depending on the geographical, natural and social conditions in which the settlement is located. Assessment of the applicability of a method should be carried out primarily on the basis of natural indicators, since financial indicators are derived from the natural indicators and are often subjective. As a result of the research, the megacity influence zone was identified, assessment of the current situation in the water supply field was carried out on the example of the city of Moscow and the absence of a universal system for assessing the effectiveness of water supply methods was revealed. Conclusions: an analysis of the main methods of water supply to settlements located in the zone of attraction of large cities was carried out, water supply peculiarities of such settlements are formulated, and it is shown that none of the traditional methods of water supply is universal. To select the optimal method under specific conditions, it is advisable to develop and apply the generalized natural indicators that will determine the most effective method of water supply.

Subject: the deterioration and technical condition of water supply and drainage pipelines in most of Russia’s settlements, the limitation of material resources for their restoration and renovation in conditions of housing and communal services reform, require a scientifically grounded approach to the reconstruction and modernization of these systems [1-4]. To solve these problems, the Government of the Russian Federation approved and introduced normative documents1, 2. According to them, the development of centralized water supply and water disposal systems is carried out only in accordance with the general schemes of these systems3. As part of these schemes, it is necessary to develop an electronic model of a centralized water supply and disposal system for an objective assessment of the impact of activities aimed at optimizing their work [5]. The algorithm for constructing and calibrating the electronic model of the city’s water supply system is the subject of this study. Research objectives: development of a methodology for constructing electronic models and algorithms of calibrations which are applicable to the Russian Zulu software. Materials and methods: for an objective assessment of the impact of long-term measures aimed at improving the operation of the water supply network, as well as the development of the city’s water supply system, we use modeling along with the implementation of an adequate electronic model. The adequacy of the electronic model is achieved via its calibration [6]. The object of the research is the water supply system of Minsk and Salavat in the development of electronic models for realization of their development and reconstruction directions. Results: based on the experience of implementation of a number of water supply systems (Ufa, Irkutsk, Penza, Orenburg, Tyumen, Salavat, Minsk), a methodology for constructing and calibrating electronic models was developed; the algorithms applicable to the Russian Zulu software and necessary for construction of models were also developed. Conclusions: the results of the work are implemented on a number of water supply systems in the cities of Russia and can be recommended for application of information technologies in electronic model realization, the assessment and analysis of the functioning of water supply systems and the optimization of their operation.

In the article the short historical review on the design of sanitary rooms and their configurations is given. The main errors of the recent years, which led to the decrease in accommodation convenience because of the wrong approach from both the architect and engineers, are given. It is possible to use a small useful area for sanitary facilities, but it is connected with the lack of possibility of connecting washing and dishwashers. The author considers the options of engineering equipment placement in sanitary rooms taking into account the convenience of use, safety, and also resource-saving aspect. Various solutions on the organization of heating and ventilation are provided. The possible technical solutions allowing solving a flooding problem of the first floors in elite housing estates in case of accident are offered with the help of full waterproofing of sanitary rooms, and also the whole area of the apartment. The main attention was focused on the improvements of sanitary rooms for one-room and two-room apartments, which are the most demanded in the modern market of real estate. Layout solutions of the reduced bathrooms on the placement of the necessary equipment with choice justification are provided. The attention is paid to the layout solution for modern kitchens on order to increase their comfort by the use of special two-section sinks, and also a grinder of food waste in order to allow to lower the load of the systems of rubbish disposal of a building, by dumping the crushed garbage in an internal sewer network. Various options of evolutionary development of sanitary rooms for increasing the comfort degree are given. First of all, the development should happen in the direction of not only sanitation and hygiene, but also of the maintenance of the physical health of the people living in the building. It can be carried out by increase in a useful area of sanitary rooms, installation of exercise machines, medical bathtubs and a Jacuzzi, which allows receiving good relaxation after a difficult day. Also one more direction will be the organization in occupations of an aquacycling, so-called water trainings in a special bathtub by means of exercise machines for strengthening of health of the population.

Great water losses in the internal plumbing of a building lead to the waste of money for a fence, purification and supply of water volumes in excess. This does not support the concept of water conservation and resource saving lying today in the basis of any building’s construction having plumbing. Leakage means unplanned of water losses systems in domestic water supply systems (hot or cold) as a result of impaired integrity, complicating the operation of a system and leading to high costs of repair and equipment restoration. A large number of leaks occur in old buildings, where the regulatory service life of pipelines has come to an end, and the scheduled repair for some reason has not been conducted. Steel pipelines are used in the systems without any protection from corrosion and they get out of order. Leakages in new houses are also not uncommon. They usually occur as a result of low-quality adjustment of the system by workers. It also important to note the absence of certain skills of plumbers, who don’t conduct the inspections of in-house systems in time. Sometimes also the residents themselves forget to keep their pipeline systems and water fittings in their apartment in good condition. Plumbers are not systematically invited for preventive examinations to detect possible leaks in the domestic plumbing. The amount of unproductive losses increases while simultaneous use of valve tenants, and at the increase of the number of residents in the building. Water leaks in the system depend on the amount of water system piping damages, and damages of other elements, for example, water valves, connections, etc. The pressure in the leak area also plays an important role.

In the article the main design errors of the systems of rubbish disposal over recent years are considered, in which the systems of water supply and water disposal had a supporting role. The main problems arising during operation of dry cold refuse chutes, the deprived new technical solutions on water supply and sewerage are shown. Solutions of the main task of ensuring sanitary and hygienic safety of people living in the building by installation and operation of special clearing devices with a supply of cold and hot water are provided. They allow placing the necessary equipment for cleaning an internal surface of a trunk of a refuse chute in the compact case. It will allow not only to get rid of unpleasant smells, but also will prevent distribution of rodents and insects in the whole residential building. Also this device allows fighting against obstruction of a trunk of a refuse chute large-size subjects that isn’t a rarity recently at operation of a dry cold refuse chute in a building. Much attention is paid to the organization of fire safety in case of possible fire in the collecting garbage camera that can lead to smoking of staircases and poisoning with carbon monoxide of people living in the building. The technical solutions are given, which allow to refuse using sprinkler fire extinguishing system because of its inefficient work for fire extinguishing in the collecting garbage camera. It is offered to pass to the deluge systems, allowing to extinguish a fire either automatically with the help of smoke sensor installed indoors, or by means of the controlling service personnel in the garbage container. The special attention is paid to consideration of the questions of suppression of possible ignition in a refuse chute trunk, which can occur at ejection of a burning subject in the trunk hammered with large-size garbage. As the solution to this problem it is offered to use also drencher fire extinguishing and special gas analyzers for catching of vapors of a caustic smoke, which can suddenly appear and lead to serious incidents.

In the large cities of Vietnam there is a serious problem of providing the drinking water of good quality to population and industry in the required quantity and with sufficient pressure. Chaotic building in certain areas has resulted in the formation of quite complex water systems, consisting of large main pipelines and a plurality of dead ends. Because of insufficient water pressure in the water network, the majority of consumers have to install individual reservoirs and tanks on the roofs of the buildings. The uneven water withdrawal from the network and its irrational use violates the hydraulic regime of water supply and distribution. The authors offer a water supply scheme with the accompanying transit flow lines with pipes of smaller diameter which allow providing the required amount of water and increasing the pressure on the ring. Hydraulic calculations of ring network were made using the software program WaterGEMS V8i for the worst case of the system of water supply. The plots of the water supply network show an increase in diameter of pipes is required, which greatly reduces pressure losses and ensures a reliable supply of water to the consumer. In order to solve the problem of optimal power flow, a scheme of water supply with associated main pipelines with smaller diameter was created. Laying of main pipelines accompanied by parallel lines connected to them provide better hydraulic conditions, reduce the pressure loss in the piping and shortens power consumption.

Subject: the article is devoted to the study of corrosion processes in the water supply pipeline network. Initial growth and spatial orientation of corrosive tubercle deposits in non-coated steel pipes were studied. Experimental data are presented and an analysis of conditions and mechanism of formation of corrosive tubercles in water pipes is carried out. An assumption is made about the effect of flow velocity on the formation, growth and spatial distribution of tubercle deposits on the inner surface of the pipe. Research objectives: study of the mechanism of metal pipes corrosion in the water supply systems; development and experimental verification of the hypothesis of formation of tubercle corrosion deposits in pipelines. Materials and methods: the literature data on morphology and composition of tubercle corrosion deposits is analyzed. An experimental study of the initial stage of steel pipe corrosion under static and dynamic conditions has been carried out. Shape and composition of corrosion deposits on the metal surface were analyzed with the help of scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The rate of corrosion in a steel non-coated pipe in cold tap water was measured. Results: the study of corrosion sediment shows that its formation and properties are significantly influenced by water flow rate. In the static regime, a uniform distribution of the anode and cathode areas, covered with loose sediment, is observed over the entire area of the sample. In the dynamic mode, the sediment is partially or completely removed from sample surface and the corrosion rate increases. The corrosion process proceeds with oxygen and hydrogen depolarization and contribution of hydrogen depolarization is significant. Over the anodic sections, a dense layer forms with magnetite formation during the cathodic reduction of iron hydroxides. The corrosion rate gradually decreases with time. The presence of sediment on the metal surface slows down the corrosion rate. Conclusions: the conducted studies showed that in the presence of water movement, larger anode and cathode areas are formed on non-galvanized steel pipe samples. These areas, in the course of further corrosion, are transformed into tubercles. Formation of two structural elements of future tubercle deposits was experimentally verified. Water flow velocity, along with the electrochemical processes, is a factor that directly influences the tubercle spatial arrangement and growth on the inner surface of the pipe.