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Section 11. Constructing
Section 11. Constructing
Kobeleva Svetlana Anatolevna, State university - educational-science-production complex,
Russian Federation, Orel Candidate of Technical Sciences, associate professor
E-mail: [email protected]
Environmentally benign technologies in the precast reinforced concrete housing
Abstract: The construction engineering sector and the construction technology are used the different natural resources. The choice of the most rational structural concepts and proper procedures are the main factors of resource economy. The article presents examples of resource-efficient structural systems. The evaluation of the resource-efficient structural systems should be performed by comparison with a competing project.
Keywords: environmentally benign technologies, structural systems, the paradigm ofbiosphere to compatibility.
The multistory housing construction is most popular in the Russian Federation. The large panel structures, the cast-in-place and precast construction, the modular precast building systems, the all-brick buildings are the main structural systems, which are used in the construction business [1, 210-216]. The problem of a complex assessment of potential resource-and energy saving in the civil engineering is unresolved. The natural resources consumption on the square meter of living space reaches more or less 20 ton. The rates of growth of the housebuilding is equal about 8,6 - 14,3% per year, as a result — the negative impact of industrial activity on the environment is constantly increasing.
The basic principles for the engineering of resource-efficient residential buildings are the following [2, 4-6]. The urban design principle includes building location and climatic factors, landscaping, context area, underground space and etc. The flexible structure, space zoning, compact form and other candidates are the space-planning decision principle. The selection of structural system principle contains high durability of the building materials, construction; adequate strength, stiffness of a structure, structural safety, the most rational operational cost and the like. The insolation, noise protection, sustainable building, gardens, waste reduction and etc. are the environmental performance principle. The technical principles are also important: sanitation, heating, air conditioning and building automation; instrumentation and electrical; functional housing and public utilities and others.
The problems of complex ecological safety of the construction are described in different articles [3, 468]. For example, the publications of Scherbina E.V., Kolchin M. A., Telichenko V.I. are paid to the peculiarities of the environmental assessment of construction activities. The authors have proposed a methodology for forecasting the impact of construction projects on the environment. They schematize solutions of the environmental problems of large cities on the principles of sustainable development. Moreover, the authors have offered to use green building technologies in the Russian Federation.
The Russian academy ofarchitecture and construction sciences (the doctors of technical sciences: Ilyichev V.A., Bakaeva N.V., Kolchunov V.I. and other scientists) has proposed an alternative - the paradigm of biosphere to compatibility [4, 5-8]. The authors of the paradigm have offered a calculation of the biotecnosphere humanitarian balances that allows harmoniously developing human habitats and preventing crises and catastrophes. The balance equations are derived enabling to determine the required and maximum possible quantities of conventional natural resource matter. The issue of division of technical innovation on progressive and regressive is solved according to their impact on the Biosphere. If the technologies have a negative impact on the natural environment they are regressive.
As often as not the questions of resource and energy saving got the subjects of debate in the scientific sphere [5, 74-75]. The problem of a comprehensive evaluation of potential energy efficiency and resource efficiency
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Environmentally benign technologies in the precast reinforced concrete housing
of civil buildings do not solve In the framework of this concept - the paradigm biosphere to compatibility. It is proposed to consider all life cycle stages of civil buildings: the production of natural raw materials; production of construction materials, civil structures; design; construct a building; maintenance of buildings; removal and disposal of lost property structures [6, 62-65].
The source-and-use table is required to evaluate expediency of the project, to work out the detailed project report. The method is based upon the main provisions of the following factors: natural resource endowment, effective demand, waste products and so on. There is a good reason to consider, for example, manufacturing charges (basic material, specific fuel equivalent consumption and the like), erection cost (factory labour hours, operation activity, total duration of building and etc.), working life, total operating performance and such things.
The comparison of alternatives of environmentally benign technologies should be performed with the rival design project. The common effect (ACE) can be calculated by the formulas (Eq. 1 - Eq. 2):
ACE = CE - CE (1)
i j v '
CE - the effect of the i-th measure; CE - the effect
ij
of the j-th measure.
CE = B + I (1; T) DC / (l+d)t ■> min (2)
B - budget for construction project; T- working life; DC - direct operating costs; d- discount coefficient; t-project period.
For example, in the practice of civil engineering apply constructive solutions to the building frame of the industrial panel elements (Fig. l), including load-bearing longitudinal and transverse wall panels connected to the floor slab, self-supporting outer walls. Disadvantages constructive solutions are as follows: longitudinal and transverse wall panels are made of structural concrete. Structural concrete has a high consumption of materials and energy. Slabs have a high intensity, low sound insulation performance. The intermediate j oints of exterior walls may be susceptible to freezing, as they are not insulated and should not have thermal protection. These disadvantages can be eliminated by creating and implementing new industrial energy-efficient and resource-efficient structural systems of the civil buildings on the basis of the resource cycle low-waste technologies (Fig. 2).
Figure 1. The building of the panel construction:
1 - longitudinal and transverse panel-frame; 2 -slabs; 3 - slabs with a perforated edge; 4 - girders with termo-connectors; 5 - outer self-supporting one floor wall; 6 - starter bars; 7 - in-fill concrete
Figure 2. The fragment of the constructive scheme of the building is made of frame house building: 1 - panel-frame; 2 - beam with termo-connectors; 3 - arch beam with termo-connectors; 4 - multiple-cavity reinforced concrete floor panel; 5 - wall
According to formulas 1 and 2 performed calculations for the structural systems. The results are shown in the table 1.
The second constructive solution is characterized by 30% less weight due to the use of thin-walled structural members and high-energy consumption of reinforcing steel, for example, in a horizontal elements by 10-15% (13-20 kg) per one cubic meter of concrete in the foundations by 15 - 20% (15 - 35 kg). Through the application of construction projects with lower energy
consumption, you can save about 2695 - 4831 kW-h of electricity per cubic meter of construction volume of the building throughout the life cycle [7, 4 -6]. The overage elements of energy-efficient, resource-efficient structural system after dismantling are returned into the production process as raw material for new constructions at 60-65%. Therefore, the load on municipal landfills is reducing, excluding education of illegal dumping, and storing, for example, urban parks and gardens land [8, 278-280].
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Section 11. Constructing
Accordingly, the paper presents the general methodological approaches and possible practical difficulties during the creation of environmentally benign technologies. The choice of architectural and structural
systems of a house construction are one of the significant factors, that influence on its estimated cost and resource savings through the design, construction and upkeep of buildings.
Table 1. - The results of the calculation of the different structural systems
No. The name of the structural system Material consumption of a building or structure , on one square meter of living space Charge of fuel equivalent consumption for the construction industry, on one square meter of living space The common effect, K RUR on one square meter of living space
Cement, kg Steel, ton reinforced concrete, cubic metre
1 The building of the panel construction 79.4 25.3 0.223 63.35 7.151
2 The constructive scheme of the building is made of frame house building 71.3 23.2 0.195 56.91 6.478
References:
1. Dykhovichny, U.A., Kolchunov VI. Zhilye i obshhestvennye zdanija: kratkij spravochnik inzhenera-konstruktora. Tom 2. [Residential and public buildings: a brief guide the design engineer. Volume 2 (2011) Moscow, ASV Publ., 400 p.
2. Ilyichev, V. A., Yemelyanov, S. G., Kolchunov, V.I., Bakaeva, N.V Social expectations, housing programs and quality of life on urbanized areas (2014) Industrial and Civil engineering, 2014, 2. P. 3-7.
3. Scherbina, E.V. K voprosu jekologicheskoj bezopasnosti stroitel’stva [About the problem of ecological safety of construction] (2009) Academia. Arhitektura i stroitel’stvo, 5. P. 468-469.
4. Ilyichev, V.A., Kolchunov, V.I., Karimov, A.M., Aleksashina, VV., Bakayeva, N.V., Kobeleva, S.A. The offers to the draft of the doctrine gradoustroystva and movings (strategic planning of the cities - city planning) (2012) Housing Construction, 1. P. 2-10.
5. Golenkov V.A., Kobeleva S.A. The resource-saving technologies and materials in the housing constructions (2012) Building and reconstruction, 2 (40). P. 74-78.
6. Kobeleva, S.A. The systematization and identification of the directions of quality standard of the potential of energo- and resource-saving of civil buildings (2014) Building and reconstruction, 5 (55). P. 61-66.
7. Ilyichev, V.A., Kolchunov, V.I., Kobeleva, S.A. Criterion model of the resource cycle is the basis of the ecological safety of the construction] (2014) Industrial and Civil engineering, 12. P. 3-6.
8. Kobeleva, S.A. Assessment of environmental impact of construction projects (2013) Bulletin of Civil Engineers, 3 (38). P. 277-283.
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