BUILDING REGULATIONS
Construction heat engineering engineering heat technology Date of introduction - 01.03.2003
FOREWORD
1. DEVELOPED: NIISF Gosstroy USSR with the participation of NIIES and TsNIIpromzdanii Gosstroy USSR, TsNIIEP dwelling Gosgrazhdanstroy, TsNIIEPselstroy USSR, MISI im. VV Kuibyshev of the USSR Ministry of Higher Education, VTSNIIOT All-Union Central Council of Trade Unions, Research Institute of General and Communal Hygiene. A. N. Sysina of the Academy of Medical Sciences of the USSR, Scientific Research Institute of Mosstroy and MNIITEP of the Moscow City Executive Committee.
2. PREPARED by: KAZGOR Design Academy in connection with the revision of state standards in the field of architecture, urban planning and construction and translation into the state language.
3. SUBMITTED BY: Office of Technical Regulation and New Technologies in Construction of the Committee for Construction of the Ministry of Industry and Trade of the Republic of Kazakhstan (MIIT RK).
5. These SNiP RK are the authentic text of SNiP ІІ-3-79 * "Building heat engineering" in Russian, extended on the territory of the Republic of Kazakhstan since 1.01.1992 by letter of the RK Gosarkhstroy dated January 6, 1992, No. AK-6-20- 19 and recommended for use with * the letter of the Ministry of Construction of the Republic of Kazakhstan dated 03.03.97, No. AK-12-1-9-318 and translation into the state language.
6. REPLACE: SNiP ІІ-3-79 *.
1. General Provisions
2. Resistance to heat transfer of enclosing structures
3. Heat resistance of enclosing structures
4. Heat assimilation of the floor surface
5. Resistance to air permeability of enclosing structures
6. Resistance to vapor permeation of enclosing structures
Attachment 1*. Humidity zones of the territory of Kazakhstan and the CIS
Appendix 2. Operating conditions of enclosing structures, depending on
from the humidity conditions of rooms and humidity zones
Appendix 3 *. Thermal performance of building materials and structures
Appendix 4. Technical resistance of closed air spaces
Appendix 5 *. Schemes of heat-conducting inclusions in enclosing structures
Appendix 6 *. Reference. Reduced resistance to heat transfer of windows,
balcony doors and lanterns
Appendix 7. Coefficients of absorption of solar radiation by external material
Fencing surfaces
Appendix 8. Coefficients of heat transmission of sun protection devices
Appendix 9 *. Resistance to air permeability of materials and structures
Appendix 10 *. Excluded
Appendix 11 *. Resistance to vapor permeation of sheet materials
and thin layers of vapor barrier
Appendix 12 *. Excluded
Appendix 13 *. Reference. Thermal uniformity coefficient r
panel walls
1. General Provisions
1.1. These standards for building heat engineering must be observed when designing enclosing structures (external and interior walls, partitions, coatings, attic and intermediate floors, floors, fillings of openings: windows, lamps, doors, gates) of new and reconstructed buildings and structures for various purposes (residential, public 1, industrial and auxiliary industrial enterprises, agricultural and warehouse 2) with standardized temperature or temperature and relative humidity of the indoor air.
1.2. In order to reduce heat losses in winter and heat gains in summer, the design of buildings and structures should include:
a) space-planning solutions, taking into account the provision of the smallest area of \u200b\u200benclosing structures;
b) sun protection of skylights in accordance with the standard value of the heat transmission coefficient of sun protection devices;
c) the area of \u200b\u200blight openings in accordance with the normalized value of the coefficient of natural illumination;
d) rational use of effective thermal insulation materials;
e) Sealing of porches and folds in fillings of openings and junctions of elements (seams) in external walls and coverings.
1.3. The humidity regime of premises of buildings and structures in winter, depending on the relative humidity and temperature of the internal air, should be set according to table. one.
Table 1
1 The nomenclature of public buildings in this chapter of SNiP is adopted in accordance with the spr. 1 * to SNiP RK 3.02-02-2001.
2 Further in the text, for brevity, buildings and structures: warehouse, agricultural and industrial industrial enterprises, when the norms apply to all these buildings and structures, are combined by the term "production".
Humidity zones of the territory of Kazakhstan and the CIS should be taken according to app. one*.
The operating conditions of the enclosing structures, depending on the humidity conditions of the premises and the humidity zones of the construction area, should be established according to app. 2.
1.4. Waterproofing of walls from moistening with soil moisture should be provided (taking into account the material and structure of the walls):
horizontal - in the walls (external, internal and partitions) above the blind area of \u200b\u200ba building or structure, as well as below the level of the basement or basement floor;
vertical - the underground part of the walls, taking into account the hydrogeological conditions and the purpose of the premises.
1.5*. When designing buildings and structures, it is necessary to provide for the protection of the internal and external surfaces of the walls from the effects of moisture (industrial and household) and atmospheric precipitation (by the device of cladding or plaster, painting with waterproof compositions, etc.), taking into account the material of the walls, the conditions of their operation and the requirements of regulatory documents on design of certain types of buildings, structures and building structures.
In multilayer outer walls of industrial buildings with a humid or wet mode of premises, it is allowed to provide for the device of ventilated air layers, and with direct periodic humidification of the walls of the premises - a device for a ventilated layer with protection of the inner surface from moisture.
1.6. In the outer walls of buildings and structures with a dry or normal mode of premises, it is allowed to provide unventilated (closed) air layers and channels with a height of no more than a floor height and no more than 6 m.
1.7. Floors on the ground in rooms with a normalized internal air temperature, located above the blind area of \u200b\u200bthe building or below it by no more than 0.5 m, must be insulated in the area where the floor adjoins the outer walls 0.8 m wide by laying a layer of inorganic moisture-resistant insulation on the ground thickness determined from the condition of ensuring the thermal resistance of this layer of insulation is not less than the thermal resistance outer wall.
Laboratory work No. 1
The task: select the thickness of the insulating layer for the attic floor made of piece materials, in a residential building in Starodub. Panel construction: inner bearing layer - reinforced concrete, 120 mm, insulating layer - expanded clay gravel with density g 0\u003d 600 kg / m 3, screed - from cement-lime mortar, 40 mm. The maximum insulation thickness is 300 mm.
Determine the required reduced resistance OK to heat transfer from the conditions of energy saving:
According to SNiP 2.01.01-82 "Construction climatology and geophysics" we define for Starodub:
In accordance with the chapter of SNiP "Residential buildings", the design temperature of the internal air is assumed to be 18 ° С, since
According to the table. 1, applying interpolation, we determine the value:
for attic floors, residential buildings with GSOP \u003d 4000 ° С × day, m2 × ° С / W, and with GSOP \u003d 6000 ° С × day, m2 × ° С / W. The geometric interpretation of linear interpolation is shown in the figure. The value corresponding to the GSOP \u003d 4121 ° С × day, we calculate:
We determine the required resistance to heat transfer from sanitary and hygienic and comfortable conditions:
According to the table. 2 the coefficient n, taking into account the position of the OK in relation to the outside air, is 1.
According to the table. 3 standard temperature difference between the temperature of the internal air and the inner surface of the OK coatings and attic floors Dtн \u003d 3 ° С.
According to the table. 4 the heat transfer coefficient of the inner surface of the OK aw \u003d 8.7 W / m2 × ° С.
According to the application card, 1 humidity zone is normal. The humidity regime of the premises is normal (in accordance with the chapter of SNiP "Residential buildings" and Table 6). According to the table. 7 operating conditions OK - B.
According to Appendix 2, we take the calculated coefficients of thermal conductivity of the materials used in the design:
reinforced concrete 2500 kg / m3 - l1 \u003d 2.04 W / m × ° С;
expanded clay gravel (GOST9759-83) 600 kg / m3 - l2 \u003d 0.20 W / m × ° С;
cement-lime mortar - l3 \u003d 0.81 W / m × ° С.
In the main condition of the heat engineering calculation, we equate the right and left sides, substitute the expression for Ro and open it for the case of a three-layer OK:
We express the thickness of the insulating layer from the last equation and calculate it:
Conclusion: the thickness of the insulation layer of 0.6967 m is unrealistic for this design, since the total thickness of the attic floor will be 0.12 + 0.6967 + 0.04 \u003d 0.857 m, and the weight of the panel is 3 ´ 3 m will be at least (0.12 ´ 2500+0,697´ 600+0,04´ 1600)´ 3´ 3 \u003d 7040 kg (2500 and 1600 kg / m 3 - density of reinforced concrete and cement-lime mortar, respectively, in a dry state). Thus, the use of expanded clay gravel with a density of 600 kg / m for a warming layer 3 not possible under specified operating conditions.
Determine the required thermal conductivity coefficient of the insulation layer with a maximum thickness of 300 mm. In this case, the thickness of the insulating layer can be d 2 \u003d 0.46-0.12-0.04 \u003d 0.3 m.
To do this, we express from the general condition of the thermal engineering calculation not the thickness, but the thermal conductivity coefficient of the insulating layer:
According to Appendix 2, we determine that expanded clay gravel, used in the production of two-layer panels, has a similar thermal conductivity coefficient for expanded vermiculite (GOST 12865-67) 100 kg / m3 (l \u003d 0.08 W / m × ° С).
Conclusion: we accept the following attic floor design for operation in a residential building in Starodub: bearing layer - reinforced concrete, 120 mm, insulation layer - expanded clay gravel with a density of 100 kg / m3, 300 mm, screed - cement-lime mortar, 40 mm.
Reduced resistance to heat transfer wall panel this design is
which is more than the required resistance to heat transfer.
Laboratory work No. 2
Determination of the possibility of condensation formation on the inner surface of OK
The task: for the enclosing structure designed in example 1, check the possibility of condensation on its inner surface for two cases:
- The design does not contain heat-conducting inclusions.
- The structure has a reinforced concrete heat-conducting inclusion of type IV with dimensions a \u003d 85 mm, c \u003d 250 mm.
Initial data for the calculation:
outdoor temperature t n \u003d -31 ° FROM;
temperatures according to the August psychrometer:
dry bulb temperature (indoor air temperature) tв =21 ° FROM;
wet bulb t h \u003d 19 ° FROM.
We determine the temperature of the inner surface of the OK for a structure without heat-conducting inclusions. The total reduced resistance OK to heat transfer has already been determined in example 1: R about \u003d 4.02 m 2×° C / W. The values \u200b\u200bof the coefficients n and a in also coincide with those adopted in Example 1. By formula (11), we have
We determine the temperature of the inner surface of the OC in the region of the heat-conducting inclusion according to the formula (12).
The resistance of OK to heat transfer outside the heat-conducting inclusion coincides with the total reduced resistance of OK to heat transfer Rо:
The resistance of OK to heat transfer in the area of \u200b\u200bthe heat-conducting inclusion is determined by the formula (4) as for a heat-engineering homogeneous multilayer (three-layer) enclosure, taking into account (5), (6):
M2 × ° C / W.
To determine the coefficient h, calculate and. According to the table. 9, interpolating, we determine h \u003d 0.39.
Using the formula (12), we determine the temperature of the inner surface of the OC in the region of the heat-conducting inclusion
Determine the dew point temperature
According to the psychrometer data (tdry \u003d tv \u003d 21 ° C, tvl \u003d 19 ° C, Dt \u003d tdry-tvl \u003d 2 ° C) we determine relative humidity air using the table. eleven:
j \u003d 81%.
By internal air temperature t in =21 ° C, using the table. 12, we determine the maximum pressure of water vapor:
E \u003d 18.65 mm. rt. Art.
Using the formula (14), we determine the actual elasticity of water vapor:
mm. rt. Art.
Using the table. 12 "in reverse order", we determine: at what temperature the given value of the actual elasticity will become the maximum. As follows from the table, the value is 15.09 mm. rt. Art. the temperature corresponds to 17.6 ° C. This is the dew point temperature.
tp \u003d 17.6 ° C. insulation ceiling condensate wall
a) Since the dew point temperature is lower than the temperature of the inner surface of the OC outside the heat-conducting inclusion (tp \u003d 17.6< tв=19,51 °С), в этих местах образования конденсата при данных температурно-влажностных условиях не ожидается.
b) At the same time, in the region of the heat-conducting connection, the temperature of the inner surface of the OC is lower than the dew point temperature (tv \u003d 19.87\u003e tp \u003d 17.6 ° C). Thus, in the area of \u200b\u200bthe heat-conducting inclusion on the inner surface of the OC, condensation cannot form.
Laboratory work No. 3
The task : pick up insulation for the outer wall of a residential building in Tula. The wall is made in the form of a lightweight (well) masonry 2 bricks thick with an insulating layer.
The outer and inner layers of the masonry are brick thick. The dressing between the outer and inner layers is carried out through 6 bricks (between the sides of the walls of the wells). Ordinary clay brick based on cement-sand mortar. Tentatively take as a heater slag concrete with a density of 1200 kg / m 3... Disregard the finishing layers.
Determine the required reduced resistance of OK to heat transfer, as shown in the example of calculating a homogeneous OK.
Determine the required reduced resistance OK to heat transfer from the conditions of energy saving:
According to SNiP 2.01.01-82 "Construction climatology and geophysics" we define for the city of Tula:
In accordance with the chapter of SNiP "Residential buildings", the design temperature of the internal air is assumed to be 18 ° С.
We calculate the degree-day of the heating period:
According to the table. 1, using interpolation, we determine the value: for the walls of residential buildings with GSOP \u003d 4000 ° С × day, m2 × ° С / W, and at GSOP \u003d 6000 ° С × day, m2 × ° С / W. The geometric interpretation of linear interpolation is shown in the figure. The value corresponding to the GSOP \u003d 4513 ° С × day, we calculate:
In the further calculation, we enter the value obtained from the energy saving condition as the maximum.
Operating conditions OK (as in the same example) B.
According to Appendix 2, we take the calculated coefficients of thermal conductivity of the materials used in the design:
Ordinary clay brick based on cement-sand mortar - lkrp \u003d 0.81 W / m × ° С; slag concrete with a density of 1200 kg / m3 - ltheat \u003d 0.47 W / m × ° С;
For the calculation, we take a part of the structure that contains the wall of the "well" and half of the "well" on each side. The structure is homogeneous in height, so the calculation is carried out for a site with a height of 1 m.
With planes parallel to the direction of the heat flow, we cut the structure into 3 heat engineering homogeneous sections, of which 1 th and 3 th are multi-layered (and the same in this case), and 2 th - single layer.
We determine the thermal resistance of the sections: for a single-layer section 2 according to the formula (6):
for identical three-layer sections 1 and 3 according to the formula (5)
Determine the thermal resistance OK Rа by the formula (8). Since the calculation is carried out for a section of a structure with a height of 1 m, the areas of the sections are numerically equal to their length.
= m2 ×° C / W.
With planes perpendicular to the direction of the heat flow, we cut the structure into 3 single-layer sections (we will conventionally designate them as 4 th, 5th and 6 th), of which 4 th and 6 th are thermally homogeneous (and the same in this case), and 5 th - heterogeneous.
We calculate the thermal resistance of each section:
for heat engineering homogeneous areas according to the formula (6):
for a heterogeneous area, use the procedure used in paragraph 4:
Considering only this section, with planes parallel to the direction of the heat flow, we cut it into three homogeneous single-layer sections (5-1, 5-2 and 5-3, sections 5-1 and 5-3 are the same).
We determine the thermal resistance of each section by the formula (6):
Determine the thermal resistance of the 5th section by the formula (8):
We determine the thermal resistance of OK Rb as the sum of the resistances of individual sections:
Let us evaluate the applicability of this technique in our case.
which is less than the permissible 25%. In addition, the wall structure is flat. Thus, the calculation method is applicable in this case.
We calculate the reduced thermal resistance of the OC according to the formula (9):
We calculate the total resistance of OK to heat transfer according to the formula (7):
Conclusion: the use of expanded clay gravel with a density of 800 kg / m3 in this structure as a heater does not provide sufficient heat transfer resistance for a residential building in Moscow:
It is required to use more efficient heat-engineering materials, or to increase the thickness of the masonry, or to increase the distance between the walls of the "wells".
Literature
- SNiP II-3-79 **. Construction heat engineering / Gosstroy of the USSR. - TsITP Gosstroy USSR, 1986 .-- 32 p.
- SNiP 2.01.01-82. Construction climatology and geophysics / Gosstroy USSR. - M .: Stroyizdat, 1983 .-- 136 p.
IN Construction heat engineering data from related scientific fields (the theory of heat and mass transfer, physical chemistry, thermodynamics of irreversible processes, etc.), methods modeling and similarity theory (in particular, for engineering calculations of heat and substance transfer), which ensure the achievement of a practical effect under a variety of external conditions and different ratios of surfaces and volumes in buildings. Great importance in Construction heat engineering have full-scale and laboratory studies of temperature and humidity fields in enclosing structures buildings, as well as determination of thermophysical characteristics building materials and designs.
Methods and Conclusions Construction heat engineering are used in the design of enclosing structures, which are designed to create the necessary temperature, humidity and sanitary and hygienic conditions (taking into account the operation of heating, ventilation and air conditioning systems) in residential, public and industrial buildings. Value Construction heat engineering especially increased due to industrialization of construction, a significant increase in the scale of application (in various climatic conditions) of lightweight structures and new building materials.
The task of ensuring the required thermal properties of external enclosing structures is solved by giving them the required thermal stability and resistance to heat transfer. The admissible permeability of structures is limited by a given resistance to air permeation. The normal moisture state of structures is achieved by reducing the initial moisture content of the material and by the device moisture insulation, and in layered structures, in addition, by the expedient arrangement of structural layers made of materials with different properties.
The resistance to heat transfer must be high enough to ensure hygienically acceptable temperature conditions on the surface of the structure facing the room during the coldest period of the year. The thermal stability of structures is assessed by their ability to maintain a relative constancy of temperature in rooms with periodic fluctuations in the temperature of the air environment adjacent to the structures, and the flow of heat passing through them. The degree of thermal stability of the structure as a whole is largely determined by physical properties material from which it is made outer layer structures that perceive sharp temperature fluctuations. When calculating heat resistance, methods are used Construction heat engineeringbased on the solution of differential equations for periodically changing conditions of heat transfer. Violation of the one-dimensionality of heat transfer inside the enclosing structures in places of heat-conducting inclusions, at the joints of panels and in the corners of walls causes an undesirable decrease in temperature on the surfaces of structures facing the room, which requires a corresponding increase in their heat-shielding properties. The calculation methods in these cases are associated with the numerical solution of the differential equation of the two-dimensional temperature field ( Laplace equations ).
The temperature distribution in the building envelope also changes when cold air enters the structure. Air filtration occurs mainly through windows, joints of structures and other leaks, but to some extent through the thickness of the fences themselves. Appropriate methods have been developed for calculating changes in the temperature field at steady-state air filtration. The resistance to air permeability of all elements of the fencing must be greater than the standard values \u200b\u200bestablished Building codes and regulations.
When studying the moisture state of enclosing structures in Construction heat engineering the processes of moisture transfer occurring under the influence of the transfer potential difference are considered. Moisture transfer within the hygroscopic moisture content of materials occurs mainly due to diffusion in the vapor phase and in the adsorbed state; in this case, the transfer potential is taken to be the partial pressure of water vapor in the air filling the pores of the material. In the USSR, a graphic-analytical method for calculating the probability and amount of moisture condensing inside structures during diffusion of water vapor under steady-state conditions has become widespread. A more accurate solution for unsteady conditions can be obtained by solving the differential equations of moisture transfer, in particular, using various devices computing technology, including those using physical analogy methods (hydraulic integrators).
Lit .: Lykov A. V., Theoretical basis construction thermophysics, Minsk, 1961; Bogoslovskiy V.N., Building thermal physics, M., 1970; Fokin KF, Building heat engineering of enclosing parts of buildings, 4th ed., M., 1973; Ilyinsky V.M., Building Thermal Physics, M., 1974.
V. M. Ilyinsky.
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