RU2304203C1 - Vented building block and radon-protective system for building using above building blocks - Google Patents

Abstract

FIELD: construction, particularly means to protect building against radon and other ground gases, for instance multilayered building blocks used for radon-protective foundation base and wall panel production.

SUBSTANCE: vented building block comprises box member and porous filler arranged on box member bottom. The filler has air-discharge orifices. The box is monolithic and is formed of concrete material mainly based on rigid cement mixes. Box interior is filled with porous filler. Two one-way valve assemblies are built in main box face layer so that the valve assemblies permit air passage inside the box provided with porous filler. One one-way valve assembly opens valves in the case of increased ambient air pressure, another one opens valves in the case of decreased ambient air pressure. Radon-protective system is also disclosed.

EFFECT: provision of load-bearing capabilities and ground gas discharge from basement into atmosphere.

7 cl, 4 dwg

Description

The invention relates to systems for protecting the air of a building from radon and other ground gases and can be used in construction, in particular in the production of multilayer building blocks for the manufacture of anti-radon base plates and foundation walls of buildings.

According to aerial surveys, the presence of local areas with a relatively high content of radium in the soil, and with a relatively low content, was revealed. (Radium-226 is a natural radionuclide from which radon is directly formed).

The basic principle of anti-radon protection is to prevent radon from entering the premises, which can be realized by depressing the soil base of the floor using a radon collector and exhaust ventilation system, sealing gaps, seams, joints and communication openings, etc. Carrying out radon-protective measures at the design and construction stages is more effective and less expensive than in an already constructed building.

Carrying out radon-protective measures by ensuring through ventilation of basements significantly reduces the concentration of radon in the building.

The sanitary rules (SP 2.6.1.799-99 clause 7.1.2.) Prescribe that for the construction of industrial buildings it is necessary to choose areas where the density of radon flux from the soil surface does not exceed 250 mBq / (m ² × s). When designing the construction of a building on a site with a radon flux density from the soil surface of more than 250 mBq / (m ² × s), a radon protection system should be presented in the building design. The normative equivalent equilibrium volumetric activity (EERA) for residential premises is 200 Bq / m ³ .

During construction in radon-hazardous areas, preventive radon-shielding measures are provided that will minimize the risk of excessive concentrations of radon in the premises of the building.

Known technical solutions from the Guide “Designing anti-radon protection of residential and public buildings to MGSN 2.02-97. Allowable levels of ionizing radiation and radon in building plots ”, approved by the Moscow Government by Decree No. 57 of February 4, 1997, in which one of the ways is proposed to use the possibility of reducing the concentration of radon in indoor air due to their ventilation with outside air. Outside ventilation is limited by the maximum permissible (or economically viable) value of the air exchange rate. Therefore, ventilation should only be considered as an adjunct to complement other solutions. Intensification of ventilation leads to an increase in energy costs for heating the building.

In the case of a columnar foundation, with a completely open underground space and the absence of radon emissions from the building envelope, the activity of radon in the premises of the first floor does not exceed its activity in the outside air. The necessary air exchange in the underground is ensured if its height from the ground level is at least 0.7 m. However, this solution cannot be widely used due to the loss of usable space in the building volume and the need for a significant increase in the thermal resistance of the lower floor. To ensure moderate natural through ventilation of closed underground floors and unheated basements, it is recommended to install ventilation openings in the basement on all facades of the building with a total opening area of 1 to 1.5% of the basement area.

When using the forced ventilation system, it is not allowed that during its operation the pressure in the room is lower than in the basement or underground. Excessive pressure in the premises prevents the penetration of radon into them through the basement, however, at the same time, the humidity regime of all building envelopes deteriorates. The optimal is a well-balanced system of supply and exhaust ventilation, providing the required for hygienic reasons the rate of air exchange in the rooms and the minimum pressure difference between the basement and the upper rooms.

Known technical solution (analog) described by L. Gulabyants in the manual "Design of anti-radon protection of residential and public buildings" / approved. Moskomarchitecture dated February 20, 1998, No. 7, which provides the highest anti-radon protection effect of the building, which is achieved with depression (creating a zone of low pressure) of the basement of the basement floor. Depression is provided when the radon collector is supplemented with a special forced exhaust ventilation system, completely unrelated to room ventilation.

When using forced extraction, the effective operation of the protection system is ensured by installing one underground pipe per 100-120 m ^{2 of} protected area and using a low-pressure fan with a capacity of 150 to 250 m ³ / h. Fans should have a sealed enclosure and be located in the vertical part of the pipes as close as possible to the point of emission of soil gas into the atmosphere.

Fan mounting is recommended using removable fasteners and flexible tight connection of the casing with the pipe. Installation of fans in the basement and other rooms of the building, except for the attic, is not allowed.

To control the operation of the fan, it is recommended to install two switches. One is installed in a place convenient for the user, the second - in close proximity to the fan to exclude the possibility of its inclusion in the repair or maintenance work.

To monitor the condition and efficiency of the exhaust ventilation system, pressure sensors installed on the pipes, as well as alarm devices, can be used.

The disadvantage of this analogue is that it requires a fan with an appropriate drive and energy costs, and also requires special devices to control the operation of the fan, as well as to monitor the condition and efficiency of the exhaust ventilation system, which significantly complicates the design.

A technical solution is known (the closest analogue is a prototype of a ventilated building block) - see patent No. 2208102 “Concrete building block”, Е04С 1/40, dated 2001.12.17, which describes a concrete building block including a face layer, concrete building layers and located between them a porous insulating layer, while the front layer is made of a mixture of cement, expanded clay, sand and water.

The disadvantage of this prototype according to patent No. 2208102 is that the multilayer concrete block practically does not remove the air coming from the basement or underground into the porous layer and further into the atmosphere, since filtering the air flow through the porous layer of the concrete building block with chaotic drops in air pressure on opposite surfaces of the block, not properly organized. A portion of air contaminated with radon, without going through the entire layer of porous material, can change the direction of its movement in the porous layer to the opposite one due to the random nature of pressure drops on opposite surfaces of the block and will enter the underground or basement space of the room, and not out into the atmosphere.

Typically, the known structural elements of the building foundation of a building can withstand loads and resist the transfer of heat and moisture through the foundation wall or the basement slab.

The objective of the present invention is to provide a ventilated building block, which, as an element of the supporting structure of the foundation, can be used in the manufacture of slabs to cover the soil of the base or foundation wall, having the properties of devices designed to discharge ground gases and polluted air into the basement or underground without using an external source of energy.

The technical effect is to increase the reliability and efficiency of the radon protection of the building by using unidirectional valve devices and a sealed chamber as a device that traps ground gases and organizes unidirectional movement of air trapping these gases through a porous material. The created device has a new set of features, providing the ability to respond to fluctuations in air temperature and atmospheric pressure to achieve the technical effect of the invention.

The technical effect is achieved by the fact that the ventilated building block used in the construction of the foundation wall and / or foundation slabs of the foundation foundation contains a monolithic duct with the main, side and rear faces of concrete based on predominantly hard cement mortars with porous filler placed in the duct cavity, for example, with open-porous concrete, two unidirectional valve devices are mounted in the layer of the main face of the duct with the possibility of passing air into the cavity of the duct with porous filling Itel, one with the ability to open valves at high air pressure outside the unit and the second with the ability to open valves at low air pressure outside the unit.

The ventilated building block, in order to be able to flush the porous filler with liquid, has two channel openings in the layer of opposite side walls of the box, ending with fittings with valves on the main face of the box and communicating with the cavity in which the porous filler is placed.

A technical solution is known (the closest analogue of the radon protection system) - a radon protection system with a camera for collecting radon (see the manual "Designing anti-radon protection of residential and public buildings", author - prof., Doctor of Technical Sciences L. Gulabyants / Approved by the instruction of the Moscow City Architecture Committee dated February 20, 1998, No. 7), which is an airtight chamber mounted on a sand and gravel bedding above the ground in underground, consisting of vertical walls, a main plate and an air duct in the form of a pipe communicating with the atmosphere. It is recommended that the walls of the chamber be folded out of bricks without the use of a solution so that in each row between the ends of the bricks there are slots 40-50 mm wide. When installing the internal risers, a stronger natural draft will be created and for this reason they are preferable to external ones, however, their tightness must be ensured in order to prevent the penetration of radon from the risers into the premises. The sections of risers passing through the attic are recommended to be insulated. The efficient operation of the radon collector with natural extraction is ensured when the pressure difference in the gravel layer and at the outlet of the riser is at least 3-5 Pa.

A disadvantage of the known radon protection according to the prototype, the technical solution of the design of the system with a camera for collecting radon, is that, firstly, not the entire surface of the underground can be effectively protected by a system with cameras of this design, secondly, the suction of air through the walls of the chamber and sand and gravel bedding can be difficult due to waterlogging by groundwater, and thirdly, in case of unfavorable airflows in the atmosphere, air contaminated with radon can move not into the atmosphere, but into the underground and then into the room.

The objective of the present invention is to provide a radon protection system using ventilated and flushed building blocks proposed by the authors, which has increased reliability and efficiency compared to the known similar system of devices designed to remove ground gases from under a building, as well as basement air or underground contaminated radon, without using an external energy source, but only due to periodic fluctuations in atmospheric pressure, constantly occurring x over time and the natural draft in the riser, the offtake gases to the roof.

The technical effect is achieved in that the anti-radar protection system of the building, containing a slab covering the basement or underground, and installed on the ground boxes with holes and pipes for the possibility of communication boxes with a vertical duct having an exit on the roof of the building, characterized in that the plate and boxes made at the same time in the form of a coating on the entire surface of the soil of the base of ventilated building blocks, the suture spaces between the blocks are filled with mortar, while the surface of the blocks and suture spans fabrics are impregnated with a sealing compound.

The anti-radon protection system of the building has a coating laid on the foundation ground in the form of a floor plate.

The anti-radon protection system of a building may have a coating laid in the form of a foundation wall in the ground facing the main surface of the blocks inside the basement.

The anti-radon protection system of the building can be used as a sealing compound by Silor.

The anti-radon protection system of the building can have a vertical duct in the upper part, which is equipped with a deflector and the anti-radon protection activation system of the building, which includes an air flow sensor and a fan with a timer for the on-time.

Impregnation for concrete "Silor" was developed under the guidance of Professor R.A. Veselovsky. The coating is a one-component liquid, resembling kerosene in viscosity and appearance. When applied to the surface of concrete, the impregnation penetrates into its pores and chemically interacts with materials located on the surface of the pores. This interaction leads to the formation of a new composite material, durable, sealed, chemically resistant. The curing time of the impregnation in the pores of concrete is 6-10 hours. To protect concrete from biological corrosion, bactericidal and fungicidal properties are given to it. Cured impregnation for concrete is non-flammable and non-toxic.

Figure 1 and Figure 2 shows a ventilated building block with the main structural elements, where indicated:

(1) - a monolithic duct of a ventilated building block with the main, side and rear faces of concrete;

(2) and (3) - inlet and outlet openings on the main face of the ventilated building block. To the outlet (3) it is possible to connect a chimney (chimney conventionally not shown);

(4) and (5) - technological holes with fittings and valves (or plugs) blocking the channels, channels (4) and (5) communicate the porous filler location cavity and the outer surface on the main face of the block;

(6) - concrete layer based on predominantly hard cement mortars;

(7) - a porous filler, which is placed in the cavity of the box;

(8) - a chamber equipped with a unidirectional valve device with the ability to open valves at high air pressure outside the unit;

(9) - a chamber equipped with a unidirectional valve device with the ability to open valves with reduced air pressure outside the unit;

(10) - an inlet unidirectional valve device with a valve opening a channel for the passage of air from the underground or basement into the cavity of a ventilated building block with increased air pressure from the outside relative to the air pressure inside the block;

(11) - unidirectional valve output device with a valve opening a channel for passage of air contaminated with ground gases into the exhaust pipe at reduced air pressure in the exhaust pipe relative to the pressure inside the unit;

Figure 3 and Figure 4 shows fragments of variants of the anti-radar protection system of a building, respectively, for horizontal and vertical location of the ground cover, using ventilated building blocks, where it is indicated:

(1), (2), (3), (4) and (5) are the same structural elements of ventilated building blocks as in FIG. and Figure 2, the filling of the joints with cement-sand mortar between the blocks (1) is conditionally not shown;

(12) - multiblock air duct;

(13) - a collector receiving air from multi-unit ducts;

(14) - a vertical duct ending in the upper part with a deflector (not shown in the figure);

(W) - air entering the ventilated unit;

(WR) - air leaving the ventilated unit.

Figure 3 and Figure 4 are conventionally marked with a line of soil deepening (Z) and the foundation elements of the building and the entire building with a basement or underground, from where the discharge of ground gases occurs, are not shown.

Works ventilated building block as follows.

When air pressure fluctuates outside the unit (1), a unidirectional air flow (W) occurs through the holes (2) and (3) on the surface of the main face of the ventilated building block (1). When the pressure outside the unit (1) increases, air (W) through the hole (2) overcomes the resistance to opening the unidirectional valve (10) and enters the chamber cavity (7) until the values of the pressure outside the block and the pressure in the chamber cavity are equal ( 7). In this case, the valve (11) remains closed and prevents air from entering the chamber cavity (7) through the hole (3). When pressure decreases outside the unit (1), air through the hole (3) overcomes the resistance to opening the unidirectional valve (11) and leaves the chamber cavity (7) until the pressure values outside the block and the pressure in the chamber cavity (7) are equal. In this case, the valve (10) remains closed and prevents the exit of contaminated air (WR) from the cavity of the chamber (7) through the hole (2). Thus, when the air pressure fluctuates outside the unit (1), a unidirectional flow of its movement occurs, that is, through the hole (2), air (W) exclusively enters the ventilated unit (1), and through the hole (3) air (WR) exclusively leaves from the ventilated unit (1).

During operation of the ventilated building block, it may cease to function in the air ventilation mode due to the fact that the pores of the porous filler are completely clogged with dust or moisture if they somehow end up in a basement or underground. In this case, to regenerate the porous filler and restore its ventilating properties, the cavity filled with the filler is washed with special detergents through channels (4) and (5), which have fittings for connecting hoses with running water or with a flushing composition. In this regeneration process, the indicated valves of the channels (4) and (5) must be open, and after washing and drying with compressed air, the indicated valves of the channels (4) and (5) must be closed. The gates of the channels (4) and (5) can be used to periodically remove condensate formed in the cavity of the unit, or to constantly flush and forcefully drain groundwater saturated with radon into the basement or underground.

Using the same technological fittings with channel valves (4) and (5), which are locked during normal operation of the unit, it is possible to release moisture and dry the unit from the inside with compressed air.

During technological operations, the valve devices (10) and (11) in the channels of the holes (2) and (3) can be locked in the locked state.

The anti-radon protection system works using ventilated building blocks as follows.

The action of the proposed anti-radon protection system using ventilated building blocks is based, firstly, on the use of convection air draft in a vertical duct (14,) see Figure 3, secondly, on the use of atmospheric air pressure fluctuations occurring outside the building, and also, thirdly, on the use of air pressure differences in the basement or underground due to, for example, the inclusion of forced ventilation or opening the front door or hatch, which are usually equipped with basements and underground I am. In this case, increased resistance of the units and elements of the building envelope (appropriate impregnation and sticker of gas-tight materials) to the diffusion and convective transfer of radon from the source to the premises should be provided. The advantage of the proposed passive system is that it does not require energy supply during operation.

Air (W) in the direction of the arrows (see Figure 3) from the ventilated room of the basement or underground (structural elements of the basement or underground are not shown) through the holes (2) in the main faces of the blocks enters the blocks (1) and mixes with ground gases, caught in the camera blocks (1). Further, through the holes (3) in the main face of the blocks (1) equipped with nozzles for connecting to the horizontal duct (12), air enters the manifold (13) that receives air from the ducts (12), and then through the vertical duct (14) the air ( WR), contaminated with radon and other ground gases, is released into the atmosphere. Each of the ducts (12) is a collector for all units (1) located nearby. All ventilated blocks (1) have a connection through the nozzle holes (3) to the ducts (12).

The operation of the anti-radon system may stop in the event of a prolonged absence of fluctuations in atmospheric air pressure and a prolonged absence of temperature differences coinciding with this period, causing convective air draft in the system. Such a coincidence of atmospheric phenomena is almost unlikely, however, for such a case, it is possible to activate the anti-radon protection of the building due to the installed fan in the vertical duct (14). Even less likely is the coincidence of undesirable variations in pressure and air temperature in the atmosphere outside the building and inside the basement, when convective draft and pressure drop would cause the reverse movement of air through the air ducts from the atmosphere outside the building into the basement or underground. However, in this case, the ingress of air contaminated with ground gases into the basement or underground is completely ruled out, thanks to the unidirectional valves installed in the blocks.

The anti-radon protection system of a building using the proposed design of ventilated building blocks can be both passive and active. In order for the system to be active during periods of undesirable coincidence of pressure and air temperature in the atmosphere outside the building and inside the basement, it must be additionally equipped with a fan installed at the end of the vertical duct, as well as an air flow sensor through the vertical duct. After a certain specified pause value in the air flow, the flow sensor must turn on the fan for a certain specified time of the system in activation mode.

The system’s action in the activation mode is based on reducing the radon load on the building by forcibly draining radon from the source into the atmosphere. According to modern estimates, the territory of the Moscow region is classified as moderately radon-hazardous. In such conditions, in most practical cases, to ensure the required protection of buildings, it is sufficient to use the protection systems of the proposed design.

References

1. Permissible levels of ionizing radiation and radon in building sites. Approved by the Government of Moscow dated February 4, 1997 No. 57.

2. Design of anti-radon protection of residential and public buildings. Benefit to MGSN 2.02-97. It is approved by the instruction of the Moscow City Architecture Committee dated February 20, 1998 No. 7.

Claims (7)

1. A ventilated building block used in the construction of the foundation wall and / or foundation slabs, containing a box with faces and a porous filler placed at the bottom of the box, having openings for the possibility of air exhaust, characterized in that the box is made of monolithic concrete based on predominantly hard cement mortars, inside the box is filled with porous filler, for example open-porous concrete, two unidirectional valve devices are mounted in the layer of the main face of the box the possibility of passage of air in a box cavity with a porous filler, one - with the possibility of opening the valves at an elevated air pressure outside the unit and a second - with the possibility of opening the valves at a reduced pressure of air outside the block. 2. The ventilated building block according to claim 1, characterized in that for the possibility of washing the liquid with a porous filler, there are two channel openings in the layer of opposite side walls of the duct, ending with fittings with valves on the main face of the duct and communicating with the cavity in which the porous filler is placed. 3. The anti-radon protection system of the building, containing a slab covering the basement or underground, and installed on the ground box with holes and pipes, for the possibility of communicating the cavities of the box with a vertical duct having an exit on the roof of the building, characterized in that the plate and box are made at the same time in the form of a coating on the entire surface of the soil of the base of the ventilated building blocks according to claim 1, the suture spaces between the blocks are filled with solution, while the surface of the blocks and suture gaps are impregnated uyuschim composition. 4. The anti-radon protection system of a building according to claim 3, characterized in that the coating is laid on the base soil in the form of a floor plate. 5. The anti-radar protection system of a building according to claim 3, characterized in that the coating is laid in the form of a foundation wall in the soil facing the main surface of the blocks according to claim 1 inside the basement. 6. The anti-radon protection system of a building according to claim 3, characterized in that "Silor" is used as the sealing composition. 7. The anti-radon protection system of a building according to claim 3, characterized in that the vertical duct in the upper part is equipped with a deflector and an anti-radon protection activation system of the building, which includes an air flow sensor and a fan with a timer for the on-time.

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