Coarse porous drainage concrete. TGM QUICK-MIX drainage concrete

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This type of concrete was originally in demand in regions where stone or gravel can replace expensive bricks. Large-pore variations can be used for the construction of residential and administrative buildings, here the maximum building height is 4 floors.

Also with its help it is possible to fill the frames and perform bearing walls if it is planned that the building will not experience increased loads. For more tall buildings it is permissible to use blocks from the compositions of improved brands. Please note that you can order large-pore drainage concrete in Kyiv on the carrotholding.com website, see what the specialists offer.

The main difference between draining concrete is the presence of only coarse aggregates: in this case, fine aggregates are either completely absent or reduced in volume to a minimum.

Features of the composition of large-pore concrete

The aggregate is crushed stone or gravel, the fractions of which reach a diameter of 5-50 mm, ideally it is 10-25 mm. They must comply with the standards relating to the classic composition of concrete. Also, the mixture necessarily includes slag Portland cement or Portland cement, water. Sand is not used here.

The optimal composition is determined based on the results of field studies preceding construction. Since sand is not a component of the mixture and cement is consumed in small volumes, builders can easily obtain draining concrete with large enough pores on site. Thanks to the pores, the thermal conductivity of the blocks is reduced, and their weight is minimized.

Specifics of use and basic characteristics

Manufacturers claim that such large-pore concrete is able to withstand at least 15 cycles of freezing and subsequent thawing without damage and change in structure. If the composition is used to form walls, the solution is used in tandem with a mobile formwork - the latter can be a panel metal or wooden formwork.

In cases where construction works produced in the cold season, experts recommend assembling structures from prefabricated blocks, but in principle with respect to large-pore concrete all types of "winter" work are allowed. The walls of such a mixture are necessarily covered with plaster on both sides, as they are strongly blown.

Lightweight types of large-pore concrete can be used as a filler brickwork or interior floors. IN this aspect the following components are allowed in the composition: brick crushed stone or screened slag, as binders - cement, gypsum, cement-lime mixtures.

Draining concrete can be an excellent insulator if outer cladding made of bricks, and the inner - of gypsum sheets And wooden slats. In this case, you do not have to equip the wooden formwork.

Building material advantages

The main operational advantage of the concrete in question is a larger volume of voids, when compared with the arrangement of grains in classic version. The unique structure is formed due to a special technology of combining binders and gravel. Since the composition does not provide for fine-grained aggregates, the material acquires improved physical properties. Short list of benefits:

• Enhanced stability and impressive strength - weather factors and mechanical stress are not terrible for such concrete;
• Loyal cost and simplified delivery algorithms;
• Light weight;
• Extended possibilities of application on objects under construction of various types.

Such concrete can be ordered to the site in the form of ready-made blocks, they will only have to be mounted in accordance with the project. No less common is the pouring of the solution classical methods. The choice of the optimal method depends on the design characteristics of the object.

Trays are widely used in linear (surface) drainage systems. They are the main element of the drainage system and are combined into channels. Trays are made from various materials, one of the most relevant is concrete.

Tray storm concrete - production

High-quality concrete trays are created from heavy concrete mix B30. The production process is carried out by the vibrocompression method, due to which the products have high technical characteristics.

Such concrete channels for drainage have high wear resistance and water resistance. Thanks to these qualities, the drainage channels are reliably protected from the aggressive effects of water flows and suspended particles.

In addition, concrete storm trays are reinforced with steel rod reinforcement. High-quality reinforcement can significantly increase their strength. The whole structure serves for a long time due to the treatment of reinforcement with an anti-corrosion compound.

To protect the trays from the inside, gratings are attached to them from above. Reliable concrete trays with grating are not clogged with large debris that is present in storm drains.

Concrete rain tray - design and application specifics of concrete trays

The main task of wastewater disposal is to exclude the bay and waterlogging of the territory, and drainage significantly extends the service life of structures and structures on it. High-quality concrete channels for drainage contribute to this, they are universal, as they can be used in almost all drainage systems. They also do not require repair for several years at low loads.

Concrete drain channels are also effective for protection highways from the effects of precipitation. They prevent blurring and destruction of edges asphalt pavement. Standard concrete drain pans have rectangular shape, are protected from above by a cast-iron lattice.

Applicable concrete gullies at stations Maintenance, gas stations, in industrial and production areas. They are also widely used at train stations and airports.

Concrete gutter tray - application advantages

The use of concrete channels has its advantages. High quality concrete drainage channel allows:

• provide drainage at the maximum level surface water;
• drainage to withstand high static and dynamic loads;
• increase the service life of structures and structures, for a long time avoid the need for repairs.

A high-quality concrete drainage tray with a grate has high frost resistance, provides quick maintenance and repair of drainage systems.

Drainage concrete (DBT) bearing layers are used to improve drainage. If there is no drainage of water under the road surface, a so-called “pumping effect” can occur on the bearing layer and road surface as a result of high traffic, leading to damage and defects. Washing out of the base layer material leads to the formation of voids, leading to breaks in the concrete pavement. To a greater extent, low-lying roads (low drainage points) are prone to this, where water is drained from large areas. Carrier layers of drainage concrete can be used over the entire surface or on certain dangerous sections of the road and dramatically improve the drainage situation.
Bearing layers of drainage concrete are installed under the tile flooring or paving stones. With a water-permeable surface reinforcement, the bearing layers of drainage concrete meet the requirements for high stability and sufficient infiltration of rainwater.

1. General information

drainage concrete is a concrete with large porous loose structure, containing required amount a solution with fine-grained sand, which contributes to the enveloping of the granular aggregate and the point adhesion of its components (Fig. 3). Between the grains of the aggregate, voids are formed that are not filled with a solution with fine-grained sand. In the bearing layer of drainage concrete, the content of these voids is from 15% of the volume.
The applications of drainage concrete are varied, ranging from filter pipes, drainage stones and drainage concrete bearing layers to modified drainage concrete pavements, which not only contribute to good drainage, but also to reduce traffic noise due to the high sound absorption of the large-pore loose structure. This specification covers only load-bearing layers of drained concrete laid under pavement or under tile decking and pavers.

2. Basic principles of construction

The principles for the construction of load-bearing layers of drainage concrete are presented in the specification of the Research Institute of Communications "Bear-bearing layers of drainage concrete". Features of the use of drainage concrete under permeable tile flooring and pavers are described in the specification "Permeable pavement reinforcements".

Base. Drainage concrete load-bearing layers are based on both non-bonded permeable layers, such as frost protection layers, and bonded dense layers, such as reinforcements, in which water can drain from the surface and be removed through a lateral drainage.

Design. Bearing layers of drainage concrete can be laid both over all surfaces and in separate areas at the lowest points of drainage. When laying in separate sections under roadsides at the lowest points of the slope, the thickness of the bearing layer with drainage concrete corresponds to the thickness of the adjacent bearing layer. In case of continuous laying of a bearing layer of drainage concrete, for example, under additional traffic lanes (Fig. 6), the thickness of the layer can be different.

You need to make sure that rainwater, seeping into the bearing layer with drainage concrete, is discharged through the side drainage.
Under the concrete cover, the inner edge of the bearing layer with drainage concrete in new construction must have a protrusion of at least 20 cm in relation to the longitudinal seam located above it concrete pavement(for example, between the shoulder and the traffic lane) to receive seepage water. If the drainage concrete base course and/or the adjacent base course are made by mixing on site, then the drainage concrete base course should protrude 50 cm above the joint. from drainage concrete, which allows you to create uniform support conditions and a drainage zone of 20 cm.

Table 1: Requirements for the bearing layer of drainage concrete according to the norms

When forming outer edge load-bearing layer of drainage concrete, the requirements for load-bearing layers according to ZTVT-StB apply. According to these standards, under the pavement of concrete, it is necessary to provide a bearing layer (for example, a bearing layer of drainage concrete), the width of which will be more sizes required according to the paving method used (e.g. width working surface concrete finishing machine). However, the protrusion should not be less than 35 cm. The bearing layer of drainage concrete under the paving stones:
When laying a carrier layer of drainage concrete under pavers or tile decks, the thickness of the carrier layer must comply with the requirements for carrier layers with hydraulic binders, which are defined in the directives for the standardization of the surface part of the roads. common use(RStO). As a general rule, a geotextile interlayer should be placed between the drained concrete base layer and the ballast layer of the paving stones in order to prevent the fine components of the ballast layer from penetrating into the voids of the drained concrete base layer and to ensure sufficient seepage resistance to erosion.

3. Building materials

The drainage concrete base layer must use the same binder used in the adjacent hydraulically bonded base layer. The cement must comply with DIN EN 197. Grained aggregate or minerals must pass the quality control and comply with the requirements. Recycled concrete aggregates may be used if their suitability has been proven. In the specification of work, it is necessary to indicate the possibility of using secondary building materials. Maximum size grains should not exceed 32 mm. For drainage concrete load-bearing layers, different curves are used with a discontinuous particle size distribution in the 2/4 or 4/8 mm range. Large voids require low sand content. For fractions > 8 mm, crushed granular aggregate or round-grained material can be used, while it should be taken into account that crushed material (crushed stone) increases the tensile strength in bending. In order to obtain uniformly large voids, when using coarse granular aggregate, fractions > 8 mm are subject to special requirements regarding the shape of the grains. The content of grains of elongated and flat shape (the ratio of length to thickness is more than 3: 1) should not exceed 20% by weight.

The use of additives and additives that comply with the requirements of DIN 1045 or are approved by building authorities is permitted.
Any water can be used as the addition water. natural water if it does not contain substances that prevent hardening. In case of doubt, research should be carried out. When using residual water, the provisions of the directive of the German Reinforced Concrete Committee "Concrete production using residual water, residual concrete and mortar" must be observed.

4. Building mixtures (composition, mixing)

The suitable composition of the drainage concrete base layer is determined by suitability testing. In this case, it is necessary to adhere to the requirements for the properties of the carrier layers made of drainage cover presented in table 1. Empirical data on the composition of the mixture from the specification are given in table 2.
When constructing a drainage concrete base layer, the water content data determined during suitability tests should be followed as closely as possible. The water-cement ratio, as a rule, should not exceed 0.40. Bearing layers of drainage concrete react even to a slight decrease in water content, which is reflected in their strength. When using residual concrete aggregate, the water and cement content increases (see table 2).

Table 2: Empirical data on the composition of the mixture according to

1) Higher values ​​are used for recycled concrete

The high content of cement and sand contributes to a linear increase in compressive strength, but reduces the content of voids and water permeability. While the void content decreases slightly due to the increased cement content, the increase in sand content results in a significant reduction. This should be taken into account especially when mixing on site. Fractions of grains building mix smaller than 2 mm are subject to special requirements regarding limit deviations between the content obtained during suitability tests and the actual content. The suitability test data for fractions smaller than 2 mm should not be less than 3% by weight and not more than 5% by weight. For fractions > 8 mm, requirements apply. Table 3 presents selected samples of the composition of the mixture of load-bearing layers of drainage concrete, taken from the literature.

Drainage concrete base layers can be produced in a central mixing plant or mixed on site. When mixing in a mixing plant, the mixing time after adding all the components is at least 60 s.
Mixing in place requires special soil mixer equipment. One moistening of granular mixtures is not enough, since the granulometric composition of the carrier layer of drainage concrete provides water runoff. It is recommended to supply water with a spray head over the milling shaft.

5. Execution

Laying of load-bearing layers of drainage concrete is carried out, as a rule, with the help of pavers or graders. When laying the mixture, the following points must be observed:
Laying while mixing in a central mixing plant
- before laying, ensure that the finished building mixture is protected from drying out or rain
- when laying in strips, the carrier layer of drainage concrete must be laid on the not yet hardened adjacent hydraulically bonded carrier layer, first lay the dense carrier layer, and then the carrier layer of drainage concrete
- pre-compaction with the paver bar (fig. 1 and 2)
- rolling with a smooth roller without vibration (Fig. 5)

Table 3: Examples of the composition of the mixture of load-bearing layers of drainage concrete

Laying when mixing in place
- laying a layer across the entire width in one pass. Splicing leads to uneven density and strength
- first sand and coarse grains are fed, then cement is added, water is supplied during the milling process
- the content of granular aggregate necessary to achieve the planned layer thickness and height arrangement is determined during the preliminary tests
- pressing the finished mixture with a smooth roller
- rolling with a smooth roller without vibration

Table 4: Tests for load-bearing layers of drained concrete

Combined mixing in a central mixing plant and on site The temperature of the finished building mix during installation must be > 5 °C. At air temperatures > 25 °C, the temperature of the mortar must be checked regularly. It must not exceed +30 °C.
To protect against drying, the drainage concrete base layer must be treated immediately after installation. It is advisable to cover with a water-retaining material (for example, damp jute cloth) or synthetic film. The film must be secured against shifting when exposed to wind. Aging must be carried out for at least three days. Irrigation with water is allowed only in exceptional cases. During the first 7 days after laying, the drainage concrete bearing layer must be protected from freezing temperatures.

In rainy weather, it is advisable to use concrete stabilizing admixtures during the laying of a drainage concrete base layer when mixed in a central mixing plant, which will help prevent washing off from the granular aggregate thin film building mortar. Finished drainage concrete base layer is checked by contractor construction organization profile straightness, horizontality and layer thickness (see table 4). In this case, the requirements for carrier layers in accordance with ZTVT-StB 95 apply.

notching

In a freshly laid state, longitudinal and transverse cuts must be made on the bearing layer of drainage concrete in those places where the longitudinal and transverse seams of the subsequently laid concrete coating will pass. Special attention(position and depth) should be given to the creation of longitudinal cuts in the area of ​​the inner edge of the bearing layer of drainage concrete (fig. 4a and 4b).

Bearing layer of drainage concrete under paving stones

The drainage concrete base layer under paving stones and tiling must be separated by longitudinal and transverse cuts at a distance of no more than 5 m. The coatings mentioned above should be left on the base course of the drainage pavement until the concrete pavement is laid.
If during the construction process between the laying of the bearing layer of the drainage cover and the concrete cover layer long time, there is a danger of blurring subgrade, located under the bearing layer of the drainage coating, as rainwater seeps through it.
If the laying of these layers is interrupted for a long time, appropriate measures must be taken, such as strengthening the base.

6. Tests

Tests are divided into:
- suitability tests (carried out by the contractor, confirmation of the suitability of the particle size distribution of the mixture)
- own verification control (carried out by the contractor, confirmation of properties)
- control tests
(carried out by the customer, checking the properties of the bearing layer of drainage concrete and the work performed in accordance with contractual requirements).

Route drainage concrete for the installation of permeable bonded (rigid) load-bearing bases. For pedestrian loads. For laying paving stones and slabs of natural stone.

Characteristics:

Specially selected fractions of aggregates make it possible to lay a permeable bonded carrier layer with a void content of more than 20%, which reduces the risk of destruction and fading of the road surface due to freezing of standing water;

The solution is designed to create a permeable base for paving stones and slabs of natural or ceramic stone;

Mineral composition;

Suitable for the installation of water-permeable bearing layers in areas with pedestrian traffic.

Application:

For outdoor and works;

Suitable for the installation of water-permeable bearing and sub-bases for pedestrian traffic (use category N1 ZTV Wegebau);

For laying paving stones, porcelain stoneware slabs, and natural stone.

Properties:

Dry mix of factory production;

Cement according to GOST 30515-2013

Route according to DIN 51043

Aggregates size 2-8mm according to GOST 8736-93

Contains additives to improve the properties of the solution.

Foundation preparation:

Suitable substrates for the TGM are concrete or cement screeds with a slope of 1.5-3% or a compacted base of gravel or crushed stone.

When laying the slabs on waterproof substrates, it is necessary to ensure that water is drained, for example, by means of drainage mats, gutters, etc. Water stagnation on waterproof substrates must be avoided by creating an appropriate slope. paving scheme with TGM and PFF overlays or zone (N1 according to ZTV Wegebau pedestrian zone):

Work order:

Pour 1/2 of the 40 kg bag volume into a gravity or paddle mixer with a precisely measured amount of water (2.8-3.2 l). Start stirring the mixture until it reaches a liquid consistency without lumps. Then, without stopping the rotation of the drum, gradually add the rest of the contents of the bag and continue to mix until the consistency of "wet earth". Avoid the formation of lumps of the mixture during mixing.

When laying paving stones and stone using the Fresh on Fresh technique, it is necessary to use a mortar to improve adhesion.

Natural stone slabs with heavily profiled back side can be laid on a hardened, cleaned TGM drainage concrete layer after approx. 3 days, e.g. with TNM-flex natural stone routing mortar. In this case, the penetration of the solution into the seams should not be allowed.

Thickness of the TGM layer Must be at least 40mm on a concrete base, 60mm on a compacted crushed stone base and 100mm when using mortar on sand.

Diagrams of waterproof paving systems with TGM mortar

Coating from ceramic tiles or porcelain stoneware with waterproof grout. On a permeable carrier base without the use of binders (

Ceramic tile or porcelain stoneware flooring with watertight seams on the watertight concrete slab (zone N1 according to ZTV Wegebau pedestrian zone):

Recommendations for working with drainage concrete mortar TGM quick-mix:

The thickness of the TGM sub-base in the compacted state will depend on the type of underlying substrate and expected loads, but should not be less than 40 mm when laid on concrete base and, not less than 60 mm - when laying on a crushed stone base;

When using TGM drainage concrete as a bearing layer, its thickness must be at least 100mm;

Solution pot life may vary depending on ambient temperature;

Consideration should be given to slowing down the hardening of the solution at an air temperature below 15 ° C;

Fresh solution should be protected from fast drying and protect from adverse weather conditions (scorching sun, rain, strong wind, frost, etc.) If necessary, cover the solution with a film.