CS199873B1 - Compensating porous layer if insulated concrete structures - Google Patents

Description

The invention relates to an equalizing porous layer of insulated concrete structures, in particular concrete decking, which is located below the insulations. The leveling porous layer has a leveling function and prevents separation of insulation from the substrate due to water vapor and gas pressure.

The insulation of bridge decking has so far mostly been applied to a leveling layer made of dense cement concrete. In rare cases, a leveling layer of dense bituminous concrete asphalt or closed-grain mats is also used. Under the aforementioned conditions, very often, due to the evaporation of moisture contained in the concrete, the insulation is raised from the leveling layer, or even the bituminous leveling layer is separated from the concrete structure of the deck. This problem is sometimes solved by inserting an additional layer between the leveling layer and the insulation, for example glass fiber mats, which are designed to distribute the water vapor pressure. However, the disadvantage of inserting the interlayer is the reduction of the mechanical interaction of the road construction with the deck.

These drawbacks are overcome by an equalizing porous layer of the insulated concrete structures according to the invention, especially for concrete decking. The leveling porous layer consists of a mixture of aggregate grains. The essence of the invention is that the styles of aggregate grains comprise interconnected pores and have a void space of 8 to 30% by volume. According to a second aspect of the invention, the aggregate grain mixture is unbound. According to another feature, the aggregate grain mixture is cemented with a binder, for example on a bituminous or hydraulic basis.

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The composition of the equalizing porous layer according to the invention allows the free passage of water vapors and gases away from the building and the structure, for example a bridge, and thus prevents blistering and the separation of individual gates. The composition, strength characteristics and the resulting voids of the equalizing porous layer are and are preferably determined depending on the proposed traffic load and the overall road construction. A leveling porous layer with a cemented aggregate grain mixture ensures the interconnection of individual gaps in the mixture even at higher structural stresses. The use of a leveling layer contributes considerably to the quality of the building and positively affects its service life.

An exemplary embodiment of an equalizing porous layer according to the invention is schematically shown in the accompanying drawing where a cross-sectional view of a pavement structure on a concrete deck with equalizing porous layer.

Example 1

A leveling porous layer for lightly loaded structures, preferably a concrete footbridge, is made of an unbound mixture of aggregate grains. The aggregate mixture of the equalizing porous gate 1 consists of a mined 0/8 mm gravel sand. The void volume of the mixture is 25% by volume.

Example 2

The equalizing porous layer (Fig. 1) for a heavy traffic load of 200 to 400 design vehicles per 24 hours was made of a cement-bonded cement-based mixture. The mixture contains 55% by weight of crushed aggregate fraction 4/8 mm, 35% by weight. Crushed aggregate fraction 0/4 mm, 5 wt. % limestone meal and 5 wt. oil road asphalt. The void content of the mixture is 12% by volume of aggregate. The equalizing porous layer 1 is supplemented by commonly used systems for the removal of vapor and gas pressure, possibly water, outside the bridge structure. The leveling porous layer 1 is laid on the surface of the deck structure 2. On the leveling porous layer is insulated 6 and other road construction layers

Example 3

The compensating porous layer for a semi-heavy traffic load of 75 to 200 design vehicles in 24 hours consists of a mixture of aggregate grains, cemented on a hydraulic basis, in this case cement. The mixture consists of 50 wt. mined aggregate fraction 8/16, 50 wt. aggregates fraction 4/8 cement-bonded, weighing 120 kg / m ³ . The void content of the mixture is 28% by volume.

The equalizing porous layer 1 can also be used advantageously on other insulated constructions, especially where undesirable peeling of the insulation due to water vapor pressure and plans could occur.

Claims (3)

SUBJECT OF THE INVENTION 1. An equalizing porous layer of insulated concrete structures, in particular concrete decking, consisting of a mixture of aggregate grains, characterized in that the aggregate grain mixture contains interconnected pores and has a gap of 8 to 30% by volume. 2. A leveling porous layer according to claim 1, characterized in that the ammonium grains are unbonded 199 873 3. A compensating porous layer according to claim 1, characterized in that the aggregate grains are cemented with a binder, for example on a bituminous or hydraulic basis.