These samples, along with slabs of monolithic( less often, wooden) are widely used in the construction industry. As a rule, hollow plates serve for the arrangement of floors( including interfloor), open areas with a load of not more than 800 kg / m2.Manufacturing technology involves the use of concretes in the main classes of B15 and B20 grades of 200 or 250.
The industry produces several varieties of hollow core slabs, some of which are clear to one another only from specialists. Therefore, we only indicate that they can be relaxed and prestressed, with different types of reinforcement. There is a difference in characteristics, for example, parameters of bars( from A-III to A-V).
As a rule, the slab sizes have a certain range( in "m"):
- length - from 3 to 9;
- width - from 1,2 to 1,5;
- thickness - from 0,2 to 0,4.
Designation of products
- PB - multi-empty.
- PC - with round channels.
The number before the letters indicates the diameter of the holes in "mm".1K - 159, 2K - 140.
Numbers behind letters characterize linear parameters( length, width, thickness in "dm").For example, PC 24-10-8.
The reinforcement material can be referred to below. For the same product it looks like this - PC 24-10-8 AVT( "T" means concrete is heavy).
- H - reinforcement of the lower plane.
- In the upper.
- NEC - from below, from above and between cavities.
There are a number of other abbreviations used for integrated reinforcement. Their decoding is given by the manufacturer. For example, НВКУ, 4НВК, which means one- or multi-row reinforcement with a rod. The letter "U" indicates an increased strength( for example, application in the production of concrete B45).
Weight
Due to the fact that it is smaller than for monolithic analogue slabs, it is easy to lift products to a height. In addition, the workload that they create on the foundation of the building is reduced, which is important in individual construction, and the house will be cheaper.
Performance characteristics
The presence of cavities in the mass of concrete provides higher properties of products for sound insulation and lowering the level of heat loss. In addition, such a constructive feature increases the strength of the products in bending.
Such plates are also convenient because the existing "channels" can be used for laying utilities( for example, electrical wiring).
The cost of
As in the manufacture of similar samples the consumption of materials on the hollow slab is lower than that for monolithic slab, then it costs less, on average, by ¼.
Given the huge range of products, it is advisable to quote only the marginal prices for 1 product( minimum and maximum).So, the cooker PC24-10-8 costs about 2,200 rubles, and the PC 90-15-8 - 18,990 rubles.
Disadvantages of
- Additional precautions must be taken when transporting floor slabs. Despite its massive nature, in fact, these products are quite easily destroyed. Therefore, between them, along the perimeter, you need to lay boards or bars.
- Given the specifics of these products, their use is somewhat limited. For example, it is not possible to use observation platforms( with a perimeter erection), balconies and in a number of other cases.
If the products are produced under a specific order, then its characteristics may be very different from those mentioned above. For example, increased load( up to 1,200 kg / m²), changed linear dimensions. This allows you to lay products where normal, standard, can not be used.
