One of the most necessary, inexpensive and easy-to-install building materials are floor slabs. Currently, two types of such products are produced: hollow and full-bodied. Each type is designed to solve certain construction problems, but still, most often, hollow-core floor slabs are used in the construction of various structures. In fact, these are universal structures, since they can be used to build any type. They are indispensable for building floors, separating basements from main buildings, building garages, roofs and many other structures.
Hollow-core floor slab (PC) is a flat rectangular concrete block. Inside the structure there are oval cavities. They are needed to reduce the weight of the panel, increase its heat-preserving properties. If necessary, engineering communications can be laid inside the voids.
Production Features
Production of panels takes place according to design drawingsby pouring according to the requirements of GOST: multi-hollow floor slabs are made of heavy concrete, the density class of which is not less than B30. To provide the products with the necessary strength, a frame is placed in the formwork. To extend the service life and maintain strength, all metal elements are coated with a special composition to protect against corrosion. As a result, products retain good flexural strength for many decades.
In addition, according to GOST, for panels that will rest on walls with only two or three sides, a frame is made not from simple reinforcement, but prestressed.
In order to further facilitate the work with finishing materials, the upper and lower planes of the panels are carefully aligned, so that they can be painted, wallpapered, and other types of finishing materials used without plastering. Slinging holes and embedded loops on the panels are designed for easy installation and movement.
Production method
The entire production process is strictly controlled and regulated in accordance with the requirements of official documents. Products are manufactured according to the following scheme: a frame structure is mounted in a special open-type mold 3-5 cm from the edge.
Sling loops are laid along with the frame. When the metal reinforcement is ready, the mixture with concrete is poured. Thanks to the use of the vibration method, the products are not only durable, high-strength, but also strictly comply with the design indicators. They have no flowcracks, cavities, chips and other defects that may reduce the strength of the product.
Panels are then heat-treated and sent to a laboratory where they undergo proof tests for flaws, performance and benchmarks.
Materials
In order for hollow-core floor slabs to have the necessary characteristics in the future, for their manufacture, in addition to purified water, manufacturers use only high-quality Portland cements. The filler is fine sand and crushed gravel. They are resistant to temperature extremes and give these properties to the panel. Various plasticizers are used to maximize other important indicators.
For continuous reinforcement, depending on the purpose of the products, can be used:
- Seven-wire strands with a section of 6P-7.
- High-strength wire of a periodic profile. Its cross section should be 5Vr-II.
- Rods made with heat-hardened At-V grade steel.
- Ropes with a diameter of 6 mm class K-7.
- Bp-II class reinforcing wire and other similar materials permitted by the State Standard.
Standard indicators
Hollowcore slabs series 1 141 1 is the main standard for the manufacture of PC panels. Therefore, all regulations and rules are strictly observed during production. Moreover, the panels neverthey are sent for sale if they have not passed the quality check, as evidenced by the technical passports and certificates issued to them.
Mandatory marking is applied to the side faces of each panel, displaying all information about the product. Based on the applied data, the selection of elements for a particular object is carried out, taking into account the characteristics of panel products and the requirements for their characteristics.
Marking
Since hollow core slabs are intended for standard construction, they are marked during manufacture. To do this, signs are applied in the form of letters and numbers:
- PC – hollow core slab.
- The first number is the length. Shown in decimeters (rounded to the nearest whole number).
- The second digit indicates the width in dm (value rounded).
- The third digit indicates the maximum bearing properties of the product. The indicator is shown in MPa.
Features
At present, many types of hollow core products are produced, which differ in the diameter of the voids and the shape of the slabs themselves. One of the indicators by which hollow-core floor slabs differ is the size.
| Slab Type | Thickness in centimeters | Product length in meters | Concrete density, average in kg per 1 m/3 |
| 1PK, 1PKT, 1PKK | 12 | Up to 7, 2 | 1 400 – 2500 |
| 1pc | 12 | Up to 9, 0 | 1 400 - 2 5 00 |
| 2PK, 2PKT, 2PKK | 16 | Up to 7, 2 | 2 200 – 2 500 |
| 3PK, 3PKT, 3PKK | 16 | Up to 6, 3 | 2 200 – 2 500 |
| 4pcs | 16 | Up to 9, 0 | 1 400 – 2 500 |
| 5pcs | 17 | Up to 12, 0 | 2 200 – 2 500 |
| 6pcs | 15 | Up to 12, 0 | 2 200 – 2 500 |
| 7pcs | 9 | Up to 7, 2 | 2 200 – 2 500 |
| PG | 15 | Up to 12, 0 | 2 200 – 2 500 |
Panels can be used on structures of any mounting dimensions: overall dimensions are so unified that they fit everywhere. This is one of the important characteristics of the products that this series represents. Hollow-core floor slabs can withstand significant loads, they are inferior in size to similar products that are intended for use in the construction of foundations, load-bearing walls. But at the same time, panel structures with voids have a multiple margin of safety.
Basic Features
To understand how important and necessary panel structures are for construction, it is enough to study the advantages that reinforced concrete multi-hollow floor slabs have. Series 1 141 1 is designed for use in areas with high seismicity, therefore it is particularly durable. In addition, the use of products has many other positive qualities:
- Allow structures to withstand quite impressive loads.
- Hollow products provide high thermal insulation properties, excellent frost resistance and fire safety.
- With the correct adjustment of the supports, the floor slabs provide an absolute horizontal surface.
- To increase frost resistance, panels are produced in which the cavities are filled with porous insulation materials.
- The canvases are durable, do not need additional care, their use significantly facilitates the application of the finish coat.
- The use of slabs improves the watertightness of a building by preventing gas, steam, and noise from penetrating other parts of buildings.
Application features
PC panels are in demand today in the construction of facilities for various purposes. These are industrial and public buildings, residential buildings, loggias, balconies. Using multi-hollow slabs, you can create two structural elements at once. As suchare the ceiling and the floor, which will also be almost perfectly flat.
Due to characteristics such as strength, fire resistance, thermal insulation, panels can be used in the construction of building structures in areas with any climate.
