Standard concrete structures handle compression forces very well. For guaranteed compensation of tensile loads, anchoring of the reinforcement is necessary. To minimize the likelihood of corrosion of steel elements, products are placed at a distance of 2 to 7 centimeters from the outer surface. Experts call this approach a protective layer. In columnar and strip foundations, reinforcing cages, as well as floating slabs with a universal mesh, are actively used. Areas of complex modification are necessarily reinforced with separate rods.
Description
Prestressed reinforced concrete structures and other similar products are distinguished by the fact that the reinforcement tensioned to high levels is put into operation during the manufacturing process. In other cases, metal parts perceive forces from external influences. Rebar anchoring is actively used in prestressed products. Only in this case, professional builders can ensure a high degree of reliability throughout the entireoperational period. In most cases, the most effective anchoring is considered to be the one that minimizes the final cost and labor intensity of the work.
During the tension on the stops, several types of reinforcement are necessarily used:
- strong ribbed wire;
- two-strand ropes;
- hot-rolled rebar, which is in the greatest demand today.
Characteristic
Professional anchoring of reinforcement in concrete can be done in a variety of ways. Experts themselves distinguish several key varieties:
- Using various buttonholes, hooks and presser feet.
- Strong rebar protrusions (exclusively straight products).
- Using auxiliary steel products that differ in cross section.
- Universal fixtures, mounted exclusively on the ends of the rebar.
Regardless of the length of reinforcement anchoring according to SP, fixing straight elements in concrete can be used for building blanks with a periodic profile. The performer of such work needs to understand that the maximum adhesion of reinforced concrete and metal is observed only if at the initial stage the optimal strength characteristics of the solution were achieved. The reliability of fixation directly depends on whether there is transverse compression in the system.
Anchoring of reinforcement in slabs boasts optimalindicators only if the system does not provide for lateral compression. Hooks are acceptable for those construction situations where the underlying steel workpiece is absolutely smooth. The paws are mounted exclusively on rods periodic in profile.
Product parameters
To calculate the anchorage, experts use a number of mandatory indicators. Otherwise, it will be difficult to achieve the desired result. The main working parameter is the length of reinforcement anchoring in concrete. All nuances are determined with the utmost care. The final length of the seal is set by the designers with the utmost care. For these purposes, special graphics can be used. The experts took into account the class of reinforcement, as well as the resulting stress in the bar.
Used Devices
For classic bar reinforcement made of hot-rolled steel, anchors in the form of short pieces, welded washers, threaded tips (classic nuts), and embedded parts are most often used. Each item has its own specifications. If the anchor product is located at a slight angle, then a slight recess in the concrete must be provided. The protrusions will be appropriate if the overall design has no restrictions on adjacent elements and process equipment. If all these features are present, then recesses should be used.
When the anchorage of the reinforcement is located aboveconcrete surface, the product may be subject to the negative effects of corrosion. To prevent negative consequences and premature destruction of the structure, the metal mesh must be covered with a layer of concrete.
Correct calculation
To perform the anchoring of reinforcement in concrete slabs, all construction nuances must be taken into account. The calculation of the operation of sealing steel products is mastered by studying the following indicators:
- Maximum strength of reinforced concrete.
- Indicator of tension in the clutch area.
- A type of anchoring.
- Profile of reinforcement used.
- Depth and length of steel parts tab.
- Section of rods.
A simplified way to calculate important indicators (length, depth) allows craftsmen to perform all construction work with high quality in the shortest possible time. For these purposes, you can use a special table, which includes various indicators. You can study all the necessary data using a computer program. If you enter all the data, then in the end you can get a comprehensive calculation of anchoring.
Rods and cores
Experts are accustomed to anchoring those bundles that consist of 12, 18 and 24 wires. The final technology directly depends on the degree of tension of the reinforcement on the stops or concrete. If builders use double-acting hydraulic jacks, then devices in the form ofsteel plugs and blocks developed on the basis of NIIZhB.
In the process of manufacturing wedges and plugs, experts resort to heat treatment of the material, as this allows several times to increase the hardness of the steel. Modern production of sleeve and sleeve anchors is based on the use of bundles, ropes, strands. Experts place increased demands on the physical and mechanical properties of steel. For rods and cores, manufacturers use a stronger material, due to which there is no need to produce bulky products.
Assignment of fittings
Under normal operating conditions, belts and plates experience a characteristic compression at the top. The strength properties of concrete are 50 times higher than the tensile strength. Anchor reinforcement of the sole with steel bars avoids the destruction of the foundation and the subsequent opening of cracks. Due to this, the design is able to withstand much higher tensile loads. During winter swelling, the situation changes dramatically. The soil tends to push the foundation to the surface. If clay soils are supersaturated with water, then during freezing they increase in volume. The final direction of forces changes (compression at the sole, tension in the base).
