Table of Contents
Floor slabs represent horizontally located panels installed between floors. Interfloor plates at private construction of cottages are used, for multi-storey building and also for construction of buildings of industrial function. Today it is possible to get practically any sizes of floor slabs, but standard products will cost considerably cheaper. The main condition upon purchase – is correct to choose type and the number of panels.
That concrete slabs represent: price of the main types of products
Any construction does not do without use of steel concrete overlappings which help to accelerate construction construction considerably. The different sizes reinforced concrete slabs of overlapping are used for separation of the first floor from upper. The main task of products – to provide rigid construction of the building. All plates differ in rectangular shape, are made of different types of concrete, and the additional rigidity to panels is provided by the metal gauze and reinforcing wire.
Thanks to wide choice of types and the sizes of floor slabs have the broad range of use. Designs are applied to forming of the base of construction and to separate the cellar from the above-located floors and also for registration of attic-floor room. In certain cases concrete products serve as material for wall construction.
It is interesting! Use of plates not only accelerates construction process, but also helps to provide stability to the building. Panels of overlapping are expected any loadings. They are considered as the checked and reliable elements enhancing rigidity of design.
Irrespective of the size, plates are made of concrete mix that provides to products ability to maintain heavy loads. In addition, products are characterized by high fire-prevention properties, are practically not subject to influence of moisture and temperature drops. Generally plates are classified by features of production because monolithic and hollow panels differ not only on exterior and the price, but also on technical characteristics. Generally the sizes and type of the used concrete influence the prices of reinforced concrete slabs of overlapping.
In prices not only cost for one plate, but also key parameters is specified to thicket and also it is specified how many plates it is possible to deliver by machine for time. The price dispersion is quite high because the indicator is influenced by many factors.
Features of production of concrete slabs of 2 m ³ and designs of other sizes
Steel concrete represents the material consisting of concrete mix, strengthened by means of reinforcing rods or wire. Such combination of components does the different size reinforced concrete slabs by strong construction material. Thanks to the fact that steel reinforcing rods are in concrete mix they are reliably protected from corrosion and harmful effects of the environment.
In turn, steel elements improve the bearing characteristics of concrete mix which differs in relative fragility. As a result of such combination reinforced concrete constructions are characterized by ability to resist to compression.
Thus, irrespective of the size, plates consist of such elements:
- concrete which is easy, heavy or silicate.
Reinforcing inserts represent steel rods or wire bunches which, in turn, are divided into such types:
- Workers. Take place in the lower part of concrete products and work for bend.
- Mounting. Make basis or skeleton of design, their main task – giving to plate of volume and fixing of placement of rods of principal reinforcement.
The heavy, intense concrete consisting of water, cement mix and special filler which is divided into such types as is applied to production of overlappings:
- coarse-grained, consisting of crushed stone or limestone;
- fine-grained, which basis – quartz sand.
The main active components of which concrete consists are cement and water. Thanks to their interaction the cement stone fastening filler grains therefore the integral monolith turns out turns out.
Interesting information! Because cement does not interact with filler, it is considered inert material. However filler, irrespective of granularity, has the main impact on properties and structure of concrete.
If at production of plates previously compressed concrete which is called intense is used, rods in a little stretched state are applied to its reinforcing that considerably increases durability of overlappings. The volume of products will be influenced not only by the size of concrete slabs, but also characteristics of the parts used in production.
Types of floor slabs, sizes: main norms
The increasing popularity is gained by monolithic and frame buildings which essence consists in forming of one continuous plate on all surface of the floor. The main shortcomings of monolithic construction – high cost, need of creation of preliminary framework and unceasing process of underpouring. For this reason finished concrete products do not lose relevance and are actively used, especially in private building.
In addition, lower prices of concrete slabs of overlapping and the sizes of products which large number in outlets is provided allow to choose suitable option for each specific building depending on the selected budget and architectural idea. Plates are easily mounted and promote acceleration of process of construction of buildings, and their laying does not require carrying out additional installation works. Other significant advantage the lack of shrinkage at reinforced concrete slabs of overlapping is considered.
Such designs are characterized by the raised rigidity indicators, they are steady against moisture and temperature drops, have high heat-insulating and sound-proof properties. At construction of residential units also gas-tight structures are used. In most cases the allowable load on floor slabs makes 800 kg/m ², and the maximum pressure which products are expected begins from 8 kPa. As the houses built with use of floor slabs are under construction long ago, it is possible to note also the long term of operation. In the offered list main types and the sizes of plates of overlappings are considered:
- Multihollow. Have width from 1 to 3.6 m, length from 1.7 to 9 m. Thickness, depending on model, changes from 16 to 30 cm. Differ in presence of hollow through holes.
- Ridge national teams. On norms the sizes ribbed floor slabs are provided by such parameters as height – up to 40 cm, width – up to 3 m, length varies from 6 to 18 m.
- Solid-web complementary structures. Length – from 1.8 to 5 m, height – 12-16 cm.
Interesting information! All characteristics and the concrete goods sizes (floor slabs) are regulated by norms. Depending on product type in addition can be equipped with releases of armature and also local cuts and openings.
When choosing concrete goods of designs for construction, in addition to key parameters, it is important to consider also the weight of products which will influence type of the used load-lifting equipment. Often on construction sites there are cranes expected raising of designs up to 5 tons. For example, the concrete slab of 2 m ³ can weigh from three more to 4.5 tons what can be too much for the normal crane.
Hollow floor slabs: sizes, main types
It is the most widespread type of concrete products most of which often is issued the industrial enterprises. Thanks to features and variety of the sizes concrete slabs of multihollow type are widely applied to industrial, multi-storey and private building. Presence of cavities helps to cope with laying of communications and heating mains.
Almost completely the plain and smooth surface of round hollow panels allows not only to mount quickly interfloor overlappings, but also simplifies work on performance of floor tie and registration of ceiling. Availability of emptiness at the same time does not affect ability of plates to maintain heavy loads. Depending on internal section and also from form and diameter, allocate cavities of the following types:
Besides that availability of emptiness considerably reduces the mass of floor slabs, hollow panels differ also in other advantages which treat:
- Economy of concrete mix by production that reduces cost value of finished products.
- Good operating ability. Multihollow plates of overlappings have high rate of noise isolation and heat insulation which increase quality of ready construction.
- Facilitate process of laying of communications. Emptiness in plates are used for making not only cables, but also other communication highways, for example, of pipes of different diameter.
- Wide choice of the sizes and prices of floor slabs. On production it is possible to find panels practically of any size, including also non-standard dimensions, but they will be a little more expensive.
- Simplification of all design. Thanks to the fact that multihollow plates have smaller weight on the base small impact will be made that will positively affect stability of all design.
Features of production and advantage of use of these or those types of products
Depending on features of production hollow plates are divided into hollow shuttering, the hollow facilitated and hollow formless.
Production of production of shuttering hollow plates looks thus:
- Concrete solution is filled in in the prepared timbering from metal with the reinforcing elements and the metal gauze located inside.
- Then as a result of vibration concrete well is stamped and exposed to processing in hydrothermal boxing in which temperature is 80 °C, and the absolute humidity reaches value of 100%. For 7-12 hours temperature in boxing steadily goes down.
- After mix completely stiffens, the ready reinforced concrete slab is taken for the fixed steel eyes by means of which mounting of panels is facilitated. In warehouse all plates undergo marking and receive technical documentation.
As for the facilitated floors, they are considered as the upgraded version of plates hollow shuttering which differ in the reduced thickness. If standard dimension of reinforced concrete slabs of overlapping makes 22 cm, then thickness of the facilitated version – only 16 cm that, in turn, influences the final weight and volume of product. So, the volume of concrete slab of 2.4х1 m of the facilitated type will be equal to 0.38 m ³, and the volume of standard plate hollow shuttering the same size reaches already 0.52 m ³, at the same time the weight of the first plate will be 550 kg, and the second – already 750 kg that indicates essential difference in weight.
Thanks to the fact that by production of plate more dense reinforcing using reinforced armature is used it maintains the same weight, as well as hollow plates. Respectively, use of plates hollow facilitated is considered more economic because at the price they are a little cheaper, and the foundation load will be smaller. Thanks to the fact that such plates occupy less than the volume for one delivery by machine it is possible to bring more plates that cuts down expenses on delivery of products.
Plates which are made without application of timbering are made as a result of process of continuous casting of concrete mix, and the final form of the panel is given by the forming machine. Such principle of production allows to release plates of big length – to 9 meters which at the request of the customer can be cut on any pieces with an accuracy of several centimeters. It gives the chance to use the different size of plate of floors for registration of difficult architectural elements.
Generally thickness of plates is 22 cm though in certain cases it is possible to meet also others on product height. The main advantage of plates hollow formless – opportunity to apply to product wall construction in vertical position.
It is interesting! The majority of industrial productions make shuttering plates because for their release it is not required to get additional equipment.
Basic sizes of floor slabs of multihollow type
Standard dimensions of floor slabs of hollow type change in such limits:
- length varies from 1.5 to 9 m;
- width – from 1 to 1.8 m;
- the minimum weight of plate is 500 kg;
- the maximum weight exceeds 4 tons.
It is also necessary to consider that durability of panels is influenced also by diameter of internal emptiness: than the size of through hole is less, especially the product is considered strong. For example, different types of plates are characterized by similar dimensions, only in the first case diameter of through holes is equal to 159 mm, and in the second – 140 mm it means that plates differ in bigger bearing capacity.
The weight which overlapping is capable to sustain is considered indicator of design load, including also value of curb weight. The maximum load on floor slab depends generally on type of concrete and on thickness of plate most of which often equals 22 cm. On productions options of the increased stability 30 cm thick meet – it is plates with marking 6 and also the facilitated designs which height – 16 cm.
Multihollow plates of overlappings are widely used at construction. Irrespective of the chosen type, as a result all the same at any number of floors the high-strength design will turn out. In spite of the fact that plates differ in method of production, they after all are intended for the solution of similar tasks.
What it is possible to learn about characteristics and the sizes of floor slabs
Not each builder needs to study features of production of different types of panels before purchase, but everyone who should face purchase of materials for building has to know how to decipher the marking specified on products. Marking of each product is made according to norms.
On product 3 alphanumeric groups separated by dash and points usually are specified. In the beginning the type of the panel and basic sizes of slab roof, such as length and width are usually designated. It is important to know that all values are specified in decimeters and are rounded to the whole value. In addition, in designations bearing capacity of overlappings is noted or it can be the indicator of design load measured in kilopascale or kilograms on square meter of product.
If the plate made of intense concrete in addition is got the class of the reinforcing steel is specified. The type of concrete usually on products is not designated.
The third group of marking often contains such characteristics:
- gases resistance;
- ability to maintain seismic influence;
- presence of additional mortgage elements.
Differences of floor slabs: sizes, prices and other parameters
If to speak about thickness parameters, all types of multihollow plates have values from 160 mm to 300 mm, but the standard is considered to be 220 mm. As for length, plate hollow formless differ in the increased dimensions – the peak value reaches 12 m here, at the same time it is possible to execute cutting of product with an accuracy of 10 cm. Standard length of plates hollow shuttering – up to 7.2 m, at the same time the step is accurately regulated, and the maximum length of the panel hollow facilitated reaches 6.3 m.
Width of panels of any type generally standard is also characterized by such values (in meters):
Plates hollow formless most often are issued 1.2 m wide, it is possible to meet m options 1 and 1.5 much less often. Products of formless plates 1.8 m wide practically do not meet. Standard load of multihollow plates makes 800 kg/m ². However the maximum load on plates hollow shuttering reaches 1250 kg/m ² while it is possible to order plates the hollow formless, expected loading 1600 kg/m ².
Helpful advice! If to get plate with open cavities at end faces, they should be closed up surely, using cement slurry and heater.
Important difference of plates hollow shuttering and hollow formless is the smoothness of surface: while the first option cannot brag of plain surface, plates hollow formless, thanks to smoothing of extruder, have smooth and attractive appearance. The average density of concrete slabs, irrespective of look, is 1400-2500 kg/m ³.
What is represented by ridge plates, their main characteristics
Ridge floor slabs still are called P-shaped. They have received the name thanks to in parallel to the located two stiffening fins between which distance generally makes 600 mm. The additional rigidity of products is provided owing to reinforcing which allows to cut consumption of concrete and at the same time to keep durability affecting resistance of design to bend. Utilization properties of products increase thanks to availability of several cross located edges. Plates from concrete of B15 or B20 brand are made.
Taking into account external features of the panel are divided into 2 types:
- Plates which differ in lack of aperture in regiment.
- Blocks in which there is the cut aperture. The main advantage of use of ridge plates of this brand – possibility of carrying out air duct or creation of the air shaft.
Because of special exterior and specific characteristics P-shaped floor slabs are more often applied at construction of uninhabited designs, such as garages or warehouses. At construction of residential units it is inexpedient to use such plates for creation of interfloor space because they have no such plain surface as other options of overlapping. The uneven ceiling will look ugly, to esthetically sheathe it will be difficult and also there will be difficulties with laying of communications.
It is interesting! In certain cases ridge plates are applied to creation of thermal or water systems.
The main distinctive feature of ridge panels in comparison with other types of overlapping – height. Thickness of concrete slab of P-shaped form usually is in limits of 30-40 cm. Thinner options are used for construction of small buildings and for separation of the attic from the room. Plates 40 cm thick can often be met on construction sites of objects of industrial function.
The sizes of ridge floor slabs differ from each other as well on width: the value of this parameter is in limits of 1.5-3 m, and each look has the advantages. So, construction with use of three-meter panels will quicker take place in view of bigger width that will allow to reduce not only temporary, but also labor expenses. If to apply narrower one-and-a-half-meter plates, construction will come out stronger.
Other characteristics of ridge floor slabs: sizes and other parameters
In comparison with the sizes of plates hollow shuttering, overlappings from ridge panels considerably exceed them longwise. Generally on productions products which length is 6 or 12 m meet. Also versions of panels of 18-meter length are available to individual production. As well as in other cases, their weight also depends on the size of plates that it is especially important to consider when transporting products and during creation of the plan of mounting.
The floor slab for the house of 12 m in size can weigh from 4 to 7 tons though weight of 1.5-3 tons is considered average value. If desired it is possible to order plates from more lightweight-aggregate concrete that will affect product weight. All P-shaped designs for convenience are equipped with mounting loops.
Upon purchase it is necessary to pay attention to presence of the openings intended for laying of communications and also to quality class, used in production. All these characteristics as a result also affect bearing capacity of construction. The maximum load on floor slabs of ridge type makes 180-830 kg/m ².
As for the price, ridge plates, in comparison with plates hollow shuttering, a little cheaper and also on weight they easier multihollow overlappings. The main reason for which they are got less often than other options, – high conductivity of cold.
Floor slab thickness on the upper shelf does not exceed 5 cm. It means that even at small subzero temperature the thin shelf for a short time will pass cold in the building. For this reason ridge overlappings need additional warming that involves excess time and financial expenditure.
What influences the floor slab size: standard dimensions of monolithic products
Monolithic plates take special position in classification of overlappings in view of the fact that their installation is made only in special cases.
Thickness of monolithic floor slab generally depends on product length:
- if length is 6.6 m, thickness will be within 16 cm;
- with length of 3.6-4.2 m thickness does not exceed 12 cm.
The price and the concrete goods size of floor slab of monolithic type directly depend on product thickness. Than the product is thicker, especially it differs in considerable weight, but it is necessary to consider that at this indicator equal to 16 cm, products will have the increased characteristics of sound insulation and heat insulation, and thin plates should be warmed and soundproof in addition. In spite of the fact that the monolith size is also regulated by norms, it is possible to make under the order products by the individual sizes. When choosing dimensions it is necessary to consider that the more and heavier the product, the will be more difficult to bring him and to lift on the necessary height.
Production of monolithic plates assumes use of the armature making basis of future design. The armoring lattice keeps within so that the distance between it and the body of timbering did not exceed 3 cm. The timbering represents folding design which is applied to giving of form to plate and reminds itself box. Thickness of steel rods has to be from 1 to 1.2 cm. For production of plates of this type quality concrete of M200 brand is used.
Helpful advice! On trading floors it is possible to meet reusable timberings which allow to be engaged in production of plates independently. The main minus of monolithic construction – the long time of hardening which is up to 28 days. Therefore it is better to carry out construction to warm season because the increased humidity and frost stretch hardening terms.
It is also important to take into account that the monolithic concrete slab of 2 m ³, submerged on the basis, will be slightly heavier than multihollow or ridge plates that needs to be considered when calculating bearing capacity of supporting structure of the building. Also raising of plate will require the crane with big loading capacity. For this reason monolithic plates, big by the size, unlike panels hollow shuttering, are made directly on construction site.
What allocate kinds of monolithic floor slabs: sizes and prices of products
Monolithic overlappings are divided into 3 types, each of which has the differences, way of laying and final cost apiece.
Allocate such versions:
The frame type of overlapping, depending on what surface the plate – smooth or ribbed has, differs also in the nature of use of designs. The plate with ridge surface is stacked perpendicular to edges, and smooth products are mounted perpendicular to plates. The rigidity of the ready building also depends on the correct laying.
In construction 2 types of beams are applied:
- main which have the large diameter of section;
- minor – with smaller diameter.
For flights of the considerable size overlappings with three-meter flight are used. On wall monolithic beams from steel concrete which then connect to the main plate of concrete goods keep within and are in addition reinforced. Usually beams keep within at distance of 1.3-5 m from each other. For achievement of bigger rigidity they are in addition fixed in steel concrete belt by means of anchors. The frame type of overlapping is used where surely it is required to receive equal ceiling that is especially relevant for inhabited construction.
During creation of flat slab floor columns with the capitals executed in the form of the inverted pyramid are applied. Section of reinforcing probes is 8-12 mm. Capitals differ in release of fittings from two parties which, in turn, enter plate and add rigidity design. Thickness of flight of frameless plates is 1/35-1/30 concerning length of the product.
Recently even more often columns and plates are concreted at the same time. The price directly depends on the amount of overlapping.
Unlike ridge plates the lacunar type of overlapping is characterized by the fact that here edges are located in both directions. The main advantages of use of this kind of overlappings – the reduced design weight, big flexural strength which is provided by grids of edges.
During construction on site of joint of column and overlapping reinforcing strengthening at which probes of column are implemented into timbering cavity is applied to giving of design of bigger reliability. Diameter of section of probes is not less than 8 mm.
Main advantages and shortcomings of use of monolithic plates
Monolithic plates of overlappings, in view of the features, are often used at construction of buildings with the difficult architectural project and if the building differs in non-standard parameters and is characterized by difficult corners and forms. The main advantage of monolith – the enhanced rigidity of the building therefore it is applied when it is required to execute the construction expected heavy load.
For example, relevant to use monolithic plates at construction of industrial workshop in which there will be not only static, but also dynamic load caused by constant vibration of the equipment.
Other advantages of monolithic products:
- Economy on delivery. Because of the big size of plate gather directly on the building site that allows to save on logistics and also loading and discharging. Besides, there is no need to equip warehouse for storage.
- Availability of the construction materials used for production. Concrete can always be bought or made on building at once, and waste of secondary ferrous metal also will be suitable for fittings.
- Simplification of work on interior finish. Thanks to application of timbering the lower face of plate will differ in plain and smooth surface that will allow to carry out quickly finishing work with the minimum expenses.
- The increased heat-insulating characteristics. The lack of joints between plates increases ability not only to keep heat, but also to absorb sounds.
- Long term of operation. In view of the fact that concrete protects steel rods which, in turn, raise functional performance of concrete from corrosion, the building will long keep durability. However it is necessary to consider that, these characteristics have also other types of overlappings.
- Wide choice of the sizes and forms. As monolithic plates by means of timbering can give any form, their use allows to issue portable balconies of rounded shapes and also to do smoother bends on building facade.
As for shortcomings, the main thing from them carrying out technically complex works because the monolithic plate of the necessary sizes with strength characteristics is made only by experienced specialists having the corresponding skills is considered. Dimensional parameters of products are calculated individually in each case, respectively, it is necessary to allocate additional costs of payment for work of the specialist in filling.
Other shortcomings of monolithic plates:
- Considerable weight. The lack of emptiness and the big sizes of products cause to finished product big weight that will demand creation of stronger base.
- Long term of hardening. On norms the period of hardening of concrete in timbering is 28 days that stretches construction terms.
Not to be mistaken upon purchase of plate for construction, first of all, in addition to the size, it is necessary to take an interest at the seller about goods origin and about reputation of the producer. It is important to check quality class and quality of the ready panel. It is not necessary to get products with explicit violations of integrity which will reduce bearing capacity of design. It is necessary to be convinced available passports of products, and then, proceeding from the necessary sizes, to select quantity of plates. The main thing – to understand that stability of the ready building also depends on quality of overlappings.