RU2595020C2 - Road slab - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention relates to construction, particularly, to structures of slabs of surfaces of the roads, car parks and various heavy-duty platforms. Slab contains concrete and metal rebar in lower part. Top edges of slab are made of fibre concrete, fibre of which when stripped does not harm bus of the vehicle and is made, for example, from glass fibre basalt or polypropylene.

EFFECT: improvement of reliability, durability and capacity of the road surface.

1 cl, 4 dwg

Description

The invention relates to the field of construction, in particular to the construction of slabs of coatings for roads, parking lots and various heavy platforms.

A known construction of a reinforced concrete product, in particular a reinforced concrete slab of fiber concrete, which is a concrete with dispersed reinforcement. The fittings can be metal (length 60-70 mm and diameter 0.25-1 mm), fiberglass, basalt polypropylene and other materials. Fiber-concrete products (in particular, slabs) have increased tensile, compression, fracture, cracking and shock resistance (Tsukovich S.M. et al. Technology of concrete aggregates. - M.: Vysshaya Shkola, 1991, p. 244 ; Nanazashvili I.X. Building materials, products and structures. - M.: Higher School, 1990, p. 57-64).

However, this design of slabs has the following disadvantages: the complexity of manufacturing fiber-reinforced concrete, the high cost, the difficulty of controlling the location of dispersed materials in the product, the manufacture of fiber is much more expensive than periodic reinforcement, when the concrete hardens, the fiber can change its location, the middle part of the slab (in height, middle layer) does not bending loads and fiber in this place is least needed (fiber overrun). The use of metal fibers for road plates is unacceptable due to wear of concrete and exposure of metal fibers and puncture of a vehicle tire. The disadvantage can be considered the difficulty with the disposal of products from fiber concrete.

The closest in essence to the invention is a slab of a road covering consisting of concrete and metal reinforcement located in the lower part of the slab (Babkov V.F., Andreev O.V. Design of roads, part 1, p. 297-300).

However, in the well-known solution adopted as a prototype, the joints of precast plates do not provide the transfer of forces and moments from plate to plate. Through the seams there is a squeezing of liquefied sand and underlying soil. A pothole forms under the ends of the plates and the end of the plate acts as a console. If in the middle of the plate metal reinforcement fulfills its purpose, i.e. the top of the slab works for compression, and the bottom for tensile, then the end of the slab, especially when a pothole is formed there, works - the top for breaking, and the bottom for compression. Moreover, cracks and then chips are formed in the upper part of the plate (at its end), which further increase the dynamic loads on the plate and put it out of order. To reinforce the extreme upper part of the plate, it is possible to lay metal reinforcement there, but since the protective layer is very small (2-3 cm - the smaller the protective layer, the more effective the reinforcement works), it is possible to expose the reinforcement, which can lead to a puncture of the tire and a vehicle accident . The connection of plates into a continuous road surface only by means of releases of working reinforcement on the end faces does not provide sufficient strength for connecting the plates to each other, which leads to a relative displacement of the plates vertically, deflection of the coating under the influence of a significant moving load, the complexity of the corrosion protection of the welded reinforcement and, as consequence, the destruction of the road surface.

The technical result of the invention is to increase the reliability, durability and carrying capacity of the road surface.

The specified technical result is achieved in that the upper edges of the slab are made of fiber-reinforced concrete.

The invention is illustrated by drawings.

FIG. 1: 1 - concrete, 2 - reinforcement, 3 - vehicle wheel, 4 - pothole, arrows indicate the direction of operation of the plate when the vehicle wheel is in the middle of the plate (above compression, below the gap).

FIG. 2 is the same as in FIG. 1, but the wheel of the vehicle 3 is on the edge of the plate. The arrows indicate the direction of operation of the plate (above the gap, below the compression). In contrast to FIG. 1 plate operation from the load of the vehicle wheel is opposite to the plate operation when the wheel is in the middle of the plate. The plate is not designed for such work (the top end of the plate is tearing).

FIG. 3 is the same as in FIG. 2, but the edge of the plate on which the wheel of the vehicle is reinforced with fiber-reinforced concrete 5.

FIG. 4 - concrete poured to the level of the AB line, 2 - reinforcement, 6 and 7 - removable partitions across the slab (form), 8 - form for pouring concrete for the manufacture of a road slab.

The invention works and is made as follows. As can be seen from FIG. 1, when the vehicle wheel 3 is in the middle of the slab, the top of the slab works to compress, and the bottom to break, and since concrete does not work well to break, the bottom of the slab is reinforced with metal reinforcement 2. When the wheel of the vehicle approaches the edge of the slab (Fig. . 2), then, on the contrary, the top of the plate works for breaking, and the bottom for compression. Since concrete does not work well in rupture, cracks form on the edge of the slab and then chips of concrete. To eliminate this drawback, the edge of the slab (upper part) is made of fiber-reinforced concrete 5, which works well for breaking and is very resistant to the formation of cracks and chips of FIG. 3. The fiber in the fiber-reinforced concrete must be made of fiberglass, basalt or polypropylene, one that cannot harm the tire of the vehicle. When it is exposed, metal fiber can cling to a tire, make a puncture, and make noise when a wheel hits. Fiber made of fiberglass, basalt or polypropylene, if they have a fine structure, work well in tearing and do not harm the tire of the vehicle when exposed.

A method of manufacturing such a plate is illustrated in FIG. 4. The manufacturing sequence is as follows: after installing metal reinforcement 2 in mold 8, concrete is poured to line AB (to a height after which fiber concrete is poured at the ends of mold 8), mold 8 is separated by partitions 6 and 7 (across form 8) and into the formed containers (3 pcs.) at the same time concrete is poured (the middle part between the walls 6 and 7) and the ends of the slabs are fiber-reinforced concrete. Simultaneity is necessary so that there is no bulging of concrete or fiber-reinforced concrete, and their rise to the top of form 8 occurs simultaneously.

To simplify the method of manufacturing a road slab, it is possible to apply fiber-reinforced concrete to the ends of the slabs by air spray.

The advantage of the proposed road slab over its analogues is that the upper part of the end of the slab does not form cracks and chips, the overhaul time for road repair is extended and due to this, the cost of operation and repair of the road is reduced, the speed of vehicles and safety are increased, since no chips are formed at the ends of the slabs, as well as less potholes are formed under the ends of the slabs, since the slab is more rigid due to the fact that fiber concrete works well against tension, cracks and chips.

Claims (1)

A concrete slab for roads containing concrete and metal reinforcement in its lower part, characterized in that the upper edges of the slab are made of fiber-reinforced concrete, the fiber of which does not harm the vehicle tire when exposed and is made, for example, of fiberglass, basalt or polypropylene.

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