FI109982B - Method and apparatus for making a concrete product and Concrete product - Google Patents

Description

109982

The invention relates to a method for producing a concrete product by extrusion technology according to the preamble of claim 1. The invention also relates to an extruder molding machine for carrying out the process according to the invention.

Concrete castings, such as cavity elements, columns or solid slabs, can be manufactured by extrusion technology. Hollow slabs and similar load-bearing structures with tensile stresses are reinforced with longitudinal reinforcements or steel braids.

15 The use of a transverse reinforcement as well as any additional reinforcement as a conventional rod or wire reinforcement is so difficult to arrange for manufacturing purposes that it is technically and economically impossible to use such an reinforcement. This limits the use of slabs in accordance with standard norms and also in terms of static and dynamic loadability and fire performance. Limitations are accentuated by wide tiles, large. at the edges of the openings and when the tile is under large point and line loads. These restrictions partly apply * ,. 25 also for products made by other continuous casting processes.

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In special cases, the element may also be cast from pulp mixed with fiber reinforcement, such as steel fibers, so that the element, e.g., hollow core slab, can be used in accordance with standard practice, taking into account the element's performance in static and dynamic loading. and in case of fire. However, the use of reinforced elements, such as tiles, is limited because the reinforcing material 35 significantly increases the cost of the casting compound, so the use of 109982 2 reinforced product is only justified in particularly demanding applications where the properties of the more expensive product can be sufficiently utilized. Steel fibers can be easily blended with the pulp used and are the most economical and cost effective. However, with current continuous casting techniques, it is only possible to produce products using one or at most two different grades of pulp. For example, sliding machines can first feed a mass portion of the product's lower surface onto a casting substrate, and then feed the remainder of the mass onto the lower layer. In this way, different grades of pulp can be used in the height direction of the product, but the layer thickness of the base mass must be small, at least for the manufacture of hollow core slabs, and the layer thickness cannot be varied. In the Extruder-15 jigsaws, the feeding of two different types of pulp has not been used, since the pressure exerted by the feed screws substantially affects the condensation of the casting. If part of the mass is fed directly to the casting tray underneath the feed screws, there is a risk that the lower part of the casting will be less compacted.

US 4450i28 discloses a method of placing a reinforcing mat on the surfaces of a * * * concrete-free concrete shell and casting fiber-reinforced concrete layers forming the outer surfaces of the slab. The thickness of the fiber concrete layer is *. * '25 the same throughout the length and thickness of the slab and the · · method does not provide additional reinforcement to the edges or end of the slab. Thus, the method is only suitable for producing one type of product and the slab always becomes homogeneous in each cross-section.

: 30 ···. The process of US 391 4359 produces a composite structure using both reinforcing fibers and filler beads. In this method, the manufacturing device is directly designed for a given amount of fiber, filler binder feeds, and the ratios between feed rates cannot be changed. In this solution too, the amount of reinforcement is always the same in every cross-section of the product, and it is not possible to produce an inhomogeneous product, e.g.

It is an object of the present invention to provide a method and apparatus for producing fiber reinforced concrete products by extrusion molding technology and a concrete product wherein the fiber reinforcement is divided into specific parts of the product so that different strength properties are obtained in different parts of the product.

The invention is based on dividing the fiber reinforcement from an inhomogeneous product volume so that at least one volume fraction of the product has more reinforcement 15 than the corresponding volume at least one other portion of the product, the method changing the proportion of fiber reinforced material as a function of time or molding.

. According to one aspect of the invention, at least two pulp containers are used in the manufacture of the concrete product. One of the tanks has a standard concrete mass and the other one has a fiber reinforced concrete mass. By controlling the ratio of these masses * *, it is possible to control the fiber content of the pulp in various * · '' parts of the element. The fibrous mass can then be moved through the feed * * · • t * '·' * screws at various points in the casting so as to obtain the desired fiber content.

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More specifically, the process of the invention is characterized by what is set forth in claim 1.

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characterizing part.

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The device according to the invention, in turn, is characterized by what is stated in the characterizing part of claim 10.

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The product according to the invention is characterized in what is stated in the characterizing part of claim 16.

The invention provides considerable advantages.

By the method of the invention, the fiber reinforcement is dispensed in desired amounts into desired portions of the element, thereby providing a reinforcement at more convenient locations. For example, fiber-10 reinforcement can increase the versatility, competitiveness and technical functionality of tensioned hollow core slabs. A smaller amount of fiber reinforcement provides an element as durable as before when the reinforcement is only placed at points that are subjected to a greater or different type of load than the other 15 elements. The elements to be manufactured can be lightened, thus diversifying their field of application. The static and dynamic durability of the hollow-core slabs produced by the process of the invention is improved, e.g. their load-bearing capacity and vibration and movement resistance as well as earthquake resistance are improved. They may be subjected to higher transverse loads. When added to the ends of the tiles, the fiber reinforcement reduces their distortion and improves shear resistance. Adding fiber reinforcement to the edges of the slab improves its lifting and torsional strength * • · · V · 25. The edge reinforcements in the openings improve the load-bearing strength of the tiles, · · «V, when added between the brackets between the slab cavities, the fiber reinforcement improves the • i shear resistance of the slabs and when added to the base of the slab. For large cavity top plate: 30 added with reinforcement to help the piece stay in shape during casting. The train piles made by the method according to the invention can be reinforced with fiber ends to withstand impact. If necessary, slabs or other products can be manufactured even in individual pieces, differently reinforced according to the load on the application. Various sizing options and structural solutions can be used more flexibly with the invention, since the entire slab does not have to be designed according to the maximum load located in a given area.

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The invention will now be further explored by way of exemplifying embodiments of the accompanying drawings.

Figure 1 is a side elevational view of one device 10 according to the invention for producing three concrete piles.

Figure 2 is a front view of the device of Figure 1.

Fig. 3 is a cross-sectional view of one of the cavity plates 15 according to the invention.

Figure 4 is a cross-sectional and perspective view of another hollow plate according to the invention.

Figure 5 is a cross-sectional view of a third hollow plate of the invention.

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Figure 1 shows a device for manufacturing three concrete piles. The apparatus comprises a metal body 7 fitted with a V * 25 conical container 8, the upper and lower parts of which are open. The partition 12 divides the container 8 into two parts, the basic container 1 and the reinforcement container 2 so that the upper and lower parts of the container 8 are also divided into two parts. The volume ratio of the reinforcing container 2 to the basic container 2 may be selected by mass. For example, a ratio of 1/3 is needed to feed 30 yuan. A feeding device 4 is mounted inside the strong summer container 2. The feeding device 4 consists of a wide gear wheel 9, a shaft 10 which rotates the gear wheel through the container and an engine 35 which is rotatable outside the container. At the bottom of the partition 12 is a hinged 109982 6 adjusting hatch 3, which defines the ratio of the lower openings of the container parts. The size of the adjusting hatch 3 is dimensioned such that the hatch 3 is capable of covering, where necessary, the opening in the lower corner of each container half 1, 2 so that the angle between the adjusting hatch 3 and the perpendicular to the ground does not exceed a certain angle (e.g. whereby the hinge hinge is not subjected to excessive stress under the weight of the concrete mass. Below the adjusting door 3, a tube 19 is arranged in the lower part of the container, the lower part of the tube 19 being aligned with the opening in the body 7. Inside the frame, below the pipe, there are three feed screws 5 horizontally. The frame 7 is sealed at both sides of the feed screws. The feed screw 5 is mounted between the body 7 and the hollow mandrel 6. Approximately at the height of the lower edges of the feed screws 5 on the wall 15 on which the feed screws are mounted, the body 7 has openings for feeding rod reinforcements. Below the feed screws 5 are concrete feed chutes 24 which guide the mass towards the nozzle area.

. In the manufacture of articles, the extruder section of the apparatus functions "V like a conventional extruder, i.e., feed screws 5 squeeze the concrete mass through the nozzle formed by the upper wall 20 and laterally dividing side and partition walls 21 and cavity mandrels 6. '· *' 25 is formed and formed by the pressure of the feed screws 5 • ♦ · '· *' in the nozzle portion 20, 21, 6 and the movement of the sealing device 22 attached to the top wall 20. The feed screws 5 are adapted to • * · • · 20, 21. The nozzle member is shaped such that, when pressed through, the concrete mass is formed into three pieces of square edges with a hollow cylinder formed by an on-roll mandrel 6. The core 7 has

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fixed axles 13 and 14 to which are mounted two wheels, axle 13 wheels 15 and 16 and axle 35 wheels 17 and 18. The device advances on the casting wheel due to the force exerted by the feed screws 109982 7.

The device according to Figure 1 can be used to manufacture train shoes by the following method. Prepare concrete mass and 5 steel fibers. Mix the steel fibers with a part of the concrete mass. An unreinforced gray mass of concrete is fed into the base tank 1 and the fiber reinforced mass into the reinforcement tank 2. If necessary, rotation of the feeder 4 ensures the passage of rigid fiber reinforced concrete from the reinforcement tank 2 10. The position of the adjustment hatch 3 is controlled by adjusting the ratio of the lower openings of the main container 1 and the reinforcement container 2.

The ratio of the lower openings determines the mixing ratio of the concrete masses passing through the control hatch and thus the fiber reinforcement content of the pulp going through the system over the length of the products to be cast or as a function of casting time. Thus, the feed rate of the materials can be bound as a function of time or position of the casting machine. From the control hatch 3, the concrete mass is drained through a cylindrical tube 19 through a horizontal cross-section to the ti-20 blade surrounding the feed screws 5, from which the mass is pressed through the feed screws through the nozzle part • · · * · _ '. At the height of the feed screws 5, longitudinal rod reinforcements are fed through the openings in the frame 7 around the bearing position of the screws 5 · · · ··· *. The machine moves when the modified mass is completed and the mass can be left to harden on the substrate: 25 23.

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The apparatus described above is suitable for the manufacture of products in which the • fixed mass varies with the product

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longitudinally or vertically. Because the feed screws: 30 do not actually mix the mass but push it forward, the * * · ton of gray concrete mass to be fed to the rear of the feed screws is transported more below the feed screws * ·>, guided by the feed trough 24. The position of the hatch 3 controls how much of the feed mass is reinforced and where the feed screws 5 are placed. If the hinge 109982 8 is turned towards the opening of the container 2, the amount of pulp fed therefrom decreases, and at the same time its proportion in the height decreases, i.e. the proportion of fiber reinforced or unreinforced pulp in the cross sectional direction changes. If the one of the openings of the jom-5 is completely closed, then only one type of pulp will be cross-sectioned. By selecting the container into which the fiber reinforced pulp is to be fed, it is possible to select whether the reinforced pulp is to be poured into the lower or upper part of the product when operating as described above.

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Figures 3-5 illustrate three different principles for dividing a fiber reinforcement into a hollow mandrel. In Figure 3, the fiber-reinforced mass is fed to the lower portion 25 of the slab so that the proportion of alloyed pulp extends across the cross-section of the heels 26 of the on-15 rolls. In this way the load-bearing capacity of the slab can be increased, for example in deck structures and other structures where the slab is supported at its ends. The slab of Fig. 4, with reinforced mass placed in zones along the length of the slab, is suitable for sites where a 20 area is subjected to a spatially delimited load, such as a line load. Suitable applications are, for example, structures underneath a load-bearing wall or structures under conveyors or rails. In the slab of Fig. 5, a strong * · · $ '' groove is placed at the edges of the slab to provide good compression strength and shear strength in the edge V: 25 areas.

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V * In addition, transverse reinforcement is used in this slab. These are some examples of the * ·:, * ·· product of the invention and the amplifier input methods described herein may be combined. In addition, of course, different mouthpieces can be used. 30 rye of the reinforced material or reinforcement feed rate t · * such that the proportion of reinforced material changes, for example, in height or laterally along the length of the slab. One can, for example, make a tile having reinforcements at the ends in the cross-section of the entire tile and in the central portion only as a prelude to the lower portion or at the edges.

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Figure 6 shows a device in which the mass can be distributed more efficiently in different heights of the slab. Here, a movable partition wall 5 30 extending close to the upper surface of the feed screws 5 is disposed in the tube of the bulk container 8. This partition allows effective control of the part of the feed screw 24 and the flow of the fiber reinforced material in the height direction. If the bottom edge 30 of the septum is near the beginning of the feed screws, the mass is effectively directed by the feed trough to the bottom of the cast. On the other hand, if the partition 30 is closer to the hollow mandrel 6, the proportion of pulp from the container 1 in the cross-section increases. In this embodiment, each portion of the container further has separate closure members 31, 32 for independently controlling the amount of pulp feed to each of the 15 pulps.

In addition to the foregoing, the present invention has other embodiments.

The apparatus according to the invention may have fiber reinforcement feed nozzles at various locations along the nozzle region. height and height. The mass can be pressed through the nozzle by means of feed screws or by pumping. When using such equipment, the fibers are mixed with the binder 25, for example in a cementitious adhesive, and the amount of reinforcement supplied by the nozzle can be adjusted over time by manual or electronic transfer of products from the database. based on information. The feed screw rotation speed is also adjustable as a function of time. An apparatus according to the invention '** 30 and similar to that of Fig. 1 can be made in which the feed hatch 3 is divided into at least two separately hinged parts, whereby the fiber reinforcement: Y: content of the manufactured element can be adjusted; ··· Transverse direction. It is conceivable that the concrete mass 35 is fed to the casting machine by means of pipes separated from a casting machine such as a tank 109982 10 or from a pulping plant. However, in this case, a large amount of pulp remains in the pipeline, especially in production lines for long products.

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The shut-off devices in separate containers and in the pulp feeders may be of a type other than the hatches described above, for example sliding gates or bulging shutter beams made of flexible material. The pulp feed tube 19 connected to the reservoir 10 may be shaped as a replaceable nozzle tube having routes or channels for feeding pulp to a desired location in the longitudinal and transverse direction of the cast. Such a nozzle would have separate pipes passing from the container to the opening on top of the supply screws 15. With a replaceable nozzle, the device can be fitted more quickly to make a variety of products. Apparatuses of different shapes of hollow mandrels according to the invention can be manufactured and used in various forms to produce lightweight structures. In accordance with the invention, such products can also be manufactured. which use several different concrete masses. . ·. than just fiber-reinforced pulp and regular product-

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unreinforced concrete mass. Materials other than steel fibers such as synthetic fibers, glass fibers and other metal fibers may be used as reinforcing material. However, steel fibers are reasonably priced, • · · strong and have a coefficient of thermal expansion equal to that of concrete. . they have very high inexpensive reinforcement material. The fiber reinforcement can also be mixed with the concrete in the form of additives such as cement adhesive.

Claims (20)

1. A method for manufacturing a fiber reinforced concrete product, wherein method 5. concrete pulp is pressed through a defined cross face (20, 21, 23) with at least one feeder screw (5) - at least two different materials are prepared for use in the manufacture of the concrete product, of which at least one contains fiber reinforcement; the two materials are dosed to the feeder screws (5), and 15. the material's dosing amounts are regulated so that the ratio of the amount of material containing "fiber reinforcement" to the amount of unfinished material is such that the final product's: heterogeneously distributed in ....: 20 the volume of the product so that at least part of the volume of the product contains more gain than the corresponding volume in at least another part of the product, characterized in that 9. : The amount of fiber reinforced material is changed as a function of time or the position of the casting machine. 2. A method according to claim 1, characterized in that the amount of fiber-reinforced material is adjusted in such a way that at least at the end portions of the product only reinforced material is fed. 5 Method according to claim 1, characterized in that the amount of fiber-reinforced material is regulated in such a way that at least to the edge portions of the product only reinforced material is fed. 4. A method according to claim 1, characterized in that the amount of fiber-reinforced material is regulated in such a way that at least to the sub-surface of the product is fed only reinforced material. 5. A method according to any of claims 2 to 4, characterized in that at least one voltage rack is provided in the product during casting. Method according to any one of claims 2 to 4, characterized in that at least one mold mandrel (6) is formed in a defined cross-section to form a cavity in the product. • · · V: 20 Process according to Claim 1, characterized in that in V * a defined cross section is provided at least two mold mandrels (6) to form cavities in the product and fiber reinforced material is fed at least part of the volume between the cavities. »· ·« • * · • I »!!! 25 8. A method according to claim 1, characterized in that the fiber reinforcement is mixed in the additive material and measured together in the ingot. 109982 9. A method according to claim 1, characterized in that the fiber reinforcement is mixed in the concrete pulp and fed together with the ingot. Apparatus for manufacturing a fiber-reinforced concrete product, comprising: - means (20, 21, 23) for forming a defined cross section, - at least one feed screw (5) for feeding concrete mass through the defined cross section for forming the concrete product, means (1, 2, 19) for feeding concrete mass to the feeder screws (5), comprising means at least means (2, 19) for feeding at least concrete mass and means (1, 19) for feeding of at least one other material to be used in the ingot, and • means (3) for changing the feed ratio: ··: of concrete pulp and other material so that the • • ··· pouring between the amount of material containing . "• .20 fiber reinforcement, and the amount of unreinforced material is such that the final product fiber reinforcement is heterogeneously distributed in the product. Volume so that at least part of the product contains volume. more strength than the corresponding • 25 volumes in at least one other product portion, characterized by the amount of fiber-reinforced material. can be changed as a function of time or the position of the casting machine with the aid of the concrete pulp and the other pulp. 19 109982 Device according to claim 10, characterized in that the means for feeding the materials comprise two containers (1, 2) for different concrete masses and means (3) for changing the input ratio of the masses. 12. Apparatus according to claim 10, characterized in that the means for feeding the masses comprise a nozzle tube which is divided into at least two feed channels for feeding different concrete masses to the feed screws (5). Device according to claim 10, characterized in that the means for feeding the materials comprise at least one feeder nozzle for feeding an additive containing fiber reinforcement into the ingot. Device according to claim 10, characterized by means for feeding fiber-reinforced material into the edge portions of the product. Apparatus according to claim 10, characterized by means for inserting fibrous reinforced material into the lower surface (24,30) of the product. 16. Concrete product comprising at least one type of concrete mass 20 and at least one fiber reinforced mass and the ratio between the amount of material containing the fiber reinforcement and the amount of the non-reinforced material is such that: * ·, · the final product fiber reinforcement is heterogeneously distributed in. * · '. The volume of the product says that at least a portion of the product's • · · • .25 volume contains more reinforcement than the corresponding volume in at least another product part, characterized in that the amount of fiber-reinforced material varies in the product's · · · *, · * · Longitudinal direction. 20 1 0 9 9 8 2 17. Product according to claim 16, characterized in that at least the ends of the product exhibit material containing fiber reinforcement. 18. Product according to claim 16, characterized in that at least the lower surface of the product has a fiber-containing material. 19. Product according to claim 16, characterized in that at least the edge portions of the product exhibit material containing fiber reinforcement. Product according to claim 16, characterized in that the material containing fiber reinforcement is distributed in the longitudinal direction of the product in alternating sectors with non-reinforced material. • · • · · · MM · · 1 · · I I t * · · • f · • · · · · · · · · · · · · · · · · · · · · · · · · · · · I