Prefabricated concrete component

Abstract

The utility model relates to a precast concrete component, which comprises a body and a prestressed reinforcement in the body, and is characterized by further comprising a sleeve, a taper hole and an internal threaded hole are arranged in the sleeve, the internal threaded hole is positioned on the right side of the taper hole, and the aperture of the taper hole is gradually enlarged from left to right; the conical clamp is located in the conical hole, the peripheral face of the conical clamp is matched with the conical hole, an inner tooth hole is formed in the center of the clamp, clamping teeth are arranged on the peripheral wall of the inner tooth hole, and the prestressed reinforcement is locked by the inner tooth hole; an inner threaded hole is formed in the sleeve, the end of the prestressed reinforcement is contained in the inner threaded hole of the sleeve, an annular space is formed between the prestressed reinforcement and the inner wall of the inner threaded hole, the right end of the inner threaded hole is open, and the inner threaded hole can be used for being in threaded connection with other components or the annular space can be filled with sealing materials. The end plate has the advantages that mechanical pile splicing is facilitated, the end plate can be mounted subsequently, the mechanical properties such as bending resistance and shearing resistance are better, and the rib distribution density can be increased. The utility model further relates to a production method.

Description

Technical Field

[0001] The utility model belongs to the technical field of concrete foundation engineering of various building structure systems, and in particular relates to a prefabricated concrete component. Background Art

[0002] Due to the high tensile strength of prestressed steel (for example, the design tensile strength of steel strand is 1320 MPa, with a maximum tensile strength of 1960 MPa), Chinese companies and research institutions have conducted extensive research on the use of prestressed steel in precast concrete components in recent years. During the manufacturing process of these prestressed reinforced concrete components, conical clamps are typically used to secure the prestressed steel. The core technical considerations are how to conveniently and accurately connect and secure the prestressed steel to the conical clamps, and how to achieve maximum consistency in the tension applied to each prestressed steel bar.

[0003] For example, a Chinese invention patent with patent number ZL201410034851.8 (publication number CN103741672B) entitled "A pre-tensioned centrifugal concrete pile with steel strands and a manufacturing method" discloses a method of locking the steel strands: a conical hole is opened on the end plate, and a conical chuck assembly composed of multiple clips is placed in each conical hole. The steel strand passes through the inner tooth hole of the chuck assembly and is locked on the end plate. This locking method is simple, but during the installation process of the steel cage in the early stage of production (before the steel strand is tensioned), it is difficult to combine and fix the end of the steel strand with the tapered clamp assembly, and this combination will be very loose. It is often necessary to use a hammer to hammer the end of the steel strand and the clamp assembly into the tapered hole on the end plate to achieve a tight combination of the two and lock the steel strand on the end plate, which will cause direct misalignment of the clamp assembly and the steel strand. In addition, when the end of the steel strand is extended into the clamp assembly, it will also cause relative misalignment of the clamping pieces of the clamp assembly and irregular internal tooth holes, thereby reducing the internal tooth hole's fit for the steel strand. The clamping force of the steel strands is too low, and the position accuracy of the steel strands locked by the clamping assembly is not high, that is, the clamping and locking positions of the steel strands in the length direction of each clamping assembly are inconsistent and non-uniform, which makes the tension of each steel strand inconsistent, which seriously affects the mechanical properties of the pile body. In addition, after the pile body is formed, the prestress of the prestressed steel bar locking end plate is inconsistent, which also affects the mechanical properties of the pile body end. In addition, after the concrete pile is formed, the end of the steel strand is firmly locked in the conical clamping assembly under the action of prestress. Even if the tension of each steel strand is found to be inconsistent, it is difficult to make remedial corrections.

[0004] Another example is the Chinese invention patent "Pre-tensioned Centrifugal Concrete Pile with Steel Strand and Manufacturing Method," with patent number ZL201410036904.X (publication number CN103758120B), which discloses another similar steel strand locking mechanism: an anchor ring has a stepped through hole, the large hole portion of which is a threaded hole, and the small hole portion of which is a tapered hole. A conical chuck assembly composed of multiple clips is placed in the tapered hole. The steel strand is locked in the internal tooth hole of the chuck assembly. The anchor ring is connected to the end plate via a bolt connector, with the threaded section of the bolt extending into the threaded hole in the large hole portion of the anchor ring. This locking method is similar to the first method described above, but also suffers from the difficulty of the tapered chuck assembly to lock with the end of the steel strand, the low accuracy of the locking position, and the inconsistent clamping and locking positions of the steel strands by each chuck assembly along the length direction, which affects the mechanical properties of the pile body and the pile end. Furthermore, it is difficult to take remedial measures to address the inconsistent tensioning force of the steel strands.

[0005] The invention application with publication number CN104343118A discloses a tensioning device for manufacturing concrete piles with steel strands, which has a plurality of first through-holes on the anchor plate, a first connecting seat being detachably fixed in the first through-hole, a first threaded through-hole on the first connecting seat, a first push rod being threadedly connected in the first threaded through-hole, the inner end of the first push rod being against the outer end face of the clip assembly, the steel strand being pushed flush with the outer end face of the clip assembly by the push rod, and the concrete pile after centrifugation has no end plate with the end of the steel strand exposed; there is also an invention application with publication number CN110499754A, which also discloses a steel strand clamping component and a corresponding concrete pile, which has an external thread on the outer wall of the anchor ring for direct connection with the end plate, an internal threaded hole being provided in the anchor ring for fixing the installation plug, and a conical chuck assembly being placed in the conical hole of the anchor ring to lock the steel strand on the end plate. These two inventions respectively use a push rod and a plug to abut against the ends of the chuck assembly and the steel strand, so as to achieve a uniform length of each steel strand inserted into each chuck assembly, and thereby achieve a consistent tension force on each steel strand. However, although the accuracy of the conical clamps of the two inventions in clamping and locking the steel strands is improved, in actual operation, there is always mutual friction and jamming between the two during the process of inserting the steel strand ends into the tooth holes in the chuck assembly. Not every steel strand end and chuck assembly uniformly abut against the push rod or the plug as expected by the invention. It often happens that some chuck assemblies or steel strand ends are jammed, resulting in different lengths of steel strand inserted into the chuck assembly. The chuck assembly will also cause the clips to be misaligned and deformed, reducing the clamping force on the steel strand. Moreover, in actual production, it is difficult to ensure that the cut length of each steel strand is uniform. Each steel strand will have more or less length differences, which also makes it difficult for the invention to actually achieve a consistent tension force on each steel strand. Therefore, these two inventions will also have the defects of the above two patents that the conical chuck assembly is difficult to combine and lock with the end of the steel strand, or the position accuracy of the conical chuck assembly in locking the steel bar is not high, and the tension of each steel strand is inconsistent. Moreover, because the top rod and the plug block the end of the steel strand, it is difficult to detect and correct the problem of inconsistent tension of the steel strand.

[0006] Another problem with the aforementioned prior art method for locking prestressed steel bars is that the ends of the prestressed steel bars no longer extend after being locked by the tapered clamp. Therefore, this prior art cannot be used for long-line production (i.e., the simultaneous production of two or more concrete piles in a single long mold) of concrete piles with end plates, limiting its scope of application. Furthermore, the end plate holes corresponding to the concrete pile strands in the aforementioned invention cannot be connected to other external components.

[0007] In summary, the locking mechanism of the prestressed steel bars in the aforementioned prior art needs to be further improved. Utility Model Content

[0008] The technical problem to be solved by the present invention is to provide a prefabricated concrete component with a reasonable structure, convenient mechanical pile connection, subsequent installation of end plates, better mechanical properties such as bending and shear resistance, and increased reinforcement density in response to the deficiencies of the above-mentioned existing technologies.

[0009] The technical solution adopted by the utility model to solve the above technical problems is: a prefabricated concrete component, including a body and prestressed steel bars in the body, characterized in that: it also includes

[0010] A sleeve, wherein the sleeve has a tapered hole and an internal threaded hole arranged axially in sequence from left to right, the internal threaded hole is located on the right side of the tapered hole, and the aperture of the tapered hole gradually increases from left to right;

[0011] A conical clamp is located in the conical hole and its outer circumference is adapted to the conical hole. The center of the clamp has an inner tooth hole, and the peripheral wall of the inner tooth hole has locking teeth. The prestressed steel bar is locked by the inner tooth hole.

[0012] The end of the prestressed steel bar is accommodated in the internal threaded hole of the sleeve, and an annular space is formed between the prestressed steel bar and the inner wall of the internal threaded hole. The right end of the internal threaded hole is open, and the internal threaded hole can be used for threaded connection with other components or the annular space can be filled with sealing material.

[0013] As an improvement, the outer end of the sleeve is flush with or lower than the outer end surface of the body. The outer end of the sleeve does not protrude from the body, which does not affect the installation of the end plate, pile driving and pile connection.

[0014] The pile body is centrifugally formed or vibrationally formed, and the cross section of the pile body is circular, square, H-shaped or special-shaped.

[0015] Compared with the existing technology, the advantages of this precast concrete component are: the end of the prestressed steel bar is accommodated in the internal threaded hole of the sleeve, so that the tensioning force of each prestressed steel bar in the body is consistent, and the locking force of each prestressed steel bar locked on the sleeve is consistent, so that the bending, shear and pull-out resistance of the body and the end of the precast concrete component are better; an annular space is formed between the prestressed steel bar and the inner wall of the internal threaded hole, and the right end of the internal threaded hole is open, which can be used for mechanical pile connection or connection with other components (such as end plates). At the same time, when the internal threaded hole of the sleeve also serves as a connection hole for mechanical pile connection or connection with other components, there is no need to provide another connection hole on the added end plate. The distribution density of the prestressed steel bars can be increased on a limited body area to produce concrete piles with higher mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a cross-sectional view of an embodiment of a precast concrete component;

[0017] Figure 2A partial cross-sectional view of an embodiment of a precast concrete component;

[0018] Figure 3 is a cross-sectional view of a sleeve in an embodiment of a precast concrete component;

[0019] Figure 4 Schematic diagram of the three-dimensional structure of the clamp in the embodiment of the precast concrete component;

[0020] Figure 5 This is a three-dimensional exploded view of a clamp in an embodiment of a precast concrete component;

[0021] Figure 6 It is a structural schematic diagram of production method 1;

[0022] Figure 7 It is a structural schematic diagram of production method 2;

[0023] Figure 8 This is a schematic structural diagram of production method 2. DETAILED DESCRIPTION

[0024] The present invention will be described in further detail below with reference to the accompanying drawings and embodiments.

[0025] like Figures 1 to 5 FIG. 1 shows a preferred embodiment of a precast concrete component.

[0026] A precast concrete component, which may be a concrete pile or a concrete slab, includes

[0027] The main body 4 and the prestressed steel bars 2 in the main body 4 are preferably steel strands.

[0028] The sleeve 1 has a tapered hole 1a and an internal threaded hole 1b arranged axially in sequence from left to right. The internal threaded hole 1b is located on the right side of the tapered hole 1a. The aperture of the tapered hole 1a gradually increases from left to right. The outer end of the sleeve 1 is flush with or lower than the outer end surface of the body 4.

[0029] The conical clamp 5 is located in the conical hole 1a and its outer peripheral surface is adapted to the conical hole 1a. The center of the clamp 5 has an inner tooth hole 51, and the peripheral wall of the inner tooth hole 51 has a locking tooth 52. The prestressed steel bar 2 is locked by the inner tooth hole 51; the clamp 5 is formed by two or three pieces of clips, and the outer peripheral surface of the clamp 5 forms a conical surface 53 that matches the conical hole 1a.

[0030] The end of the prestressed steel bar 2 is accommodated in the internally threaded hole 1b of the sleeve 1, and an annular space Q is formed between the prestressed steel bar 2 and the inner wall of the internally threaded hole 1b. The right end of the internally threaded hole 1b is open. The internally threaded hole 1b can be used for threaded connection with other components or the annular space Q can be filled with a sealing material. The sealing material can be epoxy resin or concrete.

[0031] The body 4 is centrifugally formed or vibrationally formed, and the cross section of the body 4 is circular, rectangular, H-shaped or special-shaped.

[0032] The left and right directions in this application are based on Figure 1 The directions shown are references and are introduced to facilitate the description of the relative positional relationships of various parts and structures. They do not limit the directions of various parts and components to be fixed. The visual directions may be different in multiple perspectives and scenes, but their relative positional relationships are certain.

[0033] The end of the prestressed steel bar 2 is accommodated in the internal threaded hole 1b of the sleeve 1, so that the tensioning force of each prestressed steel bar 2 in the main body 4 is consistent, and the locking force of each prestressed steel bar 2 locked on the sleeve 1 is consistent, so that the bending, shearing, pulling and other mechanical properties of the main body and the end of the concrete precast component are better; an annular space Q is formed between the prestressed steel bar 2 and the inner wall of the internal threaded hole 1b, and the right end of the internal threaded hole 1b is open, which can be used for mechanical pile connection or connection with other components (such as end plates). At the same time, when the internal threaded hole 1b of the sleeve 1 also serves as a connection hole for mechanical pile connection or connection with other components, there is no need to provide another connection hole on the installed end plate. The distribution density of the prestressed steel bars 2 can be increased on a limited main body area to produce concrete piles with higher mechanical properties.

[0034] The aforementioned prestressed member can be manufactured by the following method.

[0035] Method 1, such as Figure 6 As shown, one mold 8 can produce multiple concrete piles at the same time.

[0036] A locking mechanism is used to lock the prestressed steel bar, which includes a sleeve 1, a tapered clamp 5 and a top tube 6; the sleeve 1 has a tapered hole 1a and an internal threaded hole 1b arranged in sequence from left to right and axially extending therethrough, the internal threaded hole 1b being located on the right side of the tapered hole 1a, and the aperture of the tapered hole 1a gradually expanding from left to right; the tapered clamp 5 can be placed in the tapered hole 1a and its outer circumference is adapted to the tapered hole 1a, the center of the clamp 5 has an internal tooth hole 51 for locking the prestressed steel bar 2, and the peripheral wall of the internal tooth hole 51 has a latching tooth 52; the top tube 6 has an axially extending through-hole 6a, and the outer circumference of the top tube 6 is provided with a top tube external thread 6b for connecting to the internal threaded hole 1b of the sleeve 1;

[0037] A plurality of baffles 3 with through holes 31 and a plurality of prestressed steel bars 2 are distributed on the mold 8, and each top tube 6 is connected to the internal threaded hole 1b of the sleeve 1 through the external thread 6b of the top tube after passing through the through hole 31 of the baffle 3, and each prestressed steel bar 2 is passed through the corresponding tapered hole 1a of the sleeve 1 and the through hole 6a of the top tube 6, and the two ends of each prestressed steel bar 2 are fixed; the prestressed steel bars 2 are tensioned; each top tube 6 is unscrewed from the internal threaded hole 1b of the sleeve 1, and the clamp 5 is installed into the sleeve 1, and then each top tube 6 is screwed into the internal threaded hole 1b of the sleeve 1, the top tube 6 is tightened and the clamp 5 is tightened in the tapered hole 1a of the sleeve 1, and then the sleeve 1, the baffle 3 and the top tube 6 are locked together; after pouring concrete, a concrete precast component is formed; after forming, the prestressed steel bars 2 are tensioned, the top tube 6 is unscrewed, and the baffle 3 is removed. After the prefabricated concrete component is formed, the top cylinder 6 is removed.

[0038] After the precast concrete component is formed, each prestressed steel bar 2 is cut, leaving a section of prestressed steel bar 2 outside the end of the precast component. Then, each prestressed steel bar 2 is tensioned a second time, one by one. The tensioning equipment, such as a tensioning machine or a jack, is conventional and will not be described in detail here. After tensioning is complete, the prestressed steel bar 2 that is exposed at the end of the precast component is cut.

[0039] The sleeve 7 and the baffle 3 can be assembled in such a way that the top cylinder 6 is in a straight cylindrical shape, and a compression nut 7 is threadedly connected to the top cylinder 6 after passing through the through hole of the baffle, so as to press the sleeve 7 and the baffle 3 together.

[0040] The sleeve 7 and the baffle 3 can also be connected in the following manner: the top tube 6 has a connecting portion 61 and a head 62, the connecting portion 61 is a threaded column portion for connecting to the internal threaded hole 1b, the head 62 is polygonal and its outer diameter is larger than the outer diameter of the connecting portion, and the head 62 is used to press the sleeve 7 and the baffle 3 together.

[0041] Method 2, such as Figure 7 As shown, one mold 8 can produce multiple concrete piles at the same time.

[0042] A locking mechanism is used to lock the prestressed steel bar, which includes a sleeve 1, a tapered clamp 5 and a top tube 6; the sleeve 1 has a tapered hole 1a and an internal threaded hole 1b arranged in sequence from left to right and axially extending therethrough, the internal threaded hole 1b being located on the right side of the tapered hole 1a, and the aperture of the tapered hole 1a gradually expanding from left to right; the tapered clamp 5 can be placed in the tapered hole 1a and its outer circumference is adapted to the tapered hole 1a, the center of the clamp 5 has an internal tooth hole 51 for locking the prestressed steel bar 2, and the peripheral wall of the internal tooth hole 51 has a latching tooth 52; the top tube 6 has an axially extending through-hole 6a, and the outer circumference of the top tube 6 is provided with a top tube external thread 6b for connecting to the internal threaded hole 1b of the sleeve 1;

[0043] Two baffles 3 with through holes 31 and multiple prestressed steel bars 2 are distributed on the mold 8, one of the baffles 3 is against the outer end surface of the mold 8, and the other baffle 3 is placed in the mold 8. The outer end of the baffle located in the mold 8 is connected to the tensioning structure. After each top tube 6 passes through the through hole 31 of the baffle 3, it is connected to the internal threaded hole 1b of the sleeve 1 via the top tube external thread 6b. Each prestressed steel bar 2 is passed through the corresponding tapered hole 1a of the sleeve 1 and the through hole 6a of the top tube 6, and the two ends of each prestressed steel bar 2 are fixed; the prestressed steel bar 2 is tensioned; each top tube 6 is unscrewed from the internal threaded hole 1b of the sleeve 1, the clamp 5 is installed into the sleeve 1, and each top tube 6 is screwed into the internal threaded hole 1b of the sleeve 1. The top tube 6 is tightened and the clamp 5 is pressed tightly into the tapered hole 1a of the sleeve 1, and the sleeve 1, baffle 3 and top tube 6 are locked together; concrete is poured to form a precast concrete component; after forming, the prestressed steel bar 2 is tensioned, the top tube 6 is unscrewed, and the baffle 3 is removed. After the precast concrete component is formed, the top tube 6 is removed for reuse.

[0044] The sleeve 7 and the baffle 3 are assembled in the following manner: the top cylinder 6 is in a straight cylindrical shape, and a compression nut 7 is threadedly connected to the top cylinder 6 after passing through the through hole of the baffle, so as to press the sleeve 7 and the baffle 3 together.

[0045] Method 3, such as Figure 8 As shown, the difference from method 2 is that the top cylinder 6 has a connecting portion 61 and a head 62, the connecting portion 61 is a threaded column portion for connecting to the internal threaded hole 1b, the head 62 is polygonal and its outer diameter is larger than the outer diameter of the connecting portion, and the head 62 is used to press the sleeve 7 and the baffle 3 together.

[0046] It should be noted that in the description of this embodiment, the terms "front, back", "left, right", "inside, outside", "upper, lower" and the like indicating directions or positional relationships are all based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or component referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they cannot be understood as limitations on the present invention. The terms "install", "connect", and "connected" should be understood in a broad sense. For example, they can be fixed connections, detachable connections, or integral connections; they can be directly connected, or indirectly connected through an intermediate medium, or they can be internal connections between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

Claims

1. A precast concrete component comprising a body (4) and prestressed steel bars (2) in the body (4), characterized in that: Also includes A sleeve (1), wherein the sleeve (1) has a tapered hole (1a) and an internal threaded hole (1b) arranged axially in sequence from left to right, the internal threaded hole (1b) is located on the right side of the tapered hole (1a), and the diameter of the tapered hole (1a) gradually increases from left to right; A conical clamp (5) is located in the conical hole (1a) and its outer peripheral surface is adapted to the conical hole (1a). The center of the clamp (5) has an inner tooth hole (51), and the peripheral wall of the inner tooth hole (51) has locking teeth (52). The prestressed steel bar (2) is locked by the inner tooth hole (51); The end of the prestressed steel bar (2) is accommodated in the internal threaded hole (1b) of the sleeve (1), and an annular space (Q) is formed between the prestressed steel bar (2) and the inner wall of the internal threaded hole (1b). The right end of the internal threaded hole (1b) is open. The internal threaded hole (1b) can be used for threaded connection with other components or the annular space (Q) can be filled with sealing material.

2. The precast concrete component according to claim 1, characterized in that: The outer end of the sleeve (1) is flush with or lower than the outer end surface of the body (4).

3. The precast concrete component according to claim 1, characterized in that: The body (4) is centrifugally formed or vibrationally formed, and the cross section of the body (4) is circular, rectangular, H-shaped or special-shaped.

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