Mechanical connection prestressed concrete precast pile with end plates and construction method

Abstract

The invention discloses a mechanical connection prestressed concrete precast pile with an end plate and a construction method.The mechanical connection prestressed concrete precast pile with the end plate comprises a prestressed steel bar, a concrete pile body, the end plate and a mechanical connecting piece, and the mechanical connecting piece comprises a sleeve assembly, a lining, an inserting rod and a plurality of occlusion petals; the sleeve assembly comprises a first sleeve and a second sleeve, and the first sleeve and the second sleeve between the adjacent mechanically-connected prestressed concrete precast piles with the end plates are connected through an inserting rod to achieve mechanical connection between the adjacent precast piles. According to the mechanically-connected prestressed concrete precast pile with the end plates and the construction method, the strength of the pile head of the precast pile can be guaranteed, meanwhile, connection and positioning between piles are more accurate, the stress concentration phenomenon does not exist in the connection position, and the small strain detection qualification rate is higher.

Description

Technical Field

[0001] The present invention relates to the technical field of precast piles, and in particular to a mechanically connected prestressed concrete precast pile with an end plate and a construction method. Background Art

[0002] Precast concrete piles, with their advantages of high structural strength and efficient construction, are widely used in building foundations. Building pile foundation design requires a deep foundation depth to ensure superstructure stability. A single precast pile is often too long to reach the specified depth, necessitating the use of multiple piles connected end-to-end and driven down to the desired depth.

[0003] Precast concrete piles can be divided into two types according to the pile head structure: precast piles with end plates and precast piles without end plates. These two structures each have their own advantages and disadvantages. The advantage of precast piles with end plates is that the pile heads are strong and not easy to break during construction, and the end plates disperse the stress at the joints, avoiding stress concentration. In addition, adjacent pile heads are connected by welding the end plates, which is a simple process. The main disadvantage is that the welding process has high environmental requirements and the welds are easily corroded. The advantage of precast piles without end plates is that they are connected by mechanical connectors, which is simple to operate, has low construction environment requirements and better corrosion resistance. Precast piles connected by mechanical connectors are more directly stressed and have less deformation. The disadvantage of precast piles without end plates is that there are gaps after the mechanical connectors are connected, which easily produces reflections during small strain detection, resulting in unqualified detection. In addition, due to the lack of end plate protection, the pile head concrete is more easily damaged. Summary of the Invention

[0004] In view of the different shortcomings of precast piles with end plates and precast piles without end plates, the present invention proposes a mechanically connected prestressed concrete precast pile with end plates. By arranging a mechanical connection structure on the end plate, the strength of the precast pile head is ensured, the connection positioning between the piles is more accurate, there is no stress concentration at the connection position, and the small strain detection pass rate is higher.

[0005] The present invention is achieved through the following technical solutions: A mechanically connected prestressed concrete precast pile with end plates, comprising prestressed steel bars, a concrete pile body, end plates, and mechanical connectors, wherein the prestressed steel bars are arranged in the concrete pile body, and the end plates are arranged at both ends of the concrete pile body; The mechanical connector includes a sleeve assembly, a bushing, an insertion rod and a plurality of bite flaps, the sleeve assembly includes a first sleeve and a second sleeve, and the first sleeve and the second sleeve are both sleeves with one end open; A bushing is provided at the open end of the first sleeve, and a plurality of bite flaps are provided in the internal space formed by the bushing and the first sleeve, a compression spring is provided between the bite flap and the inner cavity end surface of the first sleeve, and an insertion rod is provided at the open end of the second sleeve for plugging and cooperating with the plurality of bite flaps; the plurality of bite flaps are fitted together to form a hollow cylindrical structure, and have an outer cylindrical surface, the outer cylindrical surface is provided with a spiral groove, and the spiral groove is provided with a coil spring; the coil spring is used to fit and connect the plurality of bite flaps, on the one hand to avoid the plurality of bite flaps from being independent and scattered, and on the other hand to limit the mobility of the plurality of bite flaps along the central axis direction to avoid misalignment between the bite flaps, and the spiral groove is used to prevent the coil spring from sliding off the plurality of bite flaps, thereby ensuring the connection stability between the two and effectively improving the tightening effect of the plurality of bite flaps.

[0006] The insertion rod includes an insertion section and a fixed section, the fixed section is inserted into the open end of the second sleeve and fixedly connected to the second sleeve; the outer surface of the insertion section is provided with plug-in teeth, and the inner surface of the hollow column composed of the multiple occlusal petals is provided with occlusal tooth grooves corresponding to the plug-in teeth; after the insertion rod is inserted, the plug-in teeth are embedded in the occlusal tooth grooves to prevent the insertion rod from falling out.

[0007] The method of using the mechanical connector is that before connection, the compression spring, the multiple bite petals on which the coil spring is mounted, and the bushing are sequentially installed into the first sleeve, and the insertion rod is installed into the second sleeve. When connecting, the second sleeve with the insertion rod is moved toward the first sleeve, and the insertion rod passes through the bushing and pushes the multiple bite petals. The bite petals move as the insertion rod is inserted and squeeze the compression spring. At the same time, the multiple bite petals separate, causing the enclosed hollow cylindrical space to become larger, making it easier to insert the insertion rod. After the insertion rod is fully inserted, under the joint action of the compression spring and the coil spring, the multiple bite petals move toward the bushing again and tightly wrap the insertion rod.

[0008] The end plate is provided with a through hole; the through hole is used for installing the first sleeve and the second sleeve.

[0009] One end of the prestressed steel bar is connected to the unopened end of the first sleeve, the first sleeve passes through the through hole of the end plate and is fixedly connected to the end plate, the open end of the first sleeve is flush with the outer surface of the end plate, the other end of the prestressed steel bar is connected to the unopened end of the second sleeve, the second sleeve is inserted into the through hole of the end plate and is fixedly connected to the end plate.

[0010] As a further improvement of the present invention, the end surface of the bushing facing the opening direction of the first sleeve is provided with circumferentially uniformly distributed stress grooves; when installing the bushing to the first sleeve, a tool can be inserted into the stress grooves to facilitate bushing installation.

[0011] The pitch of the spiral groove is equal to the pitch of the coil spring in a natural state.

[0012] Designing the pitch of the spiral groove to be equal to the pitch of the coil spring in its natural state can prevent the coil spring from being in an axial compression state for a long time, which will affect the life of the coil spring.

[0013] As a further improvement of the present invention, the open end of the second sleeve passes through the outer surface of the end plate; The open end of the second sleeve is provided with an embedded ring edge, and the open end of the first sleeve is provided with an embedded ring groove for the embedded ring edge to be embedded in. Through the cooperation of the embedded ring edge and the embedded ring groove, the first sleeve and the second sleeve can be embedded in each other, thereby improving the bending resistance of the connection point.

[0014] As a further improvement of the present invention, the open end of the second sleeve is flush with the outer surface of the end plate; The insertion rod is further provided with a limiting section between the insertion section and the fixing section. The limiting section is in a frustum shape, with an end with a smaller frustum radius connected to the insertion section and an end with a larger frustum radius connected to the fixing section. After the insertion rod is connected to the second sleeve through the fixing section, the end surface of the limiting section with the larger frustum radius abuts against the second sleeve. The inner wall of the open end of the first sleeve is provided with a tapered section corresponding to the stopper section. When the rod is inserted into the first sleeve, the insertion section is completely embedded in the first sleeve. The open end of the second sleeve is flush with the outer surface of the end plate, ensuring that the edge of the second sleeve will not be bumped or deformed due to exposure during transportation. By embedding the stopper section of the rod into the tapered section of the first sleeve, the rod and the first sleeve can be interlocked, improving the bending resistance of the connection point.

[0015] As a further improvement of the present invention, the first sleeve and the second sleeve are fixed to the through hole by threaded connection or welding.

[0016] As a further improvement of the present invention, the outer surfaces of the first sleeve and the second sleeve are both provided with discontinuous bosses, and the opening of the through hole facing the side of the concrete pile body is provided with a discontinuous flange corresponding to the bosses. When the first sleeve and the second sleeve are connected to the end plate, the flange blocks the bosses, so that the first sleeve and the second sleeve are connected to the through hole to form a platform edge.

[0017] As a further improvement of the present invention, it further comprises an anchoring steel bar, one end of which is fixedly connected to the end plate, and the other end of which is inserted into the concrete pile body.

[0018] As a further improvement of the present invention, the cross-section of the concrete pile body is circular or square.

[0019] As a further improvement of the present invention, the concrete pile body is a solid pile body or a hollow pile body.

[0020] The present invention also provides a construction method for mechanically connected prestressed concrete precast piles with end plates, which uses the mechanically connected prestressed concrete precast piles with end plates, comprising the following steps: S1: constructing a first mechanically connected prestressed concrete precast pile with an end plate at a preset position of the pile to a connection position, with the first sleeve facing upward; S2: sequentially installing the compression spring, the multiple bite petals of the coil spring, and the bushing in the first sleeve of the first mechanically connected prestressed concrete precast pile with an end plate; S3: Installing the plunger in a second sleeve of a second mechanically connected prestressed concrete precast pile with an end plate; S4: hoisting the second mechanically connected prestressed concrete precast pile with an end plate above the first mechanically connected prestressed concrete precast pile with an end plate, with the second sleeve facing downward; S5: lowering the second mechanically connected prestressed concrete precast pile with an end plate so that the plunger is inserted into the first sleeve of the first mechanically connected prestressed concrete precast pile with an end plate to complete the mechanical connection; S6: Weld and fix the edges of the two end plates at the connection.

[0021] S7: Continue to construct the second mechanically connected prestressed concrete precast pile with an end plate, and repeat steps S2 to S6 until the pile foundation construction is completed.

[0022] Compared with the existing technology, the beneficial effects of the present invention are: the end plate protects the pile head of the concrete pile body and can be used as a positioning reference for the connection, ensuring that the mechanical connector is not displaced during construction. At the same time, the prestressed steel bars are directly connected through the connector, the force is more direct and the deformation is smaller, the corrosion resistance of the prestressed steel bar connection position is guaranteed, and stress concentration will not occur at the connection position, and the small strain detection pass rate is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following is a brief introduction to the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 This is an overall structural diagram of a mechanically connected prestressed concrete precast pile with end plates according to the present invention; Figure 2Schematic diagram of the end plate connection of the mechanically connected prestressed concrete precast piles with end plates according to the present invention; Figure 3 Schematic diagram of the connection method of the first embodiment of the mechanically connected prestressed concrete precast piles with end plates of the present invention; Figure 4 1. It is an exploded view of the mechanical connector of the first embodiment of the mechanically connected prestressed concrete precast piles with end plates according to the present invention; Figure 5 Schematic diagram of the assembly of multiple interlocking petals of mechanically connected prestressed concrete precast piles with end plates according to the present invention; Figure 6 Schematic diagram of a single interlocking petal structure of a mechanically connected prestressed concrete precast pile with an end plate according to the present invention; Figure 7 It is a schematic diagram of the installation of a bushing and a plurality of interlocking petals of a mechanically connected prestressed concrete precast pile with an end plate according to the present invention; Figure 8 1. It is a schematic diagram of the rod insertion structure of the first embodiment of the mechanically connected prestressed concrete precast pile with end plates of the present invention; Figure 9 Schematic diagram of the threaded connection between the first sleeve and the through hole of the first embodiment of the mechanically connected prestressed concrete precast pile with end plates of the present invention; Figure 10 Schematic diagram of the welding connection between the first sleeve and the through hole of another embodiment of the mechanically connected prestressed concrete precast pile with end plates of the present invention; Figure 11 Schematic diagram of the installation of anchor steel bars for mechanically connected prestressed concrete precast piles with end plates according to the present invention; Figure 12 is a cross-sectional view of a first sleeve of a first embodiment of a mechanically connected prestressed concrete precast pile with an end plate according to the present invention; Figure 13 This is a schematic diagram of the installation method of mechanically connected prestressed concrete precast piles with end plates; Figure 14 Schematic diagram of the connection method of the second embodiment of the mechanically connected prestressed concrete precast piles with end plates of the present invention; Figure 15 1. It is an exploded view of the mechanical connector of the second embodiment of the mechanically connected prestressed concrete precast piles with end plates according to the present invention; Figure 16 2. It is a schematic diagram of the rod insertion structure of the second embodiment of the mechanically connected prestressed concrete precast pile with end plates of the present invention; Figure 17 Schematic diagram of the connection between the limiting portion of the plunger and the first sleeve of the second embodiment of the mechanically connected prestressed concrete precast pile with end plates of the present invention; Figure 183D schematic diagram of a third embodiment of a mechanically connected prestressed concrete precast pile with an end plate according to the present invention, showing a first sleeve and a through hole connected to each other via a boss and a flange; Figure 19 Schematic diagram of the connection between the first sleeve and the through-hole platform edge of the third embodiment of the mechanically connected prestressed concrete precast pile with end plates of the present invention; Figure 20 It is a schematic diagram of the stress groove on the surface of the bushing of the mechanically connected prestressed concrete precast pile with end plates of the present invention.

[0025] Figure 21 It is a structural schematic diagram of a compression spring of a mechanically connected prestressed concrete precast pile with an end plate according to the present invention. DETAILED DESCRIPTION

[0026] The following will provide a clear and complete description of the technical solutions of various embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0027] The present invention will be further described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0028] First embodiment: A mechanically connected prestressed concrete precast pile with end plates includes prestressed steel bars 1, a concrete pile body 2, end plates 3 and mechanical connectors. The prestressed steel bars 1 are arranged in the concrete pile body 2, and the end plates 3 are arranged at both ends of the concrete pile body 2.

[0029] The mechanical connector includes a sleeve assembly, a bushing 4, an insertion rod 5 and four bite flaps 6. The sleeve assembly includes a first sleeve 7 and a second sleeve 8. The first sleeve 7 and the second sleeve 8 are both sleeves with one end open.

[0030] A bushing 4 is provided at the open end of the first sleeve 7. The bushing 4 is threadedly connected to the inner wall of the first sleeve 7. Four snap-fitting petals 6 are provided in the internal space formed by the bushing 4 and the first sleeve 7. A compression spring 9 is provided between the snap-fitting petals 6 and the inner end surface of the first sleeve 7. The open end of the second sleeve 8 is provided with an insertion rod 5 that plugs into and mates with the four snap-fitting petals 6. The four snap-fitting petals 6 fit together to form a hollow cylindrical structure and have an outer cylindrical surface 10. The outer cylindrical surface 10 is provided with a spiral groove 12. The spiral groove 12 is provided with a coil spring 13. The coil spring 13 is used to fit and connect the four snap-fitting petals 6. On the one hand, it prevents the four snap-fitting petals 6 from being scattered independently. On the other hand, it limits the mobility of the four snap-fitting petals 6 along the central axis to prevent misalignment between the snap-fitting petals 6. The spiral groove 12 is used to prevent the coil spring 13 from sliding off the four snap-fitting petals 6, ensuring the stability of the connection between the two and effectively improving the tightening effect of the four snap-fitting petals 6. In order to further prevent the coil spring 13 from being separated from the bite flap 6 , one end of the coil spring 13 may be fixed to the bite flap 6 by welding.

[0031] The insertion rod 5 includes an insertion section 14 and a fixing section 15. The fixing section 15 is inserted into the open end of the second sleeve 8 and threadedly connected to the second sleeve 8. After connection, the fixing section 15 is lower than the end surface of the open end of the second sleeve 8. The outer surface of the insertion section 14 is provided with insertion teeth 16. The inner surface of the hollow column formed by the four engaging petals 6 is provided with engaging tooth grooves 17 corresponding to the insertion teeth 16. After the insertion rod 5 is inserted, the insertion teeth 16 are embedded in the engaging tooth grooves 17, preventing the insertion rod 5 from being dislodged.

[0032] The method of using the mechanical connector is to install the compression spring 9, the four bite petals 6 with the coil spring 13 and the bushing 4 into the first sleeve 7 in sequence before connection, and install the insertion rod 5 into the second sleeve 8. When connecting, the second sleeve 8 with the insertion rod 5 is moved toward the first sleeve 7, and the insertion rod 5 passes through the bushing 4 and pushes the four bite petals 6. The bite petals 6 move with the insertion of the insertion rod 5 and squeeze the compression spring 9. At the same time, the four bite petals 6 separate, causing the hollow cylindrical space enclosed to become larger, making it easier for the insertion of the insertion rod 5. After the insertion rod 5 is fully inserted, the four bite petals 6 move back toward the bushing 4 under the joint action of the compression spring 9 and the coil spring 13 and tightly wrap the insertion rod 5. At this time, the plug-in teeth 16 are embedded in the bite tooth grooves 17. In order to ensure that the compression spring 9 is subjected to uniform force, the two ends of the compression spring 9 are processed into circular rings to make the end of the compression spring 9 more evenly stressed, and not easy to slip or bend during compression. The structure of the compression spring 9 is as follows: Figure 21 shown.

[0033] The end plate 3 is provided with a through hole 19 for mounting the first sleeve 7 and the second sleeve 8; One end of the prestressed steel bar 1 is connected to the unopened end of the first sleeve 7, the first sleeve 7 passes through the through hole 19 of the end plate 3 and is fixedly connected to the end plate 3, the open end of the first sleeve 7 is flush with the outer surface of the end plate 3, and the other end of the prestressed steel bar 1 is connected to the unopened end of the second sleeve 8, the second sleeve 8 is inserted into the through hole 19 of the end plate 3 and is fixedly connected to the end plate 3.

[0034] The end surface of the bushing 4 facing the opening of the first sleeve 7 is provided with four force-bearing grooves 31 evenly distributed around the circumference. When installing the bushing 4 into the first sleeve 7, a tool can be inserted into the force-bearing grooves 31 to facilitate installation of the bushing 4. In this embodiment, the bushing 4 is threadedly connected to the first sleeve 7, so the bushing 4 can be screwed through the force-bearing grooves 31 to be installed in the first sleeve 7.

[0035] In this embodiment, the depth of the spiral groove 12 is greater than or equal to the cross-sectional diameter of the coil spring 13. The outer surface of the occlusal flap 6 corresponding to the end of the spiral groove 12 is spot-welded to the end of the coil spring 13. After one end of the coil spring 13 is welded to the occlusal flap, when the occlusal flap is separated, the coil spring 13 deforms because one end is fixed, but it does not escape from the spiral groove 12 or move relative to the occlusal flap 6.

[0036] In this embodiment, the pitch of the spiral groove 12 is designed to be equal to the pitch of the coil spring 13 in its natural state, which can prevent the coil spring 13 from being in an axially compressed state for a long time, thereby reducing the life of the coil spring 13.

[0037] In this embodiment, the open end of the second sleeve 8 extends beyond the outer surface of the end plate 3. An embedded rim 22 is provided at the open end of the second sleeve 8, and an embedded groove 23 is provided at the open end of the first sleeve 7 for engagement with the embedded rim 22. The fit between the embedded rim 22 and the embedded groove 23 allows the first sleeve 7 and the second sleeve 8 to engage with each other, thereby improving the bending resistance of the connection point.

[0038] In this embodiment, the first sleeve 7 and the second sleeve 8 are fixed to the through hole 19 by threaded connection, as shown in FIG. Figure 9 As shown, in other embodiments, the first sleeve 7 and the second sleeve 8 can also be fixed to the through hole 19 by welding, such as Figure 10 As shown, the edges of the through hole 19 are welded to the edges of the first sleeve 7 and the second sleeve 8 on the inner and outer sides of the end plate 3 respectively. Figure 9 、 Figure 10 In the figure, only the connection between the first sleeve 7 and the through hole 19 is taken as an example.

[0039] In this embodiment, anchoring steel bars 24 are further provided between the concrete pile body 2 and the end plate 3. The anchoring steel bars 24 are evenly arranged around the circumference. One end of the anchoring steel bar 24 is fixedly connected to the end plate 3, and the other end is inserted into the concrete pile body 2. The anchoring steel bars 24 can improve the connection strength between the concrete pile body 2 and the end plate 3. In this embodiment, the number of anchoring steel bars 24 is eight.

[0040] In this embodiment, the concrete pile body 2 is a hollow pile with a circular cross section, the prestressed steel bar 1 is arranged in the concrete pile body 2, and the end plates 3 on both sides are annular and retain 12 through holes 19, the same number as the prestressed steel bars 1, and are arranged circumferentially according to the arrangement of the prestressed steel bars 1, as shown in FIG. Figure 1 shown.

[0041] In other embodiments, the cross-section of the concrete pile body 2 may also be set to be square or other shapes.

[0042] In other embodiments, the concrete pile body 2 may also be configured as a solid pile body.

[0043] In other embodiments, the concrete pile body 2 may also be designed as a special-shaped pile body with a variable cross-section or a pile body with a uniform cross-section.

[0044] The construction method of the mechanically connected prestressed concrete precast piles with end plates of this embodiment comprises the following steps: S1: The first mechanically connected prestressed concrete precast pile 29 with an end plate is constructed at a preset position of the pile to a connection position, with the first sleeve 7 facing upwards; S2: sequentially installing the compression spring 9, the plurality of bite petals 6 sleeved with the coil spring 13, and the bushing 4 in the first sleeve 7 of the first mechanically connected prestressed concrete precast pile 29 with an end plate; S3: Installing the plunger 5 in the second sleeve 8 of the second mechanically connected prestressed concrete precast pile 30 with an end plate; S4: hoisting the second mechanically connected prestressed concrete precast pile 30 with an end plate with the second sleeve 8 facing downward to the top of the first mechanically connected prestressed concrete precast pile 29 with an end plate; S5: Lowering the second mechanically connected prestressed concrete precast pile 30 with an end plate so that the insertion rod 5 is inserted into the first sleeve 7 of the first mechanically connected prestressed concrete precast pile 29 with an end plate to complete the mechanical connection; S6: Weld and fix the edges of the two end plates 3 at the connection.

[0045] S7: Continue to construct the second mechanically connected prestressed concrete precast pile 30 with an end plate, and repeat steps S2 to S6 until the pile foundation construction is completed.

[0046] Second embodiment: The difference between this embodiment and the first embodiment is that the open end of the second sleeve 8 is flush with the outer surface of the end plate 3; The insertion rod 5 is further provided with a limiting section 25 between the insertion section 14 and the fixed section 15. The limiting section 25 is in the shape of a truncated cone, with the end with a smaller radius of the truncated cone connected to the insertion section 14, and the end with a larger radius of the truncated cone connected to the fixed section 15. After the insertion rod 5 is connected to the second sleeve 8 through the fixed section 15, the end face of the limiting section 25 with a larger radius of the truncated cone abuts against the second sleeve 8.

[0047] The inner wall of the open end of the first sleeve 7 is provided with a tapered section 26 corresponding to the stopper section 25. When the insertion rod 5 is inserted into the first sleeve 7, the insertion section 14 is completely embedded in the first sleeve 7. The open end of the second sleeve 8 is flush with the outer surface of the end plate 3, ensuring that the edge of the second sleeve 8 will not deform due to bumps during transportation. By embedding the stopper section 25 of the insertion rod 5 into the tapered section 26 of the first sleeve 7, the insertion rod 5 and the first sleeve 7 are interlocked, improving the bending resistance of the connection point.

[0048] Third embodiment: This embodiment differs from the first embodiment in that the outer surfaces of the first sleeve 7 and the second sleeve 8 are each provided with a discontinuous boss 27, and the opening of the through hole 19 facing the concrete pile body 2 is provided with a discontinuous flange 28 corresponding to the boss 27. When the first sleeve 7 and the second sleeve 8 are connected to the end plate 3, the flange 28 blocks the boss 27, so that the first sleeve 7 and the second sleeve 8 are connected to the through hole 19 in a boss-edge connection. When the first sleeve 7 and the second sleeve 8 are connected to the end plate 3, the first sleeve 7 or the second sleeve 8 is rotated to allow the boss 27 to pass through the gap between the discontinuous flanges 28 and then the first sleeve 7 or the second sleeve 8 is rotated again to allow the boss 27 to overlap with the flange 28, completing the installation. Figure 19 In the figure, only the connection between the first sleeve 7 and the through hole 19 is used as an illustration.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the technical solutions of the embodiments of the present invention.

Claims

1. A mechanically connected prestressed concrete precast pile with an end plate, comprising prestressed steel bars, a concrete pile body, an end plate, and a mechanical connector, characterized in that: The prestressed steel bars are arranged in the concrete pile body, and the end plates are arranged at both ends of the concrete pile body; The mechanical connector includes a sleeve assembly, a bushing, an insertion rod and a plurality of bite flaps, the sleeve assembly includes a first sleeve and a second sleeve, and the first sleeve and the second sleeve are both sleeves with one end open; A bushing is provided at the open end of the first sleeve, a plurality of bite flaps are provided in the internal space formed by the bushing and the first sleeve, a compression spring is provided between the bite flap and the inner cavity end surface of the first sleeve, and an insertion rod is provided at the open end of the second sleeve for plugging and cooperating with the plurality of bite flaps; The plurality of occlusal flaps are fitted together to form a hollow cylindrical structure having an outer cylindrical surface, the outer cylindrical surface is provided with a spiral groove, and a spiral spring is provided in the spiral groove; The insertion rod includes an insertion section and a fixing section, wherein the fixing section is inserted into the open end of the second sleeve and fixedly connected to the second sleeve; The outer surface of the insertion section is provided with plug-in teeth, and the inner surface of the hollow column formed by the multiple occlusal petals is provided with occlusal tooth grooves corresponding to the plug-in teeth; The end plate is provided with a through hole; One end of the prestressed steel bar is connected to the unopened end of the first sleeve, the first sleeve passes through the through hole of the end plate and is fixedly connected to the end plate, the open end of the first sleeve is flush with the outer surface of the end plate, the other end of the prestressed steel bar is connected to the unopened end of the second sleeve, the second sleeve is inserted into the through hole of the end plate and is fixedly connected to the end plate.

2. The mechanically connected prestressed concrete precast pile with end plates according to claim 1, characterized in that: The end surface of the bushing facing the opening direction of the first sleeve is provided with circumferentially uniformly distributed stress-bearing grooves; The pitch of the spiral groove is equal to the pitch of the coil spring in a natural state.

3. The mechanically connected prestressed concrete precast pile with end plates according to claim 1, characterized in that: The open end of the second sleeve passes through the outer surface of the end plate; The open end of the second sleeve is provided with an embedded ring edge, and the open end of the first sleeve is provided with an embedded ring groove for the embedded ring edge to be embedded.

4. The mechanically connected prestressed concrete precast pile with end plates according to claim 1, characterized in that: The open end of the second sleeve is flush with the outer surface of the end plate; The insertion rod is further provided with a limiting section between the insertion section and the fixing section. The limiting section is in a frustum shape, with an end with a smaller frustum radius connected to the insertion section and an end with a larger frustum radius connected to the fixing section. After the insertion rod is connected to the second sleeve through the fixing section, the end surface of the limiting section with the larger frustum radius abuts against the second sleeve. The inner wall of the open end of the first sleeve is provided with a conical surface section corresponding to the limiting section. When the insertion rod is inserted into the first sleeve, the insertion section is completely embedded in the first sleeve.

5. The mechanically connected prestressed concrete precast pile with end plates according to claim 1, characterized in that: The first sleeve and the second sleeve are fixed to the through hole by threaded connection or welding.

6. The mechanically connected prestressed concrete precast pile with end plates according to claim 1, characterized in that: The outer surfaces of the first sleeve and the second sleeve are both provided with discontinuous bosses, and the opening of the through hole facing the concrete pile body is provided with a discontinuous flange corresponding to the bosses. When the first sleeve and the second sleeve are connected to the end plate, the flange blocks the bosses, so that the first sleeve and the second sleeve are connected to the through hole to form a platform edge.

7. A mechanically connected prestressed concrete precast pile with end plates according to any one of claims 1 to 6, characterized in that: It also includes an anchoring steel bar, one end of which is fixedly connected to the end plate, and the other end of which is inserted into the concrete pile body.

8. The mechanically connected prestressed concrete precast pile with end plates according to claim 1, characterized in that: The cross section of the concrete pile body is circular or square.

9. The mechanically connected prestressed concrete precast pile with end plates according to claim 1, characterized in that: The concrete pile body is a solid pile body or a hollow pile body.

10. A construction method for mechanically connected prestressed concrete precast piles with end plates, characterized by: A mechanically connected prestressed concrete precast pile with an end plate as claimed in any one of claims 1 to 9 is used, comprising the following steps: S1: constructing a first mechanically connected prestressed concrete precast pile with an end plate at a preset position of the pile to a connection position, with the first sleeve facing upward; S2: sequentially installing the compression spring, the multiple bite petals of the coil spring, and the bushing in the first sleeve of the first mechanically connected prestressed concrete precast pile with an end plate; S3: Installing the plunger in a second sleeve of a second mechanically connected prestressed concrete precast pile with an end plate; S4: hoisting the second mechanically connected prestressed concrete precast pile with an end plate above the first mechanically connected prestressed concrete precast pile with an end plate, with the second sleeve facing downward; S5: lowering the second mechanically connected prestressed concrete precast pile with an end plate so that the plunger is inserted into the first sleeve of the first mechanically connected prestressed concrete precast pile with an end plate to complete the mechanical connection; S6: Weld and fix the edges of the two end plates at the connection; S7: Continue to construct the second mechanically connected prestressed concrete precast pile with an end plate, and repeat steps S2 to S6 until the pile foundation construction is completed.

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