A beam-slab and pipe pile connecting structure for fabricated structure

Abstract

This utility model relates to the field of mixing device technology, specifically to a prefabricated beam-slab and pipe pile connection structure, including a pipe pile and an outer steel pipe fixedly fitted over the pipe pile. A reinforcing cage is provided inside both the outer steel pipe and the pipe pile, with the upper end of the reinforcing cage connected to the beam-slab above the outer steel pipe. It also includes expansion rings. The outer steel pipe between the pipe pile and the beam-slab forms a receiving cavity, with expansion rings located in the upper, middle, and lower parts of the cavity. Each expansion ring is fitted and fixed to the reinforcing bars on the outside of the reinforcing cage. The thickness of the expansion ring gradually increases from the outer ring to the inner ring, and there is a gap between the outer ring surface of the expansion ring and the inner wall of the outer steel pipe. The expansion ring has a ring array of through holes penetrating both the upper and lower surfaces. This utility model solves the problem of shrinkage of the core-filling concrete injected into the outer steel pipe connecting the beam-slab and pipe pile, which affects the support strength of the connection node.

Description

Technical Field

[0001] This utility model relates to the field of bridge construction technology, specifically to a prefabricated beam-slab and pipe pile connection structure. Background Technology

[0002] The connection structure between beams / slabs and pipe piles is a key node connecting pile foundation engineering with the superstructure. Its core function is to reliably transfer the load from the beams / slabs to the pipe piles, and then from the pipe piles to the foundation, while ensuring the integrity, stability, and durability of the structure. For example, the authorization announcement number CN218540359U, "A Precast Pipe Pile Top Beam-Slab Structure," provides a prefabricated sheet pile connection node. During the construction of this structure, the core-filling concrete needs to be grouted into the outer steel pipe and the pipe pile. In the connection between pipe piles and beams, the outer steel pipe and its internal filler concrete form a direct force transmission path. All loads from the bridge superstructure act directly on the filler concrete at the top of the outer steel pipe through the beam, creating a significant stress concentration area. The concrete in this area needs to effectively transfer the pressure to the pipe piles below and the surrounding soil. Shrinkage gaps or inadequate bonding in this area will severely affect the stiffness and bearing capacity of the joint; therefore, it is necessary to address the issue of concrete shrinkage within the outer steel pipe affecting the support strength of the joint. Utility Model Content

[0003] This invention addresses the problem of shrinkage of the core concrete injected into the outer steel pipe connecting beams and pipe piles, which affects the support strength of the connection node. It provides a prefabricated beam-slab and pipe pile connection structure that can compensate for the shrinkage of the core concrete inside the outer steel pipe.

[0004] To solve the above problems, the technical solution of this utility model is: A prefabricated beam-slab and pipe pile connection structure includes a pipe pile and an outer steel pipe fixedly fitted over the pipe pile. A reinforcing cage is provided inside both the outer steel pipe and the pipe pile. The upper end of the reinforcing cage is connected to the beam-slab on the upper side of the outer steel pipe. It also includes expansion rings. The outer steel pipe between the pipe pile and the beam-slab is a receiving cavity. Expansion rings are provided in the upper, middle and lower parts of the receiving cavity. Each expansion ring is fitted and fixed on the reinforcing bars on the outside of the reinforcing cage. The thickness of the expansion ring gradually increases from the outer ring to the inner ring. There is a gap between the outer ring surface of the expansion ring and the inner wall of the outer steel pipe. Through holes penetrating the upper and lower surfaces of the expansion ring are arranged in a ring array on the expansion ring.

[0005] Furthermore, the expansion ring is a circular ring made of micro-expansion concrete, and the expansion ring is detachably connected by connecting half rings that are symmetrical front and rear.

[0006] Furthermore, the top two ends of the connecting half-ring are connected to a connecting plate one, and the bottom two ends are connected to a connecting plate two. The connecting plate one is a right-angled triangular plate, and the inclined surface of the connecting plate one is connected to the top surface of the connecting half-ring. The ends of the two connecting half-rings are in contact with each other, and the connecting plates one on the same side of the top surfaces of the two connecting half-rings are in contact with each other. The connecting plates one on the same side are penetrated by a bolt one, and the end of the bolt one is limited by a nut one. The connecting plates two on the same side of the bottom surfaces of the two connecting half-rings are in contact with each other, and the connecting plates two on the same side are penetrated by a bolt two, and the end of the bolt one is limited by a nut two.

[0007] Furthermore, the connecting plates one and two on the same side of each connecting half-ring are symmetrical, with one straight surface of the connecting plate one being flush with the outer ring of the connecting half-ring and the other straight surface being flush with the upper end of the connecting half-ring.

[0008] Furthermore, each of the connecting half-rings has an arc-shaped groove recessed on its inner ring surface. The ends of the grooves on the two connecting half-rings on the expansion ring contact each other, forming a circular groove that snaps onto the corresponding rib of the expansion ring.

[0009] Furthermore, the distance between the outer ring of the expansion ring and the outer steel pipe is 5-15mm, and the inner diameter of the expansion ring matches the inner diameter of the surrounding reinforcement.

[0010] The beneficial effects of this utility model through the above technical solution are as follows: This invention features expansion rings positioned at the top, middle, and bottom of the outer steel pipe between the pipe pile and the beam / slab. These rings expand by absorbing water during the pouring of the core-filling concrete, transforming the expansion stress into radial compressive stress. This compresses the outer steel pipe outwards and the reinforcing cage and its internal concrete inwards, significantly reducing the shrinkage gap between the core-filling concrete and the inner wall of the outer steel pipe. Furthermore, it generates beneficial self-prestress within the core-filling concrete. The through-holes on the expansion rings ensure the flow and venting of the core-filling concrete. After solidification, the core-filling concrete within the holes forms a "pin" anchor, enhancing the bond and shear strength between the expansion rings and the core-filling concrete. This three-layer arrangement comprehensively improves stress distribution and shrinkage control. Attached Figure Description

[0011] Figure 1 This is a sectional front view of the present invention; Figure 2 This is a schematic diagram of the connection between the expansion ring and the reinforcing cage of this utility model; Figure 3 This is a schematic diagram of the connecting half-ring of this utility model; Figure 4 This is a top view of the two connecting half-rings of this utility model connected by a connecting plate.

[0012] The attached diagram is labeled as follows: 1. Beam and slab, 2. Pipe pile, 3. Reinforcing cage, 3a. First core bar, 3b. Second core bar, 3c. Surrounding bar, 4. Outer steel pipe, 5. Expansion ring, 5a. Connecting half ring, 6. Through hole, 7. Connecting plate one, 8. Connecting plate two, 9. Bolt one, 10. Bolt two, 11. Nut one, 12. Slot. Detailed Implementation

[0013] The present invention will be further described below with reference to the accompanying drawings and specific embodiments: like Figures 1-4 As shown, a prefabricated beam-slab and pipe pile connection structure includes a pipe pile 2 and an outer steel pipe 4 fixedly fitted over the pipe pile 2. A reinforcing cage 3 is provided inside both the outer steel pipe 4 and the pipe pile 2. The reinforcing cage 3 is a structure composed of a first core bar 3a, a second core bar 3b, and surrounding bars 3c. Multiple surrounding bars 3c are spaced apart from top to bottom. The upper end of the reinforcing cage 3 is connected to the beam slab 1 on the upper side of the outer steel pipe 4. It also includes expansion rings 5. The outer steel pipe 4 between the pipe pile 2 and the beam slab 1 is a receiving cavity. Expansion rings 5 ​​are provided in the upper, middle, and lower parts of the receiving cavity. Each expansion ring 5 is fitted and fixed onto the surrounding bars 3c on the outside of the reinforcing cage 3. The expansion ring 5 is a circular ring, and its thickness gradually increases from the outer ring to the inner ring. There is a gap between the outer ring surface of the expansion ring 5 and the inner wall of the outer steel pipe 4. Through holes 6, which are rectangular holes, are arranged in a circular array on the expansion ring 5, penetrating both the upper and lower parts of the expansion ring 5.

[0014] The expansion ring 5 is a circular ring made of micro-expansion concrete, and the expansion ring 5 is detachably connected by front and rear symmetrical connecting half rings 5a.

[0015] The top two ends of the connecting half-ring 5a are connected to connecting plate 7, and the bottom two ends are connected to connecting plate 8. The connecting plate 7 and connecting plate 8 are the same in shape and size. Connecting plate 7 is a right-angled triangular plate. The inclined surface of connecting plate 7 is connected to the top surface of the connecting half-ring 5a. Connecting plate 7 and connecting plate 8 are prefabricated plates made of micro-expansion cement and are integrally formed with the connecting half-ring 5a. The ends of the two connecting half-rings 5a are in contact. The connecting plates 7 on the same side of the top surface of the two connecting half-rings 5a are in contact. The connecting plates 7 on the same side are penetrated by bolt 9. The end of bolt 9 is limited by nut 11. The connecting plates 8 on the same side of the bottom surface of the two connecting half-rings 5a are in contact. The connecting plates 8 on the same side are penetrated by bolt 10. The end of bolt 9 is limited by nut 2.

[0016] The connecting plates 7 and 8 on the same side of each connecting half-ring 5a are symmetrical. One straight surface of the connecting plate 7 is flush with the outer ring of the connecting half-ring 5a, and the other straight surface is flush with the upper end of the connecting half-ring 5a.

[0017] Each of the connecting half-rings 5a has an arc-shaped groove 12 recessed on its inner ring surface. The two ends of the groove 12 pass through the two ends of the connecting half-ring 5a respectively. The ends of the grooves 12 on the two connecting half-rings 5a on the expansion ring 5 contact each other, forming a circular groove that is snapped onto the outside of the corresponding reinforcing bar 3c of the expansion ring 5. The two connecting half-rings 5a can be easily installed outside the corresponding reinforcing bar 3c to form the expansion ring 5. The circular groove inside the expansion ring 5 can improve the connection strength with the reinforcing bar 3c and prevent it from falling off the reinforcing bar 3c.

[0018] The distance between the outer ring of the expansion ring 5 and the outer steel pipe 4 is 5-15mm, and the inner diameter of the expansion ring 5 matches the inner diameter of the surrounding reinforcement 3c.

[0019] During use, as the filling concrete is injected into the outer steel pipe 4 and the pipe pile 2, the reinforcing cage 3 is uniformly wrapped by the filling concrete. After the flowing filling concrete is injected, the precast, dry expansion ring 5 begins to absorb moisture. In the subsequent process, the expansion agent in the expansion ring 5 undergoes a chemical reaction, generating expansion stress. Since the expansion ring 5 is constrained by the outer filling concrete and the rigid outer steel pipe 4, this expansion stress is transformed into outward compression of the inner wall of the outer steel pipe and inward compression of the reinforcing cage 3 and the filling concrete inside the reinforcing cage 3, generating pre-compression stress in the filling concrete area around the expansion ring 5. The expansion effect of the expansion ring 5 actively counteracts the shrinkage trend of the filling concrete, reduces the shrinkage gap between the filling concrete and the inner wall of the outer steel pipe 4, and creates a self-prestressing effect between the filling concrete, the inner wall of the outer steel pipe 4, and the reinforcing cage 3. To ensure that the core-filling concrete can flow through the through holes 6 on the expansion ring 5 during the injection process, preventing the gas inside the outer steel pipe 4 from being unable to escape, and after the core-filling concrete is injected, each through hole 6 is filled with core-filling concrete. After the core-filling concrete solidifies, it fills the through holes 6, forming an effective "pin" anchor, which enhances the bond strength and shear resistance between the expansion ring 5 and the core-filling concrete. Expansion rings 5 ​​are installed at the upper, middle and lower positions of the cavity to more comprehensively control the shrinkage of the filling concrete and improve stress distribution.

[0020] The preferred embodiments of the present utility model have been described in detail above with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Any equivalent or equivalent modifications or substitutions to the technical solutions of the present utility model without departing from the spirit of the present utility model or the scope of disclosure shall fall within the protection scope of the present utility model.

Claims

1. A prefabricated beam-slab and pipe pile connection structure, comprising a pipe pile (2) and a fixed outer steel pipe (4) surrounding the pipe pile (2), wherein a reinforcing cage (3) is provided inside both the outer steel pipe (4) and the pipe pile (2), and the upper end of the reinforcing cage (3) is connected to the beam-slab (1) on the upper side of the outer steel pipe (4); characterized in that, It also includes expansion rings (5). The outer steel pipe (4) between the pipe pile (2) and the beam (1) is a receiving cavity. Expansion rings (5) are provided in the upper, middle and lower parts of the receiving cavity. Each expansion ring (5) is fitted and fixed on the reinforcing bar (3c) on the outside of the reinforcing cage (3). The thickness of the expansion ring (5) gradually increases from the outer ring to the inner ring. There is a gap between the outer ring surface of the expansion ring (5) and the inner wall of the outer steel pipe (4). The expansion ring (5) has a ring array of through holes (6) that penetrate the upper and lower parts of the expansion ring (5).

2. The prefabricated beam-slab and pipe pile connection structure according to claim 1, characterized in that, The expansion ring (5) is a circular ring made of micro-expansion concrete, and the expansion ring (5) is detachably connected by front and rear symmetrical connecting half rings (5a).

3. The prefabricated beam-slab and pipe pile connection structure according to claim 2, characterized in that, The top two ends of the connecting half-ring (5a) are connected to connecting plate one (7), and the bottom two ends are connected to connecting plate two (8). Connecting plate one (7) is a right-angled triangular plate. The inclined surface of connecting plate one (7) is connected to the top surface of the connecting half-ring (5a). The ends of the two connecting half-rings (5a) are in contact with each other. The connecting plates one (7) on the same side of the top surface of the two connecting half-rings (5a) are in contact with each other. The connecting plates one (7) on the same side are penetrated by bolt one (9). The end of bolt one (9) is limited by nut one (11). The connecting plates two (8) on the same side of the bottom surface of the two connecting half-rings (5a) are in contact with each other. The connecting plates two (8) on the same side are penetrated by bolt two (10). The end of bolt one (9) is limited by nut two.

4. The prefabricated beam-slab and pipe pile connection structure according to claim 3, characterized in that, The connecting plates 1 (7) and 2 (8) on the same side of each connecting half ring (5a) are symmetrical. One straight surface of the connecting plate 1 (7) is flush with the outer ring of the connecting half ring (5a), and the other straight surface is flush with the upper end of the connecting half ring (5a).

5. The prefabricated beam-slab and pipe pile connection structure according to claim 3, characterized in that, Each of the connecting half-rings (5a) has an arc-shaped groove (12) recessed on its inner ring surface. The ends of the grooves (12) on the two connecting half-rings (5a) of the expansion ring (5) contact each other, forming a circular groove that is snapped onto the outer side of the corresponding reinforcing bar (3c) of the expansion ring (5).

6. The prefabricated beam-slab and pipe pile connection structure according to claim 5, characterized in that, The distance between the outer ring of the expansion ring (5) and the outer steel pipe (4) is 5-15mm, and the inner diameter of the expansion ring (5) matches the inner diameter of the reinforcing bar (3c).

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