Prefabricated ECC ring-ECC rod-RAC unreinforced beam with recoverable functional connection components

Abstract

This invention relates to a precast ECC ring-ECC rod-RAC unreinforced beam with a recoverable connection component, belonging to the field of structural seismic technology. It includes a precast ECC ring-ECC rod-RAC combined unreinforced beam and a recoverable connection component. The precast ECC ring-ECC rod-RAC combined unreinforced beam is connected to columns via the recoverable connection component. The precast ECC ring-ECC rod-RAC combined unreinforced beam uses recycled concrete (RAC) as the beam structure, with ECC rods and ECC rings replacing the longitudinal reinforcement and stirrups of traditional steel bars, respectively. The recoverable connection component includes UHPC spacers on both sides and an ECC thin shell in the middle. The ECC thin shell consists of two curved thin shells arranged vertically, with multiple sets of X-shaped intersecting resettable CFRP bars between the two ECC thin shells. It has advantages such as being economical and environmentally friendly, lightweight, having excellent seismic performance, and being able to quickly recover its function after an earthquake.

Description

Technical Field

[0001] This invention relates to a prefabricated ECC ring-ECC rod-RAC unreinforced beam with a recoverable connection component, belonging to the field of structural seismic technology. Background Technology

[0002] To meet the ever-increasing demand for urban carrying capacity, a series of renovation and expansion projects have emerged in recent years, generating a large amount of construction solid waste, such as waste concrete debris and brick and stone rubble. The dumping of this construction waste not only wastes land resources but also causes serious pollution to the ecological environment. Furthermore, the storage and transportation of construction solid waste also results in significant secondary energy consumption, which is inconsistent with national low-carbon development requirements. Therefore, utilizing construction solid waste to prepare recycled aggregate concrete (RAC) is an important way to solve the problem of construction solid waste. The widespread application of RAC components can not only effectively solve the problem of reusing construction waste but also significantly reduce carbon emissions during urban renewal, promoting the sustainable development of the construction industry. However, due to the large number of micropores at the interface between new and old cement mortar in RAC components, RAC components generally suffer from low strength, high water absorption, large shrinkage deformation, low elastic modulus, poor durability, and large dispersion in mechanical properties, which seriously restricts the large-scale promotion and application of RAC components.

[0003] Engineered cementitious composites (ECC) are fiber-reinforced cementitious composites with high ductility and toughness. When the fiber content is controlled at 2%, the ultimate compressive strain of ECC is approximately 3 to 5 times that of ordinary concrete, and the ultimate tensile strain is approximately 40 to 60 times that of ordinary concrete. ECC's excellent mechanical properties make it particularly suitable for structural components requiring high energy dissipation, large deformation, and strong shear forces, effectively improving the seismic performance of the structure. Furthermore, ECC's excellent tensile strength and ductile energy dissipation capacity allow it to partially replace the function of stirrups and longitudinal reinforcement. However, ECC also suffers from problems such as low elastic modulus, difficult on-site construction, uncontrollable on-site mechanical properties, and high cost, which restrict its widespread adoption and application.

[0004] Prefabricated construction technology is one of the important measures to achieve industrialization, standardization, and greening of the building industry. In recent years, prefabricated building structures, prefabricated bridge structures, and prefabricated underground structures have emerged continuously. However, the seismic performance of prefabricated components or structures is a key factor limiting their widespread application in complex and harsh environments. In view of this, prefabricated technology can be used to solve the problems of high on-site construction difficulty and on-site quality control of ECC and RAC; it can effectively utilize the mechanical properties of ECC and RAC materials to form ECC-RAC composite components, avoiding the shortcomings of ECC and RAC while giving full play to their advantages; and it can also be used to achieve the post-earthquake recoverability (repairability) function of ECC-RAC composite components, thereby improving the ductility and seismic performance of prefabricated structures. Summary of the Invention

[0005] To address the aforementioned shortcomings of existing technologies, and in order to promote the resource utilization of construction waste, reduce engineering costs and carbon emissions, and achieve post-earthquake recovery and replacement of partial components, this invention proposes a prefabricated ECC ring-ECC bar-RAC unreinforced beam with a recoverable connection assembly. It uses prefabricated ECC rings instead of stirrups and prefabricated ECC bars instead of longitudinal reinforcement, offering advantages such as economic and environmental friendliness, lightweight structure, excellent seismic performance, and rapid post-earthquake recovery. It can be used in prefabricated beam-column frame beams, bridge pier tie beams, and other applications.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A precast ECC ring-ECC rod-RAC unreinforced beam with a recoverable connection component includes a precast ECC ring-ECC rod-RAC combined unreinforced beam and a recoverable connection component. The precast ECC ring-ECC rod-RAC combined unreinforced beam is connected to a column via the recoverable connection component. The precast ECC ring-ECC rod-RAC combined unreinforced beam uses recycled concrete RAC as the beam structure, and ECC rods and ECC rings are installed inside the beam to replace the longitudinal reinforcement and stirrups of traditional steel bars, respectively. Pre-reserved tie beam channels are reserved on the outer sides of both ends of the precast ECC ring-ECC rod-RAC combined unreinforced beam. The recoverable connection component includes UHPC pads on both sides. The system includes an ECC thin shell in the middle, consisting of two curved thin shells arranged on the top and bottom, with multiple sets of X-shaped intersecting reset CFRP reinforcement bars between the two shells; the UHPC pad has reserved channels and prestressed channels, and the precast ECC thin shell has reserved channels on both sides; the UHPC pad and the precast ECC thin shell are connected together by anchor bolts passing through the reserved channels and shell reserved channels, and the anchor bolts are also connected to the precast ECC ring-ECC rod-RAC combined unreinforced beam and column through the reserved channels of the tie beam and column respectively; the reset CFRP reinforcement bars are inserted into the UHPC pads on both sides and anchored in the prestressed channels.

[0008] Furthermore, the column is a bridge pier column or a frame column.

[0009] Furthermore, the outer surface of the prefabricated ECC shell with pre-reserved holes is flush with the outer surface of the UHPC pad.

[0010] Furthermore, the X-shaped intersecting reset CFRP ribs are arranged in 3-8 groups, with each group having 2 X-shaped intersecting reset CFRP ribs.

[0011] Furthermore, the prefabricated ECC ring-ECC rod-RAC combined unreinforced beam, UHPC pad, and prefabricated ECC thin shell are all prefabricated structures that can be replaced or repaired after an earthquake.

[0012] Furthermore, the number and spacing of ECC bars and ECC rings can be adjusted according to the shear and bending bearing capacity requirements; according to the different tensile bearing capacity requirements of beam members, the structure of ECC ring-ECC bar-RAC composite unreinforced beam can be divided into two types: RAC composite unreinforced beam containing prefabricated ECC rings and ECC bars, and RAC composite unreinforced beam containing prefabricated ECC tubes, ECC rings, and ECC bars.

[0013] Furthermore, the prefabricated ECC tube, ECC ring, and ECC rod are made of pure ECC material, or the ECC tube, ECC ring, and ECC rod are made of FRP or GFRP to constrain the ECC.

[0014] Furthermore, the number and strength of the reset CFRP ribs are determined according to the reset performance requirements.

[0015] A method for constructing bridge pier tie beams, which employs the aforementioned prefabricated ECC ring-ECC rod-RAC unreinforced beam with reversible connection components. The ECC ring-ECC rod-RAC combined unreinforced beam is a RAC combined unreinforced beam containing prefabricated ECC pipes, ECC rings, and ECC rods. The construction method is as follows:

[0016] Step 1: During the fabrication process, first pour the ECC pipe, ECC ring, and ECC rod. After curing, use wire to assemble them into an ECC rod-ECC ring skeleton and place it inside the ECC pipe.

[0017] Step 2: Based on this, reserve holes for the tie beam at both ends of the tie beam mold, and pour RAC concrete into the ECC pipe containing the ECC rod-ECC ring skeleton to form a precast ECC ring-ECC rod-RAC composite unreinforced tie beam.

[0018] Step 3: Prepare UHPC pads. It is necessary to reserve pre-drilled holes and prestressed holes. One side of the pre-drilled hole is used to connect the ECC thin shell, and the other side of the pre-drilled hole is used to connect the UHPC pads to the piers or tie beams. The prestressed holes are used to thread the CFRP reinforcement when two adjacent UHPC pads are connected.

[0019] Step 4: ECC thin shell fabrication. During the casting of the ECC thin shell, pre-reserved channels are also set in the shell. During assembly, anchor bolts or shear nails are passed through the pre-reserved channels and the UHPC pads are connected to the ECC thin shell.

[0020] Step 5: After the prefabricated ECC ring-ECC bar-RAC combined unreinforced tie beam, UHPC pad, and ECC thin shell are processed in the factory, they are transported to the site. During construction, the reversible functional connection components are assembled first. After connecting the UHPC pad and ECC thin shell with anchor bolts or shear nails, the reset CFRP bar is passed through the anchoring section of the UHPC pad in sequence and comes out from the tensioning end of another UHPC pad for tensioning. After fixing the reset CFRP bar, non-shrink cement grout is injected into the prestressed duct where the reset CFRP bar is located.

[0021] Step Six: Fix the combined structure formed by the above-mentioned recoverable functional connection components to the corresponding column connection hole position on the inside of the pier column using shear nails or anchor bolts. Then connect the prefabricated ECC ring-ECC bar-RAC unreinforced tie beam to the other side of the recoverable functional connection components using anchor bolts or shear nails. At this point, the double column pier assembly is completed.

[0022] A method for constructing frame beams, which employs the aforementioned prefabricated ECC ring-ECC bar-RAC unreinforced beam with reversible connection components. The ECC ring-ECC bar-RAC combined unreinforced beam is a RAC combined unreinforced beam containing prefabricated ECC rings and ECC bars. The construction method is as follows:

[0023] Step 1: During fabrication, first cast the ECC ring and ECC rod, and after curing, use wire to assemble them into an ECC rod-ECC ring skeleton, and then place it inside the ECC tube;

[0024] Step 2: Based on this, reserve holes for the tie beam at both ends of the tie beam mold, and pour RAC concrete into the mold containing the ECC rod-ECC ring skeleton to form a precast ECC ring-ECC rod-RAC composite unreinforced tie beam.

[0025] Step 3: Prepare UHPC pads. It is necessary to reserve pre-drilled holes and prestressed holes. One side of the pre-drilled hole is used to connect the ECC thin shell, and the other side of the pre-drilled hole is used to connect the UHPC pads to the piers or tie beams. The prestressed holes are used to thread the CFRP reinforcement when two adjacent UHPC pads are connected.

[0026] Step 4: ECC thin shell fabrication. During the casting of the ECC thin shell, pre-reserved channels are also set in the shell. During assembly, anchor bolts or shear nails are passed through the pre-reserved channels and the UHPC pads are connected to the ECC thin shell.

[0027] Step 5: The precast ECC ring-ECC bar-RAC combined unreinforced tie beam and UHPC pads are processed in the ECC thin shell factory and transported to the site. During construction, one UHPC pad is fixed to the inside of the frame column in advance using anchor bolts or shear nails, and the other UHPC pad is fixed to both sides of the precast ECC ring-ECC bar-RAC combined unreinforced tie beam.

[0028] Step Six: At the construction site, hoist the precast ECC ring-ECC rod-RAC combined unreinforced tie beam with the UHPC pads fixed to it between the two frame columns. Fix the ECC thin shell between the frame column and the precast ECC ring-ECC rod-RAC combined unreinforced tie beam with anchor bolts or shear nails. Then, pass the prestressed CFRP reinforcement through the prestressed duct to form an X shape, and inject non-shrink cement grout into the prestressed duct where the reset CFRP reinforcement is located. At this point, the beam-column frame construction is completed.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The precast ECC ring-ECC bar-RAC unreinforced beam of this invention has advantages such as light weight, low cost, environmental friendliness, and factory prefabrication. By using ECC bars instead of longitudinal reinforcement and ECC rings instead of stirrups, the advantages of ECC materials, such as tensile hardening and high ductility, can be fully utilized, while achieving a lightweight, unreinforced beam that is economical. Furthermore, although the unreinforced ECC-RAC composite beam has a lower overall load-bearing capacity, it has a higher energy dissipation capacity. It allows for controllable seismic damage or plastic hinge positions without reducing the resistance of the frame structure and piers, thus realizing the design concept of strong column-weak beam and controllable plastic hinges.

[0031] 2. The prefabricated ECC ring-ECC rod-RAC unreinforced beam and its recoverable functional connection components in this invention, including UHPC blocks, ECC shells, ECC rods, ECC rings, RAC beams, and ECC pipes, can all be produced in a standardized manner in the factory. They are easy to manufacture and assemble, and can be directly replaced after earthquake damage. This solves the problems of severe pier damage and difficult repair in ordinary double-column pier systems after earthquakes.

[0032] 3. The recoverable functional connection component in this invention consists of an ECC thin shell, a UHPC block, and a reset CFRP rib. The ECC thin shell mainly bears tensile loads, the UHPC block mainly bears compressive loads, and the reset CFRP rib mainly performs the reset function. The combination of the three components can give full play to the advantages of their respective material mechanical properties.

[0033] 4. The prefabricated ECC ring-ECC bar-RAC unreinforced beam and its recoverable functional connection components in this invention can be applied not only to bridge pier tie beams, but also to beam-containing systems such as frame beams and shear wall tie beams. Furthermore, due to the assemblable nature of this system, the strength and quantity of each component can be modified according to specific circumstances to achieve both structural bearing capacity and economic and environmental requirements. Attached Figure Description

[0034] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0035] Figure 2 This is a three-dimensional schematic diagram of the recoverable connection component in this invention;

[0036] Figure 3 This is a cross-sectional view of the recoverable connection component in this invention;

[0037] Figure 4 This is a composite unreinforced beam of ECC ring-ECC bar-RAC according to the present invention and its axonometric view;

[0038] Figure 5 This is a schematic diagram of the UHPC pad in the present invention;

[0039] Figure 6 This is a schematic diagram of the ECC thin shell in this invention;

[0040] Figure 7 This is a schematic diagram of the repositioning CFRP rib connection in this invention;

[0041] Figure 8 This is a schematic diagram of the completed beam-column frame construction in this invention;

[0042] Figure 9 This is an axonometric view of another ECC ring-ECC bar-RAC combined unreinforced beam according to the present invention. Detailed Implementation

[0043] The following is in conjunction with the appendix Figure 1-9 The present invention will be further described in detail below to facilitate a clear understanding of the invention, but these descriptions do not constitute a limitation thereof.

[0044] Example 1

[0045] As attached Figure 1-7 As shown in this embodiment, a precast ECC ring-ECC bar-RAC unreinforced beam with a recoverable connection component is applied in the construction of bridge pier tie beams. It includes a precast ECC ring-ECC bar-RAC combined unreinforced beam 1 and a recoverable connection component. The precast ECC ring-ECC bar-RAC combined unreinforced beam 1 is connected to the columns via the recoverable connection component. The precast ECC ring-ECC bar-RAC combined unreinforced beam 1 uses recycled concrete RAC as the beam structure, and ECC bars 1a and ECC rings 1b are provided inside the beam to replace the longitudinal reinforcement and stirrups of traditional steel bars, respectively. Tie beam pre-reserved ducts 1c are reserved on the outer sides of both ends of the precast ECC ring-ECC bar-RAC combined unreinforced beam 1. The recoverable connection component includes UHPC pads on both sides. Block 2 and the ECC thin shell 3 set in the middle, the ECC thin shell 3 is two curved thin shells set on the top and bottom, and multiple sets of X-shaped intersecting reset CFRP ribs 4 are arranged between the two ECC thin shells 3; the UHPC pad block 2 is provided with reserved channels 2a and prestressed channels 2b, and the precast ECC thin shell 3 has reserved shell reserved channels 3a on both sides; the UHPC pad block 2 and the precast ECC thin shell 3 are connected together by anchor bolts 5 passing through the reserved channels 2a and shell reserved channels 3a, and the anchor bolts 5 are also connected to the precast ECC ring-ECC rod-RAC combined unreinforced beam 1 and the column through the reserved channel 1c of the tie beam and the column connection channel respectively; the reset CFRP ribs 4 are inserted into the UHPC pad blocks 2 on both sides and anchored in the prestressed channels 2b.

[0046] In this embodiment, the column is a bridge pier, and the outer surface of the prefabricated ECC thin shell 3 with pre-reserved openings 3a is flush with the outer surface of the UHPC pad 2. For example, Figure 7As shown, there are 3 groups of X-shaped intersecting reset CFRP ribs 4, with 2 X-shaped intersecting reset CFRP ribs 4 in each group. The precast ECC ring-ECC rod-RAC composite unreinforced beam 1, UHPC pad block 2, and precast ECC thin shell 3 are all precast structures that can be replaced or repaired after an earthquake.

[0047] like Figure 4 As shown, in this embodiment, the ECC ring-ECC rod-RAC composite unreinforced beam 1 is a RAC composite unreinforced beam containing prefabricated ECC tubes, ECC rings 1b, and ECC rods 1a. The number and spacing of ECC rods 1a and ECC rings 1b can be adjusted according to the shear and bending bearing capacity requirements. The ECC tubes, ECC rings 1b, and ECC rods 1a are made of pure ECC material. Furthermore, the number and strength of the reset CFRP reinforcement 4 are determined according to the reset performance requirements.

[0048] A method for constructing bridge pier tie beams, the method is as follows:

[0049] Step 1: During the fabrication process, first pour the ECC pipe, ECC ring 1b, and ECC rod 1a. After curing, use wire to assemble them into an ECC rod-ECC ring skeleton and place it inside the ECC pipe.

[0050] Step 2: Based on this, reserve holes 1c for the tie beam at both ends of the tie beam mold, and pour RAC concrete into the ECC pipe containing the ECC rod-ECC ring skeleton to form a precast ECC ring-ECC rod-RAC composite unreinforced tie beam 1.

[0051] Step 3: Prepare UHPC pad 2. It is necessary to reserve the reserved duct 2a and the prestressed duct 2b. One side of the reserved duct 2a is used to connect the ECC thin shell 3, and the other side of the reserved duct 2a is used to connect the UHPC pad 2 to the pier or tie beam. The prestressed duct 2b is used to pass the reset CFRP reinforcement 4 when two adjacent UHPC pads 2 are connected.

[0052] Step 4: Fabrication of ECC thin shell 3. During the casting of ECC thin shell 3, a shell pre-reserved channel 3a is also set. During assembly, the anchor bolt 5 or shear nail is passed through the shell pre-reserved channel 3a and the pre-reserved channel 2a to connect the UHPC pad 2 to the ECC thin shell 3.

[0053] Step 5: After the prefabricated ECC ring-ECC bar-RAC combined unreinforced tie beam 1, UHPC pad 2, and ECC thin shell 3 are processed in the factory, they are transported to the site. During construction, the reversible functional connection components are assembled first. After connecting UHPC pad 2 and ECC thin shell 3 with anchor bolts 5 or shear nails, the reset CFRP bar 4 is passed through the anchoring section of UHPC pad 2 in sequence and comes out from the tensioning end of another UHPC pad 2 for tensioning. After fixing the reset CFRP bar 4, non-shrink cement grout is injected into the prestressed duct 2b where the reset CFRP bar 4 is located.

[0054] Step 6: Fix the combined structure formed by the above-mentioned recoverable functional connection components to the corresponding column connection hole position on the inside of the pier column using shear nails or anchor bolts 5. Then connect the precast ECC ring-ECC rod-RAC unreinforced tie beam 1 to the other side of the recoverable functional connection components using anchor bolts 5 or shear nails. At this point, the double column pier assembly is completed.

[0055] Example 2

[0056] like Figure 1-3 As shown in Figures 5-9, in this embodiment, a prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection component is used. The column is a frame column, and the ECC ring-ECC rod-RAC combined unreinforced beam 1 is a RAC combined unreinforced beam containing prefabricated ECC ring 1b and ECC rod 1a. The remaining structure is the same as in Embodiment 1. Figure 8 As shown, the construction method for this frame beam is as follows:

[0057] Step 1: During the fabrication process, first cast ECC ring 1b and ECC rod 1a. After curing, use wire to assemble them into an ECC rod-ECC ring skeleton and place it inside the ECC pipe.

[0058] Step 2: Based on this, reserve holes 1c for the tie beam at both ends of the tie beam mold, and pour RAC concrete into the mold containing the ECC rod-ECC ring skeleton to form a precast ECC ring-ECC rod-RAC composite unreinforced tie beam 1.

[0059] Step 3: Prepare UHPC pad 2. It is necessary to reserve the reserved duct 2a and the prestressed duct 2b. One side of the reserved duct 2a is used to connect the ECC thin shell 3, and the other side of the reserved duct 2a is used to connect the UHPC pad 2 to the pier or tie beam. The prestressed duct 2b is used to pass the reset CFRP reinforcement 4 when two adjacent UHPC pads 2 are connected.

[0060] Step 4: Fabrication of ECC thin shell 3. During the casting of ECC thin shell 3, a shell pre-reserved channel 3a is also set. During assembly, the anchor bolt 5 or shear nail is passed through the shell pre-reserved channel 3a and the pre-reserved channel 2a to connect the UHPC pad 2 to the ECC thin shell 3.

[0061] Step 5: After the prefabricated ECC ring-ECC bar-RAC combined unreinforced tie beam 1, UHPC pad 2, and ECC thin shell 3 are processed in the factory, transport them to the site. During construction, fix one UHPC pad 2 to the inside of the frame column in advance using anchor bolts 5 or shear nails, and then fix the other UHPC pad 2 to both sides of the prefabricated ECC ring-ECC bar-RAC combined unreinforced tie beam 1.

[0062] Step Six: At the construction site, hoist the precast ECC ring-ECC rod-RAC combined unreinforced tie beam 1, with the UHPC pad 2 fixed, between the two frame columns. Fix the ECC thin shell 3 between the frame column and the precast ECC ring-ECC rod-RAC combined unreinforced tie beam 1 using anchor bolts 5 or shear nails. Then, pass the prestressed CFRP reinforcement 4 through the prestressed duct 2b to form an X shape, and inject non-shrink cement grout into the prestressed duct 2b where the reset CFRP reinforcement 4 is located. At this point, the beam-column frame construction is completed.

[0063] The above are merely preferred embodiments of the present invention and do not constitute any limitation on the structure of the present invention. The arrangement and quantity of the present invention are not limited to this example and can be optimized according to actual engineering conditions. Any modifications, equivalent changes, and decorations made to the above embodiments based on the technical principles of the present invention, without departing from the scope of the present invention, are still within the scope of the present invention.

Claims

1. A prefabricated ECC ring-ECC bar-RAC unreinforced beam with a reversible connection assembly, characterized in that: The structure includes a precast ECC ring-ECC bar-RAC composite unreinforced beam (1) and a recoverable functional connection component. The precast ECC ring-ECC bar-RAC composite unreinforced beam (1) is connected to the column through the recoverable functional connection component. The precast ECC ring-ECC bar-RAC composite unreinforced beam (1) uses recycled concrete RAC as the beam structure. ECC bars (1a) and ECC rings (1b) are set inside the beam to replace the longitudinal bars and stirrups of traditional steel bars, respectively. The precast ECC ring-ECC bar-RAC composite unreinforced beam (1) has reserved tie beam reserved holes (1c) on the outer sides of both ends. The recoverable functional connection component includes UHPC pads (2) on both sides and an ECC thin shell (3) set in the middle. The ECC thin shell (3) is two curved thin shells set on the top and bottom. The shell consists of two ECC thin shells (3) with multiple sets of X-shaped intersecting reset CFRP ribs (4); the UHPC pad (2) is provided with reserved channels (2a) and prestressed channels (2b), and the precast ECC thin shell (3) has reserved shell reserved channels (3a) on both sides; the UHPC pad (2) and the precast ECC thin shell (3) are connected together by anchor bolts (5) passing through the reserved channels (2a) and the shell reserved channels (3a), and the anchor bolts (5) are also connected to the precast ECC ring-ECC rod-RAC combined unreinforced beam (1) and the column through the reserved channels (1c) of the tie beam and the column connection channel respectively; the reset CFRP ribs (4) are inserted into the UHPC pads (2) on both sides and anchored in the prestressed channels (2b).

2. The prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection component according to claim 1, characterized in that: The columns are bridge piers or frame columns.

3. The prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection component according to claim 1, characterized in that: The outer surface of the shell reserved hole (3a) of the prefabricated ECC shell (3) is flush with the outer surface of the UHPC pad (2).

4. A prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection assembly according to claim 1, characterized in that: The X-shaped cross-set reset CFRP ribs (4) are in groups of 3-8, with each group having 2 X-shaped cross-set reset CFRP ribs (4).

5. A prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection assembly according to claim 1, characterized in that: The precast ECC ring-ECC rod-RAC combined unreinforced beam (1), UHPC pad (2), and precast ECC thin shell (3) are all precast structures that can be replaced or repaired after an earthquake.

6. A prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection assembly according to claim 1, characterized in that: Adjust the number and spacing of ECC bars (1a) and ECC rings (1b) according to the shear and bending bearing capacity requirements; according to the different tensile bearing capacity requirements of the beam members, set the structure of the ECC ring-ECC bar-RAC composite unreinforced beam (1) as a RAC composite unreinforced beam containing prefabricated ECC rings (1b) and ECC bars (1a) or a RAC composite unreinforced beam containing prefabricated ECC pipes, ECC rings (1b) and ECC bars (1a).

7. A prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection assembly according to claim 6, characterized in that: The prefabricated ECC tube, ECC ring (1b), and ECC rod (1a) are made of pure ECC material, or the ECC tube, ECC ring (1b), and ECC rod (1a) are made of FRP or GFRP to constrain the ECC.

8. A prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection assembly according to claim 1, characterized in that: The number and strength of the reset CFRP ribs (4) are determined according to the reset performance requirements.

9. A method for constructing a bridge pier tie beam, comprising a prefabricated ECC ring-ECC rod-RAC unreinforced beam with a reversible connection component as described in claim 6, wherein the ECC ring-ECC rod-RAC combined unreinforced beam (1) is a RAC combined unreinforced beam containing prefabricated ECC pipes, ECC rings (1b), and ECC rods (1a), characterized in that, The construction method is as follows: Step 1: During the fabrication process, first pour the ECC pipe, ECC ring (1b), and ECC rod (1a). After curing, use wire to assemble them into an ECC rod-ECC ring skeleton and place it inside the ECC pipe. Step 2: Based on this, reserve holes (1c) for the tie beam at both ends of the tie beam mold, and pour RAC concrete into the ECC pipe containing the ECC rod-ECC ring skeleton to form a precast ECC ring-ECC rod-RAC composite unreinforced tie beam (1). Step 3: Prepare UHPC pads (2), which requires pre-reserved ducts (2a) and prestressed ducts (2b). One side of the pre-reserved duct (2a) is used to connect the ECC thin shell (3), and the other side of the pre-reserved duct (2a) is used to connect the UHPC pads (2) to the pier or tie beam. The prestressed duct (2b) is used to pass the reset CFRP reinforcement (4) when two adjacent UHPC pads (2) are connected. Step 4: Fabrication of ECC thin shell (3). During the casting of ECC thin shell (3), a shell pre-reserved channel (3a) is also set. During assembly, anchor bolts (5) or shear nails are passed through the shell pre-reserved channel (3a) and the pre-reserved channel (2a) to connect UHPC pad (2) to ECC thin shell (3). Step 5: After the prefabricated ECC ring-ECC rod-RAC combined unreinforced tie beam (1), UHPC pad (2), and ECC thin shell (3) are processed in the factory, they are transported to the site. During construction, the reversible functional connection components are assembled first. After connecting the UHPC pad (2) and ECC thin shell (3) with anchor bolts (5) or shear nails, the reset CFRP bar (4) is passed through the anchoring section of the UHPC pad (2) in sequence and passed out from the tensioning end of another UHPC pad (2) for tensioning. After fixing the reset CFRP bar (4), non-shrink cement grout is injected into the prestressed duct (2b) where the reset CFRP bar (4) is located. Step 6: Fix the combined structure formed by the above-mentioned recoverable functional connection components to the corresponding column connection hole position on the inside of the pier column using shear nails or anchor bolts (5). Then connect the precast ECC ring-ECC rod-RAC unreinforced tie beam (1) to the other side of the recoverable functional connection components using anchor bolts (5) or shear nails. The double column pier assembly is now complete.

10. A method for constructing a frame beam, comprising a prefabricated ECC ring-ECC bar-RAC unreinforced beam with reversible connection components as described in any one of claims 1-8, wherein the ECC ring-ECC bar-RAC combined unreinforced beam (1) is a RAC combined unreinforced beam containing prefabricated ECC rings (1b) and ECC bars (1a), characterized in that, The construction method is as follows: Step 1: During the fabrication process, first cast the ECC ring (1b) and ECC rod (1a). After curing, use wire to assemble them into an ECC rod-ECC ring skeleton and place it in the mold. Step 2: Based on this, reserve holes (1c) for the tie beam at both ends of the tie beam mold, and pour RAC concrete into the mold containing the ECC rod-ECC ring skeleton to form a precast ECC ring-ECC rod-RAC composite unreinforced tie beam (1). Step 3: Prepare UHPC pads (2), which requires pre-reserved ducts (2a) and prestressed ducts (2b). One side of the pre-reserved duct (2a) is used to connect the ECC thin shell (3), and the other side of the pre-reserved duct (2a) is used to connect the UHPC pads (2) to the pier or tie beam. The prestressed duct (2b) is used to pass the reset CFRP reinforcement (4) when two adjacent UHPC pads (2) are connected. Step 4: Fabrication of ECC thin shell (3). During the casting of ECC thin shell (3), a shell pre-reserved channel (3a) is also set. During assembly, anchor bolts (5) or shear nails are passed through the shell pre-reserved channel (3a) and the pre-reserved channel (2a) to connect UHPC pad (2) to ECC thin shell (3). Step 5: After the prefabricated ECC ring-ECC bar-RAC combined unreinforced tie beam (1), UHPC pad (2), and ECC thin shell (3) are processed in the factory, they are transported to the site. During construction, one UHPC pad (2) is fixed to the inside of the frame column in advance using anchor bolts (5) or shear nails, and another UHPC pad (2) is fixed to both sides of the prefabricated ECC ring-ECC bar-RAC combined unreinforced tie beam (1). Step 6: At the construction site, hoist the precast ECC ring-ECC rod-RAC combined unreinforced tie beam (1) with the fixed UHPC pad (2) between the two frame columns. Fix the ECC thin shell (3) between the frame column and the precast ECC ring-ECC rod-RAC combined unreinforced tie beam (1) with anchor bolts (5) or shear nails. Then pass through the reset CFRP reinforcement (4) through the prestressed duct (2b) to form an X shape. Inject non-shrink cement grout into the prestressed duct (2b) where the reset CFRP reinforcement (4) is located. The beam and column frame construction is now complete.

Images