A UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system and its design and construction method.

Abstract

This invention discloses a post-tensioned bonded prestressed concrete perforated beam frame structure system with UHPC (Ultra-High-Pressure Polymer) connection, comprising a precast concrete upper column, a precast concrete lower column, a post-tensioned bonded precast prestressed concrete perforated composite beam, a UHPC node core area, and a composite slab. The upper longitudinal main reinforcement extends from the bottom surface of the precast upper column and is directly anchored within the UHPC node core area; the lower longitudinal main reinforcement extends from the top surface of the precast lower column and is directly anchored within the UHPC node core area; and ordinary steel reinforcement extends from the end face of the precast concrete beam and is directly anchored within the UHPC node core area. This structural system not only facilitates and speeds on-site construction and improves component installation efficiency, but also significantly reduces the anchorage length of the reinforcement, greatly reduces the amount of stirrups in the node core area, avoids reinforcement congestion in the node core area, reduces the component cross-sectional height, lightens the self-weight, and improves the crack resistance and load-bearing capacity of the components, thereby improving the seismic performance of the overall frame structure.

Description

Technical Field

[0001] This invention relates to the field of precast prestressed prefabricated building construction technology, and more specifically, to a UHPC-connected post-tensioned bonded precast prestressed concrete perforated beam frame structure system and its design and construction method. Background Technology

[0002] Cast-in-place structures suffer from numerous limitations, including low construction efficiency and high energy consumption, making them increasingly unsuitable for the demands of industrialized building development. Precast concrete structures, with their advantages of rapid construction, factory-produced components, reduced on-site wet work, and reduced environmental pollution, have become the future direction of industrialized building development. After years of development and promotion, precast concrete structures have been widely researched and used.

[0003] Precast concrete frame structures refer to structures where beams and columns are prefabricated in a prefabrication plant and transported to the construction site for connection to form an integral structure. Compared with cast-in-place concrete structures, they offer advantages such as faster construction speed, easier assurance of component quality, higher overall quality, less environmental pollution, reduced labor costs, and savings in formwork and supports, making them a structural form with a very broad prospect. For wet-connection precast concrete frame structures, easy-to-construct and effectively guaranteed joint construction methods are key to their widespread application. However, based on past earthquake disasters, precast structures have suffered more severe damage in earthquakes, making it difficult to achieve the same seismic performance as cast-in-place structures. To improve the integrity and reliability of joint connections in precast concrete frames and achieve or even surpass the seismic performance of cast-in-place concrete structures, prestressed technology and UHPC (Ultra High Performance Concrete) materials have been introduced into precast structures.

[0004] Post-tensioned bonded prestressed precast concrete structures are structures formed by assembling precast components together through tensioning prestressing tendons and grouting. They combine the characteristics of both post-tensioned bonded prestressed concrete structures and precast structures. The internal stress generated by prestressing in the concrete section can partially or completely offset the stress on the section under service loads, delaying crack initiation and improving the stiffness of the components. Upon unloading, cracks can partially or completely close, demonstrating good elastic recovery performance. Simultaneously, prestressed concrete can fully utilize the material strength of both prestressing tendons and concrete, reducing the structure's self-weight. Furthermore, the application of prestressing contributes to improved performance and overall integrity of precast structures, promoting their application in large-span, heavy-load structures.

[0005] UHPC possesses excellent bonding properties, significantly reducing the anchorage length of reinforcing bars and strands. Its high strength reduces the amount of stirrups required in the joint core area. Using UHPC in the joint core area simplifies the construction and improves the overall frame integrity. Prestressed structures exhibit excellent load-bearing performance; applying UHPC to the joint core area creates a precast prestressed frame structure. In-depth research on this structure will facilitate the further promotion and application of precast prestressed concrete frame structures. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies and, by leveraging the superior performance of UHPC (Ultra-High-Pressure Concrete), propose a UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system, along with its design and construction methods. This system combines three traditional structural elements: post-tensioned bonded prestressed structures, prefabricated structures, and composite structures, and utilizes high-performance UHPC materials to improve the seismic performance of prefabricated prefabricated concrete frame structures.

[0007] The advantages of this invention are mainly reflected in two aspects: the connection technology of precast concrete beam-column components and the reinforcement connection technology between components. Regarding component connection technology, beam-column components are connected through high-performance UHPC (Ultra-High-Pressure Polymer) to form a UHPC node core area, making it easier to meet the seismic fortification requirements of strong nodes and weak components, thereby improving the ductility of beam-column nodes and ultimately improving the seismic performance of the overall frame structure. Regarding reinforcement connection technology, the reinforcement between beam-column components only requires simple lap splices with very short lap lengths, significantly saving the fabrication time and on-site installation time of precast components. Therefore, the UHPC-connected post-tensioned bonded precast prestressed concrete perforated beam frame structure system and its design and construction methods proposed in this invention are in line with my country's green development strategy for building industrialization.

[0008] The technical problem solved by this invention can be achieved by the following technical solutions:

[0009] A UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system includes a precast concrete upper column, a precast concrete lower column, a post-tensioned bonded prestressed concrete perforated composite beam, a UHPC node core area, and a composite slab.

[0010] The precast concrete upper column is provided with upper longitudinal main reinforcement, and the precast concrete lower column is provided with lower longitudinal main reinforcement. The post-tensioned bonded precast prestressed concrete perforated composite beam is provided with a precast concrete perforated beam, a beam composite layer and post-tensioned bonded prestressed tendons. The bottom of the precast concrete perforated beam is provided with ordinary steel bars. If necessary, hanging bars or steel mesh can also be provided at the opening. The steel mesh can also be welded steel mesh. The beam composite layer is provided with top continuous steel bars. The composite slab is composed of a precast concrete slab and a slab composite layer cast on the slab.

[0011] The upper longitudinal main reinforcement extends out of the bottom surface of the precast upper column and is directly anchored in the core area of ​​the UHPC node; the lower longitudinal main reinforcement extends out of the top surface of the precast lower column and is directly anchored in the core area of ​​the UHPC node; and the ordinary steel reinforcement extends out of the end face of the precast concrete perforated beam and is directly anchored in the core area of ​​the UHPC node.

[0012] The post-tensioned bonded prestressed concrete perforated composite beam also includes a fully prestressed prestressed concrete perforated beam; the bonded prestressing tendons include straight, broken, and curved prestressing tendons.

[0013] The bonded prestressed tendons in the core area of ​​the node can be bonded, bonded, partially bonded and unbonded, or unbonded.

[0014] Before pouring the beam-slab composite layer, slab composite layer, and UHPC node core area, the post-tensioned precast prestressed concrete perforated composite beam is constructed and verified using a force transmission mode adapted to ordinary concrete perforated simply supported beams and bracing. After pouring the node core area, beam-slab composite layer, and slab composite layer, once the concrete strength of the node and composite layer reaches the design requirements, the bonded prestressing tendons are tensioned. After tensioning, the bracing is removed, and construction stage verification is performed as an unbonded frame beam. The upper chord section at the opening of the post-tensioned precast prestressed concrete perforated composite beam differs before and after pouring the beam-slab composite layer, slab composite layer, and UHPC node core area, resulting in different stress states. Therefore, construction verification should be performed on the upper and lower chords at the opening of the precast concrete perforated beam. For the bonded and unbonded / unbonded portions of the node core area, calculations are performed based on effective prestress under normal serviceability limit state. Under ultimate bearing limit state, the stress increment of the unbonded tendons is considered. Under seismic loads, the recovery performance provided by the unbonded tendons is considered.

[0015] Furthermore, the post-tensioned bonded precast prestressed concrete perforated composite beam consists of a precast concrete perforated beam, a beam composite layer, and post-tensioned bonded prestressing tendons.

[0016] Furthermore, the post-tensioned bonded prestressing tendons are installed inside the corrugated pipes embedded in the precast concrete perforated beam members, and pass through the corrugated pipes embedded in the beam composite layer and the core area of ​​the UHPC node, with both ends extending outside the core area of ​​the UHPC node. Clamps and anchors are respectively fixed at both ends.

[0017] Furthermore, recessed grooves are provided on the bottom surface of the precast concrete upper column, the top surface of the precast concrete lower column, and the end face of the post-tensioned bonded precast prestressed concrete perforated composite beam.

[0018] Furthermore, the precast concrete upper column is fixed in the corresponding position using reliable supports.

[0019] Furthermore, the stirrups in the precast concrete upper column, precast concrete lower column, and post-tensioned bonded precast prestressed concrete perforated composite beam are divided into a dense zone and a non-dense zone. The stirrups in the core area of ​​the UHPC node are arranged according to design requirements. The shear bearing capacity of the core area is calculated according to the diagonal compression member and truss model, and the steel fibers in the UHPC are considered to be equivalent to horizontal stirrups and vertical longitudinal bars, and their contribution to the shear resistance of the core area of ​​the node is considered. At the same time, the beneficial contribution of bonded prestressed tendons to the shear resistance of the node is also considered.

[0020] Furthermore, the top surface of the precast concrete perforated beam and the precast concrete slab is provided with a rough surface layer.

[0021] This invention also provides a design method for the system, comprising the following steps:

[0022] Step 1: Design beams and columns according to existing specifications and invention patents;

[0023] Step 2: Verify the strength of the upper and lower chords at the opening of the precast concrete perforated beam before casting the beam composite layer, slab composite layer and UHPC node core area of ​​the precast prestressed concrete perforated composite beam.

[0024] Step 3: The opening position in the precast prestressed concrete perforated composite beam should be located in the middle 1 / 3 section as much as possible. When it is located in the end 1 / 3 section of the beam, the distance from the edge of the hole near the node to the inner edge of the node should be greater than 1.5 times the beam height.

[0025] A UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system includes the following steps:

[0026] Step 1: Construct precast concrete lower columns, precast concrete upper columns, precast concrete perforated beams, and precast concrete slabs; among them, sufficient anchorage length must be reserved for the longitudinal reinforcement extending from the precast concrete lower columns and precast concrete upper columns and anchoring them into the core area of ​​the node; sufficient anchorage length must be reserved for the ordinary steel bars extending from the precast concrete perforated beams and anchoring them into the core area of ​​the node; corrugated pipes are pre-embedded in the precast concrete perforated beams according to the design position of the prestressing tendons;

[0027] Step 2: After the precast components are made, hoist the precast concrete lower column and install it on the foundation, and then install an appropriate number of stirrups on the extended longitudinal main bars;

[0028] Step 3: Hoist the precast concrete beam to the top surface of the precast concrete lower column, so that the bottom surface of the precast concrete perforated beam is flush with the top surface of the precast concrete lower column, and place the end of the precast concrete perforated beam on the precast concrete lower column and fix it with supports; wherein, the reinforcing bars extending from the precast concrete perforated beams on both sides are reasonably avoided in the core area of ​​the node and directly anchored.

[0029] Step 4: Hoist the precast concrete upper column to the top of the precast concrete lower column, fix the precast concrete upper column in the corresponding position with reliable supports, and tie the stirrups installed in Step 2; wherein, the protruding steel bars of the precast concrete upper and lower columns should be reasonably avoided in the core area of ​​the node and directly anchored.

[0030] Step 5: Pass the top continuous steel bar through the pre-reserved stirrups in the beam composite layer area and the node core area and tie it. Embed a section of corrugated pipe in the node core area to form an integral whole with the corrugated pipe pre-embedded in the precast concrete perforated beam. Then pour the UHPC node core area and set up a formwork so that the UHPC will not enter the beam composite layer.

[0031] Step 6: After the core area of ​​the UHPC node has been cured to sufficient strength, the precast concrete slab (or composite slab, double T slab, secondary beam) is hoisted onto the precast concrete perforated beam and fixed.

[0032] Step 7: Pour the beam composite layer and slab composite layer;

[0033] Step 8: Thread and tension the prestressing tendons in the corrugated pipes, and grout the corrugated pipes in the bonded parts of the beams and joints. Do not grout the unbonded prestressing tendon parts of the joints.

[0034] Step 9: Repeat the above production process to complete the bonded prestressed concrete perforated beam frame structure system.

[0035] Compared with the prior art, the advantages of the present invention are as follows:

[0036] 1. This invention combines precast concrete structures with post-tensioned bonded prestressed structures. It leverages the advantages of precast structures—convenient and rapid construction, high-quality build quality, energy efficiency, and environmental friendliness—while combining them with the advantages of post-tensioned bonded prestressed structures—which improve structural performance, reduce component cross-sectional height, decrease self-weight, enhance crack resistance, and provide self-healing—thereby improving the overall seismic performance of the frame structure. The unbonded prestressed tendons in the core area of ​​the joints provide the structure with self-resetting capabilities, enhancing the structure's integrity and toughness, and reducing post-earthquake repair costs.

[0037] 2. This invention uses UHPC material with excellent performance. Applying it to the core area of ​​the node can achieve reliable connection of precast beam and column components. It can not only improve the load-bearing capacity and seismic performance of the node, but also significantly reduce the anchorage length of steel bars and steel strands, and significantly reduce the amount of stirrups used in the core area of ​​the node. This avoids the congestion of steel bars in the core area of ​​the node, and greatly improves the efficiency of the production, transportation and installation of precast beam and column components. Attached Figure Description

[0038] Figure 1This is a structural schematic diagram of the precast prestressed concrete perforated beam frame structure system based on UHPC of the present invention.

[0039] Figure 2 This is a schematic diagram of the reinforcement of a two-span frame structure according to the present invention.

[0040] Figure 3 This is a schematic diagram of the material of a two-span frame structure according to the present invention.

[0041] Figure 4 Detailed construction diagram of the intermediate layer frame edge node of the present invention

[0042] Figure 5 Isometric view of the edge node of the intermediate layer frame of the present invention

[0043] Figure 6 Detailed diagram of node construction in the intermediate layer framework of this invention.

[0044] Figure 7 Axonometric view of the nodes in the intermediate layer frame of this invention. Detailed Implementation

[0045] To make the features, objectives and advantages of the present invention easier to understand, the present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0046] like Figure 1-7 As shown, the UHPC-connected post-tensioned bonded precast prestressed concrete perforated beam frame structure system of the present invention includes a precast concrete upper column (1), a precast concrete lower column (2), a post-tensioned bonded precast prestressed concrete perforated composite beam (3), a UHPC node core area (4), and a composite slab (17).

[0047] The precast concrete upper column (1) is provided with upper longitudinal main reinforcement (5), the precast concrete lower column (2) is provided with lower longitudinal main reinforcement (6), the post-tensioned bonded precast prestressed concrete perforated composite beam (3) is provided with precast concrete perforated beam (7) and beam composite layer (8) and post-tensioned bonded prestressed tendons (9), the bottom of the precast concrete perforated beam (7) is provided with ordinary steel bars (10), the top continuous steel bars (11) are provided in the beam composite layer (8), and the composite slab (17) is composed of precast concrete slab (18) and slab composite layer (19) poured on the slab;

[0048] The upper longitudinal main reinforcement (5) extends out of the bottom surface of the precast upper column (1) and is directly anchored in the core area (4) of the UHPC node; the lower longitudinal main reinforcement (6) extends out of the top surface of the precast lower column (2) and is directly anchored in the core area (4) of the UHPC node; the ordinary steel reinforcement (10) extends out of the end face of the precast concrete perforated beam (7) and is directly anchored in the core area (4) of the UHPC node.

[0049] The post-tensioned bonded precast prestressed concrete perforated composite beam (3) also includes a fully precast prestressed concrete perforated beam; the bonded prestressed tendons (9) include straight, broken, and curved prestressed tendons;

[0050] The bonded prestressed tendons (9) in the node core area (4) can be bonded, bonded, partially bonded and unbonded, or unbonded;

[0051] The post-tensioned bonded precast prestressed concrete perforated composite beam (3) is constructed in the cast beam composite layer (8), slab composite layer (19), and UHPC. Before the core area of ​​node (4), the construction calculation was carried out according to the force transmission mode adapted to the ordinary concrete open simply supported beam and the support setting. After pouring the core area of ​​node (4), beam composite layer (8) and slab composite layer (19), the concrete strength of the node and composite layer reached the design requirements, and the bonded prestressed tendons (9) were tensioned. After the tensioning was completed, the support was removed, and the construction stage calculation was carried out according to the unbonded frame beam. The cross section of the upper chord at the opening of the post-tensioned bonded precast prestressed concrete open composite beam is different before and after pouring the beam composite layer, slab composite layer and UHPC core area. The stress state is also different. The construction calculation of the upper and lower chords at the opening of the precast concrete open beam should be carried out. For the core area of ​​node with and without bond, under the normal service limit state, the calculation is carried out according to the effective prestress. Under the ultimate bearing limit state, the stress increment of the unbonded tendons is considered. Under seismic load, the recovery performance provided by the unbonded tendons is considered.

[0052] The post-tensioned bonded precast prestressed concrete perforated composite beam (3) is composed of a precast concrete perforated beam (7), a beam composite layer (8), and post-tensioned bonded prestressing tendons (9); the composite slab (17) is composed of a precast concrete slab (18) and a slab composite layer (19) cast on the slab.

[0053] The post-tensioned bonded prestressed tendon (9) is set in the corrugated pipe embedded in the precast concrete perforated beam (7) component, and passes through the corrugated pipe embedded in the beam composite layer (8) and the UHPC node core area (4) and extends out of the UHPC node core area (4) at both ends. The two ends are respectively fixed with clamps (15) and anchors (16).

[0054] The bottom surface of the precast concrete upper column (1), the top surface of the precast concrete lower column (2), and the end face of the post-tensioned bonded precast prestressed concrete perforated composite beam (3) are all provided with recessed grooves.

[0055] The precast concrete upper column (1) is fixed in the corresponding position by a reliable support (12);

[0056] The stirrups (13) in the precast concrete upper column (1), precast concrete lower column (2), and post-tensioned bonded precast prestressed concrete perforated composite beam (3) are divided into a dense zone and an undense zone. The stirrups (14) in the core area (4) of the UHPC node are arranged according to the design requirements. The shear bearing capacity of the core area is calculated according to the model of the inclined compression bar and truss, and the steel fibers in the UHPC are considered to be equivalent to horizontal stirrups and vertical longitudinal bars, and their contribution to the shear resistance of the core area of ​​the node is considered. At the same time, the beneficial contribution of bonded prestressed tendons to the shear resistance of the node is also considered.

[0057] The top surfaces of the precast concrete perforated beam (7) and the precast concrete slab (18) are provided with a rough surface layer.

[0058] The seismic design of this system includes the following steps:

[0059] Step 1: Design beams and columns according to existing specifications and invention patents;

[0060] Step 2: Verify the strength of the upper and lower chords at the opening of the precast concrete perforated beam before casting the beam composite layer, slab composite layer and UHPC node core area of ​​the precast prestressed concrete perforated composite beam.

[0061] Step 3: The opening position in the precast prestressed concrete perforated composite beam should be located in the middle 1 / 3 section as much as possible. When it is located in the end 1 / 3 section of the beam, the distance from the edge of the hole near the node to the inner edge of the node should be greater than 1.5 times the beam height.

[0062] A UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system, characterized by comprising the following steps:

[0063] Step 1: Construct precast concrete lower column (2), precast concrete upper column (1), precast concrete perforated beam (7), and precast concrete slab (18); among them, the longitudinal reinforcement extending from the precast concrete lower column (2) and precast concrete upper column (1) into the core area of ​​the node (4) needs to have sufficient anchorage length; the ordinary steel bars (10) extending from the precast concrete perforated beam (7) into the core area of ​​the node (4) need to have sufficient anchorage length; corrugated pipes are pre-embedded in the precast concrete perforated beam (7) according to the design position of the prestressed tendons (9);

[0064] Step 2: After the precast components are made, hoist the precast concrete lower column (2) and install it on the foundation, and then install an appropriate number of stirrups (14) on the extended longitudinal main reinforcement (6);

[0065] Step 3: Hoist the precast concrete perforated beam (7) to the top surface of the precast concrete lower column (2), so that the bottom surface of the precast concrete perforated beam (7) is flush with the top surface of the precast concrete lower column (2), and place the end of the precast concrete perforated beam (7) on the precast concrete lower column (2) and fix it with a support; wherein, the steel bars (10) extending from the precast concrete perforated beams (7) on both sides are reasonably avoided in the core area of ​​the node and directly anchored.

[0066] Step 4: Hoist the precast concrete upper column (1) directly above the precast concrete lower column (2), fix the precast concrete upper column (1) in the corresponding position with a reliable support (12), and tie the stirrups (14) installed in Step 2; wherein, the protruding steel bars of the precast concrete upper and lower columns are reasonably avoided in the core area of ​​the node and are directly anchored.

[0067] Step 5: Pass the top continuous steel bar (11) through the stirrup (13) reserved in the beam composite layer area and the node core area (4) and tie it. Embed a corrugated pipe in the node core area to form an integral whole with the corrugated pipe embedded in the precast concrete perforated beam (7). Then pour the UHPC node core area (4) and set the template so that the UHPC will not enter the beam composite layer (8).

[0068] Step 6: After the core area (4) of the UHPC node has been cured to a sufficient strength, the precast concrete slab (or composite slab, double T slab, secondary beam) (18) is hoisted onto the precast concrete beam (7) and fixed.

Claims

1. A UHPC-connected post-tensioned bonded precast prestressed concrete perforated beam frame structure system, comprising a precast concrete upper column (1), a precast concrete lower column (2), a post-tensioned bonded precast prestressed concrete perforated composite beam (3), a UHPC node core area (4), and a composite slab (17). Its features are, The precast concrete upper column (1) is provided with upper longitudinal main reinforcement (5), the precast concrete lower column (2) is provided with lower longitudinal main reinforcement (6), the post-tensioned bonded precast prestressed concrete perforated composite beam (3) is provided with precast concrete perforated beam (7), beam composite layer (8) and post-tensioned bonded prestressed tendons (9), the bottom of the precast concrete perforated beam (7) is provided with ordinary steel bars (10), and hanging bars (20) and steel mesh (21) are provided around the opening. The steel mesh is a welded steel mesh. The beam composite layer (8) is provided with top continuous steel bars (11). The composite slab (17) is composed of a precast concrete slab (18) and a slab composite layer (19) poured on the slab. The upper longitudinal main reinforcement (5) extends out of the bottom surface of the precast upper column (1) and is directly anchored in the core area (4) of the UHPC node; the lower longitudinal main reinforcement (6) extends out of the top surface of the precast lower column (2) and is directly anchored in the core area (4) of the UHPC node; the ordinary steel reinforcement (10) extends out of the end face of the precast concrete perforated beam (7) and is directly anchored in the core area (4) of the UHPC node. The post-tensioned bonded prestressed concrete perforated composite beam (3) also includes a fully prestressed prestressed concrete perforated beam; the bonded prestressed tendons (9) include straight, broken, and curved prestressed tendons; The bonded prestressed tendons (9) in the node core area (4) are bonded, partially bonded, unbonded, and unbonded; Before pouring the beam composite layer (8), slab composite layer (19), and UHPC node core area (4), the bonded precast prestressed concrete perforated composite beam (3) is constructed according to the force transmission mode adapted to the ordinary concrete perforated simply supported beam and support setup. After pouring the node core area (4), beam composite layer (8), and slab composite layer (19), the concrete strength of the node and composite layer reaches the design requirements, and the bonded prestressed tendons (9) are tensioned. After tensioning is completed, the supports are removed, and the construction stage is verified as an unbonded frame beam. Calculations should be made for the post-tensioned bonded precast prestressed concrete perforated composite beams. Before and after casting the beam composite layer, slab composite layer, and UHPC node core area, the upper chord section at the opening is different, and the stress state is also different. Construction verification calculations should be performed on the upper and lower chords at the opening of the precast concrete perforated beams. For the core area of ​​the node, the calculation should be based on the effective prestress under the normal serviceability limit state. Under the ultimate bearing limit state, the stress increment of the unbonded reinforcement should be considered. Under seismic loads, the recovery performance provided by the unbonded reinforcement should be considered. The post-tensioned bonded prestressed tendon (9) is set in the corrugated pipe embedded in the precast concrete perforated beam (7) component, and passes through the corrugated pipe embedded in the beam composite layer (8) and the UHPC node core area (4) and extends out of the UHPC node core area (4) at both ends. The two ends are respectively fixed with clamps (15) and anchors (16). The core areas of the edge nodes, middle nodes and corner nodes of the post-tensioned bonded precast prestressed concrete perforated beam frame structure system are all UHPC node core areas (4); The stirrups in the core area (4) of the UHPC node are arranged according to the design requirements. The shear bearing capacity calculation of the core area considers the steel fibers in the UHPC as equivalent to horizontal stirrups and vertical longitudinal bars, and considers their contribution to the shear resistance of the core area of ​​the node. At the same time, the beneficial contribution of bonded prestressed tendons to the core area of ​​the node is also considered. The construction method of the post-tensioned bonded prestressed concrete perforated beam frame structure system includes: The end of the precast concrete perforated beam (7) is placed on the precast concrete lower column (2), and the precast concrete upper column (1) is hoisted to the top of the precast concrete lower column (2). The area enclosed between the precast concrete perforated beam and the precast concrete lower and upper columns is the core area of ​​the UHPC node.

2. The UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system according to claim 1, characterized in that, The post-tensioned bonded precast prestressed concrete perforated composite beam (3) consists of a precast concrete perforated beam (7), a beam composite layer (8), and post-tensioned bonded prestressing tendons (9); the composite slab (17) consists of a precast concrete slab (18) and a slab composite layer (19) cast on the slab.

3. The UHPC-connected post-tensioned bonded prestressed concrete perforated frame structure system according to claim 1, characterized in that, The bottom surface of the precast concrete upper column (1), the top surface of the precast concrete lower column (2), and the end face of the post-tensioned bonded precast prestressed concrete perforated composite beam (3) are all provided with recessed grooves.

4. The UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system according to claim 1, characterized in that, The stirrups in the precast concrete upper column (1), precast concrete lower column (2), and post-tensioned bonded precast prestressed concrete perforated composite beam (3) are divided into a dense zone and a non-dense zone.

5. The UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system according to claim 1, characterized in that, The top surfaces of the precast concrete perforated beam (7) and the precast concrete slab (18) are provided with a rough surface layer.

6. A design method for a UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure system according to claim 1, characterized in that: The location of the opening in the beam should be in the middle 1 / 3 section as much as possible. When it is located in the end 1 / 3 section of the beam, the distance from the edge of the opening near the node to the inner edge of the node should be greater than 1.5 times the beam height.

7. A construction method for a post-tensioned bonded prestressed concrete perforated beam frame structure system with UHPC connection as described in any one of claims 1 to 5, characterized in that, Includes the following steps: Step 1: Construct precast concrete lower column (2), precast concrete upper column (1), precast concrete perforated beam (7), and precast concrete slab (18); among them, the longitudinal reinforcement extending from the precast concrete lower column (2) and precast concrete upper column (1) into the core area (4) of the node needs to be anchored with sufficient anchorage length; the ordinary steel bars (10) extending from the precast concrete perforated beam (7) into the core area (4) of the node need to be anchored with sufficient anchorage length; corrugated pipes are pre-embedded in the precast concrete perforated beam (7); Step 2: After the precast components are made, hoist the precast concrete lower column (2) and install it on the foundation, and then install an appropriate number of stirrups on the extended longitudinal main bars (6); Step 3: Hoist the precast concrete perforated beam (7) to the top surface of the precast concrete lower column (2), so that the bottom surface of the precast concrete perforated beam (7) is flush with the top surface of the precast concrete lower column (2), and place the end of the precast concrete perforated beam (7) on the precast concrete lower column (2) and fix it with a support; wherein, the steel bars (10) extending from the precast concrete perforated beams (7) on both sides are reasonably avoided in the core area of ​​the node and directly anchored. Step 4: Hoist the precast concrete upper column (1) directly above the precast concrete lower column (2), fix the precast concrete upper column (1) in the corresponding position with a reliable support (12), and tie the stirrups installed in Step 2; wherein, the protruding steel bars of the precast concrete upper and lower columns are reasonably avoided in the core area of ​​the node and are directly anchored. Step 5: Pass the top continuous steel bar (11) through the stirrups reserved in the beam composite layer area and the node core area (4) and tie it. Embed a corrugated pipe in the node core area to form an integral whole with the corrugated pipe embedded in the precast concrete perforated beam (7). Then pour the UHPC node core area (4) and set the template so that the UHPC will not enter the beam composite layer (8). Step 6: After the core area (4) of the UHPC node has been cured to a sufficient strength, the precast concrete slab, composite slab, double T slab or secondary beam is hoisted onto the precast concrete perforated beam (7) and fixed. Step 7: Pour the beam composite layer (8) and slab composite layer (19); Step 8: Thread and tension the prestressing tendons in the corrugated pipe (9), and grout the corrugated pipes in the bonded parts of the beam and joint. Do not grout the unbonded prestressing tendon parts of the joint. Step 9: Repeat the above production process to complete the bonded prestressed concrete perforated beam frame structure system.

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