A post-tensioned bonded co-tensioned prestressed concrete perforated beam frame structure with UHPC connection and its design and construction method.

Abstract

This invention discloses a post-tensioned bonded co-tensioned 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 co-tensioned prestressed concrete perforated composite beam, a UHPC node core area, and a composite slab. The upper longitudinal main reinforcement, lower longitudinal main reinforcement, ordinary steel bars, and pre-tensioned prestressing tendons are all directly anchored or bent and anchored within the UHPC node core area. This structural system not only facilitates and speeds up 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 self-healing performance of the components, thereby improving the seismic performance of the overall frame structure. The use of pre-tensioned prestressing tendons allows for less or no support during precast beam construction, and the secondary post-tensioning with bond improves the beam's load-bearing capacity and enhances the overall structural performance.

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 co-tensioned precast prestressed concrete perforated beam frame structure 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 integrity-ensuring joint construction methods are key to their widespread application. However, past earthquake disasters have shown that precast structures suffer 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 formed by assembling precast ordinary concrete members and precast pre-tensioned prestressed members together using tensioned prestressing tendons. They combine the characteristics of pre-tensioned prestressed concrete structures, 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 members. 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) structures, propose a UHPC-connected post-tensioned bonded prestressed concrete perforated beam frame structure, along with its design and construction methods. This invention combines three traditional structural methods: pre-tensioned prestressed, post-tensioned bonded prestressed, and prefabricated / overlay structures. Furthermore, it utilizes high-performance UHPC materials to improve the seismic performance of prefabricated concrete frame structures.

[0007] The advantages of this invention are mainly reflected in two aspects: the connection technology of precast prestressed concrete perforated beam-column members and the reinforcement connection technology between the members. Regarding the member connection technology, beam-column members are connected through high-performance UHPC (unrefined high-pressure concrete) to form a UHPC node core area, making it easier to meet the seismic fortification requirements of strong nodes and weak members, thereby improving the ductility of beam-column nodes and ultimately improving the seismic performance of the overall frame structure. Regarding the reinforcement connection technology, the reinforcement between beam-column members only requires simple lap splices with very short lap lengths, significantly saving the fabrication time and on-site installation time of precast members. Therefore, the UHPC-connected post-tensioned bonded co-tensioned prestressed concrete perforated beam-column 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 co-tensioned prestressed concrete perforated beam frame structure includes a precast concrete upper column, a precast concrete lower column, a post-tensioned bonded co-tensioned 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 pre-tensioned prestressed concrete perforated beam, a beam composite layer, and post-tensioned bonded prestressing tendons. The precast pre-tensioned prestressed concrete perforated beam is provided with ordinary steel bars and pre-tensioned prestressing tendons. If necessary, hanging bars or steel mesh can also be provided around 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; the ordinary steel bars and prestressed tendons extend out of the end face of the precast prestressed concrete perforated beam and are directly anchored in the core area of ​​the UHPC node.

[0012] The pre-tensioned prestressing tendons include straight or polygonal tendons, and the post-tensioned bonded prestressing tendons include straight, polygonal, and curved tendons;

[0013] The post-tensioned bonded co-tensioned prestressed concrete perforated composite beam can also be a fully prestressed perforated beam.

[0014] The post-tensioned bonded prestressing tendons in the core area of ​​the node can be bonded, partially bonded, unbonded, or unbonded.

[0015] The post-tensioned, bonded, co-tensioned prestressed concrete perforated composite beam is constructed and verified as a pre-tensioned, prestressed concrete perforated simply supported beam before the pouring of the beam composite layer, slab composite layer, and UHPC joint core area. After the pouring of the joint core area, beam composite layer, and slab composite layer, when the concrete strength of the joint and composite layer reaches the design requirements, the bonded prestressing tendons are tensioned. After tensioning, the construction stage verification is performed as a frame beam. The post-tensioned, bonded, co-tensioned prestressed concrete perforated composite beam is constructed and verified as a pre-tensioned, prestressed concrete perforated beam before the pouring of the beam composite layer, slab composite layer, and UHPC joint core area. The cross-section of the upper chord at the orifice differs before and after pouring in the core area, resulting in different stress states. Construction verification calculations should be performed on the upper and lower chords at the orifice of the precast prestressed concrete beam. For post-tensioned bonded prestressing tendons, the construction verification calculations are based on the effective prestress after prestressing is established. For bonded and unbonded sections in the core area of ​​the joint, calculations are performed based on the effective prestress under the serviceability limit state. Under the 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.

[0016] Furthermore, the post-tensioned bonded co-tensioned prestressed concrete perforated composite beam consists of a pre-tensioned prestressed concrete perforated beam, a beam composite layer, and post-tensioned bonded prestressing tendons.

[0017] Furthermore, the post-tensioned bonded prestressing tendons are placed inside the corrugated pipes embedded in the precast pre-tensioned prestressed concrete perforated beam member, 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.

[0018] 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.

[0019] Furthermore, the precast concrete upper column is fixed in the corresponding position using reliable supports.

[0020] 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 capacity of the core area is calculated according to the inclined compression bar 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.

[0021] Furthermore, the top surface of the precast prestressed concrete perforated beam and the precast concrete slab is provided with a rough surface layer.

[0022] This invention also provides a design method for the system, comprising the following steps:

[0023] Step 1: Design beams and columns according to existing specifications and invention patents;

[0024] Step 2: Verify the strength of the upper and lower chords at the opening of the pre-tensioned prestressed concrete perforated beam before the beam composite layer, slab composite layer and UHPC node core area of ​​the co-tensioned prestressed concrete perforated beam with bond after pouring.

[0025] Step 3: In post-tensioned bonded prestressed concrete composite beams with openings, the openings should be located in the middle third of the span as much as possible. When located in the end third 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.

[0026] A UHPC-connected post-tensioned bonded co-tensioned prestressed concrete perforated beam frame structure includes the following steps:

[0027] Step 1: Fabricate precast concrete lower columns, precast concrete upper columns, precast prestressed concrete perforated beams, and precast concrete slabs; among them, the longitudinal reinforcement of the precast concrete lower columns and precast concrete upper columns needs to be anchored into the core area of ​​the node with sufficient anchorage length; when precasting prestressed concrete perforated beams, the prestressed tendons are first tensioned on the platform, and the corrugated pipes required for bonded prestressed tendons are pre-embedded in the beam according to the design position, with sufficient length reserved on both sides, and then the concrete is poured. After the concrete has cured to sufficient strength, the prestressed tendons are released and sufficient anchorage length is reserved at the beam end;

[0028] Step 2: After the precast components have cured, 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;

[0029] Step 3: Hoist the precast prestressed concrete perforated beam to the top surface of the precast concrete lower column, making the bottom surface of the precast prestressed concrete perforated beam flush with the top surface of the precast concrete lower column. Place the end of the precast prestressed concrete perforated beam on the precast concrete lower column and fix it with supports. Since the beam already has prestressing effect, supports are not required. The ordinary steel bars and prestressed tendons extending from the precast prestressed concrete perforated beams on both sides should be reasonably avoided in the core area of ​​the node according to structural requirements and directly anchored or bent and anchored.

[0030] Step 4: Hoist the precast concrete upper column to the top of the precast concrete lower column, and fix the precast concrete upper column in the corresponding position with reliable supports. At this time, tie the stirrups installed in Step 2 to the column longitudinal reinforcement. The longitudinal reinforcements extending from the precast concrete upper and lower columns should be reasonably avoided in the core area of ​​the node and directly anchored.

[0031] Step 5: Pass the top continuous steel bar through the stirrups reserved in the beam composite layer area and the node core area and tie them. Embed a section of corrugated pipe in the node core area to form an integral whole with the corrugated pipe embedded in the pre-tensioned prestressed 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.

[0032] 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 prestressed concrete beam and fixed.

[0033] Step 7: Pour the beam composite layer and slab composite layer;

[0034] Step 8: After the composite concrete of the beam and slab has cured to sufficient strength, thread the prestressing tendons through the corrugated pipes and tension them. Grout the corrugated pipes in the bonded parts of the beam and joint. Do not grout the unbonded prestressing tendon parts of the joint.

[0035] Step 9: Repeat the above manufacturing process to complete the prestressed concrete perforated beam frame structure system with bonding.

[0036] Compared with the prior art, the advantages of the present invention are as follows:

[0037] 1. This invention combines precast concrete structures, prestressed prestressing, and bonded post-tensioned prestressed structures. Leveraging the advantages of precast structures—convenient and rapid construction, high-quality build quality, energy efficiency, and environmental friendliness—the invention combines bonded post-tensioned prestressed structures with improved structural performance, reduced component cross-sectional height, lighter weight, enhanced crack resistance, and self-healing properties, thereby improving the overall seismic performance of the frame structure. The use of prestressed tendons allows for less or no support during precast beam construction, while bonded post-tensioning increases the beam's load-bearing capacity and enhances the overall structural performance.

[0038] 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

[0039] Figure 1 This is a structural schematic diagram of the precast prestressed concrete perforated beam frame structure system based on UHPC of the present invention.

[0040] Figure 2 This is a schematic diagram of the reinforcement of a two-span frame structure according to the present invention.

[0041] Figure 3 This is a schematic diagram of the material of a two-span frame structure according to the present invention.

[0042] Figure 4 Detailed construction diagram of the intermediate layer frame edge node of the present invention

[0043] Figure 5 Isometric view of the edge node of the intermediate layer frame of the present invention

[0044] Figure 6 Detailed diagram of node construction in the intermediate layer framework of this invention.

[0045] Figure 7 Axonometric view of the nodes in the intermediate layer frame of this invention. Detailed Implementation

[0046] 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.

[0047] like Figure 1-7 As shown, the present invention provides a UHPC-connected post-tensioned bonded co-tensioned prestressed concrete perforated beam frame structure system, including a precast concrete upper column (1), a precast concrete lower column (2), a post-tensioned bonded co-tensioned prestressed concrete perforated composite beam (3), a UHPC node core area (4), and a composite slab (18).

[0048] 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 pre-tensioned prestressed concrete perforated beam (7) and beam composite layer (8) and post-tensioned bonded prestressing tendons (9), the precast pre-tensioned prestressed concrete perforated beam (7) is provided with ordinary steel bars (10) and pre-tensioned prestressing tendons (17), the beam composite layer (8) is provided with top continuous steel bars (11), and the composite slab (18) is composed of a precast concrete slab (19) and a slab composite layer (20) cast on the slab;

[0049] 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) and the prestressed tendon (17) extend out of the end face of the precast prestressed concrete perforated beam (7) and are directly anchored in the core area (4) of the UHPC node;

[0050] The pre-tensioned prestressing tendons (17) include straight or broken line tendons, and the post-tensioned bonded prestressing tendons (9) include straight, broken line, and curved tendons;

[0051] The post-tensioned bonded co-tensioned prestressed concrete perforated composite beam (3) can also be a fully prestressed perforated beam;

[0052] The post-tensioned bonded prestressing tendon (9) in the core area of ​​the node can be bonded, partially bonded, unbonded, or unbonded;

[0053] The post-tensioned bonded co-tensioned prestressed concrete perforated composite beam (3) is constructed and verified as a pre-tensioned prestressed concrete perforated simply supported beam before the pouring of the beam composite layer (8), slab composite layer (20), and UHPC node core area (4). After the pouring of the node core area (4), beam composite layer (8), and slab composite layer (20), when the concrete strength of the node and composite layer reaches the design requirements, the bonded prestressing tendons (9) are tensioned. After tensioning, the construction stage verification is performed as a frame beam. The post-tensioned bonded co-tensioned prestressed concrete perforated composite beam is constructed and verified as a pre-tensioned prestressed concrete perforated simply supported beam before the pouring of the beam composite layer (8), slab composite layer (20), and UHPC node core area (4). The cross section of the upper chord at the orifice is different before and after the pouring of the layer, slab composite layer and UHPC node core area, and the stress state is also different. Construction verification should be carried out on the upper and lower chords at the orifice of the precast prestressed concrete beam. After the prestress is established, the post-tensioned bonded prestressed tendons (9) are calculated based on the effective prestress during construction verification. For the bonded and unbonded parts of the node core area, the calculation is based on the effective prestress under the normal serviceability limit state. 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.

[0054] The post-tensioned bonded prestressed concrete perforated composite beam (3) consists of a pre-tensioned prestressed concrete perforated beam (7), a beam composite layer (8), and post-tensioned bonded prestressing tendons (9); the composite slab (18) consists of a precast concrete slab (19) and a slab composite layer (20) cast on the slab.

[0055] The post-tensioned bonded prestressed tendon (9) is placed in the corrugated pipe embedded in the precast pre-tensioned prestressed 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).

[0056] 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.

[0057] The precast concrete upper column (1) is fixed in the corresponding position by a reliable support (12);

[0058] 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 inclined compression bar model. 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.

[0059] The top surfaces of the precast prestressed concrete perforated beam (7) and the precast concrete slab (19) are provided with a rough surface layer.

[0060] The seismic design of this system includes the following steps:

[0061] Step 1: Design beams and columns according to existing specifications and invention patents;

[0062] Step 2: Verify the strength of the upper and lower chords at the opening of the pre-tensioned prestressed concrete perforated beam before the beam composite layer, slab composite layer and UHPC node core area of ​​the co-tensioned prestressed concrete perforated beam with bond after pouring.

[0063] Step 3: In post-tensioned bonded prestressed concrete composite beams with openings, the openings should be located in the middle third of the span as much as possible. When located in the end third 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.

[0064] A UHPC-connected post-tensioned bonded co-tensioned prestressed concrete perforated beam frame structure, characterized by comprising the following steps:

[0065] Step 1: Construct precast concrete lower column (2), precast concrete upper column (1), precast prestressed concrete perforated beam (7), and precast concrete slab (19); among them, the precast concrete lower column (2) and precast concrete upper column (1) need to reserve sufficient anchorage length for the longitudinal reinforcement extending into the core area (4) of the node; when constructing the prestressed concrete perforated beam (7), the prestressed tendons (17) are first tensioned on the platform, and the corrugated pipes required for the bonded prestressed tendons (9) are pre-embedded in the beam according to the design position, and sufficient length is reserved on both sides, and then the concrete is poured. When the concrete has been cured to sufficient strength, the prestressed tendons (17) are released and sufficient anchorage length is reserved at the beam end;

[0066] Step 2: After the precast components have been cured, 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);

[0067] Step 3: Hoist the precast prestressed concrete perforated beam (7) to the top surface of the precast concrete lower column (2), so that the bottom surface of the precast prestressed concrete perforated beam (7) is flush with the top surface of the precast concrete lower column (2), and place the end of the precast prestressed concrete perforated beam (7) on the precast concrete lower column (2) and fix it with a support. Since the beam has been prestressed, it can be without a support. Among them, the ordinary steel bars (10) and prestressed tendons (17) extending from the prestressed concrete perforated beams (7) on both sides should be reasonably avoided in the core area of ​​the node and directly anchored or bent and anchored according to the structural requirements.

[0068] Step 4: Hoist the precast concrete upper column (1) directly above the precast concrete lower column (2), and fix the precast concrete upper column (1) in the corresponding position with a reliable support (12). At this time, tie the stirrups (14) installed in step 2 together with the column longitudinal reinforcement. The longitudinal reinforcements extending from the precast concrete upper and lower columns are reasonably avoided in the core area of ​​the node and are directly anchored.

[0069] 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 pre-tensioned prestressed 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).

[0070] 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) (19) is hoisted onto the precast prestressed concrete perforated beam (7) and fixed.

[0071] Step 7: Pour the beam composite layer (8) and slab composite layer (20);

[0072] Step 8: After the concrete of the beam composite layer (8) and slab composite layer (20) has been cured to sufficient strength, the prestressing tendons (9) are threaded through the corrugated pipe and tensioned. Grouting is performed in the corrugated pipes of the bonded parts of the beam and the joint. No grouting is performed on the unbonded prestressing tendon parts of the joint.

[0073] Step 9: Repeat the above manufacturing process to complete the prestressed concrete perforated beam frame structure system with bonding.

[0074] The above description is merely an exemplary description of the present invention. Obviously, the specific implementation of the present invention is not limited to the above-described manner. That is, the description is not restrictive. Without departing from the inventive concept and technical solution of the present invention, the present invention can be easily improved, changed or replaced in various ways, and all such improvements and changes fall within the protection scope of the present invention.

Claims

1. A UHPC-connected post-tensioned bonded co-tensioned prestressed concrete perforated beam frame structure system, comprising a precast concrete upper column (1), a precast concrete lower column (2), a post-tensioned bonded co-tensioned prestressed concrete perforated composite beam (3), a UHPC node core area (4), and a composite slab (18). 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 pre-tensioned prestressed concrete perforated beam (7), beam composite layer (8) and post-tensioned bonded prestressing tendons (9), the precast pre-tensioned prestressed concrete perforated beam (7) is provided with ordinary steel bars (10) and pre-tensioned prestressing tendons (17), and hanging bars (21) or steel mesh (22) are provided around the opening, the steel mesh is welded steel mesh, the beam composite layer (8) is provided with top continuous steel bars (11), the composite slab (18) is composed of precast concrete slab (19) and slab composite layer (20) 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) and the prestressed tendon (17) extend out of the end face of the precast prestressed concrete perforated beam (7) and are directly anchored in the core area (4) of the UHPC node; The pre-tensioned prestressing tendons (17) include straight or broken line tendons, and the post-tensioned bonded prestressing tendons (9) include straight, broken line, and curved tendons; The post-tensioned bonded prestressed concrete perforated composite beam (3) is a fully prestressed perforated beam; The post-tensioned bonded prestressed tendons (9) in the node core area are bonded, partially bonded, unbonded, and unbonded; The post-tensioned bonded co-tensioned prestressed concrete perforated composite beam (3) is constructed and verified as a pre-tensioned prestressed concrete perforated simply supported beam before the pouring of the beam composite layer (8), slab composite layer (20), and UHPC node core area (4). After the pouring of the node core area (4), beam composite layer (8), and slab composite layer (20), when the concrete strength of the node and composite layer reaches the design requirements, the bonded prestressing tendons (9) are tensioned. After tensioning, the construction stage verification is performed as a frame beam. The post-tensioned bonded co-tensioned prestressed concrete perforated composite beam is constructed and verified as a pre-tensioned prestressed concrete perforated simply supported beam before the pouring of the beam composite layer (8), slab composite layer (20), and UHPC node core area (4). The cross section of the upper chord at the orifice is different before and after the pouring of the layer, slab composite layer and UHPC node core area, and the stress state is also different. Construction verification should be carried out on the upper and lower chords at the orifice of the precast prestressed concrete beam. After the prestress is established, the post-tensioned bonded prestressed tendons (9) are calculated based on the effective prestress during construction verification. For the bonded and unbonded parts of the node core area, the calculation is based on the effective prestress under the normal serviceability limit state. 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. The post-tensioned bonded prestressed tendon (9) is placed in the corrugated pipe embedded in the precast pre-tensioned prestressed 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 co-tensioned 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. The construction method of the co-tensioned prestressed concrete perforated beam frame structure system includes: The end of the precast prestressed 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 prestressed 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 co-tensioned prestressed concrete perforated beam frame structure system according to claim 1, characterized in that, The post-tensioned bonded prestressed concrete perforated composite beam (3) consists of a pre-tensioned prestressed concrete perforated beam (7), a beam composite layer (8), and post-tensioned bonded prestressing tendons (9); the composite slab (18) consists of a precast concrete slab (19) and a slab composite layer (20) cast on the slab.

3. The UHPC-connected post-tensioned bonded co-tensioned prestressed concrete perforated beam 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 co-tensioned 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 co-tensioned prestressed concrete perforated beam frame structure system according to claim 1, characterized in that, The top surfaces of the precast prestressed concrete perforated beam (7) and the precast concrete slab (19) are provided with a rough surface layer.

6. A design method for a post-tensioned, bonded, co-tensioned prestressed concrete perforated beam frame structure system with UHPC connection 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. The construction method of the UHPC-connected post-tensioned bonded co-tensioned prestressed concrete perforated beam frame structure according to 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 prestressed concrete perforated beam (7), and precast concrete slab (19); among them, the precast concrete lower column (2) and precast concrete upper column (1) need to reserve sufficient anchorage length for the longitudinal reinforcement extending into the core area (4) of the node; when precasting prestressed concrete beam, the prestressed tendons (17) are tensioned on the platform first, and the corrugated pipes required for the bonded prestressed tendons (9) are embedded in the beam according to the design position, and sufficient length is reserved on both sides, and then the concrete is poured. When the concrete is cured to sufficient strength, the prestressed tendons (17) are tensioned and sufficient anchorage length is reserved at the beam end; Step 2: After the precast components have been cured, 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 reinforcement (6); Step 3: Hoist the precast prestressed concrete perforated beam (7) to the top surface of the precast concrete lower column (2), so that the bottom surface of the precast prestressed concrete perforated beam (7) is flush with the top surface of the precast concrete lower column (2), and place the end of the precast prestressed concrete perforated beam (7) on the precast concrete lower column (2) and fix it with a support. Since the beam has been prestressed, it can be without a support. Among them, the ordinary steel bars (10) and prestressed tendons (17) extending from the prestressed concrete perforated beams (7) on both sides should be reasonably avoided in the core area of ​​the node and directly anchored or bent and anchored according to the structural requirements. Step 4: Hoist the precast concrete upper column (1) directly above the precast concrete lower column (2), and fix the precast concrete upper column (1) in the corresponding position with a reliable support (12). At this time, tie the stirrups installed in step 2 together with the column longitudinal reinforcement. The longitudinal reinforcements extending from the precast concrete upper and lower columns should be reasonably avoided in the core area of ​​the node and 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 prestressed 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 prestressed concrete beam and fixed. Step 7: Pour the beam composite layer (8) and slab composite layer (20); Step 8: After the concrete of the beam composite layer (8) and slab composite layer (20) has been cured to sufficient strength, the prestressing tendons (9) are threaded through the corrugated pipe and tensioned. Grouting is performed in the corrugated pipes of the bonded parts of the beam and the joint. No grouting is performed on the unbonded prestressing tendon parts of the joint. Step 9: Repeat the above manufacturing process to complete the prestressed concrete perforated beam frame structure system with bonding.

Images