A uhcp connected post-tensioned slow-bonding prefabricated prestressed concrete opening beam frame structure system and a design and construction method thereof

Abstract

The application discloses a UHPC connected post-tensioned slow-bonding prefabricated prestressed concrete open-hole beam frame structure system, which comprises a prefabricated concrete upper column, a prefabricated concrete lower column, a post-tensioned slow-bonding prefabricated prestressed concrete open-hole composite beam, a UHPC node core area and a composite slab. The upper longitudinal main reinforcement extends out of the bottom surface of the prefabricated upper column, the lower longitudinal main reinforcement extends out of the top surface of the prefabricated lower column, and the common steel bars extending out of the end surface of the prefabricated concrete beam are directly anchored in the UHPC node core area. The structure system not only is convenient and fast in on-site construction and improves the component installation efficiency, but also can greatly reduce the steel bar anchoring length, greatly reduce the amount of stirrups in the node core area, avoid the congestion of the steel bars in the node core area, reduce the component section height, reduce the self weight, improve the component crack resistance and self-recovery performance, and thus improve the seismic performance of the overall frame structure. The post-tensioned slow-bonding has the advantages of good durability and solves the defect of the non-dense grouting of the post-tensioned bonding.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of prefabricated prestressed assembly type building construction, in particular to a UHPC connected post-tensioned slow-bonding prefabricated prestressed concrete open-hole beam frame structure system and its design and construction method. BACKGROUND

[0002] The construction efficiency of cast-in-place structures is low, and the energy loss is high, and many limitations, which gradually cannot meet the development requirements of building industrialization. Prefabricated assembly type buildings have become the development direction of building industrialization due to their advantages of fast construction speed, factory production of components, reduction of on-site wet work and environmental pollution. After years of development and promotion, prefabricated assembly type concrete structures have been widely researched and used.

[0003] Prefabricated assembly type concrete frame structure refers to the structure in which beam and column components are prefabricated in a prefabrication plant and transported to the construction site for connection to form an overall structure. Compared with cast-in-place concrete structures, it has the advantages of fast construction speed, easy guarantee of component quality, good quality, less environmental pollution, saving of labor cost, and saving of a large amount of formwork and support, and is a structure form with very broad prospects. For wet connection assembly type concrete frame structures, the node construction form which is easy to construct and effectively guarantees the integrity is the key to the popularization and application. However, from the past earthquake disasters, the assembly type structure is severely damaged in the earthquake, and it is difficult to achieve the same seismic performance as the cast-in-place structure. In order to improve the integrity and reliability of the assembly type concrete frame node connection and achieve or exceed the seismic performance of the cast-in-place concrete structure, prestressing technology and UHPC material (Ultra High Performance Concrete, ultra high performance concrete) are introduced into the assembly type structure.

[0004] Post-tensioned slow-bonding prestressed assembly type concrete structure is a structure formed by assembling prefabricated components together to work together through tensioning of prestressed reinforcement, and has the characteristics of post-tensioned slow-bonding prestressed concrete structure and assembly type structure. The internal stress generated by prestress in the concrete section can partially or completely offset the stress in the section under the use load, delay the occurrence of cracks and improve the stiffness of the component. When unloaded, the cracks can be partially or completely closed, and the elastic recovery performance of the structure is good. At the same time, prestressed concrete can fully utilize the material strength of prestressed reinforcement and concrete, and reduce the self-weight of the structure. And the application of prestress helps to improve the performance and integrity of the assembly type structure, and promotes the application of the assembly type structure in large-span and heavy-load structures.

[0005] UHPC has excellent bonding performance, which can greatly reduce the anchorage length of steel bars and steel strands in it; it has high strength, which can reduce the amount of stirrups in the core area of the joint; using UHPC in the core area of the joint can make the structure simple and the overall framework good. The prestressed structure has excellent stress performance, and the application of UHPC in the core area of the joint forms a prefabricated prestressed framework structure. Further research on this structure is conducive to the further promotion and application of prefabricated prestressed concrete framework structure. SUMMARY

[0006] The purpose of the present application is to overcome the shortcomings of the prior art, combine the excellent performance of UHPC, and propose a UHPC connected post-tensioned slow-bonding prefabricated prestressed concrete open-hole beam framework structure system and its design and construction method. It combines three traditional structures of post-tensioned slow-bonding prestressed structure, fabricated structure and composite structure, and uses UHPC high-performance materials, so as to improve the seismic performance of prefabricated fabricated concrete framework structure.

[0007] The advantages of the present application mainly lie in the connection technology of prefabricated concrete open-hole beam column components and the steel bar connection technology between components. In terms of component connection technology, the beam column components are connected by UHPC with excellent performance to form a UHPC joint core area, which is more conducive to the realization of the seismic fortification requirements of strong joints and weak components, thereby improving the ductility of beam column joints and the seismic performance of the overall framework structure. In terms of steel bar connection technology, the steel bars between beam column components only need to be simply overlapped, and the overlap length is very small, thereby greatly saving the production time of prefabricated components and the installation time on site. Therefore, the UHPC connected post-tensioned slow-bonding prefabricated prestressed concrete open-hole beam framework structure system and its design and construction method proposed by the present application meet the green development strategy of China's building industrialization.

[0008] The technical problems solved by the present application can be realized by using the following technical solutions:

[0009] A UHPC connected post-tensioned slow-bonding prefabricated prestressed concrete open-hole beam framework structure system, comprising a prefabricated concrete upper column, a prefabricated concrete lower column, a post-tensioned slow-bonding prefabricated prestressed concrete open-hole composite beam, a UHPC joint core area and a composite slab.

[0010] The prefabricated concrete upper column is provided with upper longitudinal main reinforcement, the prefabricated concrete lower column is provided with lower longitudinal main reinforcement, the post-tensioned slow-bonding prefabricated prestressed concrete open-hole composite beam is provided with a prefabricated concrete open-hole beam, a beam composite layer and post-tensioned slow-bonding prestressed reinforcement, the bottom of the prefabricated concrete open-hole beam is provided with ordinary steel bars, and if necessary, hanging reinforcement and steel mesh can also be provided around the hole, and the steel mesh can also be a welded steel mesh; the beam composite layer is provided with top-through steel bars; and the composite slab is composed of a prefabricated 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 prefabricated upper column and is directly anchored in the UHPC node core area, the lower longitudinal main reinforcement extends out of the top surface of the prefabricated lower column and is directly anchored in the UHPC node core area, and the ordinary steel reinforcement extends out of the end surface of the prefabricated concrete opening beam and is directly anchored in the UHPC node core area;

[0012] The slow-bonding prestressed reinforcement includes straight-line, broken-line, and curved-line prestressed reinforcement.

[0013] The slow-bonding prestressed reinforcement in the node core area can be bonded, unbonded, or partially bonded and unbonded.

[0014] The post-tensioned slow-bonding prefabricated prestressed concrete opening composite beam is subjected to construction checking before pouring the beam composite layer, the plate composite layer, and the UHPC node core area, and the slow-bonding prestressed reinforcement is tensioned after the node and the composite layer concrete strength reaches the design requirement. After tensioning, the support is removed, and the construction stage checking is performed according to the frame beam. The prefabricated prestressed concrete opening composite beam has different cross sections and stress states at the hole opening before and after pouring the beam composite layer, the plate composite layer, and the UHPC node core area, and the upper and lower chord bars at the hole opening of the prefabricated concrete opening beam should be subjected to construction checking. In the construction checking, the unbonded prestressed reinforcement is calculated. In the normal use limit state and the bearing capacity limit state, the bonded prestressed reinforcement is calculated.

[0015] Further, the post-tensioned slow-bonding prefabricated prestressed concrete opening composite beam is composed of a prefabricated concrete opening beam, a beam composite layer, and a post-tensioned slow-bonding prestressed reinforcement.

[0016] Further, the post-tensioned slow-bonding prestressed reinforcement is pre-buried in the prefabricated concrete opening beam component according to the design position, passes through the UHPC node core area, and extends out of the UHPC node core area at both ends, and clamps and anchors are respectively arranged at both ends, one end is arranged outside the column, and the other end is arranged in the beam composite layer.

[0017] Further, the bottom surface of the prefabricated concrete upper column, the top surface of the prefabricated concrete lower column, and the end surface of the post-tensioned slow-bonding prefabricated prestressed concrete opening composite beam are provided with recessed grooves.

[0018] Further, the prefabricated concrete upper column is fixed at the corresponding position by reliable support.

[0019] Further, the stirrups in the precast concrete upper column, the precast concrete lower column and the post-tensioned slow-bonding precast prestressed concrete open-hole composite beam are divided into an encryption area and a non-encryption area, the stirrups in the UHPC node core area are arranged according to design requirements, the shear capacity of the core area is calculated according to the inclined strut and truss model, and the steel fibers in the UHPC are equivalent to horizontal stirrups and vertical longitudinal reinforcement, and the contribution of the steel fibers to the shear of the node core area is considered, and the beneficial contribution of the slow-bonding prestressed reinforcement to the shear of the node is considered.

[0020] Further, the top surface of the precast concrete open-hole beam and the precast concrete plate is provided with a rough surface layer.

[0021] The application also provides a design method of the system, comprising the following steps:

[0022] Step 1: The beam and the column are designed according to the existing specification and the invention patent;

[0023] Step 2: The strength of the upper chord and the lower chord at the hole of the precast concrete open-hole beam before pouring the beam composite layer, the plate composite layer and the UHPC node core area of the precast prestressed concrete open-hole composite beam is checked;

[0024] Step 3: The hole position in the precast prestressed concrete open-hole composite beam should be located in the 1 / 3 section of the span as much as possible, and when located in the 1 / 3 section of the beam end, the distance from the edge of the hole close to the node to the inner edge of the node should be greater than 1.5 times the beam height.

[0025] A post-tensioned slow-bonding precast prestressed concrete open-hole beam frame structure system connected by UHPC, comprising the following steps:

[0026] Step 1: The precast concrete lower column, the precast concrete upper column, the precast concrete open-hole beam and the precast concrete plate are manufactured; the precast concrete lower column and the precast concrete upper column are provided with longitudinal main reinforcement protruding out to meet the anchoring length requirement; the precast concrete open-hole beam is provided with ordinary steel reinforcement protruding out to also meet the anchoring length requirement; the slow-bonding prestressed reinforcement is embedded in the designed position when the precast concrete open-hole beam is manufactured, and sufficient length is reserved at both ends for convenient post-stage tensioning;

[0027] Step 2: After the precast component is cured, the precast concrete lower column is hoisted and installed on the foundation, and a sufficient number of stirrups are installed on the longitudinal main reinforcement protruding out of the lower column;

[0028] Step 3: hoist the prefabricated concrete open-hole beam to the top surface of the prefabricated concrete lower column, make the bottom surface of the prefabricated concrete open-hole beam flush with the top surface of the prefabricated concrete lower column, make the end of the prefabricated concrete open-hole beam rest on the prefabricated concrete lower column, and fix it with support; wherein the ordinary steel bars protruding from the two prefabricated concrete open-hole beams are reasonably avoided and directly anchored in the node core area according to the construction requirements;

[0029] Step 4: hoist the prefabricated concrete upper column to directly above the prefabricated concrete lower column, and fix the prefabricated concrete upper column in the corresponding position with reliable support, at this time, the stirrups installed in step 2 are tied together with the column longitudinal reinforcement; wherein the longitudinal reinforcement protruding from the prefabricated concrete upper and lower columns is reasonably avoided and directly anchored in the node core area;

[0030] Step 5: pass the top longitudinal steel bar through the stirrups reserved in the beam composite layer area and the node core area and tie them well, then tie the design position of the embedded and protruding slow-bonding prestressed tendon in the prefabricated concrete open-hole beam in the node core area, and for the unbonded part of the node, a sleeve is needed on the slow-bonding tendon, then pour the UHPC node core area, and set the formwork so that the UHPC does not enter the beam composite layer part;

[0031] Step 6: after the UHPC node core area is cured to sufficient strength, hoist the prefabricated concrete slab (or composite slab, double T slab, secondary beam) to the prefabricated concrete open-hole beam and fix it;

[0032] Step 7: pour the beam composite layer and the plate composite layer;

[0033] Step 8: tension the slow-bonding prestressed tendon;

[0034] Step 9: repeat the above manufacturing process to complete the post-tensioned slow-bonding prefabricated prestressed concrete open-hole beam frame structure system.

[0035] Compared with the prior art, the advantages of the present application are:

[0036] 1. The present application combines prefabricated assembly type concrete structure and post-tensioned slow-bonding prestressed structure together, which takes advantage of the prefabricated assembly type structure, such as convenient and fast construction, good construction quality, energy saving and environmental protection, and combines the post-tensioned slow-bonding prestressed structure to improve the structural performance, reduce the cross-sectional height of the component, reduce the self-weight, improve the crack resistance and self-recovery of the component, thereby improving the seismic performance of the overall frame structure. The post-tensioned slow-bonding has the advantage of good durability, and solves the disadvantage of non-compact grouting of post-tensioned bonding. The unbonded prestressed tendon in the node core area provides self-resetting capability for the structure, enhances the integrity and toughness of the structure, and reduces the repair cost after the earthquake.

[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, thereby avoiding the congestion of steel bars in the core area of ​​the node, and greatly improving the efficiency of the production, transportation and installation of precast beam and column components. Attached Figure Description

[0038] 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.

[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 the present 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 Figures 1-7 As shown, the UHPC-connected post-tensioned and loosely 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 and loosely bonded precast prestressed concrete perforated composite beam (3), a UHPC node core area (4), and a composite slab (17).

[0047] The prefabricated concrete upper column (1) is provided with upper longitudinal main reinforcement (5), the prefabricated concrete lower column (2) is provided with lower longitudinal main reinforcement (6), the post-tensioning slow-bonding prefabricated prestressed concrete open-hole composite beam (3) is provided with prefabricated concrete open-hole beam (7) and beam composite layer (8) and post-tensioning slow-bonding prestressed reinforcement (9), the bottom of the prefabricated concrete open-hole beam (7) is provided with ordinary reinforcement (10), the beam composite layer (8) is provided with top longitudinal reinforcement (11), and the composite slab (17) is composed of prefabricated 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 prefabricated upper column (1) and is directly anchored in the UHPC node core area (4), the lower longitudinal main reinforcement (6) extends out of the top surface of the prefabricated lower column (2) and is directly anchored in the UHPC node core area (4), and the ordinary reinforcement (10) extends out of the end surface of the prefabricated concrete open-hole beam (7) and is directly anchored in the UHPC node core area (4);

[0049] The slow-bonding prestressed reinforcement (9) includes straight-line, folded-line and curved-line prestressed reinforcement;

[0050] The slow-bonding prestressed reinforcement (9) can be bonded, unbonded or partially bonded and unbonded in the node core area;

[0051] The post-tensioning slow-bonding prefabricated prestressed concrete open-hole composite beam (3) is calculated according to the force transmission mode of ordinary concrete open-hole simply supported beam and support before pouring the beam composite layer (8), the slab composite layer (19) and the UHPC node core area (4), and the slow-bonding prestressed reinforcement (9) is tensioned after the node and the composite layer concrete strength reaches the design requirement; after tensioning, the support is removed, and the construction stage calculation is carried out according to the frame beam; the prefabricated prestressed concrete open-hole composite beam is different in cross-section and stress state at the hole opening before and after pouring the beam composite layer, the slab composite layer and the UHPC node core area, and the construction calculation of the upper and lower chord bars at the hole opening of the prefabricated concrete open-hole beam should be carried out; in the construction calculation, the unbonded prestressed reinforcement is calculated; in the normal use limit state and the bearing capacity limit state, the bonded prestressed reinforcement is calculated;

[0052] The post-tensioning slow-bonding prefabricated prestressed concrete open-hole composite beam (3) is composed of prefabricated concrete open-hole beam (7), beam composite layer (8) and post-tensioning slow-bonding prestressed reinforcement (9); the composite slab (17) is composed of prefabricated concrete slab (18) and slab composite layer (19) poured on the slab;

[0053] The post-tensioned slow-bonding prestressed tendon (9) is embedded in the prefabricated concrete open-hole beam (7) component according to the design position, passes through the UHPC node core area (4) and extends out of the UHPC node core area (4), and the two ends are respectively fixedly provided with clamps (15) and anchorage devices (16), one end is arranged outside the column, and the other end is arranged in the beam composite layer;

[0054] The bottom surface of the prefabricated concrete upper column (1), the top surface of the prefabricated concrete lower column (2), and the end surface of the post-tensioned slow-bonding prefabricated prestressed concrete open-hole composite beam (3) are provided with recesses;

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

[0056] The stirrups (13) in the prefabricated concrete upper column (1), the prefabricated concrete lower column (2), and the post-tensioned slow-bonding prefabricated prestressed concrete open-hole composite beam (3) are divided into dense areas and non-dense areas, the stirrups (14) in the UHPC node core area (4) are arranged according to design requirements, the shear capacity calculation of the core area is calculated according to the inclined strut and truss model, and the steel fibers in the UHPC are equivalent to horizontal stirrups and vertical longitudinal reinforcement, and the contribution of the steel fibers to the shear resistance of the node core area is considered, and the beneficial contribution of the slow-bonding prestressed tendon to the shear resistance of the node is also considered;

[0057] The top surface of the prefabricated concrete open-hole beam (7) and the prefabricated concrete slab (18) is provided with a rough surface layer.

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

[0059] Step 1: The beam and column are designed according to the existing specification and invention patent;

[0060] Step 2: Check the strength of the top chord at the hole of the prefabricated concrete open-hole beam before pouring the beam composite layer, the slab composite layer and the UHPC node core area of the prefabricated prestressed concrete open-hole composite beam;

[0061] Step 3: The hole position in the prefabricated prestressed concrete open-hole composite beam should be located as close to the 1 / 3 section of the span as possible, and when located in the 1 / 3 section of the beam end, 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 slow-bonding prefabricated prestressed concrete open-hole beam frame structure system, characterized in that it comprises the following steps:

[0063] Step 1: make prefabricated concrete lower column (2), prefabricated concrete upper column (1), prefabricated concrete opening beam (7), prefabricated concrete plate (18); wherein the prefabricated concrete lower column (2), the prefabricated concrete upper column (1) is reserved to extend the longitudinal main reinforcement to anchor into the node core area (4) to meet the requirement of anchoring length; the prefabricated concrete opening beam (7) is reserved to extend the ordinary steel bar (10) to anchor into the node core area (4) to also meet the requirement of anchoring length; the slow-bonding prestressed tendon (9) is embedded in the designed position when the prefabricated concrete opening beam (7) is made, and enough length is reserved at both ends for the convenience of later tensioning;

[0064] Step 2: after the prefabricated component is cured, the prefabricated concrete lower column (2) is hoisted and installed on the foundation, and enough number of stirrups (14) are installed on the longitudinal main reinforcement (6) extending out of the lower column (2);

[0065] Step 3: the prefabricated concrete opening beam (7) is hoisted to the top surface of the prefabricated concrete lower column (2), the bottom surface of the prefabricated concrete opening beam (7) is flush with the top surface of the prefabricated concrete lower column (2), the end of the prefabricated concrete opening beam (7) is placed on the prefabricated concrete lower column (2) and is fixed with support; wherein the ordinary steel bars (10) extending out of the prefabricated concrete opening beam (7) on both sides are reasonably avoided and directly anchored in the node core area according to the construction requirement;

[0066] Step 4: the prefabricated concrete upper column (1) is hoisted to directly above the prefabricated concrete lower column (2), the prefabricated concrete upper column (1) is fixed in the corresponding position with reliable support (12), at this time, the stirrups (14) installed in step 2 are tied together with the column longitudinal reinforcement; wherein the longitudinal reinforcement extending out of the prefabricated concrete upper and lower columns is reasonably avoided and directly anchored in the node core area;

[0067] Step 5: the top long steel bar (11) is passed through the stirrup (13) reserved in the beam composite layer area and the node core area (4) and is tied well, then the slow-bonding prestressed tendon (9) embedded and extending out of the prefabricated concrete opening beam is tied well in the node core area according to the designed position, the non-bonding part of the node needs to be sleeved on the slow-bonding tendon, and then the UHPC node core area (4) is poured and the formwork is set so that the UHPC does not enter the beam composite layer (8) part;

[0068] Step 6: after the UHPC node core area (4) is cured to enough strength, the prefabricated concrete flat plate (or composite plate, double T plate, secondary beam) (18) is hoisted to the prefabricated concrete opening beam (7) and is fixed;

[0069] Step 7: pour the beam composite layer (8) and the plate composite layer (19);

[0070] Step 8: tension the slow-bonding prestressed tendon (9);

[0071] Step 9: Repeat the above manufacturing process, and after completion, the frame structure system of the post-tensioned prestressed concrete beam with opening is finished.

Claims

1. A UHPC-connected post-tensioned and loosely 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 and loosely 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 slow-bonding prestressing tendon (9) includes straight, broken, and curved prestressing tendons; characterized in that the slow-bonding prestressing tendon (9) is bonded, bonded, partially bonded and unbonded, or unbonded in the core area of ​​the node; Before pouring the beam composite layer (8), slab composite layer (19), and UHPC node core area (4), the precast prestressed concrete perforated composite beam (3) is constructed and verified according to the force transmission mode adapted to the ordinary concrete perforated simply supported beam and support setting. 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 prestressed tendons (9) are tensioned. After tensioning, the support is removed, and the construction stage verification is carried out according to the frame beam. The precast prestressed concrete perforated composite beam has a different upper chord section at the opening before and after pouring the beam composite layer, slab composite layer, and UHPC node core area, and the stress state is also different. The upper and lower chords at the opening of the precast concrete perforated beam should be constructed and verified. During the construction verification, the calculation is carried out according to the unbonded prestressed tendons. In the normal serviceability limit state and the ultimate bearing capacity state, the calculation is carried out according to the bonded prestressed tendons. The post-tensioned bonded prestressing tendon (9) is pre-embedded in the precast concrete perforated beam (7) component according to the design position, passes through the core area (4) of the UHPC node and extends out of the core area (4) of the UHPC node at both ends. It is fixed with clamps (15) and anchors (16) at both ends respectively, with one end set on the outside of the column and the other end set in the beam composite layer. The core areas of the edge nodes, middle nodes and corner nodes of the post-tensioned and 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 the loosely bonded prestressed tendons to the shear resistance of the node is also considered. The construction method of the post-tensioned bonded precast prestressed concrete perforated beam frame structure system includes the following steps: 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 precast 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 precast 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 precast 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 precast 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 precast 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. The construction method of the UHPC-connected post-tensioned bonded precast prestressed concrete perforated beam frame structure system 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 concrete perforated beam (7), and precast concrete slab (18); among them, the longitudinal main reinforcement bars of the precast concrete lower column (2) and precast concrete upper column (1) that are reserved for extending into the core area of ​​the node (4) must meet the anchorage length requirements; the ordinary steel bars (10) of the precast concrete perforated beam (7) that are reserved for extending into the core area of ​​the node (4) must also meet the anchorage length requirements; when constructing the precast concrete perforated beam (7), the slow-bonded prestressing tendons (9) are pre-embedded in the design position, and sufficient length is reserved at both ends for easy tensioning later; Step 2: After the precast components have been cured, hoist the precast concrete lower column (2) and install it on the foundation, and install a sufficient number of stirrups on the longitudinal main reinforcement (6) extending from the lower column (2); 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 ordinary steel bars (10) extending from the precast concrete perforated beams (7) on both sides are reasonably avoided and directly anchored in the core area of ​​the node 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. Then tie the pre-embedded and extended slow-bonded prestressed tendons (9) in the precast concrete open beam in the node core area according to the design position. For the unbonded part of the node, a sleeve needs to be put on the slow-bonded tendon. 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: Tensioning the bonded prestressing tendons (9); Step 9: Repeat the above manufacturing process to complete the tension-bonded precast prestressed concrete perforated beam frame structure system.

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