A uhp connected precast prestressed concrete frame structure system and its design and construction method

Abstract

The application discloses a prefabricated prestressed concrete frame structure system connected by UHPC, which comprises prefabricated concrete upper columns, prefabricated concrete lower columns, prefabricated prestressed concrete composite beams, UHPC node core areas and composite slabs. The upper longitudinal main reinforcement extends out of the bottom surface of the prefabricated upper columns and is directly anchored in the UHPC node core areas, the lower longitudinal main reinforcement extends out of the top surface of the prefabricated lower columns and is directly anchored in the UHPC node core areas, the prestressed reinforcement and the common reinforcement extend out of the end surface of the prefabricated prestressed concrete beams and are directly anchored or bent and anchored in the UHPC node core areas. The structure system not only is convenient and fast in on-site construction and improves the installation efficiency of components, but also can greatly reduce the anchoring length of the reinforcement, greatly reduce the amount of stirrups in the node core areas, avoid the congestion of the reinforcement in the node core areas, reduce the cross-section height of the components, reduce the self weight, improve the crack resistance of the components and thus improve the seismic performance of the overall frame structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of prefabricated prestressed assembly type building construction, in particular, to a prefabricated prestressed concrete frame structure system connected by UHPC and a design and construction method thereof. BACKGROUND

[0002] The construction efficiency of cast-in-place structure is low, and the energy loss is high, and many limitations, which gradually cannot meet the development requirements of building industrialization. Prefabricated assembly type building has become the development direction of building industrialization due to its 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 structure has been widely researched and used.

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

[0004] The prestressed assembly type concrete structure is divided into pretensioned prestressed assembly type concrete structure and post-tensioned prestressed assembly type concrete structure. The pretensioned prestressed assembly type concrete structure is to tension the prestressed tendon before the component is made and then pour the component. The post-tensioned prestressed assembly type concrete structure is to pre-embed the prestressed tendon or corrugated pipe before pouring the concrete and then tension the prestressed tendon, and finally assemble the components together. 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, the prestressed concrete can fully utilize the material strength of the prestressed tendon and the 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 prestressed bars therein; 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 the structure is beneficial 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 prefabricated prestressed concrete framework structure system and its design and construction method. It combines the three traditional structures of pretensioned or post-tensioned 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 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 likely to achieve the seismic fortification requirement of strong node and weak component, thereby improving the ductility of beam-column joint 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 prefabricated prestressed concrete framework structure system and its construction method proposed by the present application meet the green development strategy of building industrialization in China.

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

[0009] A UHPC connected prefabricated prestressed concrete framework structure system, comprising a prefabricated concrete upper column, a prefabricated concrete lower column, a prefabricated prestressed concrete 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 prefabricated prestressed concrete composite beam is provided with a prefabricated prestressed concrete beam and a beam composite layer, the prefabricated prestressed concrete beam is provided with prestressed reinforcement and ordinary reinforcement, and the beam composite layer is provided with top longitudinal reinforcement. The composite slab is composed of a prefabricated concrete slab and a slab composite layer poured 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, the prestressed reinforcement and the ordinary steel reinforcement extend out of the end surface of the prefabricated prestressed concrete beam and are directly anchored or indirectly anchored in the UHPC node core area;

[0012] The prefabricated prestressed concrete composite beam can also be a fully prefabricated prestressed concrete beam; the prestressed reinforcement includes pretensioned straight or folded line prestressed reinforcement and post-tensioned bonded, unbonded or slow-bonded straight, folded or curved line prestressed reinforcement;

[0013] The prefabricated prestressed concrete composite beam is calculated as a prestressed concrete simply supported beam before pouring the beam composite layer, the plate composite layer and the UHPC node core area, and is calculated as a frame beam after pouring the UHPC node core area, the beam composite layer and the plate composite layer; for the unbonded prestressed beam, the effective prestress is used for calculation at the normal use limit state, and the stress increment of the unbonded reinforcement is considered at the ultimate bearing limit state.

[0014] Further, the prefabricated prestressed concrete composite beam is composed of a prefabricated prestressed concrete beam and a beam composite layer; the composite plate is composed of a prefabricated concrete plate and a plate composite layer poured on the plate.

[0015] 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 prefabricated prestressed concrete composite beam are provided with recessed grooves (U-shaped grooves can also be arranged at the beam end, and constructional shear reinforcement can be arranged if necessary).

[0016] Further, the prefabricated concrete upper column is fixed at the corresponding position by a reliable support.

[0017] Further, the stirrups in the prefabricated concrete upper column, the prefabricated concrete lower column and the prefabricated prestressed concrete composite beam are divided into dense areas and non-dense areas, the stirrups in the UHPC node core area are arranged according to design requirements, the shear bearing capacity of the core area is calculated according to the diagonal compression 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.

[0018] Further, the top surface of the prefabricated prestressed concrete beam and the top surface of the prefabricated concrete plate are provided with a rough surface layer.

[0019] The application also provides a design method of the system, which comprises the following steps:

[0020] Step 1: the beam and the column are designed according to the existing specifications and the invention patent;

[0021] Step 2: the seismic design of the node needs to be carried out according to the following method, and the horizontal shear bearing capacity V of the node is calculatedjh :

[0022] (a) The shear capacity of the frame beam-column joint shall comply with the following provisions:

[0023]

[0024] V jh = V sh + V ch + V fh

[0025] V sh = a · A sjh · f yj

[0026]

[0027] V fh = η λ f h b b c

[0028]

[0029] In the formula: A sjh — The area of the stirrup in the core area of the joint;

[0030] f yj — The design value of the yield strength of the stirrup in the core area of the joint;

[0031] b j — The effective width of the joint;

[0032] h c — The height of the column;

[0033] A sb — The sum of the area of the longitudinal reinforcement at the top and bottom of the beam;

[0034] b b — The width of the beam;

[0035] h b — The height of the beam;

[0036] f c — The design value of the axial compressive strength of concrete;

[0037] η — The effective coefficient of UHPC steel fiber;

[0038] l — The length of UHPC steel fiber;

[0039] d — The diameter of UHPC steel fiber;

[0040] V f — The volume content of UHPC steel fiber;

[0041] Step 3: At the intermediate nodes of the frame's intermediate floors, the upper longitudinal reinforcement of the frame beams should penetrate through the intermediate nodes. The diameter of each longitudinal reinforcement beam penetrating the central column, for seismic grades I, II, and III, when the column has a rectangular cross-section, should not exceed the smaller of 1 / 18 of the column's cross-sectional dimension in that direction and x. x is calculated using the following formula:

[0042]

[0043] In the formula: f y — This represents the design value of the yield strength of the longitudinal reinforcement bars of the beam that run through the central column.

[0044] A precast prestressed concrete frame structure system with UHPC connection includes the following steps:

[0045] Step 1: Fabricate precast concrete lower columns, precast concrete upper columns, precast prestressed concrete beams, and precast concrete slabs. Sufficient anchorage length must be reserved for the longitudinal reinforcement extending from the precast concrete lower and upper columns and anchoring it into the core area of ​​the joint. Sufficient anchorage length must also be reserved for the ordinary steel bars and prestressed tendons extending from the precast prestressed concrete beams and anchoring them into the core area of ​​the joint. When fabricating precast prestressed concrete beams, if the prestressed tendons are pre-tensioned, the prestressed tendons are tensioned on the platform before pouring concrete. Once the concrete reaches sufficient strength, the prestressed tendons are released, and sufficient anchorage length is reserved at the ends of the precast beam. If the prestressed tendons are post-tensioned, the post-tensioned tendons are pre-embedded in the designed position (corrugated pipes need to be pre-embedded if there is bonding), with sufficient length reserved at both ends, before pouring concrete. Post-tensioning is performed when the concrete reaches the designed tensile strength (grouting is required if there is bonding).

[0046] 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;

[0047] Step 3: Hoist the precast prestressed concrete beam to the top surface of the precast concrete lower column, making the bottom surface of the precast prestressed concrete beam flush with the top surface of the precast concrete lower column. Place the ends of the precast prestressed concrete beam on the precast concrete lower column and fix them with supports. Since the beam already has prestress, supports may not be necessary. The steel bars extending from the precast concrete beams on both sides should be reasonably avoided in the core area of ​​the joint and directly anchored. The extending prestressed tendons should be reasonably avoided in the core area of ​​the joint and anchored in a straight line or by bending.

[0048] 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.

[0049] Step 5: pass the top longitudinal reinforcement through the reserved stirrup of the superimposed layer and the node core area, and then pour the UHPC node core area, and set the formwork so that the UHPC does not enter the beam superimposed layer part;

[0050] Step 6: hoist the prefabricated concrete slab (or superimposed slab, double T slab, secondary beam) to the prefabricated prestressed concrete beam and fix it;

[0051] Step 7: pour the beam superimposed layer and the slab superimposed layer;

[0052] Step 8: repeat the above manufacturing process to complete the prefabricated prestressed concrete frame structure system.

[0053] Compared with the prior art, the advantages of the present application are:

[0054] 1. The prefabricated assembly type concrete structure and the prestressed structure are combined together in the present application, and on the basis of the advantages of the prefabricated assembly type structure, such as convenient and fast construction, good construction quality, energy saving and environmental protection, the prestressed structure can improve the service performance of the structure, reduce the cross section height of the component, reduce the self weight, and improve the crack resistance of the component, so as to improve the seismic performance of the overall frame structure.

[0055] 2. The UHPC material with excellent performance is used in the present application, and is applied in the node core area, so that the reliable connection of the prefabricated beam column component can be realized, the bearing capacity and the seismic performance of the node can be improved, the anchoring length of the steel bar and the prestressed tendon can be greatly reduced, and the amount of the stirrup in the node core area can be significantly reduced, so that the congestion of the steel bars in the node core area is avoided, and the manufacturing, transportation and installation efficiency of the prefabricated beam column component is greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0056] Figure 1 The structure schematic view of the UHPC connected prefabricated prestressed concrete frame structure system of the present application

[0057] Figure 2 The reinforcement schematic view of a two-span frame structure of the present application

[0058] Figure 3 The material schematic view of a two-span frame structure of the present application

[0059] Figure 4 The detailed view of the edge node structure of the intermediate layer frame of the present application

[0060] Figure 5 The isometric view of the edge node structure of the intermediate layer frame of the present application

[0061] Figure 6 The detailed view of the middle node structure of the intermediate layer frame of the present application

[0062] Figure 7 Axonometric view of the nodes in the intermediate layer frame of the present invention. Detailed Implementation

[0063] 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.

[0064] like Figures 1-7 As shown, the precast prestressed concrete frame structure system with UHPC connection according to the present invention includes a precast concrete upper column (1), a precast concrete lower column (2), a precast prestressed concrete composite beam (3), a UHPC node core area (4), and a composite slab (5).

[0065] The precast concrete upper column (1) is provided with upper longitudinal main reinforcement (6), the precast concrete lower column (2) is provided with lower longitudinal main reinforcement (7), the precast prestressed concrete composite beam (3) is provided with precast prestressed concrete beam (8) and beam composite layer (9), the precast prestressed concrete beam (8) is provided with prestressed tendons (10) and ordinary steel bars (11), the beam composite layer (9) is provided with top continuous steel bars (12), and the composite slab (5) is composed of precast concrete slab (13) and slab composite layer (14) cast on the slab;

[0066] The upper longitudinal main reinforcement (6) 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 (7) 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 prestressed tendon (10) and ordinary steel bar (11) extend out of the end face of the precast prestressed concrete beam (8) and are directly anchored or bent and anchored in the core area (4) of the UHPC node;

[0067] The precast prestressed concrete composite beam (3) can also be a fully precast prestressed concrete beam; the prestressing tendons (10) include pre-tensioned straight or broken-line prestressing tendons and post-tensioned straight, broken, or curved prestressing tendons with or without bonding or with slow bonding.

[0068] The precast prestressed concrete composite beam (3) is calculated as a prestressed concrete simply supported beam before the pouring of the beam composite layer (9), the slab composite layer (14) and the UHPC node core area (4). After the pouring of the UHPC node core area (4), the beam composite layer (9) and the slab composite layer (14), it is calculated as a frame beam. For unbonded prestressed beams, the effective prestress is calculated under the normal serviceability limit state, and the stress increment of the unbonded reinforcement is considered under the ultimate bearing limit state.

[0069] The prefabricated prestressed concrete composite beam (3) is composed of a prefabricated prestressed concrete beam (8) and a beam composite layer (9); the composite slab (5) is composed of a prefabricated concrete slab (13) and a slab composite layer (14) poured on the slab.

[0070] 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 prefabricated prestressed concrete composite beam (3) are all provided with a recessed groove (a U-shaped groove can also be provided at the beam end, and a construction shear steel bar can be provided if necessary).

[0071] The prefabricated concrete upper column (1) is fixed in the corresponding position by a reliable support (15).

[0072] The stirrups (16) in the prefabricated concrete upper column (1), the prefabricated concrete lower column (2), and the prefabricated prestressed concrete composite beam (3) are divided into a densified area and a non-densified area, the stirrups (17) in the UHPC node core area (4) are arranged according to design requirements, the shear bearing capacity of the core area is calculated according to the softened strut-and-tie 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.

[0073] The top surface of the prefabricated prestressed concrete beam (8) and the prefabricated concrete slab (13) is provided with a rough surface layer.

[0074] The seismic design of the system includes the following steps:

[0075] Step 1: The beam and column are designed according to existing specifications and invention patents;

[0076] Step 2: The seismic design of the node needs to be carried out according to the following method: the horizontal shear bearing capacity V of the node is calculated jh ;

[0077] Step 3: The diameter of each longitudinal steel bar penetrating the middle column should not be greater than the smaller value of 1 / 18 of the sectional size of the column in that direction and x.

[0078] A UHPC connected prefabricated prestressed concrete frame structure system, characterized in that it comprises the following steps:

[0079] Step 1: make prefabricated concrete lower column (2), prefabricated concrete upper column (1), prefabricated prestressed concrete beam (8), prefabricated concrete slab (13); wherein the prefabricated concrete lower column (2), the prefabricated concrete upper column (1) extends the longitudinal reinforcement anchoring into the node core area (4) and needs to reserve enough anchoring length; the prefabricated prestressed concrete beam (8) extends the ordinary steel bar and the prestressed reinforcement anchoring into the node core area (4) and needs to reserve enough anchoring length; wherein when making the prefabricated prestressed concrete beam (8), the prestressed reinforcement (10) is the first tension prestressed reinforcement, first tension prestressed reinforcement (10) on the pedestal, then pour the concrete, when the concrete reaches enough strength, release the tension prestressed reinforcement (10) and reserve enough anchoring length at the end of the prefabricated beam; the prestressed reinforcement (10) is the post-tensioned prestressed reinforcement, first embed the post-tensioned prestressed reinforcement in the designed position (need to embed the bellows with adhesion), and reserve enough length at both ends, then pour the concrete, when the concrete reaches the designed tension strength, tension the post-tensioned prestressed reinforcement (need to grout with adhesion);

[0080] Step 2: after the prefabricated components are completed, hoist the prefabricated concrete lower column (2) and install it on the foundation, then install the appropriate number of stirrups (17) on the extended longitudinal main reinforcement (7);

[0081] Step 3: hoist the prefabricated prestressed concrete beam (8) to the top surface of the prefabricated concrete lower column (2), make the bottom surface of the prefabricated prestressed concrete beam (8) flush with the top surface of the prefabricated concrete lower column (2), make the end of the prefabricated prestressed concrete beam (8) rest on the prefabricated concrete lower column (2) and be fixed with support, since there is prestressed action in the beam, support can also be omitted; wherein the steel bars (11) extended from the two prefabricated concrete beams (8) are reasonably avoided in the node core area and directly anchored, the prestressed reinforcement (10) extended from the two prefabricated concrete beams (8) is reasonably avoided in the node core area and anchored in a straight line or a bent line;

[0082] Step 4: hoist the prefabricated concrete upper column (1) to the directly above the prefabricated concrete lower column (2), fix the prefabricated concrete upper column (1) in the corresponding position with reliable support (15), and bind the stirrups (17) installed in step 2; wherein the extended steel bars of the prefabricated concrete upper and lower columns are reasonably avoided in the node core area and directly anchored;

[0083] Step 5: pass the top long steel bar (12) through the reserved stirrups (16) of the composite layer and the node core area (4) and bind them, then pour the UHPC node core area (4) and set the formwork so that the UHPC does not enter the beam composite layer (9) part;

[0084] Step 6: hoist the prefabricated concrete flat plate (or composite plate, double T plate, secondary beam) (13) to the prefabricated prestressed concrete beam (8) and fix it;

[0085] Step 7: pouring the beam superimposed layer (9) and the plate superimposed layer (14);

[0086] Step 8: repeating the above manufacturing process to complete the prefabricated prestressed concrete frame structure system.

[0087] The above is only an exemplary description of the present application, and it is obvious that the specific implementation of the present application is not limited by the above method, that is, the description is not limited, and the present application can be easily improved, changed or replaced without departing from the method concept and technical solution of the present application, and these improvements and changes all belong to the protection scope of the present application.

Claims

1. A UHPC connected precast prestressed concrete frame structure system, comprising a precast concrete upper column (1), a precast concrete lower column (2), a precast prestressed concrete composite beam (3), a UHPC joint core area (4) and a composite slab (5) ; characterized in that The precast concrete upper column (1) is provided with an upper longitudinal main reinforcement (6), the precast concrete lower column (2) is provided with a lower longitudinal main reinforcement (7), the precast prestressed concrete composite beam (3) is provided with a precast prestressed concrete beam (8) and a beam composite layer (9), the precast prestressed concrete beam (8) is provided with prestressed reinforcement (10) and ordinary reinforcement (11), and the beam composite layer (9) is provided with a top-through steel bar (12), and the composite slab (5) is composed of a precast concrete slab (13) and a slab composite layer (14) cast on the slab; The upper longitudinal main reinforcement (6) extends out of the bottom surface of the precast upper column (1) and is directly anchored in the UHPC joint core area (4), the lower longitudinal main reinforcement (7) extends out of the top surface of the precast lower column (2) and is directly anchored in the UHPC joint core area (4), and the prestressed reinforcement (10) and the ordinary reinforcement (11) extend out of the end surface of the precast prestressed concrete beam (8) and are directly anchored or bent and anchored in the UHPC joint core area (4) ; The precast prestressed concrete composite beam (3) can also be a full precast prestressed concrete beam; the prestressed reinforcement (10) comprises pre-tensioned straight or folded line prestressed reinforcement and post-tensioned bonded, unbonded or slow-bonded straight, folded or curved line prestressed reinforcement; The precast prestressed concrete composite beam (3) is calculated as a prestressed concrete simply supported beam before casting the beam composite layer (9), the slab composite layer (14) and the UHPC joint core area (4), and is calculated as a frame beam after casting the UHPC joint core area (4), the beam composite layer (9) and the slab composite layer (14) ; for an unbonded prestressed beam, the effective prestress is used for calculation at the normal use limit state, and the stress increment of the unbonded reinforcement is considered at the ultimate bearing limit state; The edge joint, the middle joint and the corner joint core area of the precast prestressed concrete frame structure system are all UHPC joint core areas (4) ; The stirrups in the UHPC joint core area (4) are arranged according to design requirements, and the shear bearing capacity of the core area is calculated by considering that the steel fibers in the UHPC are equivalent to horizontal stirrups and vertical longitudinal reinforcement and considering their contribution to the shear resistance of the joint core area; The construction method of the precast prestressed concrete frame structure system comprises the following steps: The end of the precast prestressed concrete beam (8) is placed on the precast concrete lower column (2), the precast concrete upper column (1) is hoisted to directly above the precast concrete lower column (2), and the area enclosed by the precast prestressed concrete beam and the precast concrete lower column and the upper column is the UHPC joint core area.

2. The UHPC connected precast prestressed concrete frame structural system of claim 1, wherein, The precast prestressed concrete composite beam (3) is composed of the precast prestressed concrete beam (8) and the beam composite layer (9), and the composite slab (5) is composed of the precast concrete slab (13) and the slab composite layer (14) cast on the slab.

3. The UHPC connected precast prestressed concrete frame structural system of claim 1, wherein, 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 prefabricated prestressed concrete composite beam (3) are provided with recessed grooves.

4. The UHPC connected precast prestressed concrete frame structural system of claim 1, wherein, The stirrups in the prefabricated concrete upper column (1), the prefabricated concrete lower column (2), and the prefabricated prestressed concrete composite beam (3) are divided into dense areas and non-dense areas.

5. The UHPC connected precast prestressed concrete frame structural system of claim 1, wherein, The top surface of the prefabricated prestressed concrete beam (8) and the prefabricated concrete slab (13) is provided with a rough surface layer.

6. The construction method of the UHPC connected precast prestressed concrete frame structural system according to any one of claims 1 to 5, characterized in that, The method comprises the following steps: Step 1: prefabricated concrete lower column (2), prefabricated concrete upper column (1), prefabricated prestressed concrete beam (8), prefabricated concrete slab (13) are made; wherein the prefabricated concrete lower column (2), the prefabricated concrete upper column (1) extends the longitudinal reinforcement and anchors into the node core area, and sufficient anchoring length is reserved; the prefabricated prestressed concrete beam (8) extends the ordinary steel bars and the prestressed reinforcement and anchors into the node core area, and sufficient anchoring length is reserved; wherein, when the prefabricated prestressed concrete beam (8) is made, the prestressed reinforcement (10) is a pre-tensioned prestressed reinforcement, the prestressed reinforcement (10) is pre-tensioned on the pedestal, and then the concrete is poured, the prestressed reinforcement (10) is released when the concrete reaches sufficient strength, and sufficient anchoring length is reserved at the end of the prefabricated beam; the prestressed reinforcement (10) is a post-tensioned prestressed reinforcement, the post-tensioned prestressed reinforcement is pre-buried at the designed position (a corrugated pipe needs to be pre-buried for bonding), and sufficient length is reserved at both ends, and then the concrete is poured, and the post-tensioned prestressed reinforcement is tensioned when the concrete reaches the designed tensioning strength (grouting is needed for bonding); Step 2: after the prefabricated components are completed, the prefabricated concrete lower column (2) is hoisted and installed on the foundation, and then a proper number of stirrups are installed on the extended longitudinal reinforcement (7); Step 3: the prefabricated prestressed concrete beam (8) is hoisted to the top surface of the prefabricated concrete lower column (2), the bottom surface of the prefabricated prestressed concrete beam (8) is flush with the top surface of the prefabricated concrete lower column (2), the end of the prefabricated prestressed concrete beam (8) is placed on the prefabricated concrete lower column (2), and is fixed with simple supports, and the support can be omitted due to the prestressed action in the beam; wherein the steel bars (11) extending from the two prefabricated prestressed concrete beams (8) are reasonably avoided in the node core area and are directly anchored, and the prestressed reinforcement (10) extending from the two prefabricated prestressed concrete beams (8) is reasonably avoided in the node core area and is anchored in a straight line or a bent line; 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 supports (15), and the stirrups installed in step 2 are well tied; wherein the steel bars extending from the prefabricated concrete upper and lower columns are reasonably avoided in the node core area and are directly anchored; Step 5: the top longitudinal steel bars (12) are passed through the stirrups reserved in the composite layer and the node core area (4) and are well tied, and then the UHPC node core area (4) is poured, and the formwork is arranged so that the UHPC does not enter the beam composite layer (9) part; Step 6: the prefabricated concrete flat slab, composite slab, double T slab or secondary beam is hoisted to the prefabricated prestressed concrete beam (8) and is fixed. Step 7: pouring the beam superimposed layer (9) and the plate superimposed layer (14); Step 8: repeating the above manufacturing process to complete the prefabricated prestressed concrete frame structure system.

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