A uhcp connected post-tensioned bonded co-tensioned prefabricated prestressed concrete frame structure system and its design and construction method

Abstract

The application discloses a UHPC connected post-tensioned bonded co-tensioned prefabricated prestressed concrete frame structure system, which comprises a prefabricated concrete upper column, a prefabricated concrete lower column, a post-tensioned bonded co-tensioned prefabricated prestressed concrete composite beam, a UHPC node core area and a composite slab. The upper longitudinal main reinforcement, the lower longitudinal main reinforcement, the common steel bars and the pre-tensioned prestressed reinforcement are directly anchored or bent and anchored in the UHPC node core area. The structure system not only is convenient and fast in on-site construction, improves the component installation efficiency, but also can greatly reduce the anchoring length of the steel bars, greatly reduce the amount of the 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, thereby improving the seismic performance of the overall frame structure. The use of the pre-tensioned prestressed reinforcement can realize less support or free support in the prefabricated beam construction, the secondary post-tensioning bonding can improve the bearing capacity of the beam and enhance the overall performance of the structure.

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 bonded co-tension prefabricated prestressed concrete frame structure system 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 because of its fast construction speed, factory production of components, reduction of on-site wet work and reduction of environmental pollution. After years of development and promotion, prefabricated assembly type concrete structure has been widely researched and used.

[0003] Prefabricated assembly type concrete frame structure refers to the structure that beam-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 structure, 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, etc., 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] Post-tensioned bonded co-tension prestressed assembly type concrete structure is a structure formed by assembling prefabricated ordinary concrete components and prefabricated pretensioned prestressed components together to work together through tensioning of prestressed reinforcement, which has the characteristics of pretensioned prestressed, post-tensioned bonded 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 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, and 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, combined with the excellent performance of UHPC, a UHPC connected post-tensioned bonded co-tension prefabricated prestressed concrete framework structure system and its design and construction method are proposed. It combines three traditional structures: pre-tensioned prestressed structure, post-tensioned bonded prestressed structure and assembled structure and composite structure, and uses UHPC high-performance material, so as to improve the seismic performance of prefabricated assembled concrete framework structure.

[0007] The advantages of the present application mainly lie in the connection technology of prefabricated pre-tensioned prestressed 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 conducive to realizing the seismic fortification requirements of strong joints and weak components, thereby improving the ductility of beam-column joints and improving 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 bonded co-tension prefabricated prestressed concrete 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 bonded co-tension prefabricated prestressed concrete framework structure system, comprising a prefabricated concrete upper column, a prefabricated concrete lower column, a post-tensioned bonded co-tension 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 post-tensioned bonded co-tension prefabricated prestressed concrete composite beam is provided with a prefabricated pre-tensioned prestressed concrete beam, a beam composite layer and a post-tensioned bonded prestressed reinforcement, the prefabricated pre-tensioned prestressed concrete beam is provided with ordinary steel bars and pre-tensioned prestressed reinforcement, the beam composite layer is provided with top longitudinal steel bars, and 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 ordinary steel and the pre-tensioned prestressed reinforcement extends out of the end surface of the prefabricated pre-tensioned prestressed concrete beam and is directly anchored in the UHPC node core area;

[0012] The pre-tensioned prestressed reinforcement includes straight or broken line shaped reinforcement, and the post-tensioned bonded prestressed reinforcement includes straight, broken line, or curved shaped reinforcement.

[0013] The post-tensioned bonded shared-tension prefabricated prestressed concrete composite beam can also be a full prefabricated prestressed beam.

[0014] The post-tensioned bonded prestressed reinforcement in the node core area can be bonded, partially bonded, unbonded, or non-bonded.

[0015] The post-tensioned bonded shared-tension prefabricated prestressed concrete composite beam is constructed according to the pre-tensioned prestressed concrete simply supported beam before pouring the beam composite layer, the plate composite layer, and the UHPC node core area, after pouring the node core area and the beam composite layer and the plate composite layer, when the strength of the node and the composite layer concrete reaches the design requirement, the post-tensioned bonded prestressed reinforcement is tensioned, and after the tensioning is completed, the construction stage calculation is performed according to the frame beam; after the post-tensioned bonded prestressed reinforcement is established, the construction calculation is performed according to the effective prestress, for the partially bonded and non-bonded, non-bonded in the node core area, the effective prestress is calculated in the normal use limit state, and the stress increment of the non-bonded reinforcement is considered in the ultimate bearing limit state; under the seismic load, the restoring performance provided by the non-bonded reinforcement is considered.

[0016] Further, the post-tensioned bonded shared-tension prefabricated prestressed concrete composite beam is composed of a prefabricated pre-tensioned prestressed concrete beam, a beam composite layer, and a post-tensioned bonded prestressed reinforcement.

[0017] Further, the post-tensioned bonded prestressed reinforcement is arranged in a corrugated pipe pre-buried in the prefabricated pre-tensioned prestressed concrete beam component, passes through the corrugated pipes pre-buried in the beam composite layer and 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.

[0018] 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 bonded shared-tension prefabricated prestressed concrete composite beam are all provided with recessed grooves (U-shaped grooves can also be arranged at the beam ends, and constructional shear reinforcement can be arranged as necessary).

[0019] Further, the prefabricated concrete upper column is fixed at the corresponding position by a reliable support.

[0020] Further, the stirrups in the precast concrete upper column, the precast concrete lower column and the post-tensioned and co-tensioned precast prestressed concrete composite beam are divided into the encryption area and the non-encryption area, the stirrups in the UHPC node core area are arranged according to the design requirement, the shear bearing capacity of the core area is calculated according to the inclined strut model, and the steel fibers in the UHPC are equivalent to the horizontal stirrup and the vertical longitudinal reinforcement, the contribution of the steel fibers to the shear resistance of the node core area is considered, and the beneficial contribution of the bonded prestressed tendon to the shear resistance of the node is considered.

[0021] Further, the top surface of the precast pre-tensioned prestressed concrete beam and the precast concrete slab is provided with a rough surface layer.

[0022] The application also provides a design method of the system, comprising the following steps:

[0023] Step 1: the beam and the column are designed according to the existing specification and the invention patent;

[0024] 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 calculated jh :

[0025] The shear bearing capacity of the frame beam-column node should meet the following provisions:

[0026]

[0027] V jh =υ jh ·b j ·h c +V fh +0.4N pe

[0028] υ jh =α1·α2·f c

[0029] α1=0.34-0.00018·k s

[0030] α2=0.00018f c 2 -0.03f c +1.7

[0031] for middle node

[0032] k s =500, for edge node

[0033] V fh =ηλ f h b b c

[0034]

[0035] In the formula: A sjh —Core area of the node hoop;

[0036] f yj —Design value of the core area of the node hoop yield strength;

[0037] b j —Effective width of the node;

[0038] h c —Column height;

[0039] e—Beam column eccentricity;

[0040] N pe —Effective prestress force of post-tensioned prestressed reinforcement acting on the core area of the node;

[0041] b c —Column width;

[0042] f c —Design value of the axial compressive strength of concrete;

[0043] η—Effective coefficient of UHPC steel fiber;

[0044] l—UHPC steel fiber length;

[0045] d—UHPC steel fiber diameter;

[0046] V f —UHPC steel fiber volume content;

[0047] Step 3: In the intermediate node of the intermediate layer of the frame, the upper longitudinal reinforcement of the frame beam should penetrate the intermediate node; the diameter of each beam longitudinal reinforcement penetrating the middle column should not be greater than the smaller value of 1 / 18 and x of the column sectional size in that direction for seismic grades of one, two and three; x is calculated according to the following formula:

[0048]

[0049] In the formula: —Design axial compression ratio;

[0050] A s,top —Beam top longitudinal reinforcement area, if the left and right beam bottom longitudinal reinforcement areas are not equal, take the average value;

[0051] A s —Beam top and bottom longitudinal reinforcement area.

[0052] A UHPC connected post-tensioned bonded shared-tension prefabricated prestressed concrete frame structure system, comprising the following steps:

[0053] Step 1: prefabricated concrete lower column, prefabricated concrete upper column, prefabricated pre-tensioned prestressed concrete beam, prefabricated concrete slab are made; wherein the prefabricated concrete lower column and the prefabricated concrete upper column are anchored into the node core area with sufficient anchoring length; when prefabricating the pre-tensioned prestressed concrete beam, the pre-tensioned prestressed steel bars are tensioned on the pedestal, the corrugated pipes required for the bonded prestressed steel bars are pre-buried in the beam according to the design position, and sufficient length is reserved on both sides, then the concrete is poured, and when the concrete is cured to sufficient strength, the pre-tensioned prestressed steel bars are released and sufficient anchoring length is reserved at the beam end;

[0054] Step 2: after the prefabricated components are cured, the prefabricated concrete lower column is hoisted and installed on the foundation, then a proper number of stirrups are installed on the extended longitudinal main reinforcement;

[0055] Step 3: the prefabricated pre-tensioned prestressed concrete beam is hoisted to the top surface of the prefabricated concrete lower column, the bottom surface of the prefabricated pre-tensioned prestressed concrete beam is flush with the top surface of the prefabricated concrete lower column, the end of the prefabricated pre-tensioned prestressed concrete beam is placed on the prefabricated concrete lower column and fixed with support, and since the beam has the pre-tensioned prestressed effect, support can be omitted; wherein the ordinary steel bars and pre-tensioned prestressed steel bars on both sides of the pre-tensioned prestressed concrete beam are reasonably avoided and directly anchored or bent and anchored in the node core area according to the construction requirements;

[0056] Step 4: the prefabricated concrete upper column is hoisted to directly above the prefabricated concrete lower column, and the prefabricated concrete upper column is fixed 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 of the prefabricated concrete upper and lower columns is reasonably avoided and directly anchored in the node core area;

[0057] Step 5: the top longitudinal steel bars are passed through the stirrups reserved in the beam composite layer area and the node core area and tied, and a section of corrugated pipe is pre-buried in the node core area to form a whole with the corrugated pipe pre-buried in the pre-tensioned prestressed concrete beam, then the UHPC node core area is poured, and the formwork is set to prevent the UHPC from entering the beam composite layer part;

[0058] Step 6: after the UHPC node core area is cured to sufficient strength, the prefabricated concrete flat slab, composite slab, double-T slab or secondary beam is hoisted to the prefabricated prestressed concrete beam and fixed;

[0059] Step 7: pouring the beam composite layer and the slab composite layer;

[0060] Step 8: After the beam and slab composite layer concrete is cured to sufficient strength, the reinforcement is passed in the corrugated pipe and the prestressed reinforcement is tensioned, the corrugated pipe in the bonding part of the beam and joint is grouted, and the part without bonding prestressed reinforcement of the joint is not grouted;

[0061] Step 9: Repeat the above manufacturing process, and complete the post-tensioned bonded co-tensioned prefabricated prestressed concrete frame structure system.

[0062] Compared with the prior art, the advantages of the present application are that:

[0063] 1. The present application combines prefabricated assembly type concrete structure, pretensioned prestressed structure and post-tensioned bonded co-tensioned prestressed structure together, and uses the advantages of prefabricated assembly type structure, such as convenient and fast construction, good construction quality, energy saving and environmental protection, and combines the advantages of post-tensioned bonded co-tensioned prestressed structure, such as improved structural performance, reduced cross-sectional height of components, reduced self weight, improved component crack resistance and self-recovery, so as to improve the seismic performance of the overall frame structure. The use of pretensioned prestressed reinforcement can realize less support or free support during the prefabricated beam construction, and the secondary post-tensioned bonding can improve the bearing capacity of the beam and enhance the overall performance of the structure.

[0064] 2. The present application uses UHPC material with excellent performance, which is applied in the joint core area, so as to realize reliable connection of the prefabricated beam and column components, improve the bearing capacity and seismic performance of the joint, greatly reduce the anchoring length of the steel reinforcement and steel strand, and significantly reduce the amount of hoop reinforcement in the joint core area, thereby avoiding the congestion of steel reinforcement in the joint core area, and greatly improving the production, transportation and installation efficiency of the prefabricated beam and column components. BRIEF DESCRIPTION OF DRAWINGS

[0065] Figure 1 It is a structural schematic diagram of the prefabricated prestressed concrete frame structure system based on UHPC of the present application

[0066] Figure 2 It is a reinforcement schematic diagram of a two-span frame structure of the present application

[0067] Figure 3 It is a material schematic diagram of a two-span frame structure of the present application

[0068] Figure 4 It is a detailed drawing of the edge joint of the intermediate layer frame of the present application

[0069] Figure 5 It is an axonometric view of the edge joint of the intermediate layer frame of the present application

[0070] Figure 6 It is a detailed drawing of the middle joint of the intermediate layer frame of the present application

[0071] Figure 7 It is an axonometric view of the middle joint of the intermediate layer frame of the present application DETAILED DESCRIPTION

[0072] In order to make the features, objectives and advantages of the present application more easily understood, the following further describes the present application with reference to the accompanying drawings and specific embodiments.

[0073] As shown in Figures 1-7 The UHPC connected post-tensioned bonded shared-tension prefabricated prestressed concrete frame structure system comprises a prefabricated concrete upper column (1), a prefabricated concrete lower column (2), a post-tensioned bonded shared-tension prefabricated prestressed concrete composite beam (3), a UHPC node core area (4), and a composite slab (18).

[0074] 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-tensioned bonded shared-tension prefabricated prestressed concrete composite beam (3) is provided with a prefabricated pre-tensioned prestressed concrete beam (7) and a beam composite layer (8) and a post-tensioned bonded prestressed reinforcement (9), the prefabricated pre-tensioned prestressed concrete beam (7) is provided with ordinary reinforcement (10) and pre-tensioned prestressed reinforcement (17), the beam composite layer (8) is provided with top longitudinal reinforcement (11), and the composite slab (18) is composed of a prefabricated concrete slab (19) and a slab composite layer (20) poured on the slab.

[0075] 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) and the pre-tensioned prestressed reinforcement (17) extend out of the end surface of the prefabricated pre-tensioned prestressed concrete beam (7) and are directly anchored in the UHPC node core area (4).

[0076] The pre-tensioned prestressed reinforcement (17) comprises straight or folded line reinforcement, and the post-tensioned bonded prestressed reinforcement (9) comprises straight, folded, or curved line reinforcement.

[0077] The post-tensioned bonded shared-tension prefabricated prestressed concrete composite beam (3) can also be a full prefabricated prestressed beam.

[0078] The post-tensioned bonded prestressed reinforcement (9) in the node core area can be bonded, partially bonded, unbonded, or unbonded.

[0079] The post-tensioned bonded co-tensioned prefabricated prestressed concrete composite beam (3) is calculated according to the construction of the simply supported pre-tensioned concrete beam before pouring the beam composite layer (8), the plate composite layer (20) and the UHPC node core area (4), and after pouring the node core area (4) and the beam composite layer (8) and the plate composite layer (20), the node and the composite layer concrete strength reaches the design requirement, the post-tensioned bonded prestressed tendon (9) is tensioned, and after the tensioning is completed, the construction stage calculation is carried out according to the frame beam; the post-tensioned bonded prestressed tendon (9) is calculated by effective prestress after the establishment of the prestress, and the bonded and unbonded prestressed tendons in the node core area are calculated by effective prestress in the normal use limit state, and the stress increment of the unbonded tendon is considered in the ultimate bearing limit state; under the earthquake load, the restoring performance provided by the unbonded tendon is considered.

[0080] The post-tensioned bonded co-tensioned prefabricated prestressed concrete composite beam (3) is composed of a prefabricated pre-tensioned concrete beam (7), a beam composite layer (8) and a post-tensioned bonded prestressed tendon (9); and the composite plate (18) is composed of a prefabricated concrete plate (19) and a plate composite layer (20) poured on the plate.

[0081] The post-tensioned bonded prestressed tendon (9) is arranged in the corrugated pipe pre-buried in the prefabricated pre-tensioned concrete beam (7) component, passes through the corrugated pipe pre-buried in the beam composite layer (8) and 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 anchors (16).

[0082] 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 bonded co-tensioned prefabricated prestressed concrete composite beam (3) are all provided with recesses (U-shaped grooves can also be arranged at the beam ends, and constructional shear reinforcement can be arranged if necessary).

[0083] The prefabricated concrete upper column (1) is fixed in the corresponding position by reliable support (12).

[0084] The stirrups (13) in the prefabricated concrete upper column (1), the prefabricated concrete lower column (2) and the post-tensioned bonded co-tensioned prefabricated prestressed concrete 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 bearing capacity of the core area is calculated according to the inclined strut model, 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 bonded prestressed tendon to the shear resistance of the node is also considered.

[0085] The top surface of the prefabricated pre-tensioned prestressed concrete beam (7) and the prefabricated concrete slab (19) is provided with a smooth surface layer.

[0086] The anti-seismic design of the system comprises the following steps:

[0087] Step 1: The beam and column are designed according to the existing specification and invention patent;

[0088] Step 2: The anti-seismic design of the node needs to be carried out according to the following method: calculating the horizontal shear capacity V of the node jh ;

[0089] Step 3: The diameter of the longitudinal steel bars of each beam penetrating the middle column should not be greater than 1 / 18 of the smaller value of x and the sectional size of the column in that direction.

[0090] A UHPC connected post-tensioned bonded co-tensioned prefabricated prestressed concrete frame structure system, characterized in that it comprises the following steps:

[0091] Step 1: prefabricated concrete lower column (2), prefabricated concrete upper column (1), prefabricated pre-tensioned prestressed concrete beam (7), prefabricated concrete slab (19) are made; wherein the prefabricated concrete lower column (2) and the prefabricated concrete upper column (1) are anchored into the node core area (4) with sufficient anchoring length; when making the pre-tensioned prestressed concrete beam (7), the pre-tensioned prestressed steel bars (17) are pre-tensioned on the pedestal, the corrugated pipes required for the bonded prestressed steel bars (9) are pre-buried in the beam according to the design position, and sufficient length is reserved on both sides, then the concrete is poured, and when the concrete is cured to sufficient strength, the pre-tensioned prestressed steel bars (17) are released and sufficient anchoring length is reserved at the end of the beam;

[0092] Step 2: After the prefabricated components are cured, the prefabricated concrete lower column (2) is hoisted and installed on the foundation, and then a proper number of stirrups (14) are installed on the extended longitudinal main reinforcement (6);

[0093] Step 3: The prefabricated pre-tensioned prestressed concrete beam (7) is hoisted to the top surface of the prefabricated concrete lower column (2), the bottom surface of the prefabricated pre-tensioned prestressed concrete beam (7) is flush with the top surface of the prefabricated concrete lower column (2), the end of the prefabricated pre-tensioned prestressed concrete beam (7) is placed on the prefabricated concrete lower column (2), and is fixed with support, and since the beam has pre-tensioned prestressed effect, support can be omitted; wherein the ordinary steel bars (10) and the pre-tensioned prestressed steel bars (17) on both sides of the pre-tensioned prestressed concrete beam (7) are reasonably avoided according to the construction requirements in the node core area and are directly anchored or bent and anchored;

[0094] 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 (12), at this time, tie the stirrup (14) installed in step 2 and the column longitudinal reinforcement together; wherein the longitudinal reinforcement of the prefabricated concrete upper and lower columns is reasonably avoided in the node core area and directly anchored;

[0095] Step 5: pass the top longitudinal reinforcement (11) through the stirrup (13) reserved in the beam composite layer area and the node core area (4) and tie it well, and embed a section of corrugated pipe in the node core area to form a whole with the corrugated pipe embedded in the pre-tensioned prestressed concrete beam (7), then pour the UHPC node core area (4), and set the formwork so that the UHPC does not enter the beam composite layer (8) part;

[0096] Step 6: after the UHPC node core area (4) is cured to sufficient strength, hoist the prefabricated concrete slab, composite slab, double-T slab or secondary beam to the prefabricated prestressed concrete beam (7) and fix it;

[0097] Step 7: pour the beam composite layer (8) and the slab composite layer (20);

[0098] Step 8: after the beam composite layer (8) and the slab composite layer (20) are cured to sufficient strength, pass the reinforcement in the corrugated pipe and tension the prestressed reinforcement (9), grout in the corrugated pipe of the beam and the node with the bonded part, and do not grout for the node unbonded prestressed reinforcement part;

[0099] Step 9: repeat the above manufacturing process to complete the post-tensioned bonded and co-tensioned prefabricated prestressed concrete frame structure system.

[0100] 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 limiting, and the present application can be easily improved, changed or replaced without departing from the method concept and technical solution of the present application. These improvements and changes are within the scope of protection of the present application.

Claims

1. A UHPC connected post-tensioned bonded shared-tension precast prestressed concrete frame structure system, comprising a precast concrete upper column (1), a precast concrete lower column (2), a post-tensioned bonded shared-tension precast prestressed concrete composite beam (3), a UHPC node core area (4) and a composite slab (18) ; characterized in that The precast concrete upper column (1) is provided with an upper longitudinal main reinforcement (5), the precast concrete lower column (2) is provided with a lower longitudinal main reinforcement (6), the post-tensioned bonded shared-tension precast prestressed concrete composite beam (3) is provided with a precast pre-tensioned prestressed concrete beam (7), a beam composite layer (8) and a post-tensioned bonded prestressed reinforcement (9), the precast pre-tensioned prestressed concrete beam (7) is provided with ordinary reinforcement (10) and pre-tensioned prestressed reinforcement (17), the beam composite layer (8) is provided with a top full-length reinforcement (11), and the composite slab (18) is composed of a precast concrete slab (19) and a 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 UHPC node core area (4), the lower longitudinal main reinforcement (6) extends out of the top surface of the precast lower column (2) and is directly anchored in the UHPC node core area (4), and the ordinary reinforcement (10) and the pre-tensioned prestressed reinforcement (17) extend out of the end surface of the precast pre-tensioned prestressed concrete beam (7) and are directly anchored in the UHPC node core area (4) ; Characterized in that the pre-tensioned prestressed reinforcement (17) comprises a straight line or a broken line, and the post-tensioned bonded prestressed reinforcement (9) comprises a straight line, a broken line or a curved line; The post-tensioned bonded shared-tension precast prestressed concrete composite beam (3) can also be a full precast prestressed beam; The post-tensioned bonded prestressed reinforcement (9) can be bonded, partially bonded, unbonded or non-bonded in the node core area; The post-tensioned bonded shared-tension precast prestressed concrete composite beam (3) is calculated according to the pre-tensioned prestressed concrete simply supported beam before pouring the beam composite layer (8), the slab composite layer (20) and the UHPC node core area (4), and after pouring the node core area (4), the beam composite layer (8) and the slab composite layer (20), the node and the composite layer concrete strength reaches the design requirement, the post-tensioned bonded prestressed reinforcement (9) is tensioned, and after the tensioning is completed, the construction stage calculation is carried out according to the frame beam; After the pre-stress is established, the post-tensioned bonded prestressed reinforcement (9) is calculated according to the effective pre-stress in the construction calculation, and for the partially bonded and unbonded or non-bonded in the node core area, the effective pre-stress is calculated in the normal use limit state, the stress increment of the unbonded reinforcement is considered in the ultimate bearing limit state, and the restoring performance provided by the unbonded reinforcement is considered under the seismic load; The post-tensioned bonded prestressed reinforcement (9) is arranged in the corrugated pipe pre-buried in the precast pre-tensioned prestressed concrete beam (7) component, passes through the corrugated pipe pre-buried in the beam composite layer (8) and the UHPC node core area (4) and extends out of the UHPC node core area (4), and clamps (15) and anchors (16) are respectively arranged at both ends of the post-tensioned bonded prestressed reinforcement (9). The edge joint, the middle joint and the corner joint core area of the co-tension prefabricated prestressed concrete frame structure system are UHPC joint core areas (4); The stirrups in the UHPC joint core area (4) are arranged according to design requirements, and the calculation of the shear bearing capacity of the core area considers that the steel fibers in the UHPC are equivalent to horizontal stirrups and vertical longitudinal reinforcement, and considers the contribution of the steel fibers to the shear resistance of the joint core area; The construction method of the co-tension prefabricated prestressed concrete frame structure system comprises: The end of the prefabricated pretension prestressed concrete beam (7) is placed on the prefabricated concrete lower column (2), the prefabricated concrete upper column (1) is hoisted to directly above the prefabricated concrete lower column (2), and the area enclosed between the prefabricated pretension prestressed concrete beam and the prefabricated concrete lower column and upper column is a UHPC joint core area.

2. The UHPC connected post-tensioned bonded co-tensioned precast prestressed concrete frame structure system according to claim 1, characterized in that, The post-tensioned bonded co-tension prefabricated prestressed concrete composite beam (3) is composed of a prefabricated pretension prestressed concrete beam (7), a beam composite layer (8) and post-tensioned bonded prestressed reinforcement (9); and the composite slab (18) is composed of a prefabricated concrete slab (19) and a slab composite layer (20) poured on the slab.

3. The UHPC connected post-tensioned bonded co-tensioned precast prestressed concrete frame structural system according to claim 1, characterized in that, 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 bonded co-tension prefabricated prestressed concrete composite beam (3) are provided with recessed grooves or U-shaped grooves.

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

5. The UHPC connected post-tensioned bonded co-tensioned precast prestressed concrete frame structural system according to claim 1, wherein, The top surface of the prefabricated pretension prestressed concrete beam (7) and the prefabricated concrete slab (19) is provided with a rough surface layer.

6. The construction method of the UHPC connected post-tensioned bonded and co-tensioned 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: prefabricate a prefabricated concrete lower column (2), a prefabricated concrete upper column (1), a prefabricated pretension prestressed concrete beam (7) and a prefabricated concrete slab (19); wherein the prefabricated concrete lower column (2) and the prefabricated concrete upper column (1) extend the longitudinal reinforcement to be anchored into the joint core area (4) and require sufficient anchoring length to be reserved; when the prefabricated prestressed concrete beam (7) is being prefabricated, the pretension prestressed reinforcement (17) is tensioned on the pedestal, the corrugated pipe required for the bonded prestressed reinforcement (9) is pre-buried in the beam according to the design position, and sufficient length is reserved on both sides, then the concrete is poured, and when the concrete is cured to sufficient strength, the pretension prestressed reinforcement (17) is released and sufficient anchoring length is reserved at the end of the beam; Step 2: after the prefabricated components are cured, hoist the prefabricated concrete lower column (2) and install it on the foundation, then install a proper number of stirrups on the extended longitudinal reinforcement (6); Step 3: Hoist the prefabricated pre-tensioned prestressed concrete beam (7) to the top surface of the prefabricated concrete lower column (2), make the bottom surface of the prefabricated pre-tensioned prestressed concrete beam (7) flush with the top surface of the prefabricated concrete lower column (2), make the end of the prefabricated pre-tensioned prestressed concrete beam (7) rest on the prefabricated concrete lower column (2), and fix it with support, and since the beam has been pre-tensioned with prestressing force, it can also be free of support; wherein the ordinary steel bars (10) and pre-tensioned prestressed bars (17) extending from the pre-tensioned prestressed concrete beams (7) on both sides are reasonably avoided and directly anchored or bent and anchored in the node core area according to the construction requirements; Step 4: Hoist the prefabricated concrete upper column (1) directly above the prefabricated concrete lower column (2), and fix the prefabricated concrete upper column (1) in the corresponding position with reliable support (12), at this time, the stirrups and column longitudinal bars installed in step 2 are tied together; wherein the longitudinal bars extending from the prefabricated concrete upper and lower columns are reasonably avoided and directly anchored in the node core area; Step 5: Pass the top longitudinal steel bars (11) through the stirrups reserved in the beam composite layer area and the node core area (4) and tie them well, and embed a section of corrugated pipe in the node core area to form a whole with the corrugated pipe embedded in the pre-tensioned prestressed concrete beam (7), then pour the UHPC node core area (4), and set the formwork so that the UHPC does not enter the beam composite layer (8) part; Step 6: After the UHPC node core area (4) is cured to sufficient strength, hoist the prefabricated concrete slab, composite slab, double T slab or secondary beam to the prefabricated prestressed concrete beam (7) and fix it; Step 7: Pour the beam composite layer (8) and the slab composite layer (20); Step 8: After the beam composite layer (8) and the slab composite layer (20) are cured to sufficient strength, pass the bars in the corrugated pipe and tension the prestressed bars (9), and grout the corrugated pipe in the bonded part of the beam and node, and do not grout the unbonded prestressed bar part of the node; Step 9: Repeat the above manufacturing process to complete the post-tensioned bonded and co-tensioned prefabricated prestressed concrete frame structure system.

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