A double post-tensioning prefabricated prestressed concrete open-hole beam frame structure system connected by UHPC and a design and construction method thereof

Abstract

The application discloses a UHPC connected double post-tensioning prefabricated prestressed concrete open-hole beam frame structure system, which comprises a prefabricated concrete upper column, a prefabricated concrete lower column, a double post-tensioning prefabricated prestressed concrete open-hole composite beam, a UHPC node core area and a composite slab. The upper longitudinal main reinforcement, the lower longitudinal main reinforcement, the common steel bar and the post-tensioning prestressed reinforcement are directly anchored in the UHPC node core area. The structure system is not only convenient and fast in on-site construction and 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 double post-tensioning design can be reasonably designed according to different span, different load, different seismic intensity and other requirements, reduces the cost and meets the use requirements.

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 double post-tensioning prefabricated prestressed concrete open-hole beam frame structure system and its design and construction method. 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 and column components are prefabricated in a prefabrication plant and transported to the construction site for connection to form an integral structure. Compared with cast-in-place concrete 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. It 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 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] Double post-tensioning assembly type concrete structure is a structure formed by assembling prefabricated ordinary concrete components and prefabricated post-tensioning components together and working together through tensioning of prestressed reinforcement, which has the characteristics of post-tensioning 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; 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 double post-tensioning prefabricated prestressed concrete open-hole beam framework structure system and its design and construction method are proposed. It combines three traditional structures of post-tensioning prestressed structure, prefabricated structure and composite structure, and uses UHPC high-performance materials, so as to improve the seismic performance of prefabricated concrete framework structure.

[0007] The advantages of the present application mainly lie in the connection technology of prefabricated post-tensioning prestressed concrete open-hole beam column components and the steel bar connection technology between components. In the aspect of component connection technology, the beam column components are connected by UHPC with excellent performance to form the UHPC joint core area, which is more conducive to the realization of the seismic fortification requirement of strong joint and weak component, thereby improving the ductility of beam column joint and further improving the seismic performance of the overall framework structure. In the aspect 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 double post-tensioning prefabricated prestressed concrete open-hole beam 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 using the following technical solutions:

[0009] A UHPC connected double post-tensioning prefabricated prestressed concrete open-hole beam framework structure system, comprising a prefabricated concrete upper column, a prefabricated concrete lower column, a double post-tensioning 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 double post-tensioning prefabricated prestressed concrete open-hole composite beam is provided with a prefabricated post-tensioning prestressed concrete open-hole beam, a beam composite layer and post-tensioning prestressed reinforcement two, the bottom of the prefabricated post-tensioning prestressed concrete open-hole beam is provided with ordinary steel bars and post-tensioning prestressed reinforcement one, and if necessary, a hanging reinforcement or a 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 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, and the ordinary steel bars and the post-tensioned prestressed bars extend out of the end surface of the prefabricated post-tensioned prestressed concrete opening beam and are directly anchored in the UHPC node core area;

[0012] The double post-tensioned prefabricated prestressed concrete opening composite beam can also be a full prefabricated prestressed concrete opening beam;

[0013] The post-tensioned prestressed bar one is only tensioned in the prefabricated post-tensioned prestressed concrete opening beam, and the post-tensioned prestressed bar two is tensioned together with the outside of the column in the prefabricated post-tensioned prestressed concrete opening beam;

[0014] The post-tensioned prestressed bar one and the post-tensioned prestressed bar two include straight-line, broken-line, and curved-line prestressed bars;

[0015] The post-tensioned prestressed bar one and the post-tensioned prestressed bar two are un-bonded, slow-bonded, or bonded prestressed bars;

[0016] When the post-tensioned prestressed bar one is calculated considering the self-weight and construction load in the construction stage, the effective prestress of the post-tensioned prestressed bar one is calculated; when the normal use or the ultimate bearing capacity is calculated, the post-tensioned prestressed bar one is calculated according to the actual bonding state of the prestressed bar, respectively according to the bonded and un-bonded;

[0017] The post-tensioned prestressed bar two in the node core area can be bonded, partially bonded, un-bonded, or un-bonded;

[0018] The double post-tensioned prefabricated prestressed concrete opening composite beam is calculated according to the post-tensioned prestressed concrete opening 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 prestressed bar two is tensioned, and after the tensioning is completed, the construction stage calculation is performed according to the un-bonded prestressed bar; the upper chord section at the opening of the prefabricated post-tensioned prestressed concrete opening beam is different before and after pouring the beam composite layer, the plate composite layer, and the UHPC node core area, and the stress state is also different, so the construction calculation of the upper and lower chord bars at the opening of the prefabricated post-tensioned prestressed concrete opening beam should be performed; when the normal use or the ultimate bearing capacity is calculated, the post-tensioned prestressed bar two is calculated according to the actual bonding state of the prestressed bar, respectively according to the bonded and un-bonded; for the un-bonded part of the post-tensioned prestressed bar two in the node core area, the restoring performance provided by the un-bonded part is considered under the seismic load.

[0019] Further, the double post-tensioning prefabricated prestressed concrete open-hole composite beam is composed of a prefabricated post-tensioning prestressed concrete open-hole beam, a beam composite layer and post-tensioning prestressed tendons two; the composite slab is composed of a prefabricated concrete slab and a slab composite layer poured on the slab.

[0020] Further, the post-tensioning prestressed tendons two are arranged in the prefabricated post-tensioning prestressed concrete open-hole beam component, pass through the UHPC node core area and extend out of the UHPC node core area at both ends, and are respectively fixed with clamps and anchors at both ends, one end being arranged outside the column and the other end being arranged in the beam composite layer.

[0021] 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 double post-tensioning prefabricated prestressed concrete open-hole composite beam are provided with recessed grooves.

[0022] Further, the prefabricated concrete upper column is fixed at the corresponding position by reliable support.

[0023] Further, the stirrups in the prefabricated concrete upper column, the prefabricated concrete lower column and the double post-tensioning prefabricated 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 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.

[0024] Further, the top surface of the prefabricated post-tensioning prestressed concrete open-hole beam and the prefabricated concrete slab is provided with a rough surface layer.

[0025] A UHPC connected double post-tensioning prefabricated prestressed concrete open-hole beam frame structure system, comprising the following steps:

[0026] Step 1: prefabricated concrete lower column, prefabricated concrete upper column, prefabricated post-tensioning prestressed concrete open-hole beam, prefabricated concrete slab are made; the strength of the upper and lower chords at the opening of the prefabricated post-tensioning prestressed concrete open-hole beam is calculated; wherein the prefabricated concrete lower column and the prefabricated concrete upper column need to reserve sufficient anchoring length for the anchoring of the longitudinal reinforcement into the node core area; when the post-tensioning prestressed concrete open-hole beam is made, the post-tensioning prestressed tendons one and the post-tensioning prestressed tendons two are pre-embedded in the beam at the designed position and sufficient length is reserved at both ends, and then the concrete is poured, the post-tensioning prestressed tendons one are tensioned when the concrete is cured to sufficient strength, and clamps and anchors are arranged at both ends; wherein when the post-tensioning prestressed tendons one and the post-tensioning prestressed tendons two are unbonded or slow-bonded prestressed tendons, they are directly pre-embedded at the designed position; when the post-tensioning prestressed tendons one (17) and the post-tensioning prestressed tendons two (9) are bonded prestressed tendons, corrugated pipes need to be pre-embedded in the prefabricated concrete beam;

[0027] Step 2: after the curing of the prefabricated component is completed, hoist the prefabricated concrete lower column and install it on the foundation, and then install a proper number of stirrups on the protruding longitudinal main reinforcement according to the design requirements;

[0028] Step 3: hoist the prefabricated post-tensioned prestressed concrete open-hole beam to the top surface of the prefabricated concrete lower column, make the bottom surface of the prefabricated post-tensioned prestressed concrete open-hole beam flush with the top surface of the prefabricated concrete lower column, make the end of the prefabricated post-tensioned prestressed concrete open-hole beam rest on the prefabricated concrete lower column, and fix it with a support, and since the beam has a prestressed action, the support can be omitted; wherein the ordinary steel reinforcement protruding from the two side post-tensioned prestressed concrete open-hole beams and the direct anchoring in the joint core area are reasonably avoided 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 bound together with the column longitudinal reinforcement; wherein the longitudinal reinforcement protruding from the prefabricated concrete upper and lower columns is reasonably avoided in the joint core area and direct anchoring is adopted;

[0030] Step 5: pass the top longitudinal reinforcement through the stirrups reserved in the beam composite layer area and the joint core area and bind them well, then bind the post-tensioned prestressed reinforcement two protruding from the post-tensioned prestressed concrete open-hole beam according to the design position in the joint core area, (when the post-tensioned prestressed reinforcement two is a bonded prestressed reinforcement, a section of corrugated pipe is pre-buried in the joint core area to form a whole with the corrugated pipe pre-buried in the post-tensioned prestressed concrete open-hole beam; when the post-tensioned prestressed reinforcement two is a non-bonded prestressed reinforcement, a sleeve pipe is needed to be sleeved on the non-bonded prestressed reinforcement in the joint core area), and then pour the UHPC joint core area, and set the formwork so that the UHPC does not enter the beam composite layer part;

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

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

[0033] Step 8: after the beam composite layer and the plate composite layer are cured to sufficient strength, tension the post-tensioned prestressed reinforcement two (when the post-tensioned prestressed reinforcement two is a bonded prestressed reinforcement, the reinforcement is first passed through the corrugated pipe and then tensioned, and finally grouting is carried out in the corrugated pipe of the bonded part of the beam and the joint, and no grouting is carried out for the non-bonded part of the joint) ;

[0034] Step 9: repeat the above manufacturing process to complete the double post-tensioned 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 concrete structure and post-tensioned prestressed structure together, and uses prefabricated structure which has the advantages of convenient and fast construction, good construction quality, energy saving and environmental protection, and combines post-tensioned prestressed structure to improve the structural performance, reduce the cross-section height of the component, reduce the self-weight, improve the crack resistance and self-recovery of the component, so as to improve the seismic performance of the overall frame structure. The double post-tensioning design can be reasonably designed according to different span, different load, different seismic intensity and other requirements, reduce the cost, and meet the use requirements.

[0037] 2.The present application uses UHPC material with excellent performance, which is applied in the node core area, can realize reliable connection of prefabricated beam column component, not only can improve the bearing capacity and seismic performance of the node, but also can greatly reduce the anchoring length of steel bars and steel strands, and can significantly reduce the amount of stirrups in the node core area, so as to avoid the congestion of steel bars in the node core area, and greatly improve the production, transportation and installation efficiency of prefabricated beam column component. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of the prefabricated prestressed concrete open beam frame structure system based on UHPC of the present application

[0039] Figure 2 It is a reinforcement schematic diagram of a two-span frame structure of the present application

[0040] Figure 3 It is a material schematic diagram of a two-span frame structure of the present application

[0041] Figure 4 It is a detailed drawing of the edge node of the intermediate layer frame of the present application

[0042] Figure 5 It is an axonometric view of the edge node of the intermediate layer frame of the present application

[0043] Figure 6 It is a detailed drawing of the middle node of the intermediate layer frame of the present application

[0044] Figure 7 It is an axonometric view of the middle node of the intermediate layer frame of the present application DETAILED DESCRIPTION

[0045] In order to make the features, objects and advantages of the present application more easily understood, the present application is further described below in combination with the drawings and specific embodiments.

[0046] As Figures 1-7As shown, the UHPC connected double post-tensioning prefabricated prestressed concrete open-hole beam frame structure system comprises a prefabricated concrete upper column (1), a prefabricated concrete lower column (2), a double post-tensioning prefabricated prestressed concrete open-hole composite beam (3), a UHPC node core area (4), and a composite slab (18);

[0047] The prefabricated concrete upper column (1) is provided with an upper longitudinal main reinforcement (5), the prefabricated concrete lower column (2) is provided with a lower longitudinal main reinforcement (6), the double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) is provided with a prefabricated post-tensioning prestressed concrete open-hole beam (7), a beam composite layer (8), and a post-tensioning prestressed tendon (9), the prefabricated post-tensioning prestressed concrete open-hole beam (7) is provided with ordinary reinforcement (10) and post-tensioning prestressed tendon (17) at the bottom, the beam composite layer (8) is provided with a top-through steel bar (11), and the composite slab (18) is composed of a prefabricated concrete slab (19) and a slab composite layer (20) 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) and the post-tensioning prestressed tendon (17) extend out of the end surface of the prefabricated post-tensioning prestressed concrete open-hole beam (7) and are directly anchored in the UHPC node core area (4);

[0049] The double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) can also be a full prefabricated prestressed concrete open-hole beam;

[0050] The post-tensioning prestressed tendon (17) is only tensioned in the prefabricated post-tensioning prestressed concrete open-hole beam (7), and the post-tensioning prestressed tendon (9) is tensioned together with the column outside in the prefabricated post-tensioning prestressed concrete open-hole beam (7);

[0051] The post-tensioning prestressed tendon (17) and the post-tensioning prestressed tendon (9) include straight, broken, and curved prestressed tendons;

[0052] The post-tensioning prestressed tendon (17) and the post-tensioning prestressed tendon (9) are unbonded, slow-bonded, or bonded prestressed tendons;

[0053] The post-tensioning prestressed tendon (17) is calculated for effective prestress when considering self-weight and construction load during the construction stage, and is calculated for actual bonding conditions of prestressed tendons when performing normal use or limit bearing calculation;

[0054] The post-tensioning prestressed tendon (9) can be bonded, partially bonded, unbonded, or non-bonded in the node core area;

[0055] The double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) is calculated according to the post-tensioning prestressed concrete open-hole simple beam before pouring the beam composite layer (8), the plate composite layer (20) and the UHPC node core area (4), and the post-tensioning prestressed tendon two (9) is tensioned after pouring the node core area (4) and the beam composite layer (8), the plate composite layer (20), when the node and the composite layer concrete strength reaches the design requirement, and the construction stage calculation is carried out according to the non-bonding prestressed tendon after tensioning is completed; the double post-tensioning prefabricated prestressed concrete open-hole composite beam is different in cross section at the hole opening before pouring the beam composite layer, the plate composite layer and the UHPC node core area and after pouring, and the stress state is also different, so the construction calculation should be carried out on the upper and lower chord bars at the hole opening of the prefabricated post-tensioning prestressed concrete open-hole beam; when the normal use or the ultimate bearing capacity is calculated, the post-tensioning prestressed tendon two (9) is calculated according to the actual bonding condition of the prestressed tendon respectively according to the bonding and non-bonding; for the non-bonding part of the post-tensioning prestressed tendon two (9) in the node core area, the restoring performance provided by it is considered under the earthquake load;

[0056] The double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) is composed of a prefabricated post-tensioning prestressed concrete open-hole beam (7), a beam composite layer (8) and a post-tensioning prestressed tendon two (9); the composite plate (18) is composed of a prefabricated concrete plate (19) and a plate composite layer (20) poured on the plate;

[0057] The post-tensioning prestressed tendon two (9) is arranged in the prefabricated post-tensioning prestressed concrete open-hole beam (7) component, passes through the UHPC node core area (4) and extends out of the UHPC node core area (4) at both ends, and clamps (15) and anchors (16) are respectively arranged at both ends, one end is arranged outside the column, and the other end is arranged in the beam composite layer;

[0058] 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 double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) are provided with recesses;

[0059] The prefabricated concrete upper column (1) is fixed in the corresponding position by reliable support (12);

[0060] The stirrups (13) in the prefabricated concrete upper column (1), the prefabricated concrete lower column (2) and the double post-tensioning 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 of the core area is calculated according to the softened tension-compression strut 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 capacity of the node core area is considered;

[0061] The top surface of the prefabricated post-tensioned prestressed concrete open-hole beam (7) and the prefabricated concrete slab (19) is provided with a smooth surface layer.

[0062] A UHPC connected double post-tensioned prefabricated prestressed concrete open-hole beam frame structure system, characterized by comprising the following steps:

[0063] Step 1: Make prefabricated concrete lower column (2), prefabricated concrete upper column (1), prefabricated post-tensioned prestressed concrete open-hole beam (7), prefabricated concrete slab (19); wherein the prefabricated concrete lower column (2), the prefabricated concrete upper column (1) extends the longitudinal reinforcement and anchors into the node core area (4) and needs to reserve enough anchoring length; check the strength of the upper and lower chord of the prefabricated post-tensioned prestressed concrete open-hole beam; when making the post-tensioned prestressed concrete beam (7), the post-tensioned prestressed tendon one (17) and the post-tensioned prestressed tendon two (9) are embedded in the beam according to the design position, and enough length is reserved at both ends, and then the concrete is poured, and when the concrete is cured to enough strength, the post-tensioned prestressed tendon one (17) is tensioned and fixtures and anchorage devices are arranged at both ends; wherein when the post-tensioned prestressed tendon one (17) and the post-tensioned prestressed tendon two (9) are unbounded or slow-bonded prestressed tendons, they are directly embedded in the design position; when the post-tensioned prestressed tendon one (17) and the post-tensioned prestressed tendon two (9) are bonded prestressed tendons, corrugated pipes need to be embedded in the prefabricated concrete beam (7);

[0064] 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 reinforcement (6) according to the design requirements;

[0065] Step 3: Hoist the prefabricated post-tensioned prestressed concrete open-hole beam (7) to the top surface of the prefabricated concrete lower column (2), make the bottom surface of the prefabricated post-tensioned prestressed concrete open-hole beam (7) flush with the top surface of the prefabricated concrete lower column (2), make the end of the prefabricated post-tensioned prestressed concrete open-hole beam (7) rest on the prefabricated concrete lower column (2), and fix it with supports, and since there is a prestressed effect in the beam, supports can also be omitted; wherein the ordinary steel bars (10) extended from the two side post-tensioned prestressed concrete open-hole beams (7) and the node core area are reasonably avoided and directly anchored;

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

[0067] Step 5: The top longitudinal reinforcement (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 post-tensioned prestressed tendon two (9) embedded in the post-tensioned prestressed concrete opening beam (7) and extending out is tied well in the node core area according to the design position (when the post-tensioned prestressed tendon two (9) is a bonded prestressed tendon, a section of bellows is embedded in the node core area to form a whole with the bellows embedded in the post-tensioned prestressed concrete opening beam (7); when the tendon is a slow-bonding tendon, a sleeve is needed to be sleeved on the slow-bonding tendon in the non-bonding part of the node), 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 (8) part;

[0068] Step 6: After the UHPC node core area (4) is cured to sufficient strength, the prefabricated concrete flat plate (or composite plate, double-T plate, secondary beam) (19) is hoisted to the prefabricated concrete beam (7) and is fixed;

[0069] Step 7: The beam composite layer (8) and the plate composite layer (20) are poured;

[0070] Step 8: After the beam composite layer (8) and the plate composite layer (20) are cured to sufficient strength, the post-tensioned prestressed tendon two (9) is tensioned (when the post-tensioned prestressed tendon two (9) is a bonded prestressed tendon, the tendon is first passed in the bellows and then is tensioned, finally the bellows in the bonding part of the beam and the node is grouted, and the non-bonding prestressed tendon part of the node is not grouted);

[0071] Step 9: The above manufacturing process is repeated to complete the double post-tensioned prefabricated prestressed concrete opening beam frame structure system.

[0072] 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. 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. These improvements and changes are within the protection scope of the present application.

Claims

1. A UHPC connected double post-tensioned precast prestressed concrete open-hole beam frame structure system, comprising a precast concrete upper column (1), a precast concrete lower column (2), a double post-tensioned precast prestressed concrete open-hole 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 double post-tensioned precast prestressed concrete open-hole composite beam (3) is provided with a precast post-tensioned prestressed concrete open-hole beam (7), a beam composite layer (8) and a post-tensioned prestressed tendon (9), the precast post-tensioned prestressed concrete open-hole beam (7) is provided with ordinary reinforcement (10) and post-tensioned prestressed tendon (17) at the bottom, and is provided with a hanging tendon (21) or a steel mesh (22) around the hole, the steel mesh adopts a welded steel mesh, the beam composite layer (8) is provided with a top longitudinal 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 post-tensioned prestressed tendon (17) extend out of the end surface of the precast post-tensioned prestressed concrete open-hole beam (7) and are directly anchored in the UHPC node core area (4) ; The double post-tensioned precast prestressed concrete open-hole composite beam (3) is a full precast prestressed concrete open-hole beam; The post-tensioned prestressed tendon (17) is only tensioned in the precast post-tensioned prestressed concrete open-hole beam (7), and the post-tensioned prestressed tendon (9) is tensioned together with the column outside in the precast post-tensioned prestressed concrete open-hole beam (7) ; The post-tensioned prestressed tendon (17) and the post-tensioned prestressed tendon (9) comprise straight, folded and curved prestressed tendons; The post-tensioned prestressed tendon (17) and the post-tensioned prestressed tendon (9) are unbounded, slowly bounded or bonded prestressed tendons; The post-tensioned prestressed tendon (17) is calculated for effective prestress when considering self weight and construction load in the construction stage, and is calculated for actual bonding condition of the prestressed tendon when calculating normal use or ultimate bearing capacity, and is calculated for bonding and unbounded respectively; The post-tensioned prestressed tendon (9) is bonded, partially bonded, unbounded or unbounded in the node core area. The double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) is calculated according to the post-tensioning prestressed concrete open-hole simple 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), the plate composite layer (20), when the node and the composite layer concrete strength reaches the design requirement, the post-tensioning prestressed tendon two (9) is tensioned, and after the tensioning is completed, the construction stage calculation is carried out according to the un-bonded prestressed tendon; the double post-tensioning prefabricated prestressed concrete open-hole composite beam is different in the section of the upper chord at the hole before pouring the beam composite layer, the plate composite layer and the UHPC node core area and after pouring, and the stress state is also different, so the upper chord and the lower chord of the prefabricated post-tensioning prestressed concrete open-hole beam hole are calculated; when the normal use or the ultimate bearing capacity is calculated, the post-tensioning prestressed tendon two (9) is calculated according to the actual bonding condition of the prestressed tendon respectively according to the bonding and the un-bonding; for the un-bonding part of the post-tensioning prestressed tendon two (9) in the node core area, the restoring performance provided by the un-bonding part is considered under the earthquake load; The post-tensioning prestressed tendon two (9) is arranged in the prefabricated post-tensioning prestressed concrete open-hole beam (7) component, passes through the UHPC node core area (4) and extends out of the UHPC node core area (4) at both ends, and clamps (15) and anchors (16) are respectively arranged at both ends, one end is arranged outside the column, and the other end is arranged in the beam composite layer; The edge node, the middle node and the corner node core area of the double post-tensioning prefabricated prestressed concrete open-hole beam frame structure system are all UHPC node core areas (4); The stirrups in the UHPC node core area (4) are arranged according to the design requirement, 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 the contribution of the steel fibers to the shear resistance of the node core area is considered. The construction method of the double post-tensioning prefabricated prestressed concrete open-hole beam frame structure system comprises the following steps: The end of the prefabricated post-tensioning prestressed concrete open-hole 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 surrounded by the prefabricated post-tensioning prestressed concrete open-hole beam (7), the prefabricated concrete lower column and the prefabricated concrete upper column is the UHPC node core area.

2. The UHPC connected dual post-tensioned precast prestressed concrete perforated beam framed structural system according to claim 1, wherein, The double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) is composed of a prefabricated post-tensioning prestressed concrete open-hole beam (7), a beam composite layer (8) and a post-tensioning prestressed tendon two (9); and the composite plate (18) is composed of a prefabricated concrete plate (19) and a plate composite layer (20) poured on the plate.

3. The UHPC connected dual post-tensioned precast prestressed concrete perforated beam framing 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 double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) are provided with recesses.

4. The UHPC connected dual post-tensioned precast prestressed concrete perforated beam framing system of claim 1, wherein, The stirrups in the prefabricated concrete upper column (1), the prefabricated concrete lower column (2) and the double post-tensioning prefabricated prestressed concrete open-hole composite beam (3) are divided into dense areas and non-dense areas.

5. The UHPC connected dual post-tensioned precast prestressed concrete perforated beam framing system of claim 1, wherein, The top surface of the prefabricated post-tensioning prestressed concrete open-hole beam (7) and the prefabricated concrete plate (19) is provided with a rough surface layer.

6. A design method of a UHPC connected post-tensioned slow-bonded co-tensioned precast prestressed concrete frame structural system according to claim 1, characterized in that: The hole position in the beam should be located in the middle 1 / 3 section as far as possible, and when located in the beam end 1 / 3 section, the distance from the hole edge close to 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 double post-tensioned precast prestressed concrete opening beam frame structure 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 post-tensioned prestressed concrete hole beam (7), prefabricated concrete slab (19) are made; wherein the prefabricated concrete lower column (2), the prefabricated concrete upper column (1) extends the longitudinal reinforcement anchor into the node core area (4) and needs to reserve enough anchoring length; when making the prefabricated post-tensioned prestressed concrete hole beam (7), the post-tensioned prestressed tendon one (17) and the post-tensioned prestressed tendon two (9) are embedded in the beam according to the design position, and enough length is reserved at both ends, and then the concrete is poured, the post-tensioned prestressed tendon one (17) is tensioned when the concrete is cured to enough strength, and clamps and anchors are arranged at both ends; wherein the post-tensioned prestressed tendon one (17) and the post-tensioned prestressed tendon two (9) are directly embedded in the design position when they are unbonded or slow-bonded prestressed tendons; when the post-tensioned prestressed tendon one (17) and the post-tensioned prestressed tendon two (9) are bonded prestressed tendons, a bellows pipe needs to be embedded in the prefabricated post-tensioned prestressed concrete hole beam (7); Step 2: after the prefabricated components are cured, the prefabricated concrete lower column (2) is hoisted and installed on the foundation, then a proper number of stirrups are installed on the extended longitudinal main reinforcement (6) according to the design requirements; Step 3: the prefabricated post-tensioned prestressed concrete hole beam (7) is hoisted to the top surface of the prefabricated concrete lower column (2), the bottom surface of the prefabricated post-tensioned prestressed concrete hole beam (7) is flush with the top surface of the prefabricated concrete lower column (2), the end part of the prefabricated post-tensioned prestressed concrete hole beam (7) is placed on the prefabricated concrete lower column (2) and is fixed with support, and since the beam has a prestressed effect, the support can be omitted; wherein the ordinary steel bars (10) extended from the post-tensioned prestressed concrete hole beams (7) on both sides and the node core area are reasonably avoided and directly anchored according to the structural requirements; 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 installed in step 2 are bound together with the column longitudinal reinforcement; wherein the longitudinal reinforcement extended from the prefabricated concrete upper and lower columns is reasonably avoided and directly anchored in the node core area; Step 5: the top long steel bar (11) is passed through the stirrups reserved in the beam composite layer area and the node core area (4) and is bound well, then the post-tensioned prestressed tendon two (9) embedded in the post-tensioned prestressed concrete hole beam (7) and extended is bound well in the node core area according to the design position, when the post-tensioned prestressed tendon two (9) is a bonded prestressed tendon, a section of bellows pipe is embedded in the node core area to form a whole with the bellows pipe embedded in the post-tensioned prestressed concrete hole beam (7); when the post-tensioned prestressed tendon two (9) is a slow-bonded prestressed tendon, a sleeve pipe is needed to be sleeved on the slow-bonded tendon, 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 (8) part; Step 6: After the UHPC node core area (4) is cured to sufficient strength, the prefabricated concrete slab, laminated slab, double T slab or secondary beam is hoisted to the prefabricated post-tensioned concrete opening beam (7) and fixed; Step 7: Pouring the beam laminated layer (8) and the slab laminated layer (20); Step 8: After the beam laminated layer (8) and the slab laminated layer (20) are cured to sufficient strength, the post-tensioned tendon two (9) is tensioned, when the post-tensioned tendon two (9) is a bonded prestressed tendon, the tendon is first threaded in the bellows and then tensioned, and finally the bellows in the bonded part of the beam and the node is grouted, and the unbonded prestressed tendon part of the node is not grouted; Step 9: Repeat the above manufacturing process to complete the double post-tensioned prefabricated prestressed concrete opening beam frame structure system.

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