Precast prestressed frame structure combined with pre-tensioning method and post-tensioning method and construction method thereof

Abstract

The application relates to a prefabricated prestressed frame structure combining the pre-tensioning method and the post-tensioning method and a construction method thereof. The structure comprises a plurality of prefabricated columns, prefabricated beams and secondary beams. The prefabricated columns are vertically installed on the foundation, the longitudinal unbonded prestressed tendons are anchored in the prefabricated columns along the length direction, and the longitudinal unbonded prestressed tendons penetrate the prefabricated columns. The two ends of the prefabricated beams are respectively connected with two adjacent prefabricated columns perpendicularly, the two adjacent prefabricated beams are perpendicular to each other, the first transverse prestressed tendons penetrating the beam bodies are arranged in the prefabricated beams along the length direction, and the two ends of the prefabricated beams are respectively provided with the second transverse prestressed tendons. The secondary beams are arranged in one direction, and the two ends of the secondary beams are respectively connected with two prefabricated beams perpendicularly. The secondary beams and the prefabricated beams are fully paved with the concrete slabs, and the floor laminated layers are cast on the concrete slabs. The structure solves the problems that the traditional pre-tensioning method structure has a large reverse arch and is prone to cracks, reduces the cost and construction difficulty, and is suitable for the warehouse buildings with large span and large bearing load.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of prefabricated structure, in particular to a prefabricated prestressed frame structure combining pre-tensioning method and post-tensioning method and a construction method thereof. BACKGROUND

[0002] The prefabricated structure refers to a building manufactured in a factory or other manufacturing site and transported to a predetermined destination after completion, which can improve production efficiency, ensure construction period and save cost during construction process. 2 For example, in the existing multi-story logistics warehouse, the column grid size is usually 11-12m in two directions, and the standard value of live load of the floor is usually 20-30kN / m

[0003] In the prefabricated structure technology, the pre-tensioning method and the post-tensioning method are generally divided according to the sequence of tensioning the prestressed tendon. The post-tensioning method refers to tensioning the prestressed tendon in the component or structure with a certain strength of concrete and permanently fixing it with an anchor, so that the concrete generates a pre-compressive stress, and finally the cement slurry is poured into the hole to form a whole with the prestressed steel strand and the concrete component so as to work cooperatively. The pre-tensioning method refers to tensioning the prestressed steel strand on the tensioning pedestal before pouring the concrete, then pouring the concrete, curing the concrete to reach the specified strength, and then relaxing and cutting off the prestressed steel strand. The post-tensioning production process is relatively simple, but the construction process is complicated, a special anchor needs to be provided, the concentrated force under the anchor is large, a dense reinforcing steel bar needs to be provided, the embedded corrugated pipe and the reinforcing bar under the anchor make it difficult to vibrate the concrete below the corrugated pipe and under the anchor, and the compaction process is prone to compaction not being dense or hole blocking. The pre-tensioning method of prestressed concrete component has the characteristics of short construction period, good component durability, reliable force transmission, less maintenance and repair work, and easier to ensure engineering quality, compared with the post-tensioning method, the pre-tensioning method does not need to configure a special anchor, because it relies on the bonding force between the steel strand and the concrete to transfer the prestress, the anchor can be reused, and the material is saved.

[0004] However, in the traditional pre-tensioning method, since all the reinforcement is arranged in a straight line along the beam bottom, the bottom compressive stress and the top tensile stress are too large under the superimposed effect of external load and prestress reverse load, which causes reverse arch and crack phenomenon, so it is only suitable for small and medium span structures. In summary, both the pre-tensioning method and the post-tensioning method in the traditional prefabricated structure technology have deficiencies and need to be further improved. SUMMARY

[0005] Therefore, it is necessary to provide a prefabricated prestressed frame structure combined with the pretensioning method and the post-tensioning method, which is suitable for large span and large load bearing, and has more uniform stress of prestressed tendons at the top and bottom during tensioning, less cracks at the top of the midspan, and more ideal overall seismic performance.

[0006] A prefabricated prestressed frame structure combined with the pretensioning method and the post-tensioning method, comprising:

[0007] a plurality of prefabricated columns vertically installed on a foundation, the prefabricated columns internally having longitudinally unbonded prestressed tendons anchored along the length direction, the longitudinally unbonded prestressed tendons penetrating the prefabricated columns;

[0008] a plurality of prefabricated beams, two ends of each prefabricated beam being vertically connected to two adjacent prefabricated columns, and two adjacent prefabricated beams being perpendicular to each other, the prefabricated beams internally having first transverse prestressed tendons penetrating the beam bodies along the length direction, and two ends of each prefabricated beam further having second transverse prestressed tendons;

[0009] a plurality of secondary beams, the secondary beams being arranged in one direction, and two ends of each secondary beam being vertically connected to two prefabricated beams, the secondary beams and the prefabricated beams being fully paved with concrete slabs, and the concrete slabs having floor laminated layers cast thereon;

[0010] wherein the first transverse prestressed tendons are pretensioning prestressed tendons in the shape of broken lines, the longitudinally unbonded prestressed tendons and the second transverse prestressed tendons are post-tensioning prestressed tendons.

[0011] In one of the embodiments, the prefabricated beams are connected to the prefabricated columns through beam-column joint areas, the beam-column joint areas being cast with concrete and embedded with prestressed anchors, the prestressed anchors being used to anchor the longitudinally unbonded prestressed tendons, the first transverse prestressed tendons and the second transverse prestressed tendons.

[0012] In one of the embodiments, the longitudinally unbonded prestressed tendons are symmetrically arranged about the center of each prefabricated column, and the first transverse prestressed tendons and the second transverse prestressed tendons are symmetrically arranged about the beam section of each prefabricated beam, respectively.

[0013] In one of the embodiments, the second transverse prestressed tendons are divided into one-way prestressed tendons and two-way prestressed tendons, one end of each one-way prestressed tendon extending into the beam-column joint area, and one end of each two-way prestressed tendon extending into and penetrating the beam-column joint area.

[0014] In one of the embodiments, the top end of each prefabricated beam is provided with a tensioning notch, and each prefabricated beam is internally provided with a pre-embedded part, and the secondary beams and the prefabricated beams are fixedly connected through the pre-embedded parts.

[0015] In one of the embodiments, the length of the precast beam is set between 10 to 13 m, the length of the unidirectional prestressed tendon is one third of the length of the precast beam, and the length of the bidirectional prestressed tendon is two thirds of the length of the precast beam.

[0016] In one of the embodiments, the precast beams are arranged at intervals along the length direction of the precast column, and each precast column is divided into multiple segments with the same length, and the length of each segment is the net height of a floor.

[0017] In one of the embodiments, the concrete slab is a precast prestressed concrete slab, which is made of a prestressed large-hole composite slab or a PK prestressed composite slab.

[0018] A construction method of a precast prestressed frame structure combining the pre-tensioning method and the post-tensioning method, the method comprising:

[0019] The precast column, the precast beam and the secondary beam are hoisted and positioned, and the secondary beam is fixed through the embedded part in the precast beam, the precast beam is internally provided with the first transverse prestressed tendon penetrating the beam body along the length direction, and the two ends of the precast beam are further respectively provided with the second transverse prestressed tendon;

[0020] The beam-column joint area is grouted to fixedly connect the precast column and the precast beam, and the tensioning and anchoring of the second transverse prestressed tendon are completed through the prestressed anchor;

[0021] The concrete slab is fully paved between the precast beam and the secondary beam, and the steel bar mesh of the floor composite layer is bound to complete the grouting of the floor composite layer;

[0022] The longitudinal unbonded prestressed tendon is penetrated through the precast column in a whole bundle to complete the tensioning and anchoring of the longitudinal unbonded prestressed tendon.

[0023] In one of the embodiments, before the precast column, the precast beam and the secondary beam are hoisted and positioned, and the secondary beam is fixed through the embedded part in the precast beam, it further comprises:

[0024] The precast column, the precast beam, the secondary beam and the concrete slab are produced in a factory according to the design scheme, the precast beam is internally provided with the first transverse prestressed tendon and the second transverse prestressed tendon, and the tensioning and anchoring of the first transverse prestressed tendon are completed before the precast beam is grouted;

[0025] It is checked whether the precast column is provided with the corbelling column, if yes, the corbelling column is subjected to the mortar setting treatment, and if not, the temporary support is arranged at the bottom of the two ends of the precast beam.

[0026] The prefabricated prestressed frame structure combined with the pre-tensioning method and the post-tensioning method and the construction method thereof, through the broken line pre-tensioning method, the first transverse prestressed tendon is tensioned before pouring the prefabricated beam, the pouring quality of the beam end concrete is improved, and the diagonal cracks of the beam end are reduced; the post-tensioned longitudinal unbonded prestressed tendon is arranged along the height range of the prefabricated column, so as to generate pre-compressive stress, the frame structure has a certain self-resetting capacity for deformation under the action of horizontal load, and the seismic performance of the structure is improved; and the second transverse prestressed tendon is post-tensioned at both ends of the prefabricated beam, so that the prestressed tendons at the top and the bottom are uniformly stressed during tensioning, and the structure is suitable for larger-span and larger-load logistics and storage structures. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is a top view of the prefabricated prestressed frame structure combined with the pre-tensioning method and the post-tensioning method in one embodiment of the present application.

[0028] Figure 2 It is a sectional view of the prefabricated prestressed frame structure combined with the pre-tensioning method and the post-tensioning method in one embodiment of the present application.

[0029] Figure 3 It is a schematic diagram of a beam-column joint area in one embodiment of the present application.

[0030] Figure 4 It is a schematic diagram of a beam-column joint area in another embodiment of the present application.

[0031] Figure 5 It is a schematic diagram of a beam-column joint area in another embodiment of the present application.

[0032] Figure 6 It is a flow chart of the construction method of the prefabricated prestressed frame structure combined with the pre-tensioning method and the post-tensioning method in one embodiment of the present application.

[0033] Figure 7 It is a flow chart of the construction method of the prefabricated prestressed frame structure combined with the pre-tensioning method and the post-tensioning method in another embodiment of the present application.

[0034] In the figure: 100, prefabricated column; 110, longitudinal unbonded prestressed tendon; 200, prefabricated beam; 210, first transverse prestressed tendon; 220, second transverse prestressed tendon; 221, bidirectional prestressed tendon; 222, unidirectional prestressed tendon; 300, secondary beam; 400, concrete slab; 500, floor slab composite layer; 600, beam-column joint area. DETAILED DESCRIPTION

[0035] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely explain the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort should fall into the scope of the present application.

[0036] It should be noted that when a component is referred to as being "on" or "set on" another component, it can be directly on the other component or there can be a middle component. When a component is referred to as being "connected" to another component, it can be directly connected to the other component or there can be a middle component. The terms "vertical", "horizontal", "upper", "lower", "left", "right", and similar expressions used in the description of the present application are for the purpose of illustration only and do not indicate the only orientation of the embodiments.

[0037] In addition, the terms "first", "second", and the like are used only to describe and distinguish the associated elements and are not otherwise intended to indicate or imply a relative importance or a quantity limitation of the indicated elements. Thus, a feature defined with "first" or "second" can include at least one of the feature, explicitly or implicitly. In the description of the present application, the meaning of "a plurality of" is at least two, for example, two, three, and the like, unless otherwise explicitly and specifically limited.

[0038] In the present application, unless otherwise explicitly and specifically defined, "on", "under", "above", and "over" of a first feature to a second feature can mean that the first feature is in direct contact with the second feature, or the first feature is in indirect contact with the second feature through an intermediate medium. Moreover, "above", "over", and "on" of a first feature to a second feature can mean that the first feature is directly above or obliquely above the second feature, or only means that the first feature is horizontally higher than the second feature. "Below", "under", and "underneath" of a first feature to a second feature can mean that the first feature is directly below or obliquely below the second feature, or only means that the first feature is horizontally lower than the second feature.

[0039] Unless otherwise defined, all technical and scientific terms used in the specification of the present application have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used in the specification of the present application includes any and all combinations of one or more of the associated listed items.

[0040] As Figure 1 With Figure 2As shown, in one embodiment, a prefabricated prestressed frame structure combining pre-tensioning method and post-tensioning method includes a plurality of prefabricated columns 100, prefabricated beams 200 and secondary beams 300, wherein the prefabricated columns 100 are vertically installed on the foundation, the longitudinal unbonded prestressed tendons 110 are anchored and arranged along the length direction inside the prefabricated columns 100, and the longitudinal unbonded prestressed tendons 110 pass through the prefabricated columns 100; the two ends of the prefabricated beams 200 are respectively connected to two adjacent prefabricated columns 100 vertically, and the two adjacent prefabricated beams 200 are perpendicular to each other, the first transverse prestressed tendons 210 passing through the beam body are arranged along the length direction inside the prefabricated beams 200, and the second transverse prestressed tendons 220 are also arranged at the two ends of the prefabricated beams 200 respectively; all the secondary beams 300 are arranged in one direction, and the two ends thereof are respectively connected to two prefabricated beams 200 vertically, and the secondary beams 300 and the prefabricated beams 200 are fully paved with the concrete slabs 400, and the floor composite layers 500 are cast on the concrete slabs 400. The structure solves the problems of unreasonable stress, large reverse arch and easy cracking of the traditional straight pre-tensioning method, reduces the labor cost and the complexity of post-tensioning with bonding construction, and thus improves the construction speed. The prestressed tenders are uniformly stressed during tensioning, are not prone to cracking, and have ideal seismic performance, and are suitable for large-span and large-load logistics and storage buildings.

[0041] It should be noted that the first transverse prestressed tendons 210 are folded line pre-tensioning method prestressed tendons, and the longitudinal unbonded prestressed tendons 110 and the second transverse prestressed tendons 220 are post-tensioning method prestressed tendons.

[0042] The prefabricated prestressed frame structure combining pre-tensioning method and post-tensioning method improves the pouring quality of the beam end concrete by pre-tensioning the first transverse prestressed tendons 210 by folded line pre-tensioning method before pouring the prefabricated beams 200, reduces the diagonal cracks at the beam end, post-tensions the longitudinal unbonded prestressed tendons 110 along the column height range of the prefabricated columns 100 to generate pre-compressive stress, so that the frame structure has a certain self-resetting ability for deformation under horizontal load, and improves the seismic performance of the structure, and post-tensions the second transverse prestressed tendons 220 at the two ends of the prefabricated beams 200, so that the prestressed tendons at the top and the bottom are uniformly stressed during tensioning, and are suitable for larger-span and larger-load logistics and storage structures.

[0043] In the embodiment, the prefabricated beams 200 are connected to the prefabricated columns 100 through beam-column joint areas 600, the beam-column joint areas 600 are cast by concrete and embedded with prestressed anchors, and the prestressed anchors are used to anchor the longitudinal unbonded prestressed tendons 110, the first transverse prestressed tendons 210 and the second transverse prestressed tendons 220.

[0044] Specifically, the beam-column joint area 600 is formed by the intersection of the reinforcement cage of the precast beam 200 and the precast column 100 and pouring concrete. When the concrete strength of the beam-column joint area 600 reaches a specified strength (generally not less than 75% of the design strength standard value), the tensioning and anchoring of the second transverse prestressed tendon 220 are completed, the pre-tensioning force of the second transverse prestressed tendon 220 is transmitted to the concrete by the prestressed anchor at the end of the component, so that the pre-compressive stress is generated in the concrete, and finally the cement slurry is poured to make the second transverse prestressed tendon 220 and the concrete component form an integral whole.

[0045] It should be noted that the precast beam 200 is made by post-tensioning process, and a tensioning end anchor is also embedded in the interior. The tensioning end anchor and the prestressed anchor act together to anchor the longitudinal unbonded prestressed tendon 110, the first transverse prestressed tendon 210 and the second transverse prestressed tendon 220, wherein the prestressed anchor is a prestressed fixed end anchor.

[0046] In the present embodiment, the longitudinal unbonded prestressed tendon 110 is symmetrically arranged about the center of each precast column 100, and the first transverse prestressed tendon 210 and the second transverse prestressed tendon 220 are respectively symmetrically arranged about the beam section of each precast beam 200. Specifically, the prestressed tendons are symmetrically arranged in the interior of each precast column 100 and precast beam 200 respectively, forming a symmetrical structure to increase the maximum load that the floor can bear.

[0047] In the present embodiment, the second transverse prestressed tendon 220 is divided into a unidirectional prestressed tendon 222 and a bidirectional prestressed tendon 221. One end of the unidirectional prestressed tendon 222 extends into the beam-column joint area 600, and one end of the bidirectional prestressed tendon 221 extends into and penetrates the beam-column joint area 600.

[0048] Specifically, in the present precast prestressed frame structure, more precast columns 100 can be provided according to different design schemes to form a larger floor area. At this time, the number of precast beams 200 connected to the same precast column 100 is not less than two, wherein the two precast beams 200 connected to opposite surfaces of the same precast column 100 share one second transverse prestressed tendon 220, which is a bidirectional prestressed tendon 221. The bidirectional prestressed tendon 221 penetrates the beam-column joint area 600 and is anchored with the prestressed anchor, and the two ends are located in the two precast beams 200 respectively. If only one precast beam 200 is connected to one surface of a precast column 100, the second transverse prestressed tendon 220 inside the precast beam 200 connected to one end of the precast column 100 is a unidirectional prestressed tendon 222. One end of the unidirectional prestressed tendon 222 is located inside the precast beam 200, and the other end extends into the beam-column joint area 600 and is anchored with the prestressed anchor.

[0049] It should be noted that the precast column 100 connecting four precast beams 200 at the same horizontal height is a middle column, and the middle column node plan view is as shown in Figure 3The edge column is connected with three precast beams 200 at the same horizontal level, and the edge column node plan view is as shown in FIG. 4; Figure 4 The corner column is connected with two precast beams 200 at the same horizontal level, and the corner column node plan view is as shown in FIG. 5. Figure 5 The middle column is connected with two pairs of precast beams 200 (each pair is two precast beams 200 connected to opposite sides of the precast column 100) through two pairs of bidirectional prestressed tendons 221, and the two pairs of precast beams 200 are perpendicular to each other; the edge column is connected with one pair of precast beams 200 and one precast beam 200 through one pair of bidirectional prestressed tendons 221 and one pair of unidirectional prestressed tendons 222, and the single precast beam 200 is perpendicular to the pair of precast beams 200; the corner column is connected with two precast beams 200 through two pairs of unidirectional prestressed tendons 222, and the two precast beams 200 connected by the corner column are perpendicular to each other.

[0050] In the embodiment, the top end of the precast beam 200 is provided with a tensioning notch, and the precast beam 200 is internally provided with a pre-embedded part. The secondary beam 300 is fixedly connected with the precast beam 200 through the pre-embedded part. Specifically, the pre-embedded part is a structural component placed during structure pouring, used for lapping during upper structure masonry, facilitating the installation and fixation of external engineering equipment foundation, and can be made of steel bars or cast iron and the like metals, so as to ensure the stability of the connection structure between the secondary beam 300 and the precast beam 200. The tensioning notch is pre-set at the top end of the precast beam 200, so as to facilitate the tensioning and anchoring of the second transverse prestressed tendon 220 during construction.

[0051] In the embodiment, the length of the precast beam 200 is set to be between 10 to 13 m, the length of the unidirectional prestressed tendon 222 is one third of the length of the precast beam 200, and the length of the bidirectional prestressed tendon 221 is two thirds of the length of the precast beam 200. Specifically, the column grid size in the logistics and storage structure is generally the same and is set to be between 10 to 13 m. The two ends of each precast beam 200 are provided with the second transverse prestressed tendon 220, wherein one third of the length of the precast beam 200 is used to make the unidirectional prestressed tendon 222, and two thirds of the length of the precast beam 200 is used to make the bidirectional prestressed tendon 221, so that the part of the second transverse prestressed tendon 220 located in the precast beam 200 can equally divide the precast beam 200, thereby increasing the span and load of the logistics and storage structure and saving the use of materials.

[0052] In the embodiment, the prefabricated beams 200 are arranged at intervals along the length direction of the prefabricated columns 100, and each prefabricated column 100 is divided into multiple segments with the same length, and the length of each segment is the net height of a floor. Specifically, due to different construction schemes, multiple-story structures may be needed to be built in the specific construction process of the logistics warehouse building, and at this time, multiple prefabricated beams 200 need to be arranged at intervals on the prefabricated column 100, and the concrete slab 400 is fully paved on the prefabricated beams 200 and the secondary beams 300 at the same horizontal height, and the floor slab composite layer 500 is poured to form a floor, wherein the distance between every two adjacent prefabricated beams 200 along the length direction of the prefabricated column 100 is the net height of the floor.

[0053] It should be noted that the prefabricated column 100 can be produced by sectional prefabrication, and the sectional length of the column is the height of the floor minus the height of the prefabricated beam 200.

[0054] In the embodiment, the concrete slab 400 is a prefabricated prestressed concrete slab, and specifically, a prestressed large-hole composite slab or a PK prestressed composite slab can be used. Specifically, the prefabricated prestressed concrete slab is formed by adding steel bars and welding keel trusses on the basis of high-strength fiber cement pressure plates, and the surface of the prefabricated prestressed concrete slab is provided with grooves which act together with the steel bar keel truss to increase the adhesion of the concrete and make the building structure more stable. At the same time, the prefabricated prestressed concrete slab does not need to be disassembled twice during construction, and can be directly used for concrete pouring, which can greatly shorten the construction period, save labor, and will not produce construction waste due to secondary disassembly.

[0055] As shown in FIG. 1, Figure 6 In one embodiment, a construction method of a prefabricated prestressed frame structure combining the pretensioning method and the post-tensioning method includes the following steps:

[0056] In step S610, the prefabricated column, the prefabricated beam, and the secondary beam are hoisted and positioned, and the secondary beam is fixed through the embedded part in the prefabricated beam. The prefabricated beam is provided with first transverse prestressed tendons penetrating through the beam body along the length direction, and the two ends of the prefabricated beam are further provided with second transverse prestressed tendons.

[0057] Specifically, according to the construction scheme design, each component is hoisted and positioned, and the secondary beam is fixedly connected with the prefabricated beam through the embedded part to ensure the stability of the connection structure between the secondary beam and the prefabricated beam.

[0058] In step S620, the beam-column joint area is poured to fixedly connect the prefabricated column and the prefabricated beam, and the tensioning and anchoring of the second transverse prestressed tendons are completed through the prestressed anchorage device.

[0059] Specifically, the beam-column joint area is formed by the intersection of the precast beam's reinforcement cage and the precast column, and then poured with concrete. The precast beam and precast column are fixedly connected through the beam-column joint area. When the concrete strength of the beam-column joint area reaches the specified strength (generally not less than 75% of the design strength standard value), the tensioning and anchoring of the second transverse prestressing tendons are completed. The prestressing force of the second transverse prestressing tendons is transmitted to the concrete by the prestressing anchors at the ends of the component and the prestressing tensioning end anchors in the precast beam, causing precompressive stress. Finally, cement slurry is poured to integrate the second transverse prestressing tendons with the concrete component. The prestressing anchors are prestressing fixed end anchors.

[0060] Step S630: fully lay the concrete slab between the precast beam and the secondary beam, and tie the steel mesh of the floor slab superimposed layer to complete the pouring of the floor slab superimposed layer.

[0061] Specifically, the concrete slab adopts prestressed large-hole composite slab or PK prestressed composite slab, which is fully laid between the precast beams and the secondary beams, and the floor slab composite layer is poured to form a floor and complete the structural construction of a single level.

[0062] Step S640: Insert the entire bundle of longitudinal unbonded prestressed tendons through the prefabricated column to complete the tensioning and anchoring of the longitudinal unbonded prestressed tendons.

[0063] Specifically, complete the connection of the prefabricated column's embedded hole pipes, insert the entire bundle of longitudinal unbonded prestressed tendons into the prefabricated column, and tension and anchor them according to design requirements to complete the construction of the entire structure.

[0064] In this embodiment, if the building to be constructed is a multi-story structure, steps S610 to S630 are repeated to form a multi-story structure.

[0065] like Figure 7 As shown, in this embodiment, the prefabricated columns, prefabricated beams and secondary beams are hoisted into place, and the secondary beams are fixed by embedded parts in the prefabricated beams, and the following steps are also included before:

[0066] Step S710: Precast columns, precast beams, secondary beams and concrete slabs are standardizedly produced in the factory according to the design plan. First transverse prestressed tendons and second transverse prestressed tendons are arranged inside the precast beams, and the tensioning and anchoring of the first transverse prestressed tendons are completed before the precast beams are cast.

[0067] Specifically, each structural member is produced according to design drawings in the factory, wherein the prefabricated beam is produced by using the pretensioning method in the factory, first, the formwork of the prefabricated beam and the hoisting reinforcement cage are installed on the prefabricated pedestal, and the first and second transverse prestressed tendons are installed according to the design position, then the first transverse prestressed tendon is tensioned and anchored, finally the concrete is poured, maintained and the first transverse prestressed tendon is released, thus the production of the prefabricated beam is completed. By using the broken line reinforcement pretensioning method, the functions of high-strength concrete and steel can be fully utilized, the pouring quality of the beam end concrete is improved, the diagonal cracks at the beam end can be correspondingly reduced, and the amount of ordinary steel bars can also be reduced.

[0068] In step S720, it is checked whether the corbel column is arranged on the prefabricated column, if yes, the corbel column is subjected to the mortar setting treatment, and if no, the temporary support is arranged at the bottom of the two ends of the prefabricated beam.

[0069] Specifically, in the hoisting process of the prefabricated column and the prefabricated beam, the corbel column can assist the alignment process of the two, if the top end of the prefabricated column is provided with the corbel column, the corbel column is subjected to the mortar setting treatment, and if the top end of the prefabricated column is not provided with the corbel column, the temporary support is arranged at the bottom of the two ends of the prefabricated beam, which can assist the alignment and ensure the stability of the structure in the construction process.

[0070] The construction method of the prefabricated prestressed frame structure combining the pretensioning method and the post-tensioning method, uses the broken line pretensioning method to pour the prefabricated beam, transports and hoists the components to the position, connects the secondary beam and the prefabricated beam by using the embedded part, pours the core area of the beam column, completes the post-tensioning of the second transverse prestressed tendon, ensures the stability of the structure, finally fully pours the concrete slab, pours the floor superimposed layer, and completes the post-tensioning of the longitudinal unbonded prestressed tendon. By using the pretensioning first transverse prestressed tendon, the pouring quality of the beam end concrete is improved, and the diagonal cracks at the beam end are reduced; by using the post-tensioning second transverse prestressed tendon, the prestressed tendons at the top and the bottom are uniformly stressed when tensioned; by using the post-tensioning longitudinal unbonded prestressed tendon, the prefabricated column generates the pre-compressive stress, and the frame structure has a certain self-resetting capacity for the deformation under the action of the horizontal load, which solves the deficiencies in the traditional prefabricated structure technology, and is suitable for the construction of the logistics and storage structure with larger span and larger load.

[0071] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, however, as long as the combinations of the technical features do not exist contradictions, they shall be considered as the scope of the present disclosure.

[0072] The above-described embodiments are merely illustrative of several embodiments of the present application, which are described in more detail and in a specific manner, but should not be construed as limiting the scope of the patent of the present application. It should be noted that, for those of ordinary skill in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A construction method for a prefabricated prestressed frame structure combining pre-tensioning and post-tensioning, characterized in that: The framework structure includes: A plurality of prefabricated columns, each of which is vertically mounted on a foundation, wherein longitudinal unbonded prestressed tendons are anchored along the length of the prefabricated columns, and the longitudinal unbonded prestressed tendons run through the prefabricated columns; A plurality of precast beams, each end of each precast beam being perpendicularly connected to two adjacent precast columns, and each adjacent precast beam being perpendicular to each other, each precast beam being provided with a first transverse prestressed tendon running through the beam body along its length, and each end of each precast beam being provided with a second transverse prestressed tendon; Multiple secondary beams, each of which is arranged in one direction and vertically connected to two precast beams at both ends, with a concrete slab fully paved between the secondary beams and the precast beams, and a floor slab superimposed layer cast on the concrete slab; The first transverse prestressed tendons are prestressed tendons of a broken line type, the longitudinal unbonded prestressed tendons and the second transverse prestressed tendons are post-tensioned prestressed tendons, and the first transverse prestressed tendons and the second transverse prestressed tendons are symmetrically arranged about the beam cross section of each precast beam; The method comprises: hoisting a prefabricated column, a prefabricated beam, and a secondary beam into place, and fixing the secondary beam by means of embedded parts in the prefabricated beam, wherein a first transverse prestressed tendon is provided inside the prefabricated beam along the length direction and runs through the beam body, and second transverse prestressed tendons are provided at both ends of the prefabricated beam; Cast the beam-column joint area to securely connect the precast columns and beams, and complete the tensioning and anchoring of the second transverse prestressed tendons through prestressed anchors; The concrete slab is fully laid between the precast beams and the secondary beams, and the steel mesh of the floor slab superimposed layer is tied to complete the pouring of the floor slab superimposed layer; The entire bundle of longitudinal unbonded prestressed tendons is passed through the prefabricated column to complete the tensioning and anchoring of the longitudinal unbonded prestressed tendons.

2. The construction method of the prefabricated prestressed frame structure combining pre-tensioning and post-tensioning according to claim 1, characterized in that: The prefabricated beam is connected to the prefabricated column through a beam-column node area. The beam-column node area is cast by concrete and embedded with prestressed anchors. The prestressed anchors are used to anchor longitudinal unbonded prestressed tendons, first transverse prestressed tendons and second transverse prestressed tendons.

3. The construction method of the prefabricated prestressed frame structure combining pre-tensioning and post-tensioning according to claim 2, characterized in that: The longitudinal unbonded prestressed tendons are arranged symmetrically about the center of each prefabricated column.

4. The construction method of the prefabricated prestressed frame structure combining pre-tensioning and post-tensioning according to claim 3, characterized in that: The second transverse prestressed tendons are divided into unidirectional prestressed tendons and bidirectional prestressed tendons. One end of the unidirectional prestressed tendons extends into the beam-column node area, and one end of the bidirectional prestressed tendons extends into and passes through the beam-column node area.

5. The construction method of the prefabricated prestressed frame structure combining pre-tensioning and post-tensioning according to claim 1, characterized in that: A tensioning notch is provided at the top of the prefabricated beam, an embedded part is provided inside the prefabricated beam, and the secondary beam and the prefabricated beam are fixedly connected via the embedded part.

6. The construction method of the prefabricated prestressed frame structure combining pre-tensioning and post-tensioning according to claim 5, characterized in that: The length of the prefabricated beam is set between 10 and 13 meters, the length of the unidirectional prestressed tendons is one third of the length of the prefabricated beam, and the length of the bidirectional prestressed tendons is two thirds of the length of the prefabricated beam.

7. The construction method of a prefabricated prestressed frame structure combining pre-tensioning and post-tensioning according to any one of claims 1 to 6, characterized in that: The prefabricated beams are arranged in plurality along the length direction of the prefabricated column, and each prefabricated column is divided into multiple sections of the same length, and the length of each section is the net height of the floor.

8. The construction method of a prefabricated prestressed frame structure combining pre-tensioning and post-tensioning according to claim 7, characterized in that: The concrete slab is a prefabricated prestressed concrete slab, which is made of a prestressed large-hole composite slab or a PK prestressed composite slab.

9. The construction method of a prefabricated prestressed frame structure combining pre-tensioning and post-tensioning according to claim 1, characterized in that: The method further comprises: hoisting the precast columns, precast beams, and secondary beams into place, and fixing the secondary beams with embedded parts in the precast beams, and performing standardized factory production of the precast columns, precast beams, secondary beams, and concrete slabs according to the design plan, providing first and second transverse prestressed tendons in the precast beams, and completing tensioning and anchoring of the first transverse prestressed tendons before casting the precast beams; Check whether the precast columns are equipped with corbels. If so, mortar the corbels. If not, set temporary supports at the bottom of both ends of the precast beams.

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