Fabricated bonded prestressed cross beam column connecting structure and construction method thereof

Abstract

The invention relates to the technical field of fabricated buildings, in particular to a fabricated bonded prestressed cross beam-column connecting structure and a construction method thereof, the connecting structure comprises a prefabricated column, a combined steel rib beam, a superposed T beam, bonded prestressed ribs and a hogging moment resistant rib plate, and the construction technological process comprises field surveying and setting out and field hoisting of the prefabricated column; checking the position of the combined steel rib beam, and grouting a sleeve; hoisting the superposed T beam, and pre-penetrating a middle bolt; reinforcing steel bars in the beam-column joints are treated, prestressed tendon hole channels are distributed, and prestressed tendons are perforated; bolts are perforated, and anti-hogging moment rib plates are installed; hoisting the laminated slab, and mounting an aluminum mold at a beam-column joint; binding reinforcing steel bars of the laminated slab, and checking and accepting a hidden project; integrally pouring concrete of beams, plates and columns, tensioning and anchoring prestressed tendons, and grouting ducts; and flow construction. Compared with a traditional construction method, the construction method has the advantages that the anti-seismic performance is remarkably improved, the construction period is shortened by about 65% or above, the construction cost is reduced by about 40%, and the green construction technical standard requirement is met.

Description

Technical Field

[0001] The present invention relates to the technical field of prefabricated buildings, and in particular to a prefabricated bonded prestressed cross beam-column connection structure and a construction method thereof. Background Art

[0002] The research and application of new prefabricated construction technologies has become one of the important topics in the current development of the industry. my country's promotion of prefabricated buildings is just in the development stage, and the pace of promoting prefabricated buildings in various regions is slow, resulting in a large gap compared with the relevant requirements for the development of green buildings and advanced construction methods. The construction technology system is still imperfect. Through continuous improvement, we can achieve advanced technology and comprehensively consider construction costs and actual industrial production capacity, gradually realize the true transformation and change of prefabricated building construction methods, and comprehensively promote the development of building industrialization.

[0003] In order to achieve the same cast-in-place performance of assembled concrete building structures, the current domestic main method is to use cast-in-place concrete bonding layers to strengthen the connection between prefabricated components. A large number of on-site wet operations bring about common technical problems such as uneven quality and low construction efficiency. Therefore, a new type of reliable connection technology is sought to avoid on-site wet operations and achieve efficient and high-quality construction. In order to solve the problems of efficient construction of assembled construction, such as large installation errors, more construction processes, load-bearing reliability of beam-column nodes, difficulty in installation and adjustment, high construction costs, difficulty in ensuring construction quality, and environmental protection, "an assembled bonded prestressed cross beam-column connection structure and its construction method" is proposed to innovate the design of assembled construction structures, optimize the hoisting and installation process methods, and promote the transformation of building production methods. Summary of the invention

[0005] The object of the present invention is to provide an assembled bonded prestressed cross beam-column connection structure and a construction method thereof, so as to solve the problems raised by the background technology.

[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: an assembled bonded prestressed cross beam-column connection structure, comprising a prefabricated column, a composite steel rib beam, a superimposed T-beam, prestressed tendons and a negative bending moment resistant rib plate, a composite steel rib beam is arranged inside the upper end of the prefabricated column, a superimposed T-beam is arranged on the upper part of the composite steel rib beam, prestressed tendons are arranged inside the superimposed T-beam, and a negative bending moment resistant rib plate is fixed to the upper end of the superimposed T-beam by bolts, prestressed tendons are arranged vertically and horizontally at the connection node between the prefabricated column and the superimposed T-beam, and the node connection is completed by post-cast concrete at the beam-column joint.

[0007] Preferably, the prefabricated column and the composite steel rib beam are integrally formed in a PC factory. The composite steel rib beam is composed of an I-shaped steel beam and a supporting panel. The I-shaped steel beam and the supporting panel are an integrated structure and are pre-buried in the top of the prefabricated column during the production process of the prefabricated column in the PC factory. The width of the flange plate of the I-shaped steel beam is 80mm-100mm, the height of the web is 120mm-160mm, the thickness of the wing plate and the web is 20mm-35mm, the design width of the supporting panel is equal to the cross-sectional width of the web beam at the lower end of the composite T-beam, the thickness of the supporting panel is 25mm-40mm, the length of the overall composite steel rib beam extending out of the side of the prefabricated column is 550mm-800mm, and the top surface of the composite steel rib beam is flush with the top surface of the prefabricated column concrete; during the integrated forming process of the prefabricated column and the composite steel rib beam in the PC factory, the collision problem between the composite steel rib beam and the designed steel bars at the top of the prefabricated column is solved by reserving holes in the composite steel rib beam.

[0008] Preferably, the composite T-beam is prefabricated in a PC factory and consists of a wing beam part and a web beam part. The overall composite T-beam height is not less than 500 mm, the wing beam height of the prefabricated part is not less than 120 mm, and the height does not include the post-casting section. The wing beam width is not less than 600 mm, the web beam width is not less than 250 mm, and the web beam height is not less than 350 mm. Ordinary steel bars and prestressed bars are provided inside the composite T-beam, and the specific size is determined according to the structural force design.

[0009] Preferably, the composite T-beam is placed on the upper part of the composite steel rib beam, and the end of the composite T-beam is placed on the prefabricated column by at least 10 mm. The ordinary steel bars extending outward from the end of the composite T-beam are anchored in the post-cast section at the top of the prefabricated column, and the anchoring length is not less than 450 mm. In order to enhance the seismic performance of the beam-column node, each end of the ordinary steel bar extending outward of the composite T-beam is provided with an anchor plate, and the number is 100%; the lower part of the web beam and the end of the wing beam of the composite T-beam are provided with prestressed tendons, and the prestressed tendons can be bonded prestressed tendons. The prestressed tendon ducts inside the composite T-beam are designed and reserved in advance during the prefabrication production process of the composite T-beam. The layout of the prestressed tendons shall not collide with the ordinary steel bars inside the composite T-beam. If necessary, BIM technology software is used to assist in the design and PC factory component production.

[0010] Preferably, in order to improve the bearing capacity of negative bending moment at the beam-column joint, negative bending moment ribs are provided at the beam-column joint. The negative bending moment ribs are fixed to the top of the composite T-beam by bolts. The negative bending moment ribs are located in the composite layer of the composite T-beam. The cutting length of the negative bending moment ribs is not less than the side length of the prefabricated column in the same direction + 2000mm. They are arranged throughout the length. The negative bending moment ribs are composed of a web and enlarged section plates at both ends. The minimum size of the web and the enlarged section plates at both ends is not less than 12mm, which is determined according to the specific working conditions.

[0011] Preferably, the prefabricated columns and the composite steel rib beams integrally formed at their upper ends are divided into beam-column nodes with composite steel rib beams integrally formed on one side, beam-column nodes with composite steel rib beams integrally formed on both sides, beam-column nodes with composite steel rib beams integrally formed on three sides, and beam-column nodes with composite steel rib beams integrally formed on four sides according to the position relationship of the building structure; according to the force characteristics, the structure designs double cross nodes, adopts two types of beam-column node cross design and prestressed cross layout, and focuses on designing the negative bending moment effect at the beam-column nodes to improve the seismic performance of the nodes.

[0012] Preferably, in order to enhance the connection reliability between the composite T-beam and the prefabricated column and improve the efficiency of hoisting the composite T-beam into place, the composite steel rib beam is provided with bolt holes that are connected to the composite T-beam, and the diameter of the bolt hole is equal to the diameter of the bolt hole reserved inside the composite T-beam and is not less than 20 mm.

[0013] The present invention also provides a construction method for an assembled bonded prestressed cross beam-column connection structure, and the construction process comprises the following steps: PC component production, transportation, finished product protection---on-site measurement and layout, on-site hoisting of prefabricated columns---position verification of combined steel rib beams, sleeve grouting---hoisting of composite T-beams, pre-piercing of middle bolts---reinforcement treatment in beam-column nodes, laying of prestressed tendon channels and perforation of prestressed tendons---bolt perforation, installation of negative bending moment ribs---hoisting of composite plates, installation of aluminum molds at beam-column nodes---reinforcement binding of composite plates, acceptance of concealed works---integral pouring of concrete of beams, plates and columns, tensioning, anchoring and grouting of prestressed tendons and channel grouting---flow construction, and the above steps are repeated until all structural construction is completed.

[0014] Preferably, the specific technical solution is as follows:

[0015] Step S1: PC component production, transportation, and finished product protection

[0016] Firstly, the precast columns and composite T-beams were designed in depth according to the drawings, and the position relationship between the precast columns and the composite steel rib beams at their upper ends was assisted by BIM technology software. The collision relationship between the internal reinforcement of the precast columns and the composite steel rib beams was checked in particular, and the materials were accurately cut and prefabricated in an integrated manner. During the prefabrication of the composite T-beams, the height of the upper superimposed post-casting of the composite T-beams was ensured, and the reinforcement of the superimposed post-casting section met the reinforcement anchoring and force requirements of the beam-slab nodes. The relationship between the internal prestressed reinforcement holes of the composite T-beams and the designed reinforcement layout of the composite T-beams, as well as the prestressing of the bolt holes inside the composite T-beams, were checked in particular. In principle, ordinary steel bars should avoid prestressed bars without affecting the stress, so as not to affect the construction quality and bearing capacity; after the prefabricated columns, composite T-beams and other components are produced and prefabricated in the PC factory, they can be lifted when the concrete strength reaches more than 85% of the design strength, and can be loaded and transported only when it reaches 100% of the design strength. During transportation, the prefabricated columns and the integrated composite steel rib beams at their upper ends should be protected. The prefabricated components should not be deformed or damaged due to transportation, and the appearance quality problems such as affecting the lifting of the components should not occur, and the finished products should be well protected;

[0017] Step S2: On-site measurement and layout, on-site hoisting of prefabricated columns

[0018] After the prefabricated components arrive at the site, we organize special personnel to inspect and accept them. Components with unqualified appearance quality are not allowed to enter the site, and the quality is strictly controlled. After the prefabricated components arrive at the site, we organize the flow construction reasonably according to the on-site measurement schedule, hoist the prefabricated column grid in sections, and mechanically hoist each prefabricated column according to the prefabricated column position line and control line on the top surface of the foundation. The prefabricated columns are temporarily fixed in place with inclined adjustable steel supports, and the plane position and top elevation of the composite steel rib beams after each prefabricated column is in place are strictly checked. The on-site hoisting of the prefabricated columns adopts the "secondary placement" method, that is, the first First, adjust the installation elevation of each prefabricated column according to the elevation of the top surface of the base layer, accurately align the steel sleeve at the bottom of the prefabricated column with the vertical steel bar of the base layer, use the inclined adjustable steel support to initially fix the prefabricated column in place, and then check the top elevation of the composite steel rib beam formed by the prefabricated column one by one, and check the top elevation of each composite steel rib beam one by one, and control the error within 2mm. Finally, adjust the verticality of each prefabricated column, tighten the inclined steel support, and complete the installation of the prefabricated column; do a good job in protecting the composite steel rib beam throughout the process, set up special personnel for inspection and acceptance, and keep acceptance records;

[0019] Step S3: Check the position of the combined steel rib beam and grout the sleeve

[0020] The position of the composite steel rib beam directly affects the subsequent hoisting and positioning of the prefabricated composite T-beam. Due to the large volume of the prefabricated composite T-beam, it is difficult to adjust it after it is in place, which directly affects the overall schedule. Therefore, after the prefabricated columns in the construction section are accurately hoisted and positioned, the position relationship and elevation of the composite steel rib beams at each beam-column node are checked and adjusted, and grouting is immediately carried out after confirmation. For beam-column nodes with composite steel rib beams integrated on both sides, beam-column nodes with composite steel rib beams integrated on three sides, and beam-column nodes with composite steel rib beams integrated on four sides, the position relationship and top surface elevation of adjacent composite steel rib beams at the same node should also be checked during the on-site construction process. When the error is large, the position relationship of the prefabricated composite T-beam can be adjusted to integrate the hoisting error of the prefabricated column. The grouting of the steel sleeve at the bottom of the on-site prefabricated column adopts high-strength, low-shrinkage, and micro-expansion grouting material, which is mixed and used at the same time and poured at one time. A dedicated person is stationed on site to ensure the grouting quality of the sleeve at the bottom of each prefabricated column, and to do a good job in the acceptance and record of the hidden project of the steel sleeve grouting.

[0021] Step S4: Hoisting of the superimposed T-beam and pre-piercing of the middle bolts

[0022] In order to achieve efficient hoisting of the composite T-beam into place, the composite T-beam can be hoisted after each section of the composite steel rib beam is checked and found to be correct; the bottom of the web beam of the designed composite T-beam is pre-buried with a steel pad during the prefabrication production process of the PC factory. During the on-site hoisting, after the composite T-beam is finally in place, it is necessary to ensure that its end is at least 10mm above the end face of the prefabricated column. After verifying that the plane position and elevation of the composite T-beam are correct, the three-sided full welding method is used to connect and fix the steel pad at the bottom of the composite T-beam to the composite steel rib beam, so as to achieve the effect of no or less support for the lower part of the composite T-beam. The composite T-beam is fixed as soon as it is hoisted into place, which improves the hoisting efficiency and reduces Low construction cost; after the composite T-beam is hoisted in place and fixed, high-strength bolts are used to punch holes from the bottom of the composite steel rib beam, and all the middle bolts on the composite T-beam are threaded in sequence. The high-strength bolts on the composite steel rib beams on each side are designed to be no less than 3, which can improve the shear bearing capacity at the beam-column node. The high-strength bolts within the range of the composite steel rib beams at both ends are first inserted, and then the high-strength bolts in the middle section of the web beam on the composite T-beam are inserted. That is, the two sides are controlled first, and the bolt holes in the middle section of the web beam on the composite T-beam are not subject to hoisting errors. The bolt holes in the middle section of the web beam on the composite T-beam are evenly arranged, with a spacing of no more than 450mm and no less than 5 bolts;

[0023] Step S5: Steel bar processing in beam-column joints, prestressed bar channel layout and prestressed bar punching

[0024] After the composite T-beam is hoisted in place, the beam-column joint and the upper post-cast section of the composite T-beam can be processed; first, all the ordinary steel bars of the composite T-beam are effectively anchored into the beam-column joint, and the anchor length is not less than 35d, d is the diameter of the ordinary steel bars of the composite T-beam, and is not less than 800mm. When the anchor length of the ordinary steel bars cannot meet the design requirements, anchor plates can be set at the ends of the ordinary steel bars; the steel bars in the beam-column joint and the upper post-cast section of the composite T-beam should be arranged throughout the length, and the diameter of the main force bar should be not less than 30mm, and the requirements for the clear distance of the steel bars in the later concrete pouring should be met; for the arrangement requirements of the prestressed tendons, after the steel bars at the beam-column joint are installed, the prestressed tendons inside are perforated and the internal parts of the beam-column joints are Pre-embedded prestressed tendon ducts; the prestressed tendons inside the prefabricated composite T-beam are pierced from one end of the composite T-beam to the beam-column node by the traction method, and then the prestressed tendon duct inside the beam-column node is pierced through the composite T-beam at the other end, and the prestressed tendons are arranged crosswise to meet the linear trend of the prestressed tendons; the prestressed tendon ducts at the beam-column node are reliably pre-embedded with metal corrugated pipes, and the pre-embedded metal corrugated pipes inside the beam-column node should comply with the linear trend of the designed prestressed tendons. The metal corrugated pipes are fixed to the steel bars inside the beam-column node by additional stirrups, and the ends of the metal corrugated pipes are accurately connected with the reserved duct ports inside the composite T-beams on each side in the beam-column node, and reliably fixed, and the concealed project acceptance work is done well;

[0025] Step S6: Bolt holes and negative moment rib installation

[0026] After the prestressed tendons are laid, the high-strength bolts of the wing beam of the composite T-beam can be punched. The high-strength bolts on the wing beams on both sides are arranged in a "staggered wave" style and asymmetrically set to enhance the shear resistance of the composite T-beam. Then, the anti-negative bending moment ribs in the upper post-casting section of the composite T-beam are installed, and the installation holes on the anti-negative bending moment ribs are penetrated one by one with high-strength bolts for reliable fixation; at the beam-column node and within 1000mm on both sides, the anti-negative bending moment ribs should be set throughout the length, and incomplete installation phenomena such as splicing and welding of the anti-negative bending moment ribs shall not occur within this range, so as not to affect the overall structural stress performance. There shall be no less than 3 anti-negative bending moment ribs in the same direction, and their installation shall not affect the extension of the steel bars at the top of the prefabricated column and the subsequent concrete pouring process, and the process acceptance and record work shall be done well;

[0027] Step S7: Hoisting of composite slabs and installation of aluminum formwork at beam-column joints

[0028] The design adopts the integrated integral superposition cast-in-place forming of beams, plates and columns. On the basis of completing the above-mentioned process, the superimposed plates are hoisted in sections, modules and sections. The ends of the superimposed plates are fixed with high-strength bolts in the upper superimposed layer of the superimposed T-beam or the post-casting section by locally pre-embedded connecting steel plates. The steel bars at the ends of the superimposed plates in other parts extend into the superimposed layer of the superimposed T-beam. Additional steel bars are provided at the junction of the superimposed T-beam and the superimposed plates. The cutting length of the additional steel bars is not less than 1200mm, the diameter is not less than 10mm, and the spacing is not more than 100mm. The additional steel bars are placed on the negative moment ribs in the superimposed layer, and the additional steel bars should be spot welded and fixed to the negative moment ribs one by one. In order to meet the subsequent concrete pouring process, aluminum molds are used for rapid assembly at the beam-column nodes. When the aluminum molds are installed, elastic sealing strips are attached to the contact surfaces with the prefabricated columns and superimposed beams. The aluminum molds are tightened and fixed with the pre-embedded internal threads on the superimposed T-beams and prefabricated columns by screws to achieve the purpose of rapid installation.

[0029] Step S8: Composite slab reinforcement binding and concealed engineering acceptance

[0030] According to the construction plan, double-layer bidirectional steel mesh is used for the on-site hoisting construction of the composite slab. After the composite slab is hoisted into place, after the steel bar connection at the node between the composite slab and the composite T-beam is handled, the upper steel mesh is tied to the upper truss bar of the composite slab. The diameter of the distributed steel bars of the upper steel mesh is not less than 10mm, and the spacing of the distributed steel bars does not exceed 150mm. The distributed steel bars at the composite slab and the composite T-beam should be laid throughout the length and appropriately dense, with a spacing of no more than 100mm. During the on-site construction process, when the bonded prestressing technology is adopted, when the composite slab steel mesh is tied, the grouting holes and overflow holes should be reserved on the metal corrugated pipe installed in the post-casting section at the beam-column node, and the overall steel bar concealment project acceptance work should be done well.

[0031] Step S9: Concrete pouring of beams, slabs and columns, prestressing, anchoring and grouting of holes

[0032] After all the above processes are completed and accepted, the concrete of beams, slabs and columns can be poured as a whole. No construction joints shall be left at the beam-column nodes. The concrete strength shall not be less than C30. The concrete pouring at the nodes of precast columns and superimposed T-beams, and superimposed T-beams and superimposed slabs shall be vibrated to ensure the quality of concrete pouring at the nodes. The curing time shall not be less than 7 days. For the tensioning and anchoring of prestressed tendons on site, the tensioning and anchoring of prestressed tendons shall be carried out only after the construction of all structures of the layer is completed and the concrete strength reaches 100% of the design strength. 1.03σcom over-tensioning, symmetrical tensioning, and timely grouting are adopted. The prestressed tendons are anchored at the end or bottom of the superimposed T. The overall prestressed tendon tensioning is symmetrically completed from the middle of the structure to both ends. The tensioning and anchoring of the prestressed tendons are completed symmetrically. The tensioning and anchoring of the prestressed tendons are ensured to be dense as the tensioning and anchoring are completed. A dedicated person is assigned to supervise the process and good acceptance records are kept.

[0033] Step S10: Flow construction, repeating steps 1 to 9 until all structural construction is completed

[0034] On-site hoisting construction, the hoisting connection of prefabricated columns and composite T-beams has become the focus of the technical solution. The seismic design and construction of beam-column nodes are a significant manifestation of the technical solution's structural innovation and process optimization. For engineering projects with beam-column spans exceeding 12m, special scheme certification should be carried out to ensure the operational safety of the hoisting project. According to the technical solution, a flow construction organization form is adopted, and the above process steps 1 to 9 are repeated until the hoisting construction of the entire structure is completed, and finally the project acceptance and material archiving are carried out.

[0035] Compared with the prior art, the beneficial effects of the present invention are as follows: the technical scheme of the present invention is based on the principle of "integrated prefabricated column design of combined steel rib beams, reinforced load-bearing of composite T-beams, staggered wave-type high-strength bolts for shear resistance, node connection of negative bending moment ribs, cross-arrangement of longitudinal and transverse prestressed tendons, and one-time forming of post-poured concrete". Compared with traditional construction methods, the seismic performance is significantly improved, the construction period is saved by more than 65%, the construction cost is reduced by about 40%, the requirements of green construction technology standards are met, the research and development and application of new technologies are strengthened, and favorable technical support is provided for the high-quality development of my country's prefabricated construction technology field. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a structural schematic diagram of a prefabricated column with a combined steel rib beam integrally formed on one side of the connection structure of the present invention;

[0037] Figure 2 is a schematic diagram of a combined steel rib beam of a connection structure of the present invention;

[0038] Figure 3 is a schematic diagram of a composite T-beam of a connection structure of the present invention;

[0039] Figure 4 It is a schematic diagram of the installation of the negative moment resisting rib plate of the connection structure of the present invention;

[0040] Figure 5 It is a structural schematic diagram of a prefabricated column formed integrally with composite steel rib beams attached to three sides of the connection structure of the present invention;

[0041] Figure 6 It is a structural schematic diagram of prefabricated columns formed integrally with combined steel rib beams attached to four sides of the connection structure of the present invention;

[0042] Figure 7 It is a position relationship diagram of the composite T-beam and the combined steel rib beam of the connection structure of the present invention;

[0043] Figure 8 It is a structural schematic diagram of an embodiment of a prefabricated column integrally formed with composite steel rib beams attached to both sides of the connection structure of the present invention;

[0044] Fig. 9 It is a structural schematic diagram of an embodiment of a prefabricated column integrally formed with composite steel rib beams attached to both sides of the connection structure of the present invention;

[0045] Fig.10 It is a construction process flow chart of the connection structure of the present invention;

[0046] Figure numerals: 1-prefabricated column, 2-combined steel rib beam, 21-support panel, 22-I-beam, 3-composite T-beam, 31-wing beam, 32-web beam, 33-prestressed tendons, 4-anti-negative bending rib plate, 5-bolt. DETAILED DESCRIPTION

[0047] See also Figures 1 to 9 The embodiment of the present invention discloses an assembled bonded prestressed cross beam-column connection structure and a construction method thereof, wherein the connection structure comprises a prefabricated column 1, a composite steel rib beam 2, a composite T-beam 3, a prestressed tendon 33 and a negative moment resisting rib plate 4, see Figure 1 , a composite steel rib beam 2 is provided inside the upper end of the prefabricated column 1; Figure 7 , a composite steel rib beam 2 is provided with a composite T beam 3 on the upper part; Figure 3 , the composite T-beam 3 is provided with prestressed tendons 33 inside; Figure 4 The upper end of the composite T-beam 3 is fixed with a negative bending moment rib 4 by bolts 5; the prestressed tendons 33 are arranged crosswise at the connection node between the prefabricated column 1 and the composite T-beam 3, and the node connection is completed by post-cast concrete at the butt joint of the beam and column.

[0048] The composite T-beam 3 is prefabricated in the PC factory and consists of a spar 31 and a web 32. The overall composite T-beam 3 is not less than 500mm high, the spar 31 of the prefabricated part is not less than 120mm high (excluding the post-casting section), the spar 31 is not less than 600mm wide, the web 32 is not less than 250mm wide, and the web 32 is not less than 350mm high. Common steel bars and prestressed bars 33 are provided inside the composite T-beam 3. Figure 3 The red part in the middle is ordinary steel bar, and the specific sizes of the two are determined according to the structural force design.

[0049] The prefabricated column 1 and the composite steel rib beam 2 are integrally formed in the PC factory. The composite steel rib beam 2 is composed of an I-shaped steel beam 21 and a supporting panel 22. The I-shaped steel beam 21 and the supporting panel 22 are an integrated structure and are embedded in the top of the prefabricated column 1 during the production process of the prefabricated column 1 in the PC factory. The flange width of the I-shaped steel beam 21 is 80mm~100mm, the web height is 120mm~160mm, the flange and web thickness is 20mm~35mm, the design width of the supporting panel 22 is equal to the cross-sectional width of the web beam 32 at the lower end of the composite T-beam 3, the thickness of the supporting panel 22 is 25mm~40mm, the overall composite steel rib beam 2 extends out of the side of the prefabricated column 1 by 550mm~800mm, and the top surface of the composite steel rib beam 2 is flush with the concrete top surface of the prefabricated column 1. During the integrated forming process of the precast column 1 and the composite steel rib beam 2 in the PC factory, holes are reserved on the composite steel rib beam 2 to solve the collision problem with the designed steel bars at the top of the precast column 1.

[0050] The composite T-beam 3 is placed on the upper part of the composite steel rib beam 2, and the end of the composite T-beam 3 is placed on the prefabricated column 1 for at least 10mm. The ordinary steel bars extending outward from the end of the composite T-beam 3 are anchored in the post-casting section at the top of the prefabricated column 1, and the anchoring length is not less than 450mm. In order to strengthen the seismic performance of the beam-column node, each end of the ordinary steel bars extending outward from the composite T-beam 3 is provided with an anchor plate, and the number is set 100%. The lower part of the web beam 32 and the end of the wing beam 31 of the composite T-beam 3 are provided with prestressed tendons 33, and the prestressed tendons 33 can be bonded prestressed tendons. The prestressed tendon duct inside the composite T-beam 3 is reserved in advance during the prefabrication production process of the composite T-beam 3. The layout of the prestressed tendons 33 shall not collide with the ordinary steel bars inside the composite T-beam 3. If necessary, BIM technology software is used to assist in design and PC factory component production.

[0051] In order to improve the negative moment bearing capacity at the beam-column joint, a negative moment rib 4 is provided at the beam-column joint. The negative moment rib 4 is fixed to the top of the composite T-beam 3 by bolts 5. The negative moment rib 4 is located in the composite layer of the composite T-beam 3. The cutting length of the negative moment rib 4 is not less than the side length of the prefabricated column 1 in the same direction + 2000mm. It is arranged throughout the length. The negative moment rib 4 consists of a web and expanded section plates at both ends. The minimum size of the web and the expanded section plates at both ends is not less than 12mm, which is determined according to the specific working conditions.

[0052] The prefabricated column 1 and the composite steel rib beam 2 formed integrally at the upper end thereof are divided into the following according to the position relationship of the building structure: Figure 1 The beam-column node shown in the figure is formed by integrating a composite steel rib beam on one side. Figure 8 and Fig. 9 The beam-column node shown has a composite steel rib beam integrated on both sides. Figure 5 The beam-column joint with three sides having composite steel rib beams integrally formed is shown. Figure 6The four sides of the beam-column node are formed by integrated composite steel rib beams. According to the force characteristics, the structure is designed with double cross nodes, using two types of cross design of beam-column nodes and cross layout of prestressed steel. The design focuses on the effect of negative bending moment at the beam-column node to improve the seismic performance of the node.

[0053] In order to strengthen the connection reliability between the composite T-beam 3 and the prefabricated column 1 and improve the efficiency of hoisting the composite T-beam 3, bolt holes for docking with the composite T-beam 3 are provided on the composite steel rib beams 2 on each side. The diameter of the bolt hole is equal to the diameter of the bolt hole reserved inside the composite T-beam 3 and is not less than 20 mm.

[0054] The construction process of the above-mentioned connection structure is as follows: PC component production, transportation, finished product protection---on-site measurement and layout, on-site hoisting of prefabricated columns---combined steel rib beam position verification, sleeve grouting---composite T-beam hoisting, pre-piercing of middle bolts---reinforcement treatment in beam-column nodes, layout of prestressed tendon ducts and perforation of prestressed tendons---bolt perforation, installation of negative bending moment ribs---composite slab hoisting, installation of aluminum molds at beam-column nodes---composite slab reinforcement binding, concealed project acceptance---integral pouring of beam, slab and column concrete, prestressed tendon tensioning, anchoring and duct grouting---flow construction, and the above steps are repeated until the entire structural construction is completed.

[0055] Based on the entire construction process, the specific technical solution of a construction method for a prefabricated bonded prestressed cross beam-column connection structure is as follows:

[0056] Step S1: PC component production, transportation, and finished product protection:

[0057] First, the prefabricated columns and composite T-beams are designed in depth according to the drawings, and the position relationship between the prefabricated columns and the composite steel rib beams at their upper ends is assisted by BIM technology software. The collision relationship between the internal steel bars of the prefabricated columns and the composite steel rib beams is checked, and the materials are accurately cut and prefabricated in an integrated manner. During the prefabrication of the composite T-beam, the height of the upper superimposed post-casting of the composite T-beam is ensured, and the superimposed post-casting section steel bars meet the requirements for anchoring and force of the beam-slab nodes. The relationship between the internal prestressed tendon channels of the composite T-beam and the designed steel bar layout of the composite T-beam, as well as the reservation of the bolt holes inside the composite T-beam, are checked. In principle, ordinary steel bars should avoid prestressed tendons without affecting the force, so as not to affect the construction quality and bearing capacity. After prefabricated columns, composite T-beams and other components are prefabricated in the PC factory, they can be lifted when their concrete strength reaches 85% of the design strength, and can be loaded and transported only when it reaches 100% of the design strength. During transportation, the prefabricated columns and the integrated composite steel rib beams at their upper ends should be protected. The prefabricated components must not be deformed, damaged, or have appearance quality problems that affect the lifting of the components due to transportation reasons, and the finished products must be well protected.

[0058] Step S2: On-site measurement and layout, on-site hoisting of prefabricated columns:

[0059] After the prefabricated components arrive at the site, we organize special personnel to inspect and accept them. Components with unqualified appearance quality are not allowed to enter the site, and the quality is strictly controlled. After the prefabricated components arrive at the site, we organize the flow construction reasonably according to the on-site measurement schedule, hoist the prefabricated column grid in sections, and mechanically hoist each prefabricated column according to the prefabricated column position line and control line on the top surface of the foundation. Use inclined adjustable steel supports to temporarily fix the prefabricated columns in place, and strictly check the plane position and top elevation of the composite steel rib beam after each prefabricated column is in place. The on-site hoisting and installation of prefabricated columns adopts the "secondary installation" method, that is, the hoisting and installation elevation of each prefabricated column is adjusted according to the elevation of the top surface of the base layer for the first time, the steel sleeve at the bottom of the prefabricated column is accurately aligned with the vertical steel bars of the base layer, and the prefabricated column is initially fixed with an inclined adjustable steel support. Then, the elevation of the top surface of the composite steel rib beam formed by the prefabricated column is reviewed, and the elevation of the top surface of each composite steel rib beam is reviewed one by one, and the error is controlled within 2mm. Finally, the verticality of each prefabricated column is adjusted, and the inclined steel support is tightened to complete the hoisting of the prefabricated column. The composite steel rib beam is well protected throughout the process, and a dedicated person is assigned to inspect and accept it, and the acceptance record is kept.

[0060] Step S3: Check the position of the combined steel rib beam and grout the sleeve:

[0061] The position of the composite steel rib beam directly affects the subsequent hoisting and placement of the prefabricated composite T beam. Due to the large volume of the prefabricated composite T beam, it is difficult to adjust it after it is in place, which directly affects the overall schedule. Therefore, after the prefabricated columns in the construction section are accurately hoisted and placed, the position relationship and elevation of the composite steel rib beams at each beam-column node are checked and adjusted, and grouting is performed immediately after confirmation. For beam-column nodes with composite steel rib beams integrated on both sides, beam-column nodes with composite steel rib beams integrated on three sides, and beam-column nodes with composite steel rib beams integrated on four sides, the position relationship and top elevation of adjacent composite steel rib beams at the same node should also be checked during the on-site construction process. When the error is large, the position relationship of the prefabricated composite T beam can be adjusted to integrate the hoisting error of the prefabricated column. The steel sleeve grouting at the bottom of the on-site prefabricated column uses high-strength, low-shrinkage, and micro-expansion grouting materials, which are mixed and used at the same time and poured at one time. A special person is stationed on site to ensure the quality of the grouting of the sleeves at the bottom of each prefabricated column, and to do a good job in the acceptance and record of the hidden engineering of the steel sleeve grouting.

[0062] Step S4: Hoisting of the superimposed T-beam and pre-piercing of the middle bolts:

[0063] In order to achieve efficient hoisting of the composite T-beam, the composite T-beam can be hoisted after each section of the composite steel rib beam is checked. The bottom of the web beam of the designed composite T-beam is pre-buried with a steel pad during the prefabrication production process of the PC factory. During the on-site hoisting process, after the composite T-beam is finally in place, it is necessary to ensure that its end is at least 10mm from the end face of the prefabricated column. After verifying the plane position and elevation of the composite T-beam in place, the three-sided full welding method is used to connect and fix the steel pad at the bottom of the composite T-beam to the composite steel rib beam, so as to achieve the effect of no or less support for the lower part of the composite T-beam. The composite T-beam is fixed as soon as it is hoisted into place, which improves the hoisting efficiency and reduces the construction cost. After the composite T-beam is hoisted into place and fixed, high-strength bolts are used to penetrate holes from the bottom of the composite steel rib beam, and all the middle bolts on the composite T-beam are penetrated in turn. The number of high-strength bolts on the composite steel rib beams on each side is designed to be no less than 3, which can improve the shear bearing capacity at the beam-column node. The method of "first penetrate the high-strength bolts within the range of the composite steel rib beams at both ends, and then penetrate the high-strength bolts in the middle section of the web beam on the composite T-beam" is adopted, that is, control the two sides first, and the bolt penetration holes in the middle section of the web beam on the composite T-beam are not subject to hoisting errors, and the bolt penetration holes in the middle section of the web beam on the composite T-beam are evenly arranged, with a spacing of no more than 450mm and no less than 5 bolts.

[0064] Step S5: Processing of steel bars in beam-column joints, layout of prestressed tendon channels and perforation of prestressed tendons:

[0065] After the composite T-beam is hoisted in place, the beam-column joint and the upper post-cast section of the composite T-beam can be processed. First, all the ordinary steel bars of the composite T-beam are effectively anchored into the beam-column joint. The anchor length is not less than 35d (d is the diameter of the ordinary steel bars of the composite T-beam) and not less than 800mm. When the anchor length of the ordinary steel bars cannot meet the design requirements, anchor plates can be set at the ends of the ordinary steel bars. The steel bars in the beam-column joint and the upper post-cast section of the composite T-beam should be arranged throughout the length, and the diameter of the main force-bearing bars should not be less than 30mm, and the requirements for the clear distance of steel bars in the later concrete pouring should be met. For the arrangement requirements of prestressed tendons, after the installation of the steel bars at the beam-column joint, the prestressed tendons inside are perforated and the prestressed tendon holes inside the beam-column joint are pre-embedded. The prestressed tendons inside the prefabricated composite T-beam are pierced from one end of the composite T-beam to the beam-column node by the traction method, and then the prestressed tendon channel inside the beam-column node is passed through the composite T-beam at the other end to pierce, and the prestressed tendons are arranged crosswise to meet the linear direction of the prestressed tendons. The prestressed tendon channel at the beam-column node is reliably pre-embedded with a metal corrugated pipe. The pre-embedding of the metal corrugated pipe inside the beam-column node should comply with the linear direction of the designed prestressed tendons. The metal corrugated pipe is fixed to the steel bars inside the beam-column node by additional stirrups, etc. The end of the metal corrugated pipe is accurately connected with the reserved channel port inside the composite T-beam on each side in the beam-column node, and reliably fixed, and the concealed project acceptance work is done well.

[0066] Step S6: Bolt punching and negative moment rib installation:

[0067] After the prestressed tendons are laid, the high-strength bolts of the wing beam of the composite T-beam can be punched. The high-strength bolts on the wing beams on both sides are arranged in a "staggered wave" style, and are set asymmetrically to strengthen the shear resistance of the composite T-beam. Then, the anti-negative bending moment ribs in the upper post-casting section of the composite T-beam are installed, and each installation hole on the anti-negative bending moment rib is penetrated by each high-strength bolt one by one for reliable fixation. At the beam-column node and within 1000mm on both sides, the anti-negative bending moment ribs should be set throughout the length. Incomplete installation of the anti-negative bending moment ribs such as splicing and welding shall not occur within this range, so as not to affect the overall structural force performance. There shall be no less than 3 anti-negative bending moment ribs in the same direction, and their installation shall not affect the extension of the steel bars at the top of the prefabricated column and the later concrete pouring process. The process acceptance and record work shall be done well.

[0068] Step S7: Hoisting of composite slabs and installation of aluminum formwork at beam-column joints:

[0069] The design adopts the integrated cast-in-place forming of beams, plates and columns. On the basis of completing the above-mentioned process, the superimposed plates are hoisted in sections, modules and sections. The ends of the superimposed plates are fixed with high-strength bolts in the superimposed layer of the superimposed T-beam or the post-casting section in the form of locally embedded connecting steel plates. The steel bars at the ends of the superimposed plates in other parts extend into the superimposed layer of the superimposed T-beam. Additional steel bars are set at the intersection of the superimposed T-beam and the superimposed plates. The length of the additional steel bars is not less than 1200mm, the diameter is not less than 10mm, and the spacing is not more than 100mm. The additional steel bars are placed on the negative moment ribs in the superimposed layer, and the additional steel bars should be spot welded and fixed to the negative moment ribs one by one. In order to meet the subsequent concrete pouring process, aluminum molds are used for rapid assembly at the beam-column nodes. When the aluminum molds are installed, elastic sealing strips are attached to the contact surfaces with the prefabricated columns and superimposed beams. The aluminum molds are screwed and fixed with the embedded internal threads on the superimposed T-beams and prefabricated columns to achieve the purpose of rapid installation.

[0070] Step S8: Composite slab reinforcement binding and concealed engineering acceptance:

[0071] According to the construction plan, the on-site composite slab hoisting construction adopts double-layer bidirectional steel mesh. After the composite slab is hoisted into place, after the steel bar connection at the joint of the composite slab and the composite T-beam is handled, the upper steel mesh is tied to the upper truss bar of the composite slab. The diameter of the distributed steel bars of the upper steel mesh is not less than 10mm, and the spacing of the distributed steel bars does not exceed 150mm. The distributed steel bars at the composite slab and the composite T-beam should be laid throughout the length and appropriately encrypted, with the encrypted spacing not exceeding 100mm. During the on-site construction process, when the bonded prestressing technical solution is adopted, when the composite slab steel mesh is tied, the grouting holes and overflow holes should be reserved on the metal corrugated pipe installed in the post-casting section at the beam-column joint, and the overall steel bar concealment project acceptance work should be done well.

[0072] Step S9: integral pouring of concrete for beams, slabs and columns, tensioning and anchoring of prestressed tendons and grouting of holes:

[0073] After all the above processes are completed and accepted, the concrete of beams, slabs and columns can be poured as a whole. No construction joints shall be left at the beam-column nodes. The concrete strength shall not be less than C30. The concrete pouring at the nodes between precast columns and superimposed T beams, and the nodes between superimposed T beams and superimposed slabs shall be vibrated to ensure the quality of the node concrete pouring. The curing time shall not be less than 7 days. For the tensioning and anchoring of prestressed tendons on site, the tensioning and anchoring of prestressed tendons shall be carried out only after the construction of all structures of the layer is completed and the concrete strength reaches 100% of the design strength. 1.03σcom over-tensioning, symmetrical tensioning, and timely grouting are adopted. The prestressed tendons are anchored at the end or bottom of the superimposed T. The tensioning and anchoring of the overall prestressed tendons are completed symmetrically from the middle of the structure to both ends. The tensioning and anchoring of the prestressed tendons are completed symmetrically. The tensioning and anchoring of the prestressed tendons are ensured to be dense. A dedicated person is assigned to supervise the process and good acceptance records are kept.

[0074] Step S10: Flow construction, repeating steps 1 to 9 until all structural construction is completed:

[0075] On-site hoisting construction, the hoisting connection of prefabricated columns and composite T-beams has become the focus of the technical solution. The seismic design and construction of beam-column nodes are a significant manifestation of the technical solution's structural innovation and process optimization. For engineering projects with beam-column spans exceeding 12m, special scheme certification should be carried out to ensure the operational safety of the hoisting project. According to the technical solution, the flow construction organization form is adopted, and the above process steps 1 to 9 are repeated until the hoisting construction of the entire structure is completed, and finally the project acceptance and material filing are carried out.

[0076] In summary, the present invention is based on the principles of "combined steel rib beam integrated prefabricated column design, composite T-beam enhanced load-bearing, staggered wave-type high-strength bolts for shear resistance, node connection of negative bending moment ribs, cross-arrangement of longitudinal and transverse prestressed tendons, and one-time forming of post-poured concrete". Compared with traditional construction methods, the seismic performance is significantly improved, the construction period is saved by more than 65%, the construction cost is reduced by about 40%, the requirements of green construction technology standards are met, the research and development and application of new technologies are strengthened, and favorable technical support is provided for the high-quality development of my country's prefabricated construction technology field.

[0077] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An assembled bonded prestressed cross beam-column connection structure, characterized in that: It includes precast columns, composite steel rib beams, superimposed T-beams, prestressed tendons and negative moment resisting ribs. A composite steel rib beam is arranged inside the upper end of the precast column, a superimposed T-beam is arranged on the upper part of the composite steel rib beam, prestressed tendons are arranged inside the superimposed T-beam, and negative moment resisting ribs are fixed at the upper end of the superimposed T-beam by bolts. Prestressed tendons are arranged vertically and horizontally at the connection nodes of the precast column and the superimposed T-beam, and the node connection is completed by post-cast concrete at the beam-column joint.

2. The connection structure according to claim 1, characterized in that: The prefabricated column and the composite steel rib beam are formed in an integrated manner in the PC factory. The composite steel rib beam is composed of an I-shaped steel beam and a supporting panel. The I-shaped steel beam and the supporting panel are an integrated structure and are embedded in the top of the prefabricated column during the production process of the prefabricated column in the PC factory. The width of the flange plate of the I-shaped steel beam is 80mm~100mm, the height of the web is 120mm~160mm, the thickness of the flange and the web is 20mm~35mm, the design width of the supporting panel is equal to the cross-sectional width of the web beam at the lower end of the composite T-beam, the thickness of the supporting panel is 25mm~40mm, the length of the overall composite steel rib beam extending out of the side of the prefabricated column is 550mm~800mm, and the top surface of the composite steel rib beam is flush with the top surface of the prefabricated column concrete; during the integrated forming process of the prefabricated column and the composite steel rib beam in the PC factory, the collision problem between the composite steel rib beam and the designed steel bars on the top of the prefabricated column is solved by reserving holes on the composite steel rib beam.

3. The connection structure according to claim 1, characterized in that: The composite T-beam is prefabricated in the PC factory and consists of a wing beam part and a web beam part. The overall composite T-beam height is not less than 500mm, and the wing beam height of the prefabricated part is not less than 120mm, which does not include the post-casting section. The wing beam width is not less than 600mm, the web beam width is not less than 250mm, and the web beam height is not less than 350mm. Ordinary steel bars and prestressed tendons are provided inside the composite T-beam, and the specific size is determined according to the structural force design.

4. The connection structure according to claim 3, characterized in that: The composite T-beam is placed on the upper part of the composite steel rib beam, and the end of the composite T-beam is placed on the prefabricated column for at least 10mm. The ordinary steel bars extending from the end of the composite T-beam are anchored in the post-cast section at the top of the prefabricated column, and the anchoring length is not less than 450mm. In order to enhance the seismic performance of the beam-column node, each end of the ordinary steel bar extending outward of the composite T-beam is provided with an anchor plate, and the number is 100% set; the lower part of the middle web beam and the end of the wing beam of the composite T-beam are provided with prestressed tendons, and the prestressed tendons can be bonded prestressed tendons. The prestressed tendon duct inside the composite T-beam is reserved in advance during the prefabrication production process of the composite T-beam. The layout of the prestressed tendons shall not collide with the ordinary steel bars inside the composite T-beam. If necessary, BIM technology software is used to assist in the design and PC factory component production.

5. The connection structure according to claim 1, characterized in that: In order to improve the negative moment bearing capacity at the beam-column joint, negative moment ribs are provided at the beam-column joint. The negative moment ribs are fixed to the top of the composite T-beam by bolts. The negative moment ribs are located in the composite layer of the composite T-beam. The cutting length of the negative moment ribs shall not be less than the side length of the prefabricated column in the same direction + 2000mm. They are arranged throughout the length. The negative moment ribs are composed of a web and expanded section plates at both ends. The minimum size of the web and the expanded section plates at both ends shall not be less than 12mm, which is determined according to the specific working conditions.

6. The connection structure according to claim 1, characterized in that: Prefabricated columns and their upper integrated composite steel rib beams are divided into beam-column nodes with integrated composite steel rib beams on one side, beam-column nodes with integrated composite steel rib beams on both sides, beam-column nodes with integrated composite steel rib beams on three sides and beam-column nodes with integrated composite steel rib beams on four sides according to the position relationship of the building structure. According to the force characteristics, the structure is designed with double cross nodes, and two types of beam-column node cross design and prestressed cross layout are adopted. The focus is on designing the negative bending moment effect at the beam-column node to improve the seismic performance of the node.

7. The connection structure according to claim 1, characterized in that: In order to strengthen the connection reliability between the composite T-beam and the prefabricated column and improve the efficiency of the lifting and installation of the composite T-beam, bolt holes that are connected to the composite T-beam are provided on the composite steel rib beam. The diameter of the bolt hole is equal to the diameter of the bolt hole reserved inside the composite T-beam and is not less than 20mm.

8. A construction method for an assembled bonded prestressed cross beam-column connection structure, characterized in that: The construction process is as follows: PC component production, transportation, and finished product protection---on-site measurement and layout, on-site hoisting of prefabricated columns---combined steel rib beam position verification, sleeve grouting---composite T-beam hoisting, pre-piercing of middle bolts---reinforcement treatment in beam-column nodes, layout of prestressed tendon ducts and perforation of prestressed tendons---bolt perforation, installation of negative bending moment ribs---composite slab hoisting, installation of aluminum molds at beam-column nodes---composite slab reinforcement binding, concealed project acceptance---integral pouring of beam, slab, and column concrete, prestressing, anchoring, and duct grouting of prestressed tendons---flow construction, and the above steps are repeated until the entire structural construction is completed.

9. The construction method according to claim 8, characterized in that: The specific technical solutions are as follows: Step S1: PC component production, transportation, and finished product protection Firstly, the precast columns and composite T-beams were designed in depth according to the drawings, and the position relationship between the precast columns and the composite steel rib beams at their upper ends was assisted by BIM technology software. The collision relationship between the internal reinforcement of the precast columns and the composite steel rib beams was checked in particular, and the materials were accurately cut and prefabricated in an integrated manner. During the prefabrication of the composite T-beams, the height of the upper superimposed post-casting of the composite T-beams was ensured, and the reinforcement of the superimposed post-casting section met the reinforcement anchoring and force requirements of the beam-slab nodes. The relationship between the internal prestressed reinforcement holes of the composite T-beams and the designed reinforcement layout of the composite T-beams, as well as the prestressing of the bolt holes inside the composite T-beams, were checked in particular. In principle, ordinary steel bars should avoid prestressed bars without affecting the stress, so as not to affect the construction quality and bearing capacity; after the prefabricated columns, composite T-beams and other components are produced and prefabricated in the PC factory, they can be lifted when the concrete strength reaches more than 85% of the design strength, and can be loaded and transported only when it reaches 100% of the design strength. During transportation, the prefabricated columns and the integrated composite steel rib beams at their upper ends should be protected. The prefabricated components should not be deformed or damaged due to transportation, and the appearance quality problems such as affecting the lifting of the components should not occur, and the finished products should be well protected; Step S2: On-site measurement and layout, on-site hoisting of prefabricated columns After the prefabricated components arrive at the site, we organize special personnel to inspect and accept them. Components with unqualified appearance quality are not allowed to enter the site, and the quality is strictly controlled. After the prefabricated components arrive at the site, we organize the flow construction reasonably according to the on-site measurement schedule, hoist the prefabricated column grid in sections, and mechanically hoist each prefabricated column according to the prefabricated column position line and control line on the top surface of the foundation. Use inclined adjustable steel supports to temporarily fix the prefabricated columns in place, and strictly check the plane position and top elevation of the composite steel rib beam after each prefabricated column is in place. The on-site hoisting of the prefabricated column adopts the "secondary placement" method, that is, the first First, adjust the installation elevation of each prefabricated column according to the elevation of the top surface of the base layer, accurately align the steel sleeve at the bottom of the prefabricated column with the vertical steel bar of the base layer, use the inclined adjustable steel support to initially fix the prefabricated column in place, and then check the top elevation of the composite steel rib beam formed by the prefabricated column one by one, and check the top elevation of each composite steel rib beam one by one, and control the error within 2mm. Finally, adjust the verticality of each prefabricated column, tighten the inclined steel support, and complete the installation of the prefabricated column; do a good job in protecting the composite steel rib beam throughout the process, set up special personnel for inspection and acceptance, and keep acceptance records; Step S3: Check the position of the combined steel rib beam and grout the sleeve The position of the composite steel rib beam directly affects the subsequent hoisting and positioning of the prefabricated composite T-beam. Due to the large volume of the prefabricated composite T-beam, it is difficult to adjust it after it is in place, which directly affects the overall schedule. Therefore, after the prefabricated columns in the construction section are accurately hoisted and positioned, the position relationship and elevation of the composite steel rib beams at each beam-column node are checked and adjusted, and grouting is immediately carried out after confirmation. For beam-column nodes with composite steel rib beams integrated on both sides, beam-column nodes with composite steel rib beams integrated on three sides, and beam-column nodes with composite steel rib beams integrated on four sides, the position relationship and top surface elevation of adjacent composite steel rib beams at the same node should also be checked during the on-site construction process. When the error is large, the position relationship of the prefabricated composite T-beam can be adjusted to integrate the hoisting error of the prefabricated column. The grouting of the steel sleeve at the bottom of the on-site prefabricated column adopts high-strength, low-shrinkage, and micro-expansion grouting material, which is mixed and used at the same time and poured at one time. A dedicated person is stationed on site to ensure the grouting quality of the sleeve at the bottom of each prefabricated column, and to do a good job in the acceptance and record of the hidden project of the steel sleeve grouting. Step S4: Hoisting of the superimposed T-beam and pre-piercing of the middle bolts In order to achieve efficient hoisting of the composite T-beam into place, the composite T-beam can be hoisted after each section of the composite steel rib beam is checked and found to be correct; the bottom of the web beam of the designed composite T-beam is pre-buried with a steel pad during the prefabrication production process of the PC factory. During the on-site hoisting, after the composite T-beam is finally in place, it is necessary to ensure that its end is at least 10mm above the end face of the prefabricated column. After verifying that the plane position and elevation of the composite T-beam are correct, the three-sided full welding method is used to connect and fix the steel pad at the bottom of the composite T-beam to the composite steel rib beam, so as to achieve the effect of no or less support for the lower part of the composite T-beam. The composite T-beam is fixed as soon as it is hoisted into place, which improves the hoisting efficiency and reduces Low construction cost; after the composite T-beam is hoisted in place and fixed, high-strength bolts are used to punch holes from the bottom of the composite steel rib beam, and all the middle bolts on the composite T-beam are inserted in sequence. The high-strength bolts on the composite steel rib beams on each side are designed to be no less than 3, which can improve the shear bearing capacity at the beam-column node. The high-strength bolts within the range of the composite steel rib beams at both ends are first inserted, and then the high-strength bolts in the middle section of the web beam on the composite T-beam are inserted. That is, the two sides are controlled first, and the bolt holes in the middle section of the web beam on the composite T-beam are not subject to hoisting errors. The bolt holes in the middle section of the web beam on the composite T-beam are evenly arranged, with a spacing of no more than 450mm and no less than 5 bolts; Step S5: Steel bar processing in beam-column joints, prestressed bar channel layout and prestressed bar punching After the composite T-beam is hoisted in place, the beam-column joint and the upper post-cast section of the composite T-beam can be processed; first, all the ordinary steel bars of the composite T-beam are effectively anchored into the beam-column joint, and the anchor length is not less than 35d, d is the diameter of the ordinary steel bars of the composite T-beam, and is not less than 800mm. When the anchor length of the ordinary steel bars cannot meet the design requirements, anchor plates can be set at the ends of the ordinary steel bars; the steel bars in the beam-column joint and the upper post-cast section of the composite T-beam should be arranged throughout the length, and the diameter of the main force bar should be not less than 30mm, and the requirements for the clear distance of the steel bars in the later concrete pouring should be met; for the arrangement requirements of the prestressed tendons, after the steel bars at the beam-column joint are installed, the prestressed tendons inside are perforated and the internal parts of the beam-column joints are Pre-embedded prestressed tendon ducts; the prestressed tendons inside the prefabricated composite T-beam are pierced from one end of the composite T-beam to the beam-column node by the traction method, and then the prestressed tendon duct inside the beam-column node is pierced through the composite T-beam at the other end, and the prestressed tendons are arranged crosswise to meet the linear trend of the prestressed tendons; the prestressed tendon ducts at the beam-column node are reliably pre-embedded with metal corrugated pipes, and the pre-embedded metal corrugated pipes inside the beam-column node should comply with the linear trend of the designed prestressed tendons. The metal corrugated pipes are fixed to the steel bars inside the beam-column node by additional stirrups, and the ends of the metal corrugated pipes are accurately connected with the reserved duct ports inside the composite T-beams on each side in the beam-column node, and reliably fixed, and the concealed project acceptance work is done well; Step S6: Bolt holes and negative moment rib installation After the prestressed tendons are laid, the high-strength bolts of the wing beam of the composite T-beam can be punched. The high-strength bolts on the wing beams on both sides are arranged in a "staggered wave" style, and are set asymmetrically to enhance the shear resistance of the composite T-beam. Then, the anti-negative bending moment ribs in the upper post-casting section of the composite T-beam are installed, and the installation holes on the anti-negative bending moment ribs are penetrated one by one with high-strength bolts for reliable fixation; at the beam-column node and within 1000mm on both sides, the anti-negative bending moment ribs should be set throughout the length, and incomplete installation phenomena such as splicing and welding of the anti-negative bending moment ribs shall not occur within this range, so as not to affect the overall structural stress performance. There shall be no less than 3 anti-negative bending moment ribs in the same direction, and their installation shall not affect the extension of the steel bars at the top of the precast column and the later concrete pouring process, and the process acceptance and record work shall be done well; Step S7: Hoisting of composite slabs and installation of aluminum formwork at beam-column joints The design adopts the integrated integral superposition cast-in-place forming of beams, plates and columns. On the basis of completing the above-mentioned process, the superimposed plates are hoisted in sections, modules and sections. The ends of the superimposed plates are fixed with high-strength bolts in the upper superimposed layer of the superimposed T-beam or the post-casting section by locally pre-embedded connecting steel plates. The steel bars at the ends of the superimposed plates in other parts extend into the superimposed layer of the superimposed T-beam. Additional steel bars are provided at the junction of the superimposed T-beam and the superimposed plates. The cutting length of the additional steel bars is not less than 1200mm, the diameter is not less than 10mm, and the spacing is not more than 100mm. The additional steel bars are placed on the negative moment ribs in the superimposed layer, and the additional steel bars should be spot welded and fixed to the negative moment ribs one by one. In order to meet the subsequent concrete pouring process, aluminum molds are used for rapid assembly at the beam-column nodes. When the aluminum molds are installed, elastic sealing strips are attached to the contact surfaces with the prefabricated columns and superimposed beams. The aluminum molds are tightened and fixed with the pre-embedded internal threads on the superimposed T-beams and prefabricated columns by screws to achieve the purpose of rapid installation. Step S8: Composite slab reinforcement binding and concealed engineering acceptance According to the construction plan, double-layer bidirectional steel mesh is used for the on-site hoisting construction of the composite slab. After the composite slab is hoisted into place, after the steel bar connection at the node between the composite slab and the composite T-beam is handled, the upper steel mesh is tied to the upper truss bar of the composite slab. The diameter of the distributed steel bars of the upper steel mesh is not less than 10mm, and the spacing of the distributed steel bars does not exceed 150mm. The distributed steel bars at the composite slab and the composite T-beam should be laid throughout the length and appropriately dense, with a spacing of no more than 100mm. During the on-site construction process, when the bonded prestressing technology is adopted, when the composite slab steel mesh is tied, the grouting holes and overflow holes should be reserved on the metal corrugated pipe installed in the post-casting section at the beam-column node, and the overall steel bar concealment project acceptance work should be done well. Step S9: integral pouring of concrete for beams, slabs and columns, tensioning of prestressed tendons, anchoring and grouting of holes. After all the above processes are completed and accepted, the concrete for beams, slabs and columns can be integrally poured. No construction joints shall be left at the beam-column joints. The concrete strength shall not be less than C30. The concrete pouring at the joints between precast columns and superimposed T-beams, and between superimposed T-beams and superimposed slabs shall be strengthened with vibration to ensure the quality of the concrete pouring at the joints. The curing time shall not be less than 7 days. For the tensioning and anchoring of prestressed tendons on site, the tensioning and anchoring of prestressed tendons can be carried out only when all structures of the layer are completed and the concrete strength reaches 100% of the design strength. 1.03σcom over-tensioning, symmetrical tensioning, and timely grouting are adopted. The prestressed tendons are anchored at the ends or bottom of the superimposed T. The tensioning and anchoring of the prestressed tendons are completed symmetrically from the middle of the structure to both ends. The tensioning and anchoring are carried out simultaneously to ensure the dense grouting. A dedicated person is assigned to supervise the process and good acceptance records are kept. Step S10: Flow construction, repeating steps 1 to 9 until all structural construction is completed On-site hoisting construction, the hoisting connection of prefabricated columns and composite T-beams has become the focus of the technical solution. The seismic design and construction of beam-column nodes are a significant manifestation of the technical solution's structural innovation and process optimization. For engineering projects with beam-column spans exceeding 12m, special scheme certification should be carried out to ensure the operational safety of the hoisting project. According to the technical solution, a flow construction organization form is adopted, and the above process steps 1 to 9 are repeated until the hoisting construction of the entire structure is completed, and finally the project acceptance and material archiving are carried out.

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