CN111203977B

CN111203977B - Construction method of prefabricated box girder

Info

Publication number: CN111203977B
Application number: CN202010065759.3A
Authority: CN
Inventors: 许世辉; 罗俊; 黄鹏; 何旭阳; 李思艳
Original assignee: Sichuan Luhang Building Engineering Co ltd
Current assignee: Sichuan Luhang Building Engineering Co ltd
Priority date: 2020-01-20
Filing date: 2020-01-20
Publication date: 2021-03-26
Anticipated expiration: 2040-01-20
Also published as: CN111203977A

Abstract

The invention relates to a construction method of a prefabricated box girder, which comprises the following steps: 1) construction preparation; 2) binding a reinforcement cage; 3) hoisting the box girder reinforcement cage; 4) erecting a box girder template; 5) pouring concrete; 6) steam curing of the prefabricated box girder; 7) and (5) performing water spraying maintenance on the prefabricated box girder. The invention has the beneficial effects that: according to the invention, the position of the box girder stirrup can be limited through the stirrup embedded groove on the stirrup limiting plate, and the positions of the box girder longitudinal rib at the lower layer and the box girder longitudinal rib at the upper layer are limited through the longitudinal rib limiting groove and the longitudinal rib limiting ring respectively, so that the difficulty in binding and positioning the steel bars of the box girder steel reinforcement cage is reduced; meanwhile, the suspension platform plate is arranged on the upper part of the upper-layer bed plate, and the transverse position of the bed plate slide beam can be adjusted through the slide beam roller, so that the box beam reinforcement cage is prevented from being trampled in the construction process of the box beam reinforcement cage.

Description

Construction method of prefabricated box girder

Technical Field

The invention relates to a construction method of a prefabricated box girder, belongs to the field of bridge engineering, and is suitable for prefabricated box girder preparation engineering.

Background

In the bridge engineering construction process, more and more viaducts adopt prefabricated box girders to improve the construction efficiency and protect the construction environment. In the construction process of the prefabricated box girder, the binding quality of a reinforcement cage, the formwork erecting effect and the maintenance construction quality and efficiency are always the key points of control.

In the prior art, a construction method for a precast concrete box girder includes the following steps: 1) prefabricating a concrete pedestal on the ground; 2) presetting hoisting steel strands on a pedestal, mounting a steel base plate, arranging channel steel on the pedestal, and arranging a sealing rubber bar in the channel steel; 3) hoisting a side template of the outer mold, and locking and fixing the lower part of the upright post through a lower mold closing screw rod; 4) coating a release agent on the inner sides of the pedestal, the steel base plate and the side template; 5) laying box girder steel bars in the outer mould; 6) hoisting the inner mold to the inner side of the steel bar of the box girder, and fixing the inner mold through a locking bolt; 7) connecting the upper ends of the stand columns through upper mold closing screws, and then hoisting the end mold plate; 8) pouring concrete; 9) and (6) demolding. Although this technique can satisfy precast concrete box girder preparation, but fail to solve the quick maintenance problem of precast box girder, be difficult to effectively promote the quality that steel reinforcement cage ligature location and template were established.

In view of the above, in order to improve the preparation construction quality of the precast concrete box girder, the construction method of the precast concrete box girder, which can improve the positioning and binding construction quality of the reinforcement cage and improve the concrete pouring and curing effects, is urgently needed to be invented at present.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide the construction method of the prefabricated box girder, which can improve the preparation construction efficiency of the reinforcement cage, improve the erecting quality of the template and improve the maintenance effect of the box girder components.

The construction method of the precast box girder comprises the following steps:

1) construction preparation: reinforcing the beam field foundation, and arranging a box beam buttress on the beam field foundation; determining the mixing proportion of concrete; preparing a device required by construction;

2) binding a reinforcement cage: two rows of bed-jig bottom support rods and two rows of bed-jig support columns are arranged on the bed-jig bottom plate; firstly, a stirrup limiting plate and a plate bottom limiting tenon are arranged on the outer side wall of the lower bed plate, then the lower bed plate is hoisted to a bed jig bottom plate, a bottom plate bearing plate is connected with the plate bottom limiting tenon on the lower surface of the lower bed plate, and the inclination angle of the lower bed plate is adjusted through a bed plate bottom support rod; firstly, placing the box girder stirrups of the lower layer in the stirrup embedded grooves, and then placing the box girder longitudinal reinforcements of the lower layer in the longitudinal reinforcement limiting grooves to finish the binding construction of the box girder longitudinal reinforcements of the lower layer and the box girder stirrups; embedding a sliding beam connecting plate at the lower part of a bed plate sliding beam into a sliding beam chute of a column top support beam, connecting a bed plate sling and a bed plate suspender with a bed plate connecting ring and a bed plate connecting bolt respectively, controlling the spatial position of an upper bed plate through the bed plate sling and the bed plate suspender, sliding the upper bed plate to the upper part of a lower bed plate, and enabling a box beam longitudinal rib at the upper layer to pass through a longitudinal rib limiting ring; placing a supporting beam positioning bolt on the upper surface of the upper-layer bed plate, and sequentially arranging a platform supporting beam and a suspension platform plate at the top end of the supporting beam positioning bolt; binding construction of a box girder reinforcement cage is carried out on the suspension platform plate; the stirrup limiting plate is provided with a stirrup embedded groove;

3) hoisting construction of the box girder steel reinforcement cage: removing the upper bed plate, and removing the restraint of the bed plate sling and the bed plate sling rod on the upper bed plate; firstly, arranging a hoisting connecting plate at the lower part of the box girder steel reinforcement cage, then enabling a hoisting screw to penetrate through a gap of the box girder steel reinforcement cage, and then enabling the hoisting screw and the hoisting connecting plate to be firmly connected through a screw fastening bolt;

4) erecting a box girder template: after the inclination angle of the template angle adjusting plate is adjusted through the template angle adjusting bolt on the template bottom supporting plate, the adjusting support body is arranged in a gap between the template bottom supporting plate and the template angle adjusting plate, and stable support is provided for the template angle adjusting plate; firstly, arranging a template supporting body on the top surface of a template angle adjusting plate, synchronously hoisting a box girder bottom die and box girder side dies onto the template supporting body, and arranging side die adjusting tenons at joints of the box girder side dies; an adjusting falcon pressing plate is arranged on the outer side wall of the side-form adjusting falcon, and the adjusting falcon pressing plate is firmly connected with the side form of the box girder through bolts; inserting the side die connecting plate into the connecting plate limiting groove, controlling the inclination angle of the side die of the box girder through the side die pressing rod, and firmly connecting the connecting plate limiting groove and the side die connecting plate by adopting a connecting plate positioning bolt; integrally hoisting a box girder reinforcement cage formed by binding box girder stirrups, box girder longitudinal reinforcements and panel reinforcements to the upper parts of a box girder bottom mould and box girder side moulds; the box girder inner mold is penetrated into the box girder steel reinforcement cage along the direction parallel to the box girder longitudinal reinforcement, and the inner mold supporting plate is embedded into the inner mold supporting groove; respectively applying jacking force to the box girder inner mold through the first inner mold support rod and the second inner mold support rod to correct the spatial position of the box girder inner mold; controlling the position of a steel reinforcement cage of the box girder by a steel reinforcement position control device; connecting the top die of the box girder with the top of the side die of the box girder, and enabling the panel steel bars to penetrate through the gluten penetrating grooves; arranging a top die top connecting plate on the panel steel bar; synchronously limiting the transverse position of the box girder top mold through a top mold side supporting rod and a top mold connecting bolt on the top mold top connecting plate; placing a box girder end mold on the outer sides of a box girder bottom mold and a box girder inner mold, and firmly connecting the box girder bottom mold, the box girder side mold, the box girder top mold and the box girder inner mold with the box girder end mold through template connecting bolts;

5) and (3) concrete pouring construction: pouring concrete into a cavity formed by enclosing a box girder bottom mould, a box girder side mould, a box girder top mould and a box girder inner mould by adopting concrete pouring equipment to form a prefabricated box girder;

6) steam curing of the prefabricated box girder: arranging a strut beam at the top end of the transversely opposite maintenance strut, respectively arranging strut bottom plates at the bottom ends of the maintenance struts, and arranging bottom plate rollers between the strut bottom plates and the beam field foundation; arc-shaped supporting beams with arc-shaped planes are arranged at the upper parts of the pillar cross beams, and rain-proof curtain cloth is arranged between the adjacent arc-shaped supporting beams; arranging steam-cured inclined struts on two sides of the steam-cured cross beam respectively, and arranging inclined strut rotating hinges at the joints of the steam-cured cross beam and the steam-cured inclined struts; a beam position adjusting bolt on the upper surface of the steam-curing beam is connected with the strut beam, and an elastic position control body is arranged between the strut beam and the steam-curing beam; the maintenance support column, the steam-curing cross beam and the steam-curing inclined strut which are connected with the maintenance support column and the support column cross beam into a whole are moved to a set position along the length direction of the precast box girder through external traction equipment; adjusting the inclination angle of the steam-cured inclined strut through a second position-adjusting transverse bolt, adjusting the elevation of the steam-cured cross beam through a cross beam position-adjusting bolt, and firmly connecting the closed bottom plate with the beam field foundation through a bottom plate compaction bolt; inserting the steam-curing spraying pipe into a cavity formed by the steam-curing curtain cloth and the prefabricated box girder along the direction parallel to the prefabricated box girder, communicating external steam supply equipment with the steam-curing spraying pipe, and performing steam curing on the prefabricated box girder;

7) and (3) water spraying maintenance of the prefabricated box girder: firstly, placing a prefabricated box girder on a box girder buttress, and then placing a water spraying box in a cavity inside the prefabricated box girder; the position of the water spraying box in the cavity is controlled in the prefabricated box girder through the position control rod, and the outer side wall of the box girder bottom plate is connected with the first water collecting groove plate; the sliding support column connected with the transverse water spraying pipe and the inclined water spraying pipe is moved to a set position through an external traction device, and the inclination angle of the inclined water spraying pipe is adjusted through a first position-adjusting transverse bolt; arranging a second water collecting groove plate at the lower part of the precast box girder; collecting redundant curing water through a residual water collecting box below the first water collecting groove plate and the second water collecting groove plate; and synchronously spraying water to the prefabricated box girder through the intracavity nozzle and the extraluminal nozzle to perform water spraying maintenance of the prefabricated box girder.

Preferably, the method comprises the following steps: step 2) rolling the jig frame support columns by using section steel columns or steel pipes, and placing column top support beams at the top ends of the jig frame support columns in the same row; the column top supporting beam is formed by rolling a steel plate, and a sliding beam sliding groove connected with a sliding beam connecting plate is arranged on the column top supporting beam; the lower part of the sliding beam connecting plate is provided with a sliding beam roller; the bed plate bottom stay bar is formed by combining a screw and a bolt, and a stay bar top hinge and a bottom plate bearing plate are arranged at the top end of the screw; the lower bed mould plate and the upper bed mould plate are both formed by rolling steel plates or aluminum alloy templates, and a bed mould plate position adjusting hinge is arranged at the joint of the connected lower bed mould plate or the connected upper bed mould plate; the side wall of the lower layer tire plate facing the upper layer tire plate side is provided with a longitudinal rib limiting groove; the side wall of the upper layer tire plate facing the lower layer tire plate is provided with a longitudinal rib limiting ring, and the other side wall is provided with a tire plate connecting ring and a tire plate connecting bolt.

Preferably, the method comprises the following steps: and 3) the plane of the hoisting connecting plate is rectangular and is arranged parallel to the longitudinal ribs of the box girder, the hoisting connecting plate is formed by rolling a steel plate, and a vertical hole for a hoisting screw to pass through and a stirrup embedded groove connected with the stirrup of the box girder are formed in the hoisting connecting plate.

Preferably, the method comprises the following steps: step 4), the template support body is formed by rolling profile steel and is arranged in parallel to the direction of the longitudinal ribs of the box girder; the thickness of the side-die adjusting falcon is the same as that of the side die of the box girder, and the cross section of the side-die adjusting falcon is in a T shape; the box girder bottom die, the box girder side die, the box girder inner die and the box girder top die are all made of steel plates or alloy templates, and reinforcing steel bar position control devices are arranged on the box girder bottom die and the box girder inner die; the lower surface of the bottom die of the box girder is provided with a connecting plate limiting groove, and the top die of the box girder is provided with a hole for a top die connecting bolt to pass through; the top of the box girder side mold is provided with a top mold connecting plate and a top mold connecting bolt, and the top mold connecting bolt is vertically welded and connected with the top mold connecting plate; the box girder inner die comprises an inner die top plate, an inner die bottom plate and an inner die side plate, inner die supporting grooves with mirror images opposite to each other are formed in the lower surface of the inner die top plate and the upper surface of the inner die bottom plate, inner die adjusting tenons are arranged on the inner die side plate, and a template rotating hinge is arranged at the connecting part of the inner die bottom plate and the inner die side plate; template connecting support plates are respectively arranged on the outer side walls of the inner mold bottom plate and the box girder bottom mold; the thickness of the inner die adjusting falcon is the same as that of the inner die top plate, and the cross section of the inner die adjusting falcon is in a T shape; the steel bar position control device comprises a position control support plate, a position control support plate and a position adjusting screw rod, and 2-4 sets of steel bar position control devices are respectively arranged on the bottom die of the box girder and the inner die of the box girder on the top layer; the position adjusting screw is formed by rolling a screw, the position adjusting screw is vertically welded or connected with the position control support plate through threads, and the position adjusting screw is connected with the position control support plate through threads; the cross section of the position control supporting plate is U-shaped and is formed by rolling a steel plate, and the position control supporting plate is welded with the box girder bottom die or the box girder inner die; the position control support plate is formed by rolling a steel plate and is cylindrical, the height of the position control support plate is 10-20 mm thicker than the thickness of the steel bar protective layer, and a support plate airtight plate is stuck to the outer side wall of the position control support plate along the annular direction; the top die top connecting plate is formed by rolling a steel plate and is connected with a panel steel bar through a bolt, and a top die side supporting rod is arranged on the upper surface of the top die top connecting plate; the first inner mold supporting rod and the second inner mold supporting rod are formed by combining a screw and a bolt, and the fastening directions of the screws on the two sides of the bolt are opposite; two ends of the first inner mold support rod are respectively connected with the inner mold support plate and the inner mold position control column in a vertical welding mode or in a threaded mode; both ends of the second inner mold supporting rod are connected with the adjusting falcon pressing plate and the inner mold position control column through the supporting rod rotating hinge; the inner mould position control column is formed by rolling a steel plate or profile steel and is arranged inside the box girder inner mould along the length direction; the box girder end die is provided with a channel connected with the box girder bottom die, the box girder side die, the box girder top die and the box girder inner die, and a pipeline through hole is arranged at a position corresponding to a preset pipeline; the cross section of the pipeline through hole is circular, and a pipeline sealing ring is arranged on the inner side wall of the pipeline through hole; the pipeline closed ring is formed by sewing a geomembrane or a rubber sheet and is stuck and connected with the inner side wall of the pipeline penetrating hole, and the pipeline closed ring is provided with a closed control pipe.

Preferably, the method comprises the following steps: step 7) the intracavity water spraying box comprises a water spraying box inner box and a water spraying box outer box, and the lower surface of the intracavity water spraying box is provided with a shifting roller; the inner water spraying box is formed by rolling a steel plate, the outer water spraying box is made of a rubber plate or a PVC plate material, and an intracavity spray head is arranged on the outer side wall of the outer water spraying box; the first water collecting channel plate and the second water collecting channel plate are rolled into an upper concave groove-shaped structure by adopting steel plates, water leakage groove holes are formed in the first water collecting channel plate and the second water collecting channel plate, and the lower surfaces of the first water collecting channel plate and the second water collecting channel plate are connected with a residual water collecting box; one side of the second water collecting groove plate is connected with the sliding support column, and the other side of the second water collecting groove plate is provided with a fixed support plate; the fixed support plate is arranged in parallel to the second water collecting groove plate, and an elastic control body and a closed pressing plate are sequentially arranged on the fixed support plate; an outer box clapboard and an intracavity water supply pipe are arranged between the inner box of the water spraying box and the outer box of the water spraying box; the sliding support column is formed by rolling steel pipes or section steel, the top end of the sliding support column is vertically welded with the transverse water spraying pipe, the bottom end of the sliding support column is vertically welded with the sliding bottom plate, and a bottom plate roller is arranged between the sliding bottom plate and the beam field foundation; the first positioning transverse bolt comprises a screw rod and a bolt, the fastening directions of the screw rods on the two sides of the bolt are opposite, one end of the first positioning transverse bolt is vertically welded and connected with the sliding support column, and the other end of the first positioning transverse bolt is connected with the inclined water spraying pipe through a positioning bolt rotating hinge; the transverse spray pipe and the inclined spray pipe are both formed by rolling steel pipes, a spray pipe rotating hinge is arranged at the joint of the inclined spray pipe and the transverse spray pipe, and the inclined spray pipe and the transverse spray pipe are communicated with a water supply pipe outside the cavity; the transverse water spraying pipe and the oblique water spraying pipe are respectively communicated with an external water supply pipe, and an outer cavity spray head is arranged on the side wall of the transverse water spraying pipe and the side wall of the oblique water spraying pipe facing the precast box girder.

Preferably, the method comprises the following steps: step 6), the pillar beam is formed by rolling steel pipes or section steel and is connected with the rainproof cord fabric in a sticking way or through screws; the rainproof cord fabric is formed by cutting a geomembrane or a rubber sheet; the steam-curing beam is formed by rolling a steel pipe or profile steel, and the upper surface of the steam-curing beam is vertically welded and connected with the beam position adjusting bolt; the cross beam position adjusting bolt is formed by rolling a screw; the elastic control body is formed by rolling a spring material, and the bottom end of the elastic control body is welded with the steam-curing beam; the steam-curing inclined strut is formed by rolling a steel pipe or profile steel, a second position-adjusting transverse bolt is arranged on the side, away from the precast box girder, of the side wall of the steam-curing inclined strut, the second position-adjusting transverse bolt is connected with the steam-curing inclined strut through a position-adjusting bolt rotating hinge, a position-controlling transverse plate is arranged at the bottom end of the steam-curing inclined strut, and a bottom plate compacting bolt is arranged on the position-controlling transverse plate; the bottom plate compaction bolt is connected with the position control transverse plate through a screw; the steam-cured cross beams and the steam-cured diagonal braces are arranged for 2-4 times along the length direction of the precast box girder, and closed steam-cured curtain cloth is arranged between the adjacent steam-cured cross beams and between the adjacent steam-cured diagonal braces; the steam-cured curtain cloth adopts a geomembrane, and a closed bottom plate is arranged at the joint of the bottom end of the steam-cured curtain cloth and the beam yard foundation; the closed bottom plate is a rubber plate and is arranged in a whole length direction along the length direction of the steam-cured curtain cloth; the maintenance steam injection pipe is a steel pipe or a PVC pipe, one end of the maintenance steam injection pipe is closed, the other end of the maintenance steam injection pipe is communicated with external steam supply equipment, and a steam injection hole is formed in the pipe wall of the maintenance steam injection pipe.

The invention has the beneficial effects that:

(1) according to the invention, the position of the box girder stirrup can be limited through the stirrup embedded groove on the stirrup limiting plate, and the positions of the box girder longitudinal rib at the lower layer and the box girder longitudinal rib at the upper layer are limited through the longitudinal rib limiting groove and the longitudinal rib limiting ring respectively, so that the difficulty in binding and positioning the steel bars of the box girder steel reinforcement cage is reduced; meanwhile, the suspension platform plate is arranged on the upper part of the upper-layer bed plate, and the transverse position of the bed plate slide beam can be adjusted through the slide beam roller, so that the box beam reinforcement cage is prevented from being trampled in the construction process of the box beam reinforcement cage.

(2) According to the invention, the hoisting connecting plates are respectively arranged at the lower part of the box girder steel reinforcement cage and the lower part of the panel steel reinforcement, the hoisting screw is connected with the hoisting connecting plates, the hoisting connecting plates are tightly connected with the box girder steel reinforcement cage through the screw fastening bolts, and the damage of hoisting construction to the box girder steel reinforcement cage is reduced; meanwhile, after the hoisting screw is connected with the bed plate sliding beam, the hoisting screw can transversely move along the column bottom supporting beam, so that the difficulty in shifting the box girder reinforcement cage is reduced.

(3) The spatial positions of the box girder side die and the box girder top die can be limited through the side die pressing rod and the top surface side supporting rod respectively, the inclination angle of the box girder bottom die can be adjusted through the template angle adjusting bolt, and the difficulty in positioning the spatial positions of the box girder side die, the box girder top die and the box girder bottom die is reduced; meanwhile, the template adjusting tenons are respectively arranged on the box girder side mold and the box girder inner mold, so that the difficulty of size adjustment and on-site template removal of the templates can be reduced; the steel bar position control devices are respectively arranged on the box girder bottom die and the box girder inner die, so that the dynamic control on the space position of the box girder steel bar cage can be realized; the side wall of the box girder inner mold is provided with the inner mold supporting groove, the position of the box girder inner mold can be limited through the inner mold position control column, the first inner mold supporting rod and the second inner mold supporting rod, and the difficulty of dismantling construction of the box girder inner mold can be reduced while the position control accuracy of the box girder inner mold is improved.

(4) According to the invention, the transverse water spraying pipe and the inclined water spraying pipe are arranged on the outer side of the prefabricated box girder, so that water spraying maintenance can be synchronously carried out on the outer side wall of the prefabricated box girder; meanwhile, the inner side of the prefabricated box girder is provided with the intracavity water spraying box which can move along the inner side of the prefabricated box girder, and the water spraying maintenance can be carried out on the inner side wall of the prefabricated box girder through an intracavity water supply pipe and an intracavity spray head; according to the invention, the first water collecting channel plates are respectively arranged at the two ends of the precast box girder, and the second water collecting channel plate is arranged below the inclined water spraying pipe, so that residual water for maintenance can be synchronously recovered, and the influence of water spraying maintenance construction on the external environment is reduced.

(5) According to the steam-curing cross beam and the steam-curing inclined strut, the elevation and the inclination angle of the steam-curing cross beam and the steam-curing inclined strut can be controlled through the cross beam position-adjusting bolt and the second position-adjusting cross bolt respectively, so that the effective control of a steam-curing space is realized; meanwhile, the position control transverse plate is arranged at the bottom end of the steam-curing inclined support, and downward pressure can be applied to the closed bottom plate through the bottom plate compaction bolt, so that the airtightness of a steam-curing space is improved; meanwhile, the maintenance support column and the support column cross beam can move through the bottom plate roller, so that the difficulty of site displacement is reduced; the upper part of the pillar beam is provided with the arc-shaped supporting beam and the rainproof curtain cloth, so that the influence of the external environment on the maintenance construction of the prefabricated box beam can be reduced.

Drawings

FIG. 1 is a flow chart of the construction of the precast box girder of the present invention;

FIG. 2 is a schematic diagram of a construction structure for binding a steel reinforcement cage of a box girder;

FIG. 3 is a schematic view of the stirrup limiting plate configuration of FIG. 2;

FIG. 4 is a schematic diagram of a hoisting construction structure of a steel reinforcement cage of a box girder;

FIG. 5 is a schematic view of the hanger plate of FIG. 4;

FIG. 6 is a schematic view of a supporting structure of the box girder template;

FIG. 7 is a schematic view of the positioning device of FIG. 6;

FIG. 8 is a schematic view of the box girder top mold structure of FIG. 6;

FIG. 9 is a schematic view of the box girder end form installation construction of FIG. 6;

FIG. 10 is a schematic view of a water-spraying maintenance construction of the precast box girder;

FIG. 11 is a schematic view of the arrangement of the intracavity spray tank and the first catchment trough plate of FIG. 10;

FIG. 12 is a schematic view of a steam curing construction structure of a precast box girder;

FIG. 13 is a schematic view of the arrangement structure of the arc-shaped supporting beam and the rain-proof curtain cloth in FIG. 12;

fig. 14 is a sectional view of the structure of the curing nozzle of fig. 12.

Description of reference numerals: 1-beam field foundation; 2-prefabricating a box girder; 3-bed jig bottom plate; 4-bed plate bottom brace rod; 5-a jig frame support column; 6-lower bed mould plate; 7-stirrup limiting plate; 8-limiting falcon at the bottom of the plate; 9-a bottom plate bearing plate; 10-box girder buttress; 11-box girder stirrups; 12-stirrup-embedded grooves; 13-box girder longitudinal ribs; 14-longitudinal rib limiting grooves; 15-bed plate sliding beam; 16-a skid beam connection plate; 17-column top bracing beam; 18-sliding beam runner; 19-bed plate slings; 20-bed plate hanger bar; 21-a bed plate connecting ring; 22-a bed plate connecting bolt; 23-upper layer tire plate; 24-longitudinal rib limiting rings; 25-beam positioning bolt; 26-a platform support beam; 27-a suspended platform plate; 28-box girder reinforcement cage; 29-hoisting the connecting plate; 30-hoisting a screw rod; 31-screw fastening bolt; 32-template bottom supporting plate; 33-template angle-adjusting bolt; 34-template angle adjusting plates; 35-adjusting the support; 36-a template support; 37-box girder bottom die; 38-box beam side molds; 39-template connecting support plates; 40-side die adjusting falcon; 41-adjusting falcon pressing plates; 42-side die-connecting plate; 43-connecting plate limiting groove; 44-sideform compression bar; 45-connecting plate positioning bolts; 46-panel rebar; 47-box girder inner mould; 48-inner supporting plate; 49-inner mold supporting groove; 50-a first inner mold strut; 51-a second inner mold strut; 52-a steel bar position control device; 53-box girder top mould; 54-gluten is arranged in a groove; 55-top mould top connecting plate; 56-top mould side stay bar; 57-top mold connecting bolt; 58-vapor injection holes; 59-box beam end mould; 60-template connecting bolts; 61-water spraying box in cavity; 62-a position control rod; 63-box girder bottom plate; 64-a first sink plate; 65-transverse water spraying pipe; 66-oblique water spraying pipe; 67-sliding support columns; 68-first positioning cross bolt; 69-a second catchment channel plate; 70-residual water collecting box; 71-intracavity spray heads; 72-extra-cavity showerhead; 73-maintaining the pillars; 74-post beam; 75-a strut bottom plate; 76-floor rollers; 77-arc supporting beam; 78-rain-proof curtain cloth; 79-steam curing beam; 80-steam-curing inclined struts; 81-inclined strut rotating hinge; 82-beam positioning bolt; 83-elastic control body; 84-second positioning cross bolt; 85-a bottom plate compaction bolt; 86-a closed bottom plate; 87-maintaining the steam injection pipe; 88-steam-curing the cord fabric; 89-sliding beam roller; 90-stay bar top hinge; 91-position control transverse plates; 92-positioning hinge of the bed plate; 93-a top die connecting plate; 94-inner mold top plate; 95-inner mold bottom plate; 96-inner mold side plates; 97-inner die adjusting falcon; 98-position control support plate; 99-a position control supporting plate; 100-positioning screw rod; 101-a support plate airtight plate; 102-inner mode control position post; 103-a pipeline is perforated; 104-a pipe containment ring; 105-a closed control tube; 106-inner box of water spraying box; 107-spray box outer box; 108-a shifting roller; 109-water leakage slot holes; 110-a fixed support plate; 111-positioning bolt rotary hinge; 112-sealing the pressing plate; 113-outer box baffle; 114-intracavity water supply pipe; 115-a skid baseplate; 116-the spray pipe is hinged; 117-brace bar rotation hinge; 118-template pivot hinge; 119-external cavity water supply pipe.

Detailed Description

The present invention will be further described with reference to the following examples. The following examples are set forth merely to aid in the understanding of the invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

Referring to fig. 1, the construction method of the precast box girder includes the following construction steps:

1) construction preparation: reinforcing the beam field foundation 1, and arranging a box girder buttress 10 on the beam field foundation 1; determining the mixing proportion of concrete; preparing a device required by construction;

2) binding a reinforcement cage: two rows of bed-jig bottom stay bars 4 and two rows of bed-jig support columns 5 are arranged on the bed-jig bottom plate 3; firstly, a stirrup limiting plate 7 and a plate bottom limiting tenon 8 are arranged on the outer side wall of a lower-layer bed plate 6, then the lower-layer bed plate 6 is hoisted to a bed jig bottom plate 3, a bottom plate bearing plate 9 is connected with the plate bottom limiting tenon 8 on the lower surface of the lower-layer bed plate 6, and the inclination angle of the lower-layer bed plate 6 is adjusted through a bed plate bottom support rod 4; firstly, placing the box girder stirrups 11 on the lower layer in the stirrup embedded grooves 12, and then placing the box girder longitudinal reinforcements 13 on the lower layer in the longitudinal reinforcement limiting grooves 14 to finish the binding construction of the box girder longitudinal reinforcements 13 on the lower layer and the box girder stirrups 11; firstly, embedding a sliding beam connecting plate 16 at the lower part of a bed plate sliding beam 15 into a sliding beam chute 18 of a column top supporting beam 17, then respectively connecting a bed plate sling 19 and a bed plate suspender 20 with a bed plate connecting ring 21 and a bed plate connecting bolt 22, controlling the spatial position of an upper bed plate 23 through the bed plate sling 19 and the bed plate suspender 20, then sliding the upper bed plate 23 to the upper part of a lower bed plate 6, and enabling a box beam longitudinal rib 13 at the upper layer to pass through a longitudinal rib limiting ring 24; a supporting beam positioning bolt 25 is arranged on the upper surface of the upper-layer bed plate 23, and a platform supporting beam 26 and a suspension platform plate 27 are sequentially arranged at the top end of the supporting beam positioning bolt 25; binding construction of a box girder reinforcement cage 28 is performed on the suspension platform plate 27;

3) hoisting construction of the box girder steel reinforcement cage 28: removing the upper bed plate 23 and releasing the bed plate sling 19 and the bed plate hanger rod 20 from restraining the upper bed plate 23; firstly, arranging a hoisting connecting plate 29 at the lower part of the box girder steel reinforcement cage 28, then enabling a hoisting screw 30 to penetrate through a gap of the box girder steel reinforcement cage 28, and then enabling the hoisting screw 30 and the hoisting connecting plate 29 to be firmly connected through a screw fastening bolt 31;

4) erecting a box girder template: after the inclination angle of the template angle adjusting plate 34 is adjusted through the template angle adjusting bolt 33 on the template bottom supporting plate 32, the adjusting support body 35 is arranged in the gap between the template bottom supporting plate 32 and the template angle adjusting plate 34, and the template angle adjusting plate 34 is stably supported; firstly, arranging a template supporting body 36 on the top surface of the template angle adjusting plate 34, then synchronously hoisting a box girder bottom die 37 and box girder side dies 38 onto the template supporting body 36, and arranging side die adjusting tenons 40 at joints of the box girder side dies 38; an adjusting falcon pressing plate 41 is arranged on the outer side wall of the side-mould adjusting falcon 40, and the adjusting falcon pressing plate 41 is firmly connected with the box girder side mould 38 through bolts; inserting the side die connecting plate 42 into the connecting plate limiting groove 43, controlling the inclination angle of the side die 38 of the box girder through the side die pressing rod 44, and firmly connecting the connecting plate limiting groove 43 and the side die connecting plate 42 by using the connecting plate positioning bolt 45; integrally hoisting a box girder reinforcement cage 28 formed by binding box girder stirrups 11, box girder longitudinal reinforcements 13 and panel reinforcements 46 to the upper parts of a box girder bottom die 37 and box girder side dies 38; firstly, the box girder inner mold 47 is penetrated into the box girder steel reinforcement cage 28 along the direction parallel to the box girder longitudinal ribs 13, the inner mold supporting plate 48 is embedded into the inner mold supporting groove 49, and the first inner mold supporting rod 50 and the second inner mold supporting rod 51 apply top pressure to the box girder inner mold 47 respectively to correct the space position of the box girder inner mold 47; the position of the box girder reinforcement cage 28 is controlled by the reinforcement position control device 52; connecting the top box girder mold 53 with the top of the side box girder mold 38 and passing the panel reinforcement 46 through the gluten passing groove 54; a top die top connecting plate 55 is arranged on the panel steel bar 46; the lateral position of the box girder top mold 53 is defined by the top mold side stay bars 56 and the top mold connecting bolts 57 on the top mold top link plate 55 in synchronization; placing the box girder end mold 59 on the outer sides of the box girder bottom mold 37 and the box girder inner mold 47, and firmly connecting the box girder bottom mold 37, the box girder side mold 38, the box girder top mold 53 and the box girder inner mold 47 with the box girder end mold 59 through the template connecting bolt 60;

5) and (3) concrete pouring construction: pouring concrete into a cavity formed by enclosing the box girder bottom mould 37, the box girder side mould 38, the box girder top mould 53 and the box girder inner mould 47 by adopting concrete pouring equipment to form the prefabricated box girder 2;

6) steam curing of the prefabricated box girder: arranging strut beams 74 at the top ends of the transversely opposite maintenance struts 73, arranging strut bottom plates 75 at the bottom ends of the maintenance struts 73 respectively, and arranging bottom plate rollers 76 between the strut bottom plates 75 and the beam yard foundation 1; arc-shaped supporting beams 77 with arc-shaped planes are arranged at the upper parts of the pillar cross beams 74, and rain-proof curtain cloth 78 is arranged between the adjacent arc-shaped supporting beams 77; two sides of the steam-curing cross beam 79 are respectively provided with a steam-curing inclined strut 80, and an inclined strut rotating hinge 81 is arranged at the joint of the steam-curing cross beam 79 and the steam-curing inclined strut 80; a beam position adjusting bolt 82 on the upper surface of the steam-curing beam 79 is connected with the pillar beam 74, and an elastic position control body 83 is arranged between the pillar beam 74 and the steam-curing beam 79; the maintenance support column 73, and the steam-curing cross beam 79 and the steam-curing diagonal brace 80 which are connected with the maintenance support column 73 and the support cross beam 74 into a whole are moved to a set position along the length direction of the precast box girder 2 by external traction equipment; firstly, adjusting the inclination angle of the steam-cured inclined strut 80 through a second position-adjusting transverse bolt 84, then adjusting the elevation of the steam-cured cross beam 79 through a cross beam position-adjusting bolt 82, and then firmly connecting a closed bottom plate 86 with the beam yard foundation 1 through a bottom plate compaction bolt 85; inserting a steam curing spray pipe 87 into a cavity formed by the steam curing curtain cloth 88 and the prefabricated box girder 2 along the direction parallel to the prefabricated box girder 2, communicating external steam supply equipment with the steam curing spray pipe 87, and performing steam curing on the prefabricated box girder 2;

7) and (3) water spraying maintenance of the prefabricated box girder: placing the precast box girder 2 on the box girder buttress 10, and placing the intracavity water spraying box 61 inside the precast box girder 2; the position of the water spraying box 61 in the cavity is controlled in the prefabricated box girder 2 through a position control rod 62, and the outer side wall of a box girder bottom plate 63 is connected with a first water collecting groove plate 64; the sliding support column 67 connected with the transverse water spray pipe 65 and the inclined water spray pipe 66 is moved to a set position through an external traction device, and the inclination angle of the inclined water spray pipe 66 is adjusted through a first position-adjusting transverse bolt 68; a second water collecting groove plate 69 is arranged at the lower part of the prefabricated box girder 2; collecting the surplus maintenance water through the surplus water collection tank 70 under the first and second

catchment channel plates

64 and 69; and synchronously spraying water to the precast box girder 2 through the intracavity nozzle 71 and the extraluminal nozzle 72 to finish the water spraying maintenance of the precast box girder 2.

Referring to fig. 2 to 14, the prefabricated box girder limits the position of the longitudinal rib 13 of the box girder through the longitudinal rib limiting groove 14 and the longitudinal rib limiting ring 24; a hoisting connecting plate 29 is arranged at the lower part of the box girder reinforcement cage 28, and a hoisting screw 30 is connected with the bed plate sliding beam 15; side die adjusting tenons 40 are arranged on the side dies 38 of the box girder, and reinforcing steel bar position control devices 52 are respectively arranged on the bottom die 37 of the box girder and the inner die 47 of the box girder; the position of the box girder inner mould 47 can be limited by the inner mould position control column 102 and the first inner mould stay 50 and the second inner mould stay 51; arranging a transverse water spraying pipe 65 and an inclined water spraying pipe 66 at the outer side of the prefabricated box girder 2, and arranging an intracavity water spraying box 61 at the inner side; the two ends of the precast box girder 2 are respectively provided with a first water collecting groove plate 64, and a second water collecting groove plate 69 is arranged below the inclined water spraying pipe 66; the elevation and the inclination angle of the steam-curing cross beam 79 and the steam-curing inclined strut 80 are controlled by a cross beam position-adjusting bolt 82 and a second position-adjusting cross bolt 84 respectively, and an arc-shaped strut beam 77 and a rainproof curtain 78 are arranged at the upper part of the strut cross beam 74.

The beam field foundation 1 is cohesive soil in a hard plastic state.

The prefabricated box girder 2 is prefabricated by adopting reinforced concrete materials, and the concrete strength grade is C50, the length is 8m, the height is 1.5m, and the width is 24 m.

The bed-jig bottom plate 3 is formed by rolling a steel plate with the thickness of 10 mm.

The bed mould bottom stay bar 4 is composed of a screw rod with the diameter of 60mm and a bolt, and a stay bar top hinge 90 and a bottom plate bearing plate 9 are arranged at the top end of the screw rod. The stay bar top hinge 90 is a spherical hinge with the diameter of 60mm, and the bottom plate bearing plate 9 is formed by rolling a steel plate with the thickness of 2 mm.

The jig frame support columns 5 adopt H-shaped steel with the specification of 100 multiplied by 6 multiplied by 8, and column top support beams 17 are arranged at the top ends of the jig frame support columns 5 in the same row; the column-top supporting beam 17 is rolled by a steel plate with a thickness of 10mm, and has a width of 30cm and a height of 20 cm. A sliding beam sliding groove 18 is arranged on the column top supporting beam 17, and the width of the sliding beam sliding groove 18 is 10cm, and the height of the sliding beam sliding groove 18 is 8 cm.

The lower bed-jig plate 6 and the upper bed-jig plate 23 are both formed by rolling steel plates with the thickness of 2mm, a bed-jig plate position-adjusting hinge 92 is arranged at the joint of the connected lower bed-jig plate 6 or the connected upper bed-jig plate 23, and the bed-jig plate position-adjusting hinge 92 adopts a hinge with the diameter of a rotating shaft of 2 mm.

The stirrup limiting plate 7 is formed by rolling a steel plate with the thickness of 20mm, and the width of the stirrup limiting plate is 6 cm.

Spacing falcon 8 at the bottom of the board adopts the steel sheet rolling that thickness is 20mm to form, and its width is 10cm, and length is 20 cm.

The box girder buttress 10 is prefabricated by reinforced concrete materials, the concrete strength grade is C30, and the height is 300 mm.

The longitudinal rib limiting groove 14 is formed by rolling a steel plate with the thickness of 2mm, and is 3.5cm wide and 3.5cm high.

The bed plate slide beam 15 is formed by rolling a steel plate with the thickness of 2mm, and the width of the bed plate slide beam is 20cm, and the height of the bed plate slide beam is 10 cm.

The sliding beam connecting plate 16 is formed by rolling a steel plate with the thickness of 10mm, a sliding beam roller 89 is arranged at the lower part of the sliding beam connecting plate, and a universal ball wheel with the diameter of 30mm is adopted as the sliding beam roller 89.

The floor slings 19 are wire ropes of 30mm diameter.

The bed plate hanger rod 20 adopts a screw rod with the diameter of 60 mm.

The bed mould connecting ring 21 is a steel bar with the thickness of 10mm, and is rolled into a normally circular ring shape, and the diameter of the steel bar is 100 mm.

The bed plate connecting bolt 22 adopts a nut with the specification matched with the bed plate hanging rod 20.

The longitudinal rib limiting ring 24 is made of a steel pipe with the diameter of 50 mm.

The supporting beam position adjusting bolt 25 is composed of a screw rod and a bolt, wherein the diameter of the screw rod is 60 mm.

The platform support beam 26 is rolled by a steel plate with the thickness of 10mm, and the width of the platform support beam is 20 cm.

The suspension platform plate 27 is formed by rolling an iron sheet with the thickness of 2 mm.

The box girder steel reinforcement cage 28 includes the box girder stirrup 11 and the box girder longitudinal reinforcement 13, wherein the diameter of the box girder longitudinal reinforcement 13 is 25mm, and the diameter of the box girder stirrup 11 is 10 mm.

The plane of the hoisting connecting plate 29 is rectangular, is arranged parallel to the box girder longitudinal ribs 13, is formed by rolling a steel plate with the thickness of 10mm, has the width of 10cm and the length of 30cm, and is provided with a vertical hole for the hoisting screw 30 to pass through and a stirrup embedded groove 12 connected with the box girder stirrups 11. The stirrup embedded groove 12 is semicircular in section and 12mm in diameter. The hoisting screw 30 is a screw with the diameter of 30 mm;

the screw fastening bolt 31 is matched with the hoisting screw 30.

The template bottom supporting plate 32 is formed by rolling a steel plate with the thickness of 6 mm.

The template angle-adjusting bolt 33 is formed by rolling a high-strength screw rod with the diameter of 60 mm.

The template angle adjusting plate 34 is formed by rolling a steel plate with the thickness of 6 mm.

The adjusting support body 35 is formed by stacking steel plates with the thickness of 2mm into a step shape.

The formwork support 36 is made of H-shaped steel having a specification of 100 × 100 × 6 × 8.

The box girder bottom die 37, the box girder side die 38, the box girder inner die 47, the box girder top die 53 and the box girder end die 59 are all made of steel plates or alloy templates formed by rolling steel plates with the thickness of 3mm, and the steel bar position control devices 52 are arranged on the box girder bottom die 37 and the box girder inner die 47.

The steel bar position control device 52 comprises a position control support plate 98, a position control support plate 99 and a position adjusting

screw rod

100, and 3 sets of the position control support plate, the position control support plate and the position adjusting screw rod are respectively arranged on the box girder bottom die 37 and the box girder inner die 47 on the top layer. The position control support plate 98 is formed by rolling a steel plate with the thickness of 2mm, is cylindrical and has the height of 45mm, and a support plate airtight plate 101 is stuck to the outer side wall of the position control support plate along the annular direction. The cross section of the position control supporting plate 99 is U-shaped, is formed by rolling a steel plate with the thickness of 2mm, is welded with the box girder bottom die 37 or the box girder inner die 47, and is provided with a screw hole matched with the position adjusting screw rod 100. The positioning screw 100 is formed by rolling a screw rod with the thickness of 30mm, is vertically welded with the position control support plate 98 and is connected with the position control support plate 99 through threads, and the support plate airtight plate 101 is a rubber plate with the thickness of 2 mm.

The template connecting support plate 39 is formed by rolling a steel plate with the thickness of 10mm, and the width and the height of the template connecting support plate are 10cm and 10cm respectively.

The thickness of the side mould adjusting falcon 40 is the same as that of the side mould 38 of the box girder, the cross section of the side mould adjusting falcon is T-shaped, the height of the step is 1.5mm, and the length of the step is 30 mm.

The adjusting falcon pressing plate 41 is formed by rolling a steel plate with the thickness of 2 mm.

The side die connecting plate 42 is formed by rolling a steel plate with the thickness of 2 mm.

The connecting plate limiting groove 43 is formed by rolling a steel plate with the thickness of 2mm, the cross section of the connecting plate limiting groove is L-shaped, the height of the connecting plate limiting groove is 3mm, the width of the connecting plate limiting groove is 5cm, and the length of the connecting plate limiting groove is 10 cm.

The side die pressing rod 44 is made of a steel pipe with the diameter of 60mm and is connected with the side die connecting plate 42 in a welding mode.

The connecting plate positioning bolt 45 is formed by rolling a screw rod with the diameter of 30 mm.

The box girder inner die 47 comprises an inner die top plate 94, an inner die bottom plate 95 and an inner die side plate 96, which are rolled by steel plates with the thickness of 3 mm; the lower surface of the inner mold top plate 94 and the upper surface of the inner mold bottom plate 95 are provided with inner mold supporting grooves 49 which are opposite in mirror image, the inner mold supporting grooves 49 are formed by rolling steel plates with the thickness of 2mm, the width of the inner mold supporting grooves is 10cm, and the height of the inner mold supporting grooves is 4 cm. An inner die adjusting falcon 97 is arranged on the inner die side plate 96, the cross section of the inner die adjusting falcon 97 is in a T shape, the height of the step is 1.5mm, and the length of the step is 30 mm. A template rotating hinge 118 is arranged at the joint part of the inner mold bottom plate 95 and the inner mold side plate 96. The template rotary hinge 118 is a hinge with a rotating shaft diameter of 3 mm.

The inner supporting plate 48 is formed by rolling a steel plate with the thickness of 2mm, and the width of the inner supporting plate is 6 cm.

The first inner supporting rod 50 and the second inner supporting rod 51 are both composed of screws and bolts with the diameter of 30mm, and the fastening directions of the screws on the two sides of the bolts are opposite. The stay bar pivot hinge 117 is a spherical hinge with a diameter of 30 mm.

The gluten passing groove 54 has a width of 40mm and a height of 10 cm.

The top die top connecting plate 55 is formed by rolling a steel plate with the thickness of 10mm, is connected with the panel steel bar 46 through a bolt, and is provided with a top die side stay bar 56 on the upper surface. The panel reinforcing steel bars 46 are threaded ribbed reinforcing steel bars with the diameter of 25mm, and the top die side stay bars 56 are made of steel pipes with the diameter of 60 mm.

The top die connecting bolt 57 is formed by rolling a screw rod with the diameter of 30 mm.

The steam injection holes 58 have a diameter of 10 mm.

The template connecting bolt 60 is composed of a screw rod and a bolt with the diameter of 30 mm.

The intracavity water spray box 61 includes a water spray box inner box 106 and a water spray box outer box 107, and a shift roller 108 is provided on the lower surface of the intracavity water spray box 61. The inner water spraying box 106 is formed by rolling a steel plate with the thickness of 0.3mm, the outer water spraying box 107 is made of a rubber plate material with the thickness of 1mm, the cross section of the outer water spraying box is similar to that of the inner water spraying box 106, and the shifting roller 108 is a universal wheel with the diameter of 6 cm.

The position control rod 62 is made of a steel pipe with the diameter of 30 mm.

The box girder bottom plate 63 is formed by rolling a steel plate with the thickness of 10 mm.

The first water collecting groove plate 64 and the second water collecting groove plate 69 are both rolled into an upper concave groove shape by adopting steel plates with the thickness of 2mm, water leakage groove holes 109 are respectively arranged on the first water collecting groove plate 64 and the second water collecting groove plate 69, the lower surface of the water leakage groove plates is connected with the residual water collecting box 70, the residual water collecting box 70 is formed by rolling iron sheets with the thickness of 0.2mm, and the diameter of each water leakage groove hole 109 is 10 mm.

The transverse water spray pipe 65 and the inclined water spray pipe 66 are both made of steel pipes with the inner diameter of 30mm, a water spray pipe rotating hinge 116 is arranged at the joint of the inclined water spray pipe 66 and the transverse water spray pipe 65, and the inclined water spray pipe 66 and the transverse water spray pipe 65 are communicated with an outside-cavity water supply pipe 119. Wherein, the water spray pipe rotary hinge 116 adopts a spherical hinge with the diameter of 30mm, and the water supply pipe 119 outside the cavity adopts a steel pipe with the inner diameter of 30 mm.

The sliding support column 67 is formed by rolling H-shaped steel with the specification of 100 multiplied by 6 multiplied by 8, the top end of the sliding support column is vertically welded with the transverse water spray pipe 65, the bottom end of the sliding support column is vertically welded with the sliding bottom plate 115, the bottom plate roller 76 is arranged between the sliding bottom plate 115 and the beam yard foundation 1, and the sliding bottom plate 115 is formed by rolling steel plates with the thickness of 10 mm; the bottom plate rollers 76 are universal wheels with a diameter of 10 cm.

The first positioning transverse bolt 68 and the second positioning transverse bolt 84 are both composed of screws and bolts with the diameter of 60mm, and the fastening directions of the screws on the two sides of the bolts are opposite; one end of the first position-adjusting transverse bolt 68 is vertically welded with the sliding support column 67, the other end is connected with the inclined water spraying pipe 66 through a position-adjusting bolt rotating hinge 111, and the position-adjusting bolt rotating hinge 111 adopts a spherical hinge with the diameter of 60 mm.

Both the intracavity spray head 71 and the extraluminal spray head 72 adopt high-pressure water pipe spray heads.

The maintenance pillars 73 and the pillar beams 74 are each rolled from H-shaped steel having a gauge of 100 × 100 × 6 × 8.

The post cross beam 74 is connected with the rain-proof curtain cloth 78 in a sticking way, and the rain-proof curtain cloth 78 adopts a geomembrane with the thickness of 1 mm.

The pillar base plate 75 is rolled from a steel plate having a thickness of 10 mm.

The arc-shaped supporting beam 77, the steam-cured cross beam 79 and the steam-cured inclined strut 80 are all formed by rolling steel pipes with the diameter of 100 mm.

The beam position adjusting bolt 82 is formed by rolling a screw rod with the diameter of 30 mm.

A position control transverse plate 91 is arranged at the bottom end of the steam-curing inclined strut 80, and a bottom plate compacting bolt 85 is arranged on the position control transverse plate 91. The position control transverse plate 91 is formed by rolling a steel plate with the thickness of 10mm and is connected with the steam-cured inclined strut 80 in a welding mode.

The inclined strut rotating hinge 81 adopts a spherical hinge with the diameter of 100 mm.

The elastic control body 83 is made of a spring material with the diameter of 30cm through rolling.

The bottom plate compacting bolt 85 is formed by rolling a screw rod with the diameter of 30mm and is connected with the position control transverse plate 91 through a screw.

The maintenance steam-jet pipe 87 is a steel pipe with the diameter of 30mm or a steel pipe with one end closed and the other end communicated with external steam supply equipment, and a steam jet hole 58 is arranged on the pipe wall of the maintenance steam-jet pipe 87.

The steam-cured curtain cloth 88 is made of a geomembrane with the thickness of 1mm, a closed bottom plate 86 is arranged at the joint of the bottom end of the steam-cured curtain cloth and the bottom beam field base 1, and the closed bottom plate 86 is made of a rubber plate with the thickness of 2mm and is arranged in the length direction of the steam-cured curtain cloth 88.

The top die connecting plate 93 is formed by rolling a steel plate with the thickness of 10 mm.

The inner mold position control column 102 is formed by rolling a steel plate having a thickness of 2mm, and is disposed inside the box girder inner mold 47 so as to extend in the longitudinal direction.

The cross section of the pipeline through hole 103 is circular, the diameter is 80mm, and the inner side wall of the pipeline through hole is provided with a pipeline closed ring 104. The pipeline closed ring 104 is formed by sewing a geomembrane with the thickness of 1mm into a circular ring shape, the diameter of the circular ring is 20mm, the circular ring is connected with the inner side wall of the pipeline penetrating hole 103 in an adhering mode, a closed control pipe 105 is arranged, and the closed control pipe 105 is a rubber pipe with the diameter of 10 mm.

The diameter of the water leakage slot 109 is 50 mm.

The fixed support plate 110 is formed by rolling a steel plate with the thickness of 10mm, the width of the fixed support plate is 20cm, the fixed support plate is arranged in parallel to the second water collecting groove plate 69, and an elastic control body 83 and a closed pressing plate 112 are sequentially arranged on the fixed support plate; the elastic control body 83 adopts a spring with the diameter of 20 mm; the sealing press plate 112 is a rubber plate with a thickness of 2 mm.

The outer box partition 113 is formed by cutting a rubber plate having a thickness of 2 mm.

The intracavity water supply pipe 114 and the extracavity water supply pipe 119 are respectively made of PVC pipes having diameters of 60mm and 100 mm.

Claims

1. The construction method of the prefabricated box girder is characterized in that: the method comprises the following construction steps:

1) construction preparation: reinforcing the beam field foundation (1), and arranging a box girder buttress (10) on the beam field foundation (1); determining the mixing proportion of concrete; preparing a device required by construction;

2) binding a reinforcement cage: two rows of bed plate bottom support rods (4) and two rows of bed frame support columns (5) are arranged on the bed frame bottom plate (3); the outer side wall of the lower bed mould plate (6) is provided with a stirrup limiting plate (7) and a plate bottom limiting tenon (8), then the lower bed mould plate (6) is hoisted to the bed mould frame bottom plate (3), a bottom plate pressure bearing plate (9) is connected with the plate bottom limiting tenon (8) on the lower surface of the lower bed mould plate (6), and the inclination angle of the lower bed mould plate (6) is adjusted through a bed mould bottom support rod (4); firstly, placing the box girder stirrups (11) on the lower layer in the stirrup embedded grooves (12), then placing the box girder longitudinal reinforcements (13) on the lower layer in the longitudinal reinforcement limiting grooves (14), and finishing the binding construction of the box girder longitudinal reinforcements (13) on the lower layer and the box girder stirrups (11); firstly, embedding a sliding beam connecting plate (16) at the lower part of a bed plate sliding beam (15) into a sliding beam sliding groove (18) of a column top supporting beam (17), then respectively connecting a bed plate sling (19) and a bed plate suspender (20) with a bed plate connecting ring (21) and a bed plate connecting bolt (22), controlling the spatial position of an upper bed plate (23) through the bed plate sling (19) and the bed plate suspender (20), then sliding the upper bed plate (23) to the upper part of a lower bed plate (6), and enabling a box beam longitudinal rib (13) at the upper layer to pass through a longitudinal rib limiting ring (24); a supporting beam positioning bolt (25) is arranged on the upper surface of the upper-layer bed plate (23), and a platform supporting beam (26) and a suspended platform plate (27) are sequentially arranged at the top end of the supporting beam positioning bolt (25); binding construction of a box girder reinforcement cage (28) is carried out on the suspension platform plate (27); the side wall of the lower bed mould plate (6) facing the upper bed mould plate (23) is provided with a longitudinal rib limiting groove (14); the side wall of the upper layer tire plate (23) facing the lower layer tire plate (6) is provided with a longitudinal rib limiting ring (24), and the other side wall is provided with a tire plate connecting ring (21) and a tire plate connecting bolt (22); the stirrup limiting plate (7) is provided with a stirrup embedded groove (12);

3) hoisting construction of a box girder steel reinforcement cage (28): removing the upper layer of the bed plate (23) and releasing the restraint of the bed plate sling (19) and the bed plate hanger rod (20) on the upper layer of the bed plate (23); firstly, arranging a hoisting connecting plate (29) at the lower part of the box girder steel reinforcement cage (28), then enabling a hoisting screw (30) to penetrate through a gap of the box girder steel reinforcement cage (28), and then enabling the hoisting screw (30) and the hoisting connecting plate (29) to be firmly connected through a screw fastening bolt (31); the plane of the hoisting connecting plate (29) is rectangular and is arranged parallel to the box girder longitudinal ribs (13), the hoisting connecting plate (29) is formed by rolling a steel plate, and vertical holes for the hoisting screws (30) to pass through and stirrup embedded grooves (12) connected with the box girder stirrups (11) are arranged on the hoisting connecting plate;

4) erecting a box girder template: after the inclination angle of the template angle adjusting plate (34) is adjusted through the template angle adjusting bolt (33) on the template bottom supporting plate (32), an adjusting support body (35) is arranged in a gap between the template bottom supporting plate (32) and the template angle adjusting plate (34), and stable support is provided for the template angle adjusting plate (34); firstly, arranging a template supporting body (36) on the top surface of a template angle adjusting plate (34), then synchronously hoisting a box girder bottom die (37) and box girder side dies (38) onto the template supporting body (36), and arranging side die adjusting tenons (40) at joints of the box girder side dies (38); an adjusting falcon pressing plate (41) is arranged on the outer side wall of the side-form adjusting falcon (40), and the adjusting falcon pressing plate (41) is firmly connected with the side form (38) of the box girder through bolts; inserting the side die connecting plate (42) into the connecting plate limiting groove (43), controlling the inclination angle of the side die (38) of the box girder through the side die pressing rod (44), and firmly connecting the connecting plate limiting groove (43) with the side die connecting plate (42) by adopting a connecting plate positioning bolt (45); integrally hoisting a box girder reinforcement cage (28) formed by binding box girder stirrups (11), box girder longitudinal reinforcements (13) and panel reinforcements (46) to the upper parts of a box girder bottom die (37) and box girder side dies (38); the box girder inner mold (47) is arranged inside the box girder steel reinforcement cage (28) in a penetrating way along the direction parallel to the box girder longitudinal ribs (13), and an inner mold supporting plate (48) is embedded into an inner mold supporting groove (49); respectively applying top pressure to the box girder inner mold (47) through a first inner mold stay bar (50) and a second inner mold stay bar (51) to correct the spatial position of the box girder inner mold (47); the position of the box girder reinforcement cage (28) is controlled by a reinforcement position control device (52); connecting a box girder top die (53) with the top of a box girder side die (38), and enabling a panel steel bar (46) to penetrate through a gluten through groove (54); a top die top connecting plate (55) is arranged on the panel steel bar (46); synchronously limiting the transverse position of the box girder top die (53) through a top die side supporting rod (56) on a top die top connecting plate (55) and a top die connecting bolt (57); placing a box girder end mold (59) at the outer sides of a box girder bottom mold (37) and a box girder inner mold (47), and firmly connecting the box girder bottom mold (37), the box girder side mold (38), the box girder top mold (53) and the box girder inner mold (47) with the box girder end mold (59) through a template connecting bolt (60);

5) and (3) concrete pouring construction: pouring concrete into a cavity formed by enclosing a box girder bottom die (37), a box girder side die (38), a box girder top die (53) and a box girder inner die (47) by adopting concrete pouring equipment to form a prefabricated box girder (2);

6) steam curing of the prefabricated box girder: arranging a strut beam (74) at the top end of the maintenance strut (73) which is transversely opposite, arranging strut bottom plates (75) at the bottom end of the maintenance strut (73) respectively, and arranging bottom plate rollers (76) between the strut bottom plates (75) and the beam field foundation (1); arc-shaped supporting beams (77) with arc-shaped planes are arranged at the upper parts of the pillar cross beams (74), and rainproof curtain cloth (78) is arranged between the adjacent arc-shaped supporting beams (77); two sides of the steam-curing cross beam (79) are respectively provided with a steam-curing inclined strut (80), and an inclined strut rotating hinge (81) is arranged at the joint of the steam-curing cross beam (79) and the steam-curing inclined strut (80); a beam position adjusting bolt (82) on the upper surface of the steam-curing beam (79) is connected with the pillar beam (74), and an elastic position control body (83) is arranged between the pillar beam (74) and the steam-curing beam (79); the maintenance support column (73), and a steam-curing cross beam (79) and a steam-curing inclined strut (80) which are connected with the maintenance support column (73) and the support cross beam (74) into a whole through external traction equipment move to a set position along the length direction of the precast box girder (2); firstly, adjusting the inclination angle of the steam-curing inclined strut (80) through a second position-adjusting transverse bolt (84), then adjusting the elevation of a steam-curing cross beam (79) through a cross beam position-adjusting bolt (82), and then firmly connecting a closed bottom plate (86) with a beam yard foundation (1) through a bottom plate compaction bolt (85); inserting a steam curing steam injection pipe (87) into a cavity formed by enclosing the steam curing curtain cloth (88) and the precast box girder (2) along the direction parallel to the precast box girder (2), communicating external steam supply equipment with the steam curing steam injection pipe (87), and performing steam curing on the precast box girder (2);

7) and (3) water spraying maintenance of the prefabricated box girder: firstly, placing a prefabricated box girder (2) on a box girder buttress (10), and then placing a water spraying box (61) in a cavity inside the prefabricated box girder (2); the position of the water spraying box (61) in the cavity is controlled in the prefabricated box girder (2) through a position control rod (62), and the outer side wall of a box girder bottom plate (63) is connected with a first water collecting groove plate (64); a sliding support column (67) connected with the transverse water spray pipe (65) and the inclined water spray pipe (66) is moved to a set position through an external traction device, and the inclination angle of the inclined water spray pipe (66) is adjusted through a first position-adjusting transverse bolt (68); a second water collecting groove plate (69) is arranged at the lower part of the prefabricated box girder (2); collecting the redundant curing water through a residual water collecting box (70) below the first water collecting groove plate (64) and the second water collecting groove plate (69); and synchronously spraying water to the precast box girder (2) through the intracavity spray head (71) and the extraluminal spray head (72) to perform water spraying maintenance of the precast box girder (2).

2. The construction method of the precast box girder according to claim 1, wherein: step 2), rolling the jig frame support columns (5) by using section steel columns or steel pipes, and placing column top support beams (17) at the top ends of the jig frame support columns (5) in the same row; the column top supporting beam (17) is formed by rolling a steel plate, and a sliding beam sliding groove (18) connected with a sliding beam connecting plate (16) is arranged on the column top supporting beam; the lower part of the sliding beam connecting plate (16) is provided with a sliding beam roller (89); the bed mould bottom stay bar (4) is formed by combining a screw rod and a bolt, and a stay bar top hinge (90) and a bottom plate bearing plate (9) are arranged at the top end of the screw rod; the lower-layer tire plate (6) and the upper-layer tire plate (23) are both formed by rolling steel plates or aluminum alloy templates, and tire plate position adjusting hinges (92) are arranged at the joints of the connected lower-layer tire plates (6) or the connected upper-layer tire plates (23).

3. The construction method of the precast box girder according to claim 1, wherein: step 4), the template supporting body (36) is formed by rolling profile steel and is arranged in a direction parallel to the longitudinal ribs (13) of the box girder; the thickness of the side die adjusting falcon (40) is the same as that of the side die (38) of the box girder, and the cross section of the side die adjusting falcon (40) is in a T shape; the box girder bottom die (37), the box girder side die (38), the box girder inner die (47) and the box girder top die (53) are all made of steel plates or alloy templates, and reinforcing steel bar position control devices (52) are arranged on the box girder bottom die (37) and the box girder inner die (47); the lower surface of the bottom box beam mould (37) is provided with a connecting plate limiting groove (43), and the top box beam mould (53) is provided with a hole for a top mould connecting bolt (57) to pass through; a top die connecting plate (93) and a top die connecting bolt (57) are arranged at the top of the box girder side die (38), and the top die connecting bolt (57) is vertically welded and connected with the top die connecting plate (93); the box girder inner die (47) comprises an inner die top plate (94), an inner die bottom plate (95) and an inner die side plate (96), inner die supporting grooves (49) with mirror images opposite to each other are formed in the lower surface of the inner die top plate (94) and the upper surface of the inner die bottom plate (95), an inner die adjusting falcon (97) is arranged on the inner die side plate (96), and a template rotating hinge (118) is arranged at the connecting part of the inner die bottom plate (95) and the inner die side plate (96); template connecting support plates (39) are respectively arranged on the outer side walls of the inner mold bottom plate (95) and the box girder bottom mold (37); the thickness of the inner die adjusting falcon (97) is the same as that of the inner die top plate (94), and the cross section of the inner die adjusting falcon (97) is in a T shape; the steel bar position control device (52) comprises a position control support plate (98), a position control support plate (99) and a position adjusting screw rod (100), and 2-4 sets of steel bar position control devices (52) are respectively arranged on the box girder bottom die (37) and the box girder inner die (47) on the top layer; the positioning screw rod (100) is formed by rolling a screw rod, the positioning screw rod (100) is vertically welded or connected with the position control support plate (98) through threads, and the positioning screw rod (100) is connected with the position control support plate (99) through threads; the cross section of the position control supporting plate (99) is U-shaped and is formed by rolling a steel plate, and the position control supporting plate (99) is welded with the box girder bottom die (37) or the box girder inner die (47); the position control support plate (98) is formed by rolling a steel plate and is cylindrical, the height of the position control support plate (98) is 10-20 mm greater than the thickness of the steel bar protective layer, and a support plate sealing plate (101) is adhered to the outer side wall of the position control support plate in the circumferential direction; the top die top connecting plate (55) is formed by rolling a steel plate and is connected with the panel steel bar (46) through a bolt, and a top die side stay bar (56) is arranged on the upper surface of the top die top connecting plate; the first inner mold stay bar (50) and the second inner mold stay bar (51) are formed by combining screws and bolts, and the fastening directions of the screws on the two sides of the bolts are opposite; two ends of the first inner die supporting rod (50) are respectively connected with the inner die supporting plate (48) and the inner die position control column (102) in a vertical welding mode or in a threaded mode; both ends of the second inner die supporting rod (51) are connected with the adjusting falcon pressing plate (41) and the inner die position control column (102) through supporting rod rotating hinges (117); the inner mould position control column (102) is formed by rolling a steel plate or profile steel and is arranged inside the box girder inner mould (47) along the length direction; the box girder end die (59) is provided with a channel connected with the box girder bottom die (37), the box girder side die (38), the box girder top die (53) and the box girder inner die (47), and a pipeline through hole (103) is arranged at a position corresponding to a preset pipeline; the cross section of the pipeline through hole (103) is circular, and a pipeline sealing ring (104) is arranged on the inner side wall of the pipeline through hole; the pipeline sealing ring (104) is formed by sewing a geomembrane or a rubber sheet and is adhered and connected with the inner side wall of the pipeline penetrating hole (103), and the pipeline sealing ring (104) is provided with a sealing control pipe (105).

4. The construction method of the precast box girder according to claim 1, wherein: step 7), the intracavity water spraying box (61) comprises a water spraying box inner box (106) and a water spraying box outer box (107), and a shifting roller (108) is arranged on the lower surface of the intracavity water spraying box (61); the inner water spraying box (106) is formed by rolling a steel plate, the outer water spraying box (107) is made of a rubber plate or a PVC plate material, and the outer side wall of the outer water spraying box (107) is provided with an intracavity spray head (71); the first water collecting channel plate (64) and the second water collecting channel plate (69) are both rolled into an upper concave channel structure by adopting steel plates, water leakage slotted holes (109) are formed in the first water collecting channel plate (64) and the second water collecting channel plate (69), and the lower surfaces of the first water collecting channel plate (64) and the second water collecting channel plate (69) are connected with a residual water collecting box (70); one side of the second water collecting groove plate (69) is connected with the sliding support column (67), and the other side is provided with a fixed support plate (110); the fixed support plate (110) is arranged in parallel to the second water collecting groove plate (69), and an elastic control body (83) and a closed pressing plate (112) are sequentially arranged on the fixed support plate; an outer box clapboard (113) and an intracavity water supply pipe (114) are arranged between the inner box (106) of the water spraying box and the outer box (107) of the water spraying box; the sliding support column (67) is formed by rolling steel pipes or section steel, the top end of the sliding support column is vertically welded with the transverse water spray pipe (65), the bottom end of the sliding support column is vertically welded with the sliding bottom plate (115), and a bottom plate roller (76) is arranged between the sliding bottom plate (115) and the beam yard foundation (1); the first positioning transverse bolt (68) comprises a screw rod and a bolt, the fastening directions of the screw rods on the two sides of the bolt are opposite, one end of the first positioning transverse bolt (68) is vertically welded and connected with the sliding support column (67), and the other end of the first positioning transverse bolt is connected with the inclined water spray pipe (66) through a positioning bolt rotating hinge (111); the transverse water spray pipe (65) and the inclined water spray pipe (66) are formed by rolling steel pipes, a water spray pipe rotating hinge (116) is arranged at the joint of the inclined water spray pipe (66) and the transverse water spray pipe (65), and the inclined water spray pipe (66) and the transverse water spray pipe (65) are communicated with the water supply pipe (119) outside the cavity; the transverse water spray pipe (65) and the inclined water spray pipe (66) are respectively communicated with an external water supply pipe, and an outer cavity spray head (72) is arranged on the side wall of the transverse water spray pipe (65) and the side wall of the inclined water spray pipe (66) facing the prefabricated box girder (2).

5. The construction method of the precast box girder according to claim 1, wherein: step 6), the pillar beam (74) is formed by rolling steel pipes or section steel and is connected with the rainproof cord fabric (78) in a sticking way or through screws; the rainproof curtain cloth (78) is formed by cutting a geomembrane or a rubber sheet; the steam-curing cross beam (79) is formed by rolling a steel pipe or profile steel, and the upper surface of the steam-curing cross beam is vertically welded and connected with the cross beam positioning bolt (82); the cross beam position adjusting bolt (82) is formed by rolling a screw; the elastic control body (83) is formed by rolling a spring material, and the bottom end of the elastic control body is welded with the steam-curing beam (79); the steam-curing inclined strut (80) is formed by rolling a steel pipe or section steel, a second position-adjusting transverse bolt (84) is arranged on the side, away from the precast box beam (2), of the side wall of the steam-curing inclined strut, the second position-adjusting transverse bolt (84) is connected with the steam-curing inclined strut (80) through a position-adjusting bolt rotating hinge (111), a position-controlling transverse plate (91) is arranged at the bottom end of the steam-curing inclined strut (80), and a bottom plate compacting bolt (85) is arranged on the position-controlling transverse plate (91); the bottom plate compaction bolt (85) is connected with the position control transverse plate (91) through a screw; the steam-curing cross beams (79) and the steam-curing inclined struts (80) are arranged for 2-4 times along the length direction of the precast box beam (2), and sealed steam-curing curtain cloth (88) is arranged between the adjacent steam-curing cross beams (79) and between the adjacent steam-curing inclined struts (80); the steam-cured curtain cloth (88) adopts a geomembrane, and a closed bottom plate (86) is arranged at the joint of the bottom end of the steam-cured curtain cloth and the beam yard foundation (1); the closed bottom plate (86) is a rubber plate and is arranged in a whole length direction along the length direction of the steam-cured curtain cloth (88); the maintenance steam injection pipe (87) is a steel pipe or a PVC pipe, one end of the maintenance steam injection pipe is closed, the other end of the maintenance steam injection pipe is communicated with external steam supply equipment, and a steam injection hole (58) is formed in the pipe wall of the maintenance steam injection pipe (87).