CN117733994A - Steel template capable of being partially detached from end part of prefabricated long box girder - Google Patents

Abstract

The invention discloses a steel template with partially-detachable end parts of a prefabricated long box girder, which belongs to the technical field of precast concrete girder production, wherein a bottom die strip in a range of D, which is close to the end part in the bridge direction, is provided with a downward unloading mechanism, a side die block in a range of H, which is close to the bottom in the vertical direction, is provided with an outward unloading mechanism, and a height difference with a value of H can be formed among the unloaded bottom die strip, the surface of the side die block and the surface of an outer layer die plate. The using method comprises the following steps: after pouring of the concrete is completed, before the prestressed steel beam is stretched, the end part of the outer layer template has preset unloading behavior, so that the contact surface provided by the outer layer template can be effectively adapted to the upward deflection of the beam body after the prestressed steel beam is stretched in advance, the phenomena of concentrated stress and obvious friction effect of the end part of the beam body are effectively improved, and the problem that the edge of the end bottom plate generates cracks when the long box beam is prefabricated is fundamentally solved.

Description

Steel template capable of being partially detached from end part of prefabricated long box girder

Technical Field

The invention belongs to the technical field of precast concrete beam production, and particularly relates to a steel template with partially-detachable end parts of a precast long box beam.

Background

Along with popularization and popularization of advanced construction concepts such as standardization, industrialization and the like, the construction of the high-speed railway bridge has been advanced into a new stage. The upper structure form is gradually transited from a more common 32m beam type to a 40m beam type, and along with the increase of the length and the self weight of the beam body, the precast beam body encounters a certain quality problem during construction production, wherein the problem that the edge of the bottom plate at the end part of the box beam, particularly 40m, is cracked is more prominent.

The root cause of the quality problems described above arises: as shown in fig. 9, after the beam body concrete is poured and the prestressed steel bundles are tensioned, the beam body is bent upwards (inverted arch), so that the stress concentration phenomenon of the edge of the end bottom plate is obvious, the friction effect is obvious, and the tensile stress exceeding the tensile strength of the beam body is generated, so that the concrete in the relevant area is pulled to crack.

Disclosure of Invention

Therefore, the invention aims to provide the steel template with partially-detachable end parts of the prefabricated long box girder, and the phenomena of concentrated stress and obvious friction effect of the end parts of the girder body are improved.

In order to achieve the above purpose, the present invention provides the following technical solutions:

the invention comprises an outer layer template supporting the outer side of the bottom surface of a box girder, wherein a truncated groove is formed in the outer layer template along the bottom end edge along the bridge direction, a bottom die bar for discharging force downwards vertically and side modules for discharging force to two sides are arranged at the truncated groove, and after concrete pouring is completed, the bottom die bar and the side modules are moved before the prestressed steel bundles are tensioned, so that the bottom edges at the two ends of the box girder are subjected to force discharging.

Further, a plurality of limit baffles are respectively arranged on the outer sides of edges of the bottom die strips and the side modules, which are close to the outer layer template, so that the inner sides of the bottom die strips and the side modules are flush with the inner sides of the outer layer template.

Further, the outside of die block strip has set firmly a plurality of die block back edges, the outside of side module has set firmly a plurality of side form cushion, the cut-off position department of outer template is equipped with unloads the power supporting part, it supports respectively in die block back edge and side form cushion position to unload the power supporting part.

Further, unload power supporting portion includes two supporting boards that set up side by side, supporting board one end is fixed the outer template outside, and one end suspension is in the cut-off outside, set firmly a plurality of fastening nuts between two supporting boards, threaded connection has fastening screw on the fastening nut, fastening screw supports respectively on side form cushion and the die block back of body are stupefied.

Further, the force unloading bearing part comprises a supporting bar which is distributed along the outer sides of the bottom die bar and the side die block, and two ends of the supporting bar are fixed at two ends of a truncated groove of the outer die plate through connecting pieces; two long slide bars and two short slide bars are arranged in the support bar in a sliding manner, the two long slide bars are positioned outside the bottom die bar, the two short slide bars are positioned outside the side die block, a plurality of inclined grooves are formed in one sides of the long slide bars and the short slide bars, which face the outer die plate, respectively, a plurality of supporting columns are vertically arranged on the side faces of the support bar, which face the outer die plate, in a sliding manner, the bottom ends of the supporting columns are supported at the positions of the inclined grooves, and the top ends of the supporting columns are respectively supported on the side die cushion blocks and the bottom die back edges; the vertical slip between two long slide bar is equipped with a trapezoidal piece, two long slide bar supports trapezoidal piece both sides face to one side, the support bar still threaded connection has a force-unloading double-screw bolt, force-unloading double-screw bolt one end supports trapezoidal piece bottom, the other end is followed the support bar outside stretches out, the intercommunication has the oil duct of buckling between long slide bar and the short slide bar, the oil duct intussuseption is filled with hydraulic oil.

Further, two ends of the oil duct are provided with straight section channels, the ends of the long slide bar and the short slide bar are provided with piston heads, and the piston heads are slidably arranged in the straight section channels.

Further, a horizontal sliding rail is fixedly arranged on the outer side of the supporting bar, a moving vehicle is arranged on the sliding rail in a sliding mode, a guide rail perpendicular to the end face of the poured box girder is arranged on the moving vehicle, a processing vehicle is arranged on the guide rail in a sliding mode, a polishing roller is rotatably arranged on the processing vehicle, the axis of the polishing roller is perpendicular to the end face of the poured box girder, and the upper side of the polishing roller is tangent to the bottom side face of the poured box girder.

The invention has the beneficial effects that:

the bottom die strip in the range of D, which is close to the end along the bridge direction, is provided with a downward unloading mechanism, the side die block in the range of H, which is close to the bottom along the vertical direction, is provided with an outward unloading mechanism, and the unloaded bottom die strip, the surface of the side die block and the surface of the outer layer die plate can form a height difference with the value of H. The using method comprises the following steps: after pouring of the concrete is completed, before the prestressed steel beam is stretched, the end part of the outer layer template has preset unloading behavior, so that the contact surface provided by the outer layer template can be adapted to the upward deflection of the beam body after the prestressed steel beam is stretched in advance, the phenomena of concentrated stress and obvious friction effect of the bottom end edge of the end part of the beam body are effectively improved, and the problem that the bottom end edge of the end part generates cracks during prefabrication of the long box beam is fundamentally solved.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and other advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out in the specification.

Drawings

In order to make the objects, technical solutions and advantageous effects of the present invention more clear, the present invention provides the following drawings for description:

FIG. 1 is a schematic view of an outer form according to an embodiment of the present invention;

FIG. 2 is a schematic view of a force-unloading bearing part according to an embodiment of the present invention;

FIG. 3 is a schematic diagram illustrating the force release of an outer form according to an embodiment of the present invention;

FIG. 4 is a schematic view of an outer form structure according to an embodiment of the present invention;

FIG. 5 is an enlarged schematic view of FIG. 4 at A;

FIG. 6 is a cross-sectional view of a second force-releasing retainer portion according to an embodiment of the present invention;

FIG. 7 is an enlarged schematic view of FIG. 6 at B;

FIG. 8 is an enlarged schematic view at C of FIG. 6;

FIG. 9 is a schematic view showing the upwarp of a tensioned preform;

the figures are marked as follows: 1. an outer layer template; 2. cutting a groove; 3. a bottom die strip; 31. bottom die back edges; 4. a side module; 41. a side die cushion block; 5. a limit baffle; 6. a force-unloading bearing part; 611. a bearing plate; 612. a fastening nut; 613. fastening a screw; 621. a support bar; 622. a long slide bar; 623. a short slide bar; 624. a chute; 625. abutting the column; 626. a trapezoid block; 627. a force-unloading stud; 628. an oil passage; 629. a piston head; 71. a slide rail; 72. a moving vehicle; 73. a guide rail; 74. machining the vehicle; 75. and (5) grinding the roller.

Detailed Description

As shown in fig. 1 to 8, the invention discloses a steel template with partially-detachable end part of a prefabricated long box girder, wherein the steel template of the box girder consists of an outer layer template 1, an inner layer template and an end part template, and forms a sealed box girder pouring structure, which is the prior art and is not described in redundant ways;

example 1

As shown in fig. 1, fig. 2 and fig. 3, a short-distance intercepting groove 2 is formed in the outer layer formwork 1 along the bottom end edge along the bridge direction, the intercepting groove 2 depth D is 5-20 cm, the intercepting groove 2 height H is 25-50 cm, the intercepting groove 2 is provided with a bottom die strip 3 which is vertically unloaded downwards and side modules 4 which are unloaded towards two sides, the bottom die strip 3 and the side modules 4 are blocked at the intercepting groove 2 to enable the outer layer formwork 1 to be closed, referring to fig. 3, after concrete pouring is completed, before the prestressed steel beam is tensioned, the bottom die strip 3 and the side modules 4 are moved, the unloading force can be completed at the bottom edge positions of two ends of the box girder, the unloading height H of the bottom die strip 3 and the side modules 4 can be 1-20 mm, the bottom die strip 3 and the side modules 4 which generate unloading actions have a reset mechanism, the position state before unloading can be restored, and the bearing capacity is not reduced because of the unloading mechanism.

In a further scheme, as shown in fig. 2, the outer sides of the edges of the bottom die strips 3 and the side modules 4, which are close to the outer layer template 1, are respectively provided with a plurality of limit baffles 5, so that the inner sides of the bottom die strips 3 and the side modules 4 are flush with the inner sides of the outer layer template 1, and the structure can also effectively inhibit the upward direction of the bottom die strips 3 from exceeding the surface of the outer layer template 1 and inhibit the side modules 4 from exceeding the surface of the outer layer template 1 from the outer side to the inner side.

In a further scheme, as shown in fig. 2, two side-by-side bottom die back edges 31 are fixedly arranged on the outer side of the bottom die strip 3, wherein the bottom die back edges 31 can be made of work steel, channel steel or other profile steel rod pieces meeting the stress requirement; the outside of side module 4 has set firmly two side form cushion blocks 41, and the distance between the side form cushion blocks 41 is the same with the distance between the bottom die back of body stupefied 31, the kerf 2 position department of outer template 1 is equipped with unloads power supporting part 6, it includes two supporting plates 611 that set up side by side to unload power supporting part 6, supporting plate 611 one end is fixed outer template 1 outside, one end suspension is in kerf 2 outsides, has set firmly a plurality of fastening nuts 612 between two supporting plates 611, threaded connection has fastening screw 613 on the fastening screw 612, fastening screw 613 supports respectively on side form cushion block 41 and the bottom die back of body stupefied 31.

In this embodiment, the bottom die strip 3 in the range of width D near the end along the bridge direction has a downward drop mechanism, the side die block 4 in the range of height H near the bottom along the vertical direction has an outward drop mechanism, and a height difference with value H can be formed between the surface of the bottom die strip 3, the surface of the side die block 4 and the surface of the outer die plate 1 after drop. The using method comprises the following steps: after pouring of the concrete is completed, before the prestressed steel beam is stretched, the end part of the outer layer template 1 has preset unloading behavior, so that the contact surface provided by the outer layer template can be adapted to the upward deflection of the beam body after the prestressed steel beam is stretched in advance, the phenomena of concentrated stress and obvious friction effect of the edge of the bottom plate of the end part of the beam body are effectively improved, and the problem of edge cracking of the bottom plate of the end part during prefabrication of the long box beam is fundamentally solved; the working principle of the technical scheme of the embodiment is clear, the division of the area modules is reasonable, the supporting mode of the prefabricated beam in different procedures such as concrete pouring, prestress beam tensioning and the like can be effectively changed, the stress state of the beam body is reasonable, and the problem of crack quality is avoided; the technical scheme skillfully reforms the traditional template scheme, so that better social benefits are obtained, and meanwhile, the required economic cost is lower; and the structure is simple to operate and convenient to construct, and the recycling of all template appliances is realized through the structures of the fastening nuts 612 and the fastening bolts, so that the structure accords with the safe and green sustainable development concept.

Example two

As shown in fig. 4 to 8, further improvement is made on the basis of the first embodiment:

the structure of the unloading bearing part is shown in fig. 6 and 7, the unloading bearing part 6 comprises a supporting bar 621 distributed along the outer sides of the bottom die bar 3 and the side die block 4, the middle part of the supporting bar 621 is horizontal, the two ends of the supporting bar 621 are tilted upwards, and the two ends of the supporting bar 621 are fixed at the two ends of the truncated groove 2 of the outer die plate 1 through connecting pieces; two long slide bars 622 and two short slide bars 623 are arranged in the support bar 621 in a sliding manner, the two long slide bars 622 are positioned outside the bottom die bar 3, the two short slide bars 623 are positioned outside the side die block 4, a plurality of inclined grooves 624 are formed in one side of the long slide bars 622 and the short slide bars 623, which face the outer die plate 1, a plurality of support columns 625 are arranged on the side face of the support bar 621, which faces the outer die plate 1, in a vertical sliding manner, the bottom ends of the support columns 625 are propped against the inclined grooves 624, and the top ends of the support columns 625 are respectively propped against the side die cushion blocks 41 and the bottom die back edges 31; a trapezoid block 626 is vertically arranged between the long slide bars 622 in a sliding mode, the long slide bars 622 are propped against two inclined side faces of the trapezoid block 626, the supporting bar 621 is further connected with a force unloading stud 627 in a threaded mode, one end of the force unloading stud 627 is propped against the bottom of the trapezoid block 626, the other end of the force unloading stud 627 extends out of the supporting bar 621, a bent oil duct 628 is communicated between the long slide bars 622 and the short slide bars 623, two ends of the oil duct 628 are straight-section channels, piston heads 629 are arranged at the end portions of the long slide bars 622 and the short slide bars 623 in a sliding mode, and hydraulic oil is filled in the oil duct 628.

In this structure, under the compression of the end of the box girder, a plurality of supporting columns 625 supporting the bottom die bar 3 and the side die plate are pressed at the same time, so that the supporting columns 625 move downwards and outwards and move along the chute 624, under the collision of the supporting columns 625, the short sliding bars 623 and the long sliding bars 622 simultaneously perform the same displacement, when the short sliding bars 623 are displaced by arranging the oil channels 628 and filling hydraulic oil in the oil channels 628, the short sliding bars 623 and the long sliding bars 622 are supported by the trapezoid blocks 626, the force-unloading studs 627 are rotated, the force-unloading studs 627 move downwards, the trapezoid blocks 626 move downwards, and the short sliding bars 623 and the long sliding bars 622 perform the same displacement yielding, so that the supporting columns 625 perform the same displacement movement; the structure is used for improving the unloading force bearing part 6, the unloading force bearing part 6 is controlled by the unloading force stud 627, the unloading force distance between the bottom die strip 3 and the side die block 4 can be adjusted simultaneously by rotating the unloading force stud 627, and the simultaneous translation of the bottom die strip 3 and the side die block 4 is ensured, so that the bottom die strip 3 and the side die block 4 always support the bottom edge of the box girder in a full range, and the damage and the inaccurate distance adjustment caused by the concentrated supporting points in the upward bending process of the bottom edge of the box girder are avoided.

In a further scheme, as shown in fig. 5, a horizontal sliding rail 71 is further fixedly arranged on the outer side of the supporting bar 621, a moving vehicle 72 is slidably arranged on the sliding rail 71, a guide rail 73 perpendicular to the end face of the poured box girder is arranged on the moving vehicle 72, a processing vehicle 74 is slidably arranged on the guide rail 73, a polishing roller 75 is rotatably arranged on the processing vehicle 74, the axis of the polishing roller 75 is perpendicular to the end face of the poured box girder, and the upper side of the polishing roller 75 is tangent to the bottom side face of the poured box girder.

Through setting up the grinding roller 75, grind the tiny upward deflection deformation of case roof beam, after the concrete solidifies, when carrying out the template dismantlement, die block 3 and side module 4 thoroughly demolish, the grinding roller 75 moves to the case roof beam bottom along with processing car 74 this moment, processing car 74 moves along with moving car 72 along slide rail 71, grind case roof beam tip bottom surface and the bulge that gives way nearby through grinding roller 75, make case roof beam tip bottom surface keep whole level once more, this structure is favorable to guaranteeing the level of the whole bottom surface of case roof beam, provide the horizontal bottom surface for follow-up construction and the installation of case roof beam, avoid the case roof beam when the plane is put because the supporting atress that the downward bulge of case roof beam tip led to is uneven.

Finally, it is noted that the above-mentioned preferred embodiments are only intended to illustrate rather than limit the invention, and that, although the invention has been described in detail by means of the above-mentioned preferred embodiments, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention as defined by the appended claims.

Claims (7)

1. A prefabricated big box girder's tip can be partly the steel template that falls which characterized in that: including supporting outer template (1) in case roof beam bottom surface outside, outer template (1) inwards has seted up along the bottom limit along the bridge direction cut-off groove (2), cut-off groove (2) position is equipped with the die block strip (3) of vertical unloading downwards and to both sides unload side module (4) of power, after concrete placement accomplishes, prestressing force steel beam stretch-draw before removing die block strip (3) and side module (4), accomplishes the power of unloading at roof beam both ends end arris position.

2. A prefabricated big box girder's tip can be partly the steel template that falls which characterized in that: the bottom die strip (3) and the side die block (4) are respectively provided with a plurality of limit baffles (5) close to the outer side of the edge of the outer die plate (1), so that the inner sides of the bottom die strip (3) and the side die block (4) are flush with the inner side of the outer die plate (1).

3. The prefabricated long girder end partially-detachable steel pallet according to claim 2, wherein: the outer side of the bottom die strip (3) is fixedly provided with a plurality of bottom die back ridges (31), the outer side of the side die block (4) is fixedly provided with a plurality of side die cushion blocks (41), the position of the truncated groove (2) of the outer layer die plate (1) is provided with a force unloading bearing part (6), and the force unloading bearing part (6) is respectively propped against the positions of the bottom die back ridges (31) and the side die cushion blocks (41).

4. A prefabricated long girder end partially-detachable steel pallet according to claim 3, wherein: the unloading bearing part (6) comprises two bearing plates (611) which are arranged in parallel, one end of each bearing plate (611) is fixed on the outer side of the outer layer template (1), the other end of each bearing plate is suspended outside the truncated groove (2), a plurality of fastening nuts (612) are fixedly arranged between the two bearing plates (611), fastening screws (613) are connected to the fastening nuts (612) in a threaded mode, and the fastening screws (613) are respectively propped against the side template cushion block (41) and the bottom die back edge (31).

5. A prefabricated long girder end partially-detachable steel pallet according to claim 3, wherein: the force unloading bearing part (6) comprises a supporting bar (621) which is distributed along the outsides of the bottom die bar (3) and the side modules (4), and two ends of the supporting bar (621) are fixed at two ends of the truncated groove (2) of the outer layer template (1) through connecting pieces; two long sliding rods (622) and two short sliding rods (623) are arranged in the supporting rods (621) in a sliding mode, the two long sliding rods (622) are located outside the bottom die strip (3), the two short sliding rods (623) are located outside the side die blocks (4), a plurality of inclined grooves (624) are formed in one sides of the long sliding rods (622) and the short sliding rods (623) which face the outer die plates (1), a plurality of supporting columns (625) are arranged on the side faces of the supporting rods (621) which face the outer die plates (1) in a vertical sliding mode, the bottom ends of the supporting columns (625) are supported on the inclined grooves (624), and the top ends of the supporting columns (625) are supported on the side die cushion blocks (41) and the bottom die back edges (31) respectively; two vertically slide between long slide bar (622) and be equipped with a trapezoidal piece (626), two long slide bar (622) support and be in trapezoidal piece (626) both sides oblique side, support bar (621) still threaded connection has one to unload power double-screw bolt (627), it supports to unload power double-screw bolt (627) one end trapezoidal piece (626) bottom, the other end is followed support bar (621) outside stretches out, the intercommunication has oil duct (628) of buckling between long slide bar (622) and short slide bar (623), oil duct (628) intussuseption is filled with hydraulic oil.

6. The prefabricated long girder end partially-detachable steel pallet according to claim 5, wherein: and piston heads (629) are arranged at the ends of the long sliding rod (622) and the short sliding rod (623) respectively, wherein the two ends of the oil duct (628) are straight-section channels, and the piston heads (629) are slidably arranged in the straight-section channels.

7. The prefabricated long girder end partially-detachable steel pallet according to claim 6, wherein: the support bar (621) outside has still set firmly a horizontally slide rail (71), it is equipped with locomotive (72) to slide on slide rail (71), be equipped with guided way (73) of perpendicular to case roof beam terminal surface of pouring on locomotive (72), it is equipped with a processing car (74) to slide on guided way (73), it is equipped with grinding roller (75) to rotate on processing car (74), grinding roller (75) axis perpendicular to case roof beam terminal surface of pouring, the upside of grinding roller (75) is tangent in the case roof beam bottom side of pouring.