CN211306818U - Stretch-draw girder steel convenient to steel centre form is extracted - Google Patents

Abstract

The utility model provides a stretch-draw girder steel convenient to steel centre form is extracted, includes fixed steel crossbeam, fixed steel crossbeam top is equipped with the recess, the inside sliding frame that is equipped with of recess, fixed steel crossbeam both sides are equipped with the side reinforcing plate, the utility model discloses a reduce the fixed steel crossbeam top surface elevation of stretch-draw end to open the method of recess in the middle, both satisfied the high requirement of the whole stretch-draw of large-tonnage jack, can make whole steel centre form conveniently extract again.

Description

Stretch-draw girder steel convenient to steel centre form is extracted

Technical Field

The utility model relates to a stretch-draw field is extracted to hollow plate steel centre form, especially relates to a stretch-draw girder steel convenient to steel centre form is extracted.

Background

The pre-tensioning method pedestal for a special precast yard adopts a pier structure and consists of a reinforced concrete bearing pier, a table top and a fixed steel beam. The pretensioning method prestressed hollow slab prefabrication of the prefabricating field adopts the construction processes of forming an internal mold by an air bag and manually stretching a steel strand, which are all backward construction processes. In order to actively implement the relative requirements of advanced popularization and obsolete lagging of the state, industry and unit, the pre-tensioning method hollow slab prefabrication is changed into a construction process of integral steel internal mold and integral tensioning and releasing of steel strands.

When the air bag internal mold is adopted, 7 hollow plates with the length of 16m can be simultaneously prefabricated in each groove of the prefabrication field pedestal, the distance between the hollow plates is 1m, and the distance from the fixed steel cross beam at the stretching end is not more than 3 m. When the integral steel inner mold is adopted, if 7 hollow plates with the thickness of 16m are still prefabricated in each groove, the hollow plates can be pulled out with great difficulty. When the steel inner die is pulled out, the fixed steel cross beam crossing the tensioning end is needed. The fixed steel cross beam at the tensioning end is of a box body structure welded by steel plates of 25-30mm, the length is 2.5m, the width is 56cm, the height is 67cm, the thicknesses of vertical plates on the front side and the back side are 30mm, the thickness of a horizontal plate is 25mm, 6 layers are formed, the net height of each layer is 75-100mm, and 2 rows of notches penetrating through the steel strands are formed in the middle of each vertical plate. The difference between the elevation of the top surface of the vertical plate of the tension end fixed steel cross beam and the height of the top surface of the bottom plate of the hollow plate is about 32.5cm-6cm =26.5cm, and although the steel inner mold can be contracted and lowered by 5-9 cm when being separated from concrete, the steel inner mold cannot be successfully pulled out due to the reasons that the whole steel inner mold is long in length, large in rigidity, close to the steel cross beam at the tension end and the like.

When the hollow slab is integrally tensioned by the pretensioning method, a large-tonnage jack is usually adopted due to large tensioning force. When a large-tonnage jack is adopted for integral tensioning and releasing construction, the diameter of the jack is large (such as the diameter phi 390mm of a 300t jack and the diameter phi 450mm of a 400t jack), the height difference between the top surface of a vertical plate of a fixed steel cross beam at a tensioning end and the central line of the jack (the central line of finish rolling deformed steel bar) is not less than 195mm (taking the 300t jack as an example), otherwise, the extending part of the jack is suspended or is not in a straight line with the axial line of the finish rolling deformed steel bar, and great safety and quality hidden dangers exist. In addition, because the prestressed steel strand is changed into an integral tensioning and releasing construction process, the large-tonnage jack is stressed greatly at the jacking positions of the fixed cross beam and the movable steel cross beam and needs to be reinforced.

SUMMERY OF THE UTILITY MODEL

The utility model discloses a main aim at provides a stretch-draw girder steel convenient to steel centre form is extracted solves the problem that hollow plate steel centre form can not successfully extract.

In order to solve the technical problem, the utility model discloses the technical scheme who adopts is: a tension steel beam convenient for pulling out a steel inner die comprises a fixed steel cross beam, wherein a groove is formed above the fixed steel cross beam, a sliding frame is arranged in the groove, and side reinforcing plates are arranged on two sides of the fixed steel cross beam;

and the steel inner die drawing die in the hollow slab slides out of the sliding frame.

In the preferred scheme, one side of the fixed steel beam is provided with a notch.

In the preferred scheme, one side of the fixed steel beam is provided with a bearing plate, and the bearing plate is arranged on one side of a notch of the fixed steel beam.

In the preferred scheme, still be equipped with movable girder steel, be equipped with the jack between movable girder steel and the fixed steel crossbeam.

In the preferred scheme, the steel strand wires both ends and the screw-thread steel of stretch-draw usefulness are connected, and the screw-thread steel passes fixed steel beam's notch, bearing plate and activity girder steel, the screw-thread steel tip is equipped with stop nut, steel strand wires tip and stop nut fixed connection, the stopper supports and leans on at the activity girder steel terminal surface.

The utility model provides a stretch-draw girder steel convenient to steel centre form is extracted has solved the problem that whole steel centre form was extracted well through the mode of opening the recess to current steel crossbeam, has realized old and useless utilization, has gained very good economic benefits and social, also provides fine reference for the design of the hollow slab pedestal of similar pretension method in future reform transform and the whole stretch-draw of large-tonnage jack and put a fixed steel crossbeam. After calculation, the steel beam is grooved, the structural stress and deformation completely meet the standard requirements.

Drawings

The invention will be further explained with reference to the following figures and examples:

FIG. 1 is a schematic view of the overall construction of the present invention;

FIG. 2 is a schematic view of the overall construction of the present invention;

FIG. 3 is a view of the overall construction of the present invention;

FIG. 4 is a left side view of the overall construction structure of the present invention;

FIG. 5 is a front sectional view of the overall construction of the present invention;

FIG. 6 is a side view structure diagram of the overall construction of the present invention;

FIG. 7 is a structural view of the overall construction drawing die of the present invention sliding to the sliding frame;

FIG. 8 is a partial enlarged structural view of the fixed steel beam of the present invention;

FIG. 9 is a disassembled structure view of the fixed steel beam of the present invention;

in the figure: a hollow slab 1; a concrete bearing pier 2; fixing the steel beam 3; a notch 301; deformed steel bars 4; a steel strand 401; a table top 5; a pressure bearing plate 6; a jack 7; a movable steel beam 8; a steel inner mold 9; a slide frame 10; a limit nut 11; a jack reinforcing plate 12; and a side reinforcing plate 13.

Detailed Description

Example 1

As shown in fig. 1-9, a stretch-draw girder steel convenient to steel centre form is extracted, including fixed steel crossbeam 3, fixed steel crossbeam 3 top is equipped with the recess, the inside sliding frame 10 that is equipped with of recess, fixed steel crossbeam 3 both sides are equipped with side reinforcing plate 13, the 9 drawing dies of steel centre form in 1 inside of hollow core slab roll-off from sliding frame 10 roll-off. By the structure, the problem of extracting the whole steel inner die is well solved by the mode of forming the groove on the existing steel beam, and the sliding frame 10 causes less friction when the steel inner die 9 is pulled out, so that the structure is simple and the use is convenient.

A certain height distance is reserved between the steel inner die 9 and the sliding frame 10 in the hollow slab 1, the height between the bottom surface of the sliding frame 10 and the bottom surface of the steel inner die 9 is 11-12cm, and the steel inner die 9 is pulled out from the sliding frame 10. The drawing die of the steel inner die 9 can conveniently slide out from the sliding frame 10.

In the preferred scheme, one side of the fixed steel beam 3 is provided with a bearing plate 6, and the bearing plate 6 is arranged on one side of a notch 301 of the fixed steel beam 3. The bearing plate 6 is used for strengthening the effect of fixing the steel beam 3, and when the deformed steel bar 4 passes through the bearing plate 6 in tensioning, the deformed steel bar needs to be connected by the limit nut 11 and supported by the bearing plate 6 to perform tensioning stabilization.

And side reinforcing plates 13 are arranged on two sides of the fixed steel cross beam 3. For reinforcing the integral strong steel cross beam 3.

In a preferred scheme, one side of the fixed steel beam is provided with a notch 301. The notch 301 is mainly used for threading the deformed steel bar 4.

In the preferred scheme, still be equipped with movable girder steel 8, be equipped with jack 7 between movable girder steel 8 and the fixed steel crossbeam 3. Two jacks 7 jack up the movable steel beam 8, and the movable steel beam 8 is used for tensioning.

In the preferred scheme, steel strand 40101 both ends and the screw-thread steel 4 of stretch-draw usefulness are connected, and screw-thread steel 4 passes notch 301, bearing plate 6 and the activity girder steel 8 of fixed steel crossbeam 3, 4 tip of screw-thread steel are equipped with stop nut 11, steel strand 401 tip and stop nut 11 fixed connection, stop nut 11 supports and leans on at activity girder steel 8 terminal surfaces. From this structure, stop nut 11 is used for spacing to screw-thread steel 4, realizes the stretch-draw to hollow plate 1 bottom.

Example 2

Further described with reference to embodiment 1, as shown in fig. 1 to 9, the construction method for installing and fixing the steel beam 3 is as follows:

the geometric dimension and the top surface elevation of the original tension end fixed steel cross beam 3, the platform surface elevation of the pedestal 5 and the position of the axis line of the prestress steel strand 40101 are rechecked by a measurer, and the descending height h of the fixed steel cross beam is calculated by taking the height difference between the top surface of the vertical plate of the fixed steel cross beam and the height difference between the top surface of the prestress steel strand 40101 and 20-22cm as a standard.

And adjusting the elevation and the position of the fixed steel beam 3 at the tensioning end according to the calculated descending height h, ensuring that the position of the descended fixed steel beam 3 is centered when the descended fixed steel beam passes through finish rolling deformed steel bars, welding the descended fixed steel beam with a steel plate on the concrete force bearing pier 2, and stably supporting the bottom of the fixed steel beam 3 by profile steel according to the height from the ground.

And 3 rows of fixed steel cross beams at the tensioning ends are grooved, the width of the grooves is 90cm, and the depth is determined according to specific conditions (the difference between the top surface elevation of the grooves and the center line elevation of the prestressed steel strand (finish-rolled deformed steel) is controlled by 11-12 cm). Taking the axis of the table top as a reference, symmetrically drawing the positions of the grooves on the surfaces of the front vertical plate, the rear vertical plate and the horizontal plate, cutting the horizontal plate and the vertical plate within the range of 90cm from the welding line by using a plasma cutting machine, and then cutting the horizontal plate within the range of 90 cm; then, the front and rear vertical plates within 90cm are respectively cut.

Further, processing the cut front and rear vertical plates into a left vertical plate and a right vertical plate which have the same depth as the groove and the same width as the steel cross beam, and firmly welding the left vertical plate and the right vertical plate with the front and rear vertical plates of the second layer of horizontal plate to form a sliding frame 10; furthermore, the cut horizontal plate 1 is firmly welded with the left vertical plate, the right vertical plate, the front vertical plate and the rear vertical plate. The welding lines are all welded by single-side angle welding, and the height is 8 mm.

Further, taking the center line of the table top as a reference, symmetrically marking the middle point of the extending position of the jack, and additionally welding a 3cm steel plate which is 3-5cm larger than the diameter of the jack;

furthermore, a steel plate with the thickness of 2cm is additionally welded in the operation range of the jacks at the two ends of the fixed steel beam. Thus a grooved fixed steel cross-beam 3 is formed.

The above-mentioned embodiments are merely preferred embodiments of the present invention, and should not be considered as limitations of the present invention, and the protection scope of the present invention should be defined by the technical solutions described in the claims, and includes equivalent alternatives of technical features in the technical solutions described in the claims. Namely, equivalent alterations and modifications within the scope of the invention are also within the scope of the invention.

Claims (5)

1. The utility model provides a stretch-draw girder steel convenient to steel centre form is extracted which characterized by: the steel beam fixing device comprises a fixed steel beam (3), wherein a groove is formed above the fixed steel beam (3), a sliding frame (10) is arranged in the groove, and side reinforcing plates (13) are arranged on two sides of the fixed steel beam (3);

the steel inner die (9) in the hollow plate (1) slides out from the sliding frame (10).

2. A tensioned steel beam facilitating the extraction of an inner steel form as claimed in claim 1 wherein: one side of the fixed steel beam (3) is provided with a notch (301).

3. A tensioned steel beam facilitating the extraction of an inner steel form as claimed in claim 2 wherein: one side of the fixed steel beam (3) is provided with a bearing plate (6), and the bearing plate (6) is arranged on one side of a notch (301) of the fixed steel beam (3).

4. A tensioned steel beam facilitating the extraction of an inner steel form as claimed in claim 1 wherein: and a movable steel beam (8) is further arranged, and a jack (7) is arranged between the movable steel beam (8) and the fixed steel beam (3).

5. A tensioned steel beam facilitating the extraction of an inner steel die as claimed in claim 4 wherein: steel strand wires (401) both ends that the stretch-draw was used are connected with screw-thread steel (4), and screw-thread steel (4) pass notch (301), bearing plate (6) and the activity girder steel (8) of fixed steel crossbeam (3), screw-thread steel (4) tip is equipped with stop nut (11), steel strand wires (401) tip and stop nut (11) fixed connection, stop nut (11) are supported and are leaned on at activity girder steel (8) terminal surface.

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