CN108331370B - A reversible staircase construction plank road - Google Patents

Abstract

The invention discloses a reversible stair construction trestle, which relates to the building construction technology and comprises a rotatable main beam, a fixed main beam, an upper vertical column I, an upper vertical column II, a lower vertical column I, a lower vertical column II, a step bearing frame, a stair pedal and an anti-overturning supporting device, wherein the upper end and the lower end of the rotatable main beam are respectively connected with the upper vertical column I and the lower vertical column I, the inner sides of the upper vertical column I and the lower vertical column I are respectively fixedly connected with a bearing I connected with the upper end and the lower end of the rotatable main beam, the upper end and the lower end of the fixed main beam are respectively fixedly connected with the upper vertical column II and the lower vertical column II, the step bearing frame is fixedly connected between the rotatable main beam and the fixed main beam, the stair pedal is positioned on the step bearing frame, the anti-overturning supporting device comprises a main connecting shaft connected with the middle part of the fixed main beam and a supporting device connected with the outer end of the main connecting shaft and capable of rotating and swinging relative to the main connecting shaft, and the rotatable main beam can drive the fixed main beam, the step bearing frame, the stair pedal and the anti-overturning supporting device to rotate together between the upper vertical column I and the lower vertical column I.

Description

A reversible staircase construction plank road

Technical field

The invention relates to building construction technology, and in particular to a stair construction plank used in construction.

Background technique

After completing the concrete construction of the nth floor of the project under construction, when entering the n+1th floor construction, the methods for construction workers to go up and down the floor include: using simple wooden ladders, or climbing the formwork steel pipe support frame, but the more common The method is to use the building design stair template as the main passage for people to go up and down, and for the transportation of light materials and tools.

Existing practices have the following shortcomings:

1. Safety is not guaranteed: Before installing the steel bars of the stair ladder, anti-slip strips are usually nailed at intervals on the ladder board as upper and lower support points. However, due to many reasons such as the smooth surface of the ladder board, steep slope, and the need to carry light materials and tools, etc. , people falling down happen from time to time;

2. The quality of the ladder plate's formed steel bars is affected: After the stair riser board is installed, the workers use the formed ladder plate steel mesh as anti-slip facilities and step up and down. The lashing points, protective layer thickness, spacing, etc. of the steel bars are seriously damaged. ;

3. The finished product of the riser formwork installation is damaged: after the riser formwork is installed, workers step on the riser formwork up and down, which can easily cause displacement and falling off. During the concrete pouring and plastering process of the stairs, workers step on the riser formwork to complete the work. Processes such as pouring, vibrating, and plastering lead to displacement of the formwork, which is also one of the reasons why the stair treads have cross-sectional size deviations after the formwork is removed and the surface appearance of the ladder components is poor.

Contents of the invention

The object of the present invention is to provide a reversible stair construction plank in view of the above-mentioned shortcomings of the prior art, which is convenient and safe, can ensure the quality of semi-finished products such as formwork, steel bars, and concrete, and does not cause damage to the formwork installation, steel bars, etc. The construction of adjacent processes such as banding and concrete pouring forms mutual constraints and constraints.

The technical solution adopted by the present invention to achieve the above object is: a reversible stair construction plank road, which includes a rotatable main beam, a fixed main beam, an upper column I, an upper column II, a lower column I, a lower column II, and a step bearing. Force frame, stair tread, anti-overturning support device, the upper end of the rotatable main beam is connected to the upper column I, the lower end of the rotatable main beam is connected to the lower column I, the inner sides of the upper column I and lower column I are respectively fixedly connected to the rotatable main beam The bearing I connected at the upper and lower ends, the upper end of the fixed main beam is fixedly connected to the upper column II, the lower end of the fixed main beam is fixedly connected to the lower column II, and the step bearing frame is fixedly connected between the rotatable main beam and the fixed main beam. The stair treads are positioned on the step load-bearing frame. The anti-overturning support device includes a main connecting shaft fixedly connected to the middle position of the outer wall of the fixed main beam and a support device connected to the outer end of the main connecting shaft that can rotate and swing relative to the main connecting shaft. , the rotatable main beam can drive the fixed main beam, step load-bearing frame, stair treads, and anti-overturning support device to rotate between the upper column I and the lower column I.

A further technical solution of the present invention is: the rotatable main beam includes an upper rotatable main beam and a lower rotatable main beam, and a rotatable connector is connected between the upper rotatable main beam and the lower rotatable main beam; The fixed main beam includes an upper fixed main beam and a lower fixed main beam. A bracket connector is connected between the upper fixed main beam and the lower fixed main beam. The lower outer wall of the rotatable connector and the bracket connector are The lower outer walls are respectively connected to center columns extending downward, and a center column connecting rod is connected between the two center columns.

A further technical solution of the present invention is: the rotatable connector includes a casing I, a casing II, and an open-thread steel pipe. Both ends of the open-thread steel pipe are respectively provided with external threads, and the inner sides of the first ends of the casing I and casing II are The pipe wall is respectively provided with a section of internal thread that matches the external thread of the open-threaded steel pipe. The inner pipe walls of the second ends of casing I and casing II are respectively fixedly connected with bearings II. The first ends of casing I and casing II are respectively fixedly connected. The ends are connected to the external threads at both ends of the open-thread steel pipe through internal threads. The upper end of the upper rotatable main beam is connected to the bearing I on the inside of the upper column I. The lower end of the upper rotatable main beam is connected to the bearing II on the inside of the second end of the casing I. connection, the lower end of the lower rotatable main beam is connected to the bearing I on the inside of the lower column I, the upper end of the lower rotatable main beam is connected to the bearing II on the inside of the second end of the casing II, and the middle column is connected to the lower outer wall of the casing II. .

A further technical solution of the present invention is: the bracket connector includes a latch and a tubular bracket. The inner diameter of the bracket is slightly larger than the outer diameter of the upper fixed main beam and the lower fixed main beam. There are latch holes corresponding to each other. The upper end of the fixed main beam in the upper section is fixedly connected to the upper column II. The lower end of the fixed main beam in the upper section is inserted into the bracket through the upper port of the bracket and positioned with the bracket through the latch. The lower section is fixed. The lower end of the main beam is fixedly connected to the lower column II. The upper end of the lower fixed main beam is inserted into the bracket through the lower port of the bracket and positioned with the bracket through the latch. The middle column is connected to the lower outer wall of the bracket.

A further technical solution of the present invention is: the neutral column includes a support steel pipe, a hydraulic support rod, a ground claw connecting screw and a ground claw. The upper end of the support steel pipe is connected to the outer wall of the rotatable connector or the outer wall of the bracket connector, and the upper end of the hydraulic support rod is connected to the outer wall of the rotatable connector or the outer wall of the bracket connector. The lower end of the support steel pipe is connected. The lower end of the hydraulic support rod is connected to the upper end of the ground claw connecting screw. The middle part of the ground claw is provided with a through hole that matches the ground claw connecting screw. The ground claw is sleeved on the ground claw connecting screw. The lower end of the ground claw connecting screw is connected with Position the ground claw on the fixing nut on the ground claw connecting screw.

A further technical solution of the present invention is: the overall outer contour of the ground claw is in the shape of a truncated cone with a small top and a large bottom, a through hole is provided at the upper end of the ground claw, and the lower end of the ground claw is provided with evenly arranged protruding teeth, and the ground claw can rotate. It is placed on the ground claw connecting screw, and the ground claw can be tilted within the range of 0 to 60 degrees relative to the axis of the ground claw connecting screw.

A further technical solution of the present invention is: the support device includes a connecting steel sheet, a connecting pin, and a support rod. The connecting steel sheet is in the shape of "[", and the vertical arm of the connecting steel sheet is connected to the main connecting shaft and can be connected relative to the main connecting shaft. The shaft rotates, the connecting pin is connected between the two horizontal arms connecting the steel sheets, and one end of the support rod is rotatably connected to the connecting pin between the two horizontal arms connecting the steel sheets.

A further technical solution of the present invention is that the step load-bearing frame includes two vertical load-bearing arms and two horizontal load-bearing arms, and one end of the two horizontal load-bearing arms on the same side is connected with the two vertical load-bearing arms respectively. The bottom ends of the arms are connected vertically. The ends of the two horizontal load-bearing arms away from the two vertical load-bearing arms are connected with an intermediate load-bearing arm. The upper ends of the two vertical load-bearing arms, the horizontal load-bearing arms and the middle load-bearing arm are connected. The joints of the arms are fixedly connected to the inner wall of the rotatable main beam and the inner wall of the fixed main beam respectively. The stair treads are positioned in the space surrounded by two horizontal load-bearing arms and a middle load-bearing arm.

A further technical solution of the present invention is that the stair treads are fiberglass gratings.

A further technical solution of the present invention is: the upper column I includes an upper vertical section column I and an upper column connecting arm I inclinedly connected to the upper end of the upper vertical section column I and extending downward, and the lower column I includes a lower vertical section The upright column I and the lower column connecting arm I that is inclined and connected to the upper end of the lower vertical section column I and extends upward. The bearing I is respectively provided in the upper column connecting arm I and the lower column connecting arm I. The upper end of the rotatable main beam is connected to the upper column. The bearing I in the arm I is connected, and the lower end of the rotatable main beam is connected to the bearing I in the lower column connecting arm I; the upper column II includes the upper vertical section column II and is connected obliquely to the upper end of the upper vertical section column II and downwards The extended upper column connecting arm II, the lower column II includes the lower vertical section column II and the lower column connecting arm II that is inclined and connected to the upper end of the lower vertical section column II and extends upward. The upper end of the fixed main beam and the upper column connecting arm II connection, the lower end of the fixed main beam is connected to the lower column connecting arm II.

The reversible stair construction plank of the present invention has the following beneficial effects:

1. The reversible stair construction plank of the present invention not only solves the problem of people walking up and down the ladder, but also ensures their personal safety; the stair construction plank has its own supporting device and does not need to be placed on the formwork or steel bars, which can effectively ensure The quality of semi-finished products such as formwork, steel bars, and concrete facilitates construction;

2. The reversible stair construction plank of the present invention can achieve independent flipping of the upper and lower sections of the plank and overall flipping of the plank through the connecting bearing I of the rotatable main beam. The flip angle is 0° to 180°, while ensuring the passage of people. , as much as possible to reduce the interference with slab laying, formwork installation, concrete pouring and other processes; the overall length of the plank road can be adjusted according to the length of the steps on the design drawings, the lower section is a fixed length, the upper section is an adjustable length, and the main rotatable The position of the beam and the fixed main beam can be interchanged based on the site conditions. There is a hydraulic support rod in the middle column to support, control and adjust the height of the plank road frame to a certain extent. The ground claws use the vertical column as a vertical line, along the length of the ladder board. Adjustable from 0° to 60°, it can adapt well to ladders with different slopes. Anti-overturning support devices are installed in the middle of the fixed main beams in the upper and lower sections to effectively support the overturned and erected planks (angle <90°). The invention has reasonable design, stable structure, easy disassembly and assembly, and can be flexibly arranged according to site conditions;

3. The reversible staircase construction plank road of the present invention is easy to use and can be made of various materials such as steel and aluminum alloy. It can be made on-site or mass-produced in a factory.

The reversible stair construction plank road of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

Description of drawings

Figure 1 is a structural schematic diagram of the rotatable main beam of the reversible stair construction plank road of the present invention connected to the upper column I, the lower column I and the middle column;

Figure 2 is a schematic structural diagram of the connection between the fixed main beam of the reversible stairway construction plank of the present invention and the upper column II, the lower column II and the middle column;

Figure 3 is a schematic diagram of the connection between the rotatable connector and the upper rotatable main beam and the lower rotatable main beam;

Figure 4 is a schematic diagram of partially sectioned casing I and casing II based on Figure 3;

Figure 5 is a schematic structural diagram of the bracket connector;

Figure 6 is a structural schematic diagram of the connection between the bracket connector shown in Figure 5 and the upper fixed main beam and the lower fixed main beam;

Figure 7 is a schematic structural diagram of the connection between the central column, the rotating connector and the bracket connector;

Figure 8 is a partially exploded view of the center column;

Figure 9 is a schematic diagram of the combined structure of the center column;

Figure 10 is a schematic structural diagram of the center column's ground claw after rotation;

Figure 11 is a schematic structural diagram of the hydraulic support rod of the center column after it is retracted;

Figure 12 is a schematic structural diagram of the anti-overturning support device;

Figure 13 is a schematic structural diagram of the step bearing frame;

Figure 14 is a schematic structural diagram of the connection between the step load-bearing frame and the rotatable main beam or fixed main beam;

Figure 15 is a schematic structural diagram of the fiberglass grating;

Figure 16 is a schematic structural diagram of the connection between the upper rotatable main beam and the upper column I;

Figure 17 is a schematic diagram of the upper column I after partial sectioning based on Figure 16;

Figure 18 is a schematic structural diagram of the connection between the lower rotatable main beam and the lower column I;

Figure 19 is a schematic diagram of the lower column I partially cut away based on Figure 18;

Figure 20 is a structural schematic diagram of the connection between the upper fixed main beam and the upper column II;

Figure 21 is a schematic diagram of the upper column II partially cut away based on Figure 20;

Figure 22 is a structural schematic diagram of the connection between the lower fixed main beam and the lower column II;

Figure 23 is a schematic diagram of the lower column II partially cut away based on Figure 22;

Figure 24 is a schematic structural diagram of the rotatable main beam, fixed main beam, step bearing frame and other frame structures after they are connected;

Figure 25 is a schematic structural diagram of the reversible stair construction plank road of the present invention;

Figure 26 is a schematic structural diagram of the reversible stair construction plank of the present invention after it is flipped 60 degrees (in order to compare the structure before and after the flip, only the upper section of the stair construction plank is shown in the flipped state);

Figure 27 is a schematic structural diagram of the reversible stair construction plank of the present invention after it is flipped 90 degrees (in order to compare the structure before and after the flip, only the upper section of the stair construction plank is shown in the flipped state);

Explanation of reference numbers: 1-lower column I, 2-lower rotatable main beam, 3-rotatable connector, 4-upper rotatable main beam, 5-upper column I, 6-middle column, 7-lower column II ,8-Lower fixed main beam,9-Bracket connector,10-Upper fixed main beam,11-Upper column II,12-Anti-overturning support device,13-Casing II,14-Open tooth steel pipe,15 - Bushing I, 16 - Bearing II, 17 - Bracket, 18 - Latch hole, 19 - Latch, 20 - Middle column connecting rod, 21 - Support steel pipe, 22 - Hydraulic support rod, 23 - Ground claw connecting screw, 24 -Ground claw, 25-fixing nut, 26-main connecting shaft, 27-connecting steel plate, 28-connecting pin, 29-support rod, 30-vertical load-bearing arm, 31-horizontal load-bearing arm, 32-middle Bearing arm, 33-step bearing frame, 34-stair tread, 35-support device, 36-upper vertical column I, 37-upper column connecting arm I, 38-bearing I, 39-lower vertical column Ⅰ, 40-lower column connecting arm Ⅰ, 41-upper column connecting arm Ⅱ, 42-upper vertical section column Ⅱ, 43-lower vertical section column Ⅱ, 44-lower column connecting arm Ⅱ.

Detailed ways

As shown in Figures 1 to 25, the reversible stairway construction plank road of the present invention (referred to as "plank road") includes a rotatable main beam, a fixed main beam, an upper column I, an upper column II, a lower column I, and a lower column II. , step load-bearing frame, stair treads, anti-overturning support device.

As shown in Figure 1, the upper end of the rotatable main beam is connected to the upper column I, the lower end of the rotatable main beam is connected to the lower column I, and the insides of the upper column I and the lower column I are respectively fixedly connected with bearings connected to the upper and lower ends of the rotatable main beam. Ⅰ. In this embodiment, the rotatable main beam includes an upper rotatable main beam and a lower rotatable main beam, and a rotatable connecting piece is connected between the upper rotatable main beam and the lower rotatable main beam. A downwardly extending center column is connected to the lower outer wall of the rotatable connecting piece.

As shown in Figures 3 and 4, in this embodiment, the rotatable connector includes a casing I, a casing II, and an open-threaded steel pipe. Both ends of the open-threaded steel pipe are respectively provided with external threads. The casings I and casings II The inner pipe walls of the first end are respectively provided with a section of internal threads that match the external threads of the open-threaded steel pipes. The inner pipe walls of the second ends of casing I and casing II are respectively fixedly connected with bearings II. One end opposite the other. The first ends of casing I and casing II are respectively connected to the external threads at both ends of the open-threaded steel pipe through internal threads. The upper end of the upper rotatable main beam is connected to the bearing I on the inside of the upper column I. The lower end of the upper rotatable main beam is connected to the bearing II on the inside of the second end of the casing I. The lower end of the lower rotatable main beam is connected to the bearing I on the inside of the lower column I. The bearing I is connected, the upper end of the lower rotatable main beam is connected with the bearing II inside the second end of the casing II, and the middle column is connected with the lower outer wall of the casing II.

As shown in Figures 16 to 19, in this embodiment, the upper column I includes an upper vertical section column I and an upper column connecting arm I that is obliquely connected to the upper end of the upper vertical section column I and extends downward. The lower column I includes The lower vertical section column I and the lower column connecting arm I inclinedly connected to the upper end of the lower vertical section column I and extending upward, the bearing I is respectively arranged in the upper column connecting arm I and the lower column connecting arm I, and the upper end of the main beam can be rotated It is connected with the bearing I in the upper column connecting arm I, and the lower end of the rotatable main beam is connected with the bearing I in the lower column connecting arm I. The upper vertical section column I, the upper column connecting arm I, the lower vertical section column I, and the lower column connecting arm I are all made of steel pipes, and the joints are connected by welding.

As shown in Figure 2, the upper end of the fixed main beam is fixedly connected to the upper column II, and the lower end of the fixed main beam is fixedly connected to the lower column II. The fixed main beam includes an upper fixed main beam and a lower fixed main beam, which are fixed in the upper section. A bracket connector is connected between the main beam and the lower fixed main beam, and a neutral column extending downward is connected to the lower outer wall of the bracket connector.

As shown in Figures 5 and 6, in this embodiment, the bracket connector includes a latch and a tubular bracket. The inner diameter of the bracket is slightly larger than the outer diameter of the upper fixed main beam and the lower fixed main beam. The upper and lower brackets The slot walls at each end are respectively provided with latch holes corresponding to each other. The lower end of the upper fixed main beam and the upper end of the lower fixed main beam are also provided with through holes corresponding to the positions of the latch holes on the bracket. The upper end of the upper fixed main beam is fixedly connected to the upper column II. The lower end of the upper fixed main beam is inserted into the bracket through the upper port of the bracket and positioned with the bracket through the latch. The lower end of the lower fixed main beam is fixed to the lower column II. connection, the upper end of the fixed main beam of the lower section is inserted into the bracket through the lower port of the bracket and positioned with the bracket through the latch, and the middle column is connected to the lower outer wall of the bracket.

As shown in Figures 20 to 23, in this embodiment, the upper column II includes an upper vertical section column II and an upper column connecting arm II that is obliquely connected to the upper end of the upper vertical section column II and extends downward. The lower column II includes The lower vertical section column II and the lower column connecting arm II that is inclined and connected to the upper end of the lower vertical section column II and extends upward. The upper end of the fixed main beam is connected to the upper column connecting arm II, and the lower end of the fixed main beam is connected to the lower column. Arm II connection. The upper vertical section column II, the upper column connecting arm II, the lower vertical section column II, and the lower column connecting arm II are all made of steel pipes, and the joints are connected by welding.

As shown in Figures 2 and 12, the anti-overturning support device includes a main connecting shaft fixedly connected to the middle position of the outer wall of the fixed main beam and a support device connected to the outer end of the main connecting shaft that can rotate and swing relative to the main connecting shaft. In this embodiment, the anti-overturning support device is connected to the outer wall of the middle part of the upper fixed main beam and the lower fixed main beam respectively, and the inner side of the main connecting shaft is welded to the outer wall of the middle part of the upper fixed main beam and the lower fixed main beam. fixed. The support device includes a connecting steel piece, a connecting pin, and a support rod. The connecting steel piece is in the shape of "[". The vertical arm of the connecting steel piece is connected to the main connecting shaft and can rotate relative to the main connecting shaft. The connecting pin is connected to the connecting rod. between two horizontal arms of the steel sheet, and one end of the support rod is rotatably connected to the connecting pin connecting the two horizontal arms of the steel sheet. The entire support device can be rotated within 360° around the main connection axis to adjust different support directions. The support rod can rotate around the connecting pin within the range of 0° to 270°, making it easy to adjust different support angles. When the plank road is lying flat, the upper column I, the upper column II, the lower column I, the lower column II and the middle column jointly support the plank road. The anti-overturning support device is stored at the edge of the upper fixed main beam and the lower fixed main beam, as shown in the figure. 25 shown. When the plank road is overturned (angle <90°), rotate and open the support rods of the anti-overturning support device that are usually close to the upper fixed main beam and the lower fixed main beam to effectively support the overturned plank road, as shown in Figure 26 shown.

As shown in Figures 7 to 11, the neutral column includes a support steel pipe, a hydraulic support rod, a ground claw connecting screw and a ground claw. The upper end of the support steel pipe is connected to the outer wall of the rotatable connector or the outer wall of the bracket connector. The support steel pipes of the two neutral columns The outer walls are connected with central column connecting rods. The hydraulic support rod is telescopic, and its lower end is a telescopic end. The hydraulic support rod can effectively adjust the most suitable height of the support. The upper end of the hydraulic support rod is connected to the lower end of the support steel pipe. The lower end of the hydraulic support rod is fixedly connected to the upper end of the ground claw connecting screw through welding. There is a through hole in the middle of the ground claw that matches the ground claw connecting screw. The ground claw is sleeved on the ground claw connecting screw. On the ground claw connecting screw, the lower end is connected with a fixing nut that positions the ground claw on the ground claw connecting screw. The overall outer contour of the ground claw is a truncated cone shape with a small top and a large bottom. The through hole is set at the upper end of the ground claw. The lower end of the ground claw is equipped with evenly arranged protruding teeth. The ground claw can be rotatably sleeved on the ground claw connecting screw. The axis of the relative ground claw connecting screw can be tilted within the range of 0° to 60°, and can be well adapted to ladders with different slopes. It can better allow the ground claw teeth to contact the ladder, making the neutral column grip the ground firmly and reliably.

As shown in Figures 13 and 14 and Figures 24 and 25, the step bearing frame is fixedly connected between the rotatable main beam and the fixed main beam, and the stair treads are positioned on the step bearing frame. As shown in Figure 18, the stair treads It is fiberglass grating. The step load-bearing frame includes two vertical load-bearing arms and two horizontal load-bearing arms. One end of the same side of the two horizontal load-bearing arms is vertically connected to the bottom end of the two vertical load-bearing arms. The two horizontal load-bearing arms The end of the load-bearing arm away from the two vertical load-bearing arms is connected to an intermediate load-bearing arm. The upper ends of the two vertical load-bearing arms, the connection between the horizontal load-bearing arm and the middle load-bearing arm are respectively connected with the rotatable main beam. The inner wall and the inner wall of the fixed main beam are fixedly connected, and the stair treads are positioned in the space surrounded by two horizontal load-bearing arms and a middle load-bearing arm. In this embodiment, the vertical load-bearing arm, the horizontal load-bearing arm and the middle load-bearing arm of the step load-bearing frame are all made of angle steel, and the connections between them are welded. The connection between the step bearing frame, the rotatable main beam and the fixed main beam is also welded.

As shown in Figures 26 and 27, the rotatable main beam of the plank road of the present invention can drive the fixed main beam, step load-bearing frame, stair treads, anti-overturning support device and other devices to rotate together with it between the upper column I and the lower column I. . After the plank road rotates, the neutral column connected to the bracket connector in the middle of the fixed main beam is suspended in the air and no longer touches the ground. At this time, the support rod of the anti-overturning support device is rotated so that the support rod supports the weight of one side of the fixed main beam.

The above embodiments are only preferred embodiments of the present invention. The structure of the present invention is not limited to the forms listed in the above embodiments. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present invention shall be included in within the protection scope of the present invention.

Claims (8)

1. The utility model provides a rotatable stair construction landing stage, a serial communication port, including rotatable girder, fixed girder, go up stand I (5), go up stand II (11), lower stand I (1), lower stand II (7), step load frame (33), stair tread (34), prevent toppling strutting arrangement (12), rotatable girder upper end is connected with last stand I (5), rotatable girder lower extreme is connected with lower stand I (1), the inboard fixedly connected with of last stand I (5) and lower stand I (1) respectively with rotatable girder upper and lower end bearing I (38), fixed girder upper end and last stand II (11) fixed connection, fixed girder lower extreme and lower stand II (7) fixed connection, step load frame (33) fixed connection is between rotatable girder and fixed girder, stair tread (34) are fixed on step load frame (33), prevent toppling strutting arrangement (12) include with the outer wall of fixed girder lean on middle part position fixed connection's main connecting axle (26) and connect at main connecting axle (26) outer end rotatable about main connecting axle (26) and rotatable supporting arrangement (35), rotatable girder (33), rotatable supporting arrangement (1) and rotatable girder between the fixed stand I and lower bearing I; the rotatable main beam comprises an upper rotatable main beam (4) and a lower rotatable main beam (2), and a rotatable connecting piece (3) is connected between the upper rotatable main beam (4) and the lower rotatable main beam (2); the fixed girder comprises an upper section fixed girder (10) and a lower section fixed girder (8), a bracket connecting piece (9) is connected between the upper section fixed girder (10) and the lower section fixed girder (8), the outer wall of the lower side of the rotatable connecting piece (3) and the outer wall of the lower side of the bracket connecting piece (9) are respectively connected with a downward extending middle vertical column (6), and a middle vertical column connecting rod (20) is connected between the two middle vertical columns (6); the stair tread (34) is a glass fiber reinforced plastic grid.

2. The reversible stair construction trestle according to claim 1, characterized in that the rotatable connecting piece (3) comprises a sleeve I (15), a sleeve II (13) and a tooth-opening steel pipe (14), external threads are respectively arranged at two ends of the tooth-opening steel pipe (14), the sleeve I (15) and the inner side pipe wall of the first end of the sleeve II (13) are respectively provided with an internal thread matched with the external threads of the tooth-opening steel pipe (14), the sleeve I (15) and the inner side pipe wall of the second end of the sleeve II (13) are respectively fixedly connected with a bearing II (16), the sleeve I (15) and the first end of the sleeve II (13) are respectively connected with the external threads of two ends of the tooth-opening steel pipe (14) through the internal threads, the upper end of the upper rotatable main beam (4) is connected with a bearing I (38) on the inner side of the upper upright post I (5), the lower end of the upper rotatable main beam (4) is connected with a bearing II (16) on the inner side of the second end of the sleeve I (15), the lower end of the lower rotatable main beam (2) is connected with a bearing I (38) on the inner side of the lower upright post I (1), and the upper end of the lower rotatable main beam (2) is connected with a bearing II (16) on the inner side of the upper upright post (13).

3. The reversible stair construction gallery according to claim 1, wherein the bracket connecting piece (9) comprises a bolt (19) and a tubular bracket (17), the inner diameter of the bracket (17) is slightly larger than the outer diameters of the upper section fixed main beam (10) and the lower section fixed main beam (8), bolt holes (18) with mutually corresponding positions are respectively arranged on the groove walls of the upper end and the lower end of the bracket (17), the upper end of the upper section fixed main beam (10) is fixedly connected with the upper upright post II (11), the lower end of the upper section fixed main beam (10) is inserted into the bracket (17) through an upper port of the bracket (17) and is mutually positioned with the bracket (17) through the bolt (19), the lower end of the lower section fixed main beam (8) is fixedly connected with the lower upright post II (7), the upper end of the lower section fixed main beam (8) is inserted into the bracket (17) through a lower port of the bracket (17) and is mutually positioned with the bracket (17) through the bolt (19), and the middle upright post (6) is connected with the outer wall of the lower side of the bracket (17).

4. The reversible stair construction trestle according to claim 1, characterized in that the center pillar (6) comprises a supporting steel pipe (21), a hydraulic supporting rod (22), a ground claw connecting screw (23) and a ground claw (24), the upper end of the supporting steel pipe (21) is connected with the outer wall of the rotatable connecting piece (3) or the outer wall of the bracket connecting piece (9), the upper end of the hydraulic supporting rod (22) is connected with the lower end of the supporting steel pipe (21), the lower end of the hydraulic supporting rod (22) is connected with the upper end of the ground claw connecting screw (23), a through hole matched with the ground claw connecting screw (23) is arranged in the middle of the ground claw (24), the ground claw (24) is sleeved on the ground claw connecting screw (23), and a fixing nut (25) for positioning the ground claw (24) on the ground claw connecting screw (23) is connected with the lower end of the ground claw connecting screw (23).

5. The reversible stair construction trestle according to claim 4, characterized in that the whole outline of the ground claw (24) is in a shape of a round table with a small upper part and a large lower part, the through hole is arranged at the upper end of the ground claw (24), the lower end of the ground claw (24) is provided with protruding teeth which are uniformly distributed, the ground claw (24) is rotatably sleeved on the ground claw connecting screw rod (23), and the ground claw (24) can incline within the range of 0-60 degrees relative to the axis of the ground claw connecting screw rod (23).

6. The reversible stair construction trestle according to claim 1, characterized in that the supporting means comprises a connecting steel sheet (27), a connecting pin shaft (28) and a supporting rod (29), the connecting steel sheet (27) is in a shape of a' [, a vertical arm of the connecting steel sheet (27) is connected with the main connecting shaft (26) and can rotate relative to the main connecting shaft (26), the connecting pin shaft (28) is connected between two horizontal arms of the connecting steel sheet (27), and one end of the supporting rod (29) is rotatably connected on the connecting pin shaft (28) between two horizontal arms of the connecting steel sheet (27).

7. The reversible stair construction trestle according to claim 1, characterized in that the step bearing frame (33) comprises two vertical bearing arms (30) and two horizontal bearing arms (31), one end of the same side of each of the two horizontal bearing arms (31) is respectively and vertically connected with the bottom ends of the two vertical bearing arms (30), an intermediate bearing arm (32) is connected between one ends of the two horizontal bearing arms (31) far away from the two vertical bearing arms (30), the upper ends of the two vertical bearing arms (30), the connection parts of the horizontal bearing arms (31) and the intermediate bearing arms (32) are respectively and fixedly connected with the inner side walls of the rotatable main beams and the inner side walls of the fixed main beams, and the stair treads (34) are positioned in the space enclosed by the two horizontal bearing arms (31) and the intermediate bearing arms (32).

8. The reversible stair construction trestle according to claim 1, characterized in that the upper upright i (5) comprises an upper upright section upright i (36) and an upper upright connecting arm i (37) obliquely connected to the upper end of the upper upright section upright i (36) and extending downward, the lower upright i (1) comprises a lower upright section upright i (39) and a lower upright connecting arm i (40) obliquely connected to the upper end of the lower upright section upright i (39) and extending upward, bearings i (38) are respectively provided in the upper upright connecting arm i (37) and the lower upright connecting arm i (40), the upper end of the rotatable main beam is connected with bearings i (38) in the upper upright connecting arm i (37), and the lower end of the rotatable main beam is connected with bearings i (38) in the lower upright connecting arm i (40); the upper upright post II (11) comprises an upper vertical section upright post II (42) and an upper upright post connecting arm II (41) which is obliquely connected to the upper end of the upper vertical section upright post II (42) and extends downwards, the lower upright post II (7) comprises a lower vertical section upright post II (43) and a lower upright post connecting arm II (44) which is obliquely connected to the upper end of the lower vertical section upright post II (43) and extends upwards, the upper end of the fixed girder is connected with the upper upright post connecting arm II (41), and the lower end of the fixed girder is connected with the lower upright post connecting arm II (44).