Prefabricated step plate unit, production method and mounting structure

Abstract

The invention relates to a prefabricated step plate unit, a production method and a mounting structure, the step plate unit comprises a concrete step, a pre-embedded steel rib, a screw and an adjusting nut, the concrete step is of a flat plate structure, one end of the pre-embedded steel rib is welded with a tensile supporting foot and embedded into the concrete step, the exposed end of the pre-embedded steel rib is provided with a hole, the screw penetrates into the hole, and the adjusting nut is connected with the screw. Adjusting nuts are respectively sleeved on the screw on two sides of the pre-embedded steel rib, and a fixing hole is arranged on the end face of the screw. When the step plate unit is installed, fixing mechanisms are arranged at the two ends of the bottom of the concrete step respectively, each fixing mechanism comprises a step beam bearing steel plate, a conversion base located at the top of the step beam bearing steel plate and a screw sleeve located at the top of the conversion base, and a perforated baffle is vertically arranged at the front end of the concrete step and fixed to a screw through a screw. And the screws at the two ends of the concrete step are supported and limited by the screw sleeves in the fixing mechanisms at the two ends respectively. The invention has the advantages of light weight, low cost, low requirement on mounting precision and easiness in production.

Description

Technical Field

[0001] The invention relates to the technical field of assembled stairs, and in particular to a prefabricated tread plate unit, a production method and an installation structure. Background Art

[0002] In the field of prefabricated buildings, the use of prefabricated stairs helps to increase the construction speed. The prefabricated stair treads in the prior art usually use L-shaped prefabricated concrete treads, with bolts pre-embedded at the bottom of the stair treads, and the stair treads are installed by connecting the pre-embedded bolts with the steel plates extending from the side of the ladder beam. This stair installation structure requires high installation accuracy, and the installation accuracy is completely guaranteed by the accuracy of the pre-embedded bolts and the welding accuracy. Without excessive installation adjustments, production and installation deviations cannot be absorbed. Moreover, the prefabricated concrete treads require bidirectional reinforcement, so that the minimum thickness of the stair treads cannot be less than 80mm, and the weight of a single stair tread exceeds 100kg. This structural design is difficult to operate by manpower without installation machinery. Even if UHPC (ultra-high performance concrete) materials are used instead of ordinary concrete to reduce the thickness of the tread structure, the cost is artificially high and it is not suitable for mass production applications. Summary of the invention

[0003] The present invention firstly discloses a prefabricated tread plate unit, which adopts a thinner flat plate as a stair tread, and combines it with embedded steel ribs to form a stress state to jointly bear the load, which can not only reduce the production difficulty of the tread, but also reduce the weight of the tread.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is: A prefabricated tread unit comprises a concrete tread, embedded steel ribs, a full-thread screw and an adjusting nut. The concrete tread is a flat plate structure and is cast with C60 or higher high-strength concrete. The embedded steel ribs are cut from steel plates, and a tensile support foot is welded perpendicularly to the steel plate at one end of the steel plate. The tensile support foot end of the embedded steel rib is embedded in the concrete tread, and holes are respectively opened at at least two ends of the exposed end of the embedded steel rib. Two embedded steel ribs are symmetrically arranged along the width direction of the concrete tread, and the full-thread screw is inserted into the corresponding hole between the two embedded steel ribs. Adjusting nuts are respectively sleeved on both sides of the embedded steel rib on the full-thread screw, and fixing holes are opened on the two end faces of the full-thread screw.

[0005] Furthermore, the top surface of the concrete step is provided with an anti-slip groove.

[0006] Furthermore, a perforated baffle is provided on one side of the lower part of the concrete step, the perforated baffle is vertically arranged with the concrete step, and the perforated baffle is fixed to the fixing hole of the full bolt screw by screws.

[0007] The present invention also discloses a production method of the prefabricated tread plate unit, which includes the following contents: Step 1) Place the steel bottom mold on the steel mold table; Step 2) Place a pair of L-shaped positioning molds on the steel mold platform on both sides of the steel bottom mold, so that the two positioning molds are clamped and fit with the steel bottom mold; Step 3) Connect the two embedded steel ribs through a full-thread screw to form a plane truss, and set adjustment nuts on both sides of each embedded steel rib on the full-thread screw; Step 4) Invert the plane truss above the inner cavity of the steel bottom mold, install the two ends of the full-thread screw on the two end positioning molds with positioning bolts, so that the tensile support legs of the embedded steel ribs are suspended in the inner cavity of the steel bottom mold, set the positioning nuts on the positioning bolts, adjust the position of the plane truss, and lock the position with the positioning nuts; Step 5) Pour concrete into the inner cavity of the steel bottom mold and vibrate it to make it smooth. After curing, demould it and separate the positioning bolts from the full-thread screw.

[0008] Furthermore, a plurality of spaced protrusions are formed on the bottom surface of the inner cavity of the steel bottom mold.

[0009] The present invention further discloses an installation structure of the above-mentioned prefabricated tread unit, comprising the above-mentioned prefabricated tread unit, fixing mechanisms located at the two ends of the bottom of the prefabricated tread unit, and a perforated baffle located on one side of the lower part of the prefabricated tread unit; the fixing mechanism comprises an L-shaped ladder beam supporting steel plate, a conversion base and a screw sleeve with an open top, the vertical plate of the ladder beam supporting steel plate is fixed to the ladder beam, the conversion base is fixedly connected to the horizontal plate of the ladder beam supporting steel plate, the relative position of the conversion base and the horizontal plate of the ladder beam supporting steel plate is adjustable, a limit plate is arranged at intervals on the top of the conversion base, the limit plate is perpendicular to the conversion base, a screw sleeve is clamped between the limit plates, the full-threaded screws located at the two ends of the prefabricated tread unit are supported and limited by the screw sleeve, the perforated baffle is arranged perpendicular to the concrete step, and the perforated baffle is fixed to the fixing hole of the full-threaded screw by screws.

[0010] Furthermore, fixing holes are respectively provided at both ends of the horizontal plate of the ladder beam supporting steel plate, and a strip hole is provided between the fixing holes at both ends; strip holes are respectively provided at both ends of the conversion base, and a fixing hole is provided between the strip holes at both ends; the conversion base and the horizontal plate of the ladder beam supporting steel plate are fixedly connected by fixing bolts, and the adjusting bolts are successively passed through the strip holes on the horizontal plate of the ladder beam supporting steel plate and the fixing holes on the conversion base to support the bottom of the screw sleeve.

[0011] Furthermore, the contact surface between the screw sleeve and the full-thread screw is an arc-shaped surface.

[0012] Furthermore, the perforated baffle is an aluminum plate.

[0013] Furthermore, the horizontal plate and the vertical plate of the ladder beam supporting steel plate are connected by a stiffening plate.

[0014] The concrete tread in the prefabricated tread plate unit designed by the present invention is a flat plate, which is easier to process than the L-shaped plate in the prior art, and helps to reduce the difficulty of production; the concrete tread is a thin plate cast by high-strength concrete of about C60, which has low cost and small thickness. The weight of a single tread can be reduced by more than 50% compared with the structure in the prior art. The present invention uses the designed concrete tread and the embedded steel rib to form a combined stress state to jointly bear the load. The installation method of the prefabricated tread plate unit provided by the present invention realizes the adjustment of the three-way position, can absorb the installation error to the greatest extent, and can reduce the high requirements for installation accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a schematic diagram of the side structure of the prefabricated tread plate unit in the embodiment; Figure 2 This is a front structural schematic diagram of a prefabricated tread plate unit in an embodiment; Figure 3 This is a schematic diagram of the side installation structure of the prefabricated tread plate unit in the embodiment; Figure 4 This is a schematic diagram of the front installation structure of the prefabricated tread plate unit in the embodiment; Figure 5 for Figure 4 A partial enlarged view of the Figure 6 for Figure 4 A top view of Figure 7 This is a schematic diagram of the installation of the stair step assembly in the embodiment; Figure 8 Schematic diagram of the production process structure of the prefabricated tread unit.

[0016] Description of Figure Numbers: 1. Concrete tread; 2. Embedded steel ribs; 3. Fully threaded screws; 4. Adjustment nuts; 5. Fixing holes; 6. Anti-slip grooves; 7. Ladder beam supporting steel plates; 8. Conversion base; 9. Fixing bolts; 10. Perforated baffles; 11. Screws; 12. Adjustment bolts; 13. Limiting plates; 14. Screw sleeves; 15. Stiffening plates; 16. Steel formwork; 17. Steel bottom formwork; 18. Positioning formwork; 19. Positioning nuts; 20. Positioning bolts. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0018] This embodiment first discloses a prefabricated tread plate unit composed of steel and concrete, and its structure is as follows: Figure 1 and Figure 2 As shown, it is mainly composed of a precast concrete step 1, embedded steel ribs 2, a full-thread screw 3 and an adjusting nut 4. Among them, the concrete step 1 is cast from high-strength concrete of C60 and above, which is more cost-effective than using UHPC materials. The concrete step 1 is a flat structure and is easier to process and manufacture. The embedded steel rib 2 is cut from a steel plate, and a tensile support foot is welded perpendicular to the steel plate at one end. The tensile support foot end of the embedded steel rib 2 is embedded in the concrete pedal 1 during casting, and the remaining part is exposed, and a hole is opened at both ends and in the middle of the steel plate at the exposed end. As shown Figure 1 The direction shown is for reference. In this embodiment, two embedded steel ribs 2 are arranged at intervals on the left and right. The two embedded steel ribs 2 are arranged symmetrically, and the length of the exposed end of each embedded steel rib 2 is slightly smaller than the length of the concrete step 1. A full-thread screw 3 is respectively arranged in each group of corresponding holes between the two left and right embedded steel ribs 2. The corresponding holes of the two embedded steel ribs 2 are connected by the full-thread screw 3, and the two ends of the full-thread screw 3 are respectively passed through the vertical plate of the embedded steel rib 2. An adjusting nut 4 is sleeved on both sides of each embedded steel rib 2 on the full-thread screw 3, and a fixing hole 5 is provided at the exposed end of the full-thread screw 3, and a thread is provided on the inner wall of the fixing hole 5. The top surface of the above-mentioned concrete step 1 serves as the treading surface of the stairs. In order to prevent slipping when treading, an anti-slip groove 6 is also provided on the top surface of the concrete step 1 in this embodiment.

[0019] When the prefabricated tread plate unit of the above structure is installed, its structure is as follows Figures 3 to 6 As shown, a fixing mechanism is respectively arranged at both ends of the bottom of the prefabricated tread plate unit, and each fixing mechanism is used to fix the corresponding full-thread screw 3 at the bottom of the supporting concrete step 1. The fixing mechanism is mainly composed of a ladder beam supporting steel plate 7, a conversion base 8, a screw sleeve 14 and fasteners such as bolts.

[0020] like Figure 5As shown, the cross section of the ladder beam supporting steel plate 7 is an L-shaped structure. The ladder beam supporting steel plate 7 is divided into a vertical plate and a horizontal plate. The vertical plate is welded and fixed to the ladder beam of the stairs. The two ends of the horizontal plate of the ladder beam supporting steel plate 7 have fixing holes, and a strip hole is provided between the two fixing holes. The length direction of the strip hole is consistent with the length direction of the concrete step 1. The conversion base 8 is a flat plate. The two ends of the conversion base 8 have strip holes, and the two ends of the strip holes have fixing holes between them. The strip holes of the conversion base 8 correspond to the fixing holes on the horizontal plate of the ladder beam supporting steel plate 7. The fixing holes of the conversion base 8 correspond to the strip holes of the horizontal plate of the ladder beam supporting steel plate 7. The top of the conversion base 8 is spaced apart with a limit plate 13. The limit plate 13 is perpendicular to the conversion base 8 and relatively fixed. A screw sleeve 14 is provided between the two limit plates 13. The screw sleeve 14 is clamped and limited by the limit plates 13 at both ends. The screw sleeve 14 is open at the top and has a U-shaped cross-section. The screw sleeve 14 is used to support the position-limiting full-thread screw 3, so the contact surface between the screw sleeve 14 and the full-thread screw 3 is an arc surface. The conversion base 8 is placed on the top of the horizontal plate of the ladder beam supporting steel plate 7. The strip holes at both ends of the conversion base 8 are fixedly connected with the fixing holes at both ends of the horizontal plate of the ladder beam supporting steel plate 7 by fixing bolts 9. An adjustment bolt 12 is sequentially passed through the strip holes on the horizontal plate of the ladder beam supporting steel plate 7 and the fixing holes on the conversion base 8, so that the top of the adjustment bolt 12 supports the bottom of the screw sleeve 14.

[0021] The fixed installation of the prefabricated tread plate unit can be completed according to the structure given above, and multiple groups of prefabricated tread plate units can be installed in the same way as above to form a Figure 7 In the combined structure shown, in order to strengthen the support strength between the horizontal plate and the vertical plate of the ladder beam supporting steel plate 7, a stiffening plate 15 can also be set between the horizontal plate and the vertical plate. In the above-formed tread plate combined structure, in order to block the gap between adjacent prefabricated tread plate units, in this embodiment, an aluminum perforated baffle plate 10 is also set on the side of each prefabricated tread plate unit. The length of the perforated baffle plate 10 can be consistent with the length of the concrete tread 1. The perforated baffle plate 10 has corresponding holes, and the perforated baffle plate 10 is fixedly installed at the fixing hole at the end of the full-thread screw 3 with screws 11 and limit nuts.

[0022] The installation of the steel-concrete composite prefabricated tread unit designed in this embodiment has a three-way adjustable function. Figure 4The direction shown is for reference. The position of the conversion base 8 can be moved left and right through the strip holes at both ends of the conversion base 8, so as to achieve the left and right position adjustment of the prefabricated tread unit. After the position is adjusted to the right position, the position can be locked and fixed by the fixing bolts 9. The front and rear position adjustment of the prefabricated tread unit can be achieved through the four adjustment nuts 4 on the full-thread screw 3. For the adjustment of the height direction of the prefabricated tread unit, the height of the screw sleeve 14 can be fine-tuned by moving the adjustment bolt 12 upward or downward. This three-way position adjustment can absorb the installation error to the greatest extent, so the installation accuracy requirement is not so high.

[0023] This embodiment also discloses a method for producing the above-mentioned prefabricated tread plate unit, Figure 8 The entire production process is described as follows: Step 1) placing a steel bottom mold 17 with an open top on a steel mold platform 16, wherein a plurality of spaced protrusions are formed on one end of the inner cavity bottom surface of the steel bottom mold 17; Step 2) Then, a pair of L-shaped positioning molds 18 are placed on the steel mold platform 16 and arranged on both sides of the steel bottom mold 17, so that the two positioning molds 18 are clamped and fitted with the steel bottom mold 17; Step 3) connecting two embedded steel ribs 2 through three full-thread screws 3 to form a plane truss, and setting adjustment nuts 4 on both sides of each embedded steel rib 2 on each full-thread screw 3; Step 4) Invert the plane truss in step 3) above the inner cavity of the steel bottom mold 17, open corresponding holes on the vertical plate of the positioning mold 18, and fix the two ends of each full-thread screw 3 to the vertical plates of the positioning mold 18 at both ends with positioning bolts 20. When inverting the plane truss, let the tensile support legs of the embedded steel ribs 2 hang in the air and extend into the inner cavity of the steel bottom mold 17, and set the positioning nuts 19 on the positioning bolts 20 at both ends. After adjusting the position of the plane truss, lock the position by rotating the positioning nuts 19; Step 5) After completing step 4), high-strength concrete is poured into the inner cavity of the steel bottom mold 17, and it is fully vibrated and leveled. After curing, the mold is removed, the positioning bolts 20 are separated from the full-thread screw 3, and the prefabricated tread unit can be disassembled.

[0024] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A prefabricated tread unit, characterized in that: It includes concrete steps, embedded steel ribs, full-threaded screws and adjusting nuts. The concrete steps are of flat structure and are cast with C60 and above high-strength concrete. The embedded steel ribs are cut from steel plates, and a tensile support foot is welded perpendicular to the steel plate at one end of the steel plate. The tensile support foot end of the embedded steel rib is embedded in the concrete step, and the exposed end of the embedded steel rib has holes at least at both ends. Two embedded steel ribs are symmetrically arranged along the width direction of the concrete step, and the full-threaded screw is inserted into the corresponding hole between the two embedded steel ribs. Adjusting nuts are respectively mounted on both sides of the embedded steel rib on the full-threaded screw, and fixing holes are opened on the two end faces of the full-threaded screw.

2. The steel-concrete composite prefabricated tread plate unit according to claim 1, characterized in that: The top surface of the concrete step is provided with an anti-skid groove.

3. The steel-concrete composite prefabricated tread plate unit according to claim 1, characterized in that: A perforated baffle is provided on one side of the lower part of the concrete step, the perforated baffle is vertically arranged with the concrete step, and the perforated baffle is fixed to the fixing hole of the full bolt screw rod by screws.

4. A method for producing a prefabricated tread unit according to any one of claims 1 to 3, characterized in that: It includes the following: Step 1) Place the steel bottom mold on the steel mold table; Step 2) Place a pair of L-shaped positioning molds on the steel mold platform on both sides of the steel bottom mold, so that the two positioning molds are clamped and fit with the steel bottom mold; Step 3) Connect the two embedded steel ribs through a full-thread screw to form a plane truss, and set adjustment nuts on both sides of each embedded steel rib on the full-thread screw; Step 4) Invert the plane truss above the inner cavity of the steel bottom mold, install the two ends of the full-thread screw on the two end positioning molds with positioning bolts, so that the tensile support legs of the embedded steel ribs are suspended in the inner cavity of the steel bottom mold, set the positioning nuts on the positioning bolts, adjust the position of the plane truss, and lock the position with the positioning nuts; Step 5) Pour concrete into the inner cavity of the steel bottom mold and vibrate it to make it smooth. After curing, demould it and separate the positioning bolts from the full-thread screw.

5. The production method according to claim 4, characterized in that: A plurality of spaced protrusions are formed on the bottom surface of the inner cavity of the steel bottom mold.

6. A mounting structure of a prefabricated tread plate unit, characterized in that: It comprises a prefabricated tread unit as described in any one of claims 1 to 3, fixing mechanisms located at both ends of the bottom of the prefabricated tread unit and a perforated baffle located on one side of the lower part of the prefabricated tread unit; the fixing mechanism comprises an L-shaped ladder beam supporting steel plate, a conversion base and a screw sleeve with an open top, the vertical plate of the ladder beam supporting steel plate is fixed to the ladder beam, the conversion base is fixedly connected to the horizontal plate of the ladder beam supporting steel plate, the relative position of the conversion base and the horizontal plate of the ladder beam supporting steel plate is adjustable, a limit plate is arranged at intervals on the top of the conversion base, the limit plate is perpendicular to the conversion base, screw sleeves are clamped between the limit plates, the full-threaded screws at both ends of the prefabricated tread unit are supported and limited by the screw sleeves, the perforated baffle is arranged perpendicular to the concrete tread, and the perforated baffle is fixed to the fixing hole of the full-threaded screw by screws.

7. The installation structure of a prefabricated tread unit according to claim 6, characterized in that: The horizontal plate of the ladder beam supporting steel plate has fixing holes at both ends, and a strip hole is provided between the fixing holes at both ends; strip holes are provided at both ends of the conversion base, and a fixing hole is provided between the strip holes at both ends; the conversion base and the horizontal plate of the ladder beam supporting steel plate are fixedly connected by fixing bolts, and the adjusting bolts are passed through the strip holes on the horizontal plate of the ladder beam supporting steel plate and the fixing holes on the conversion base in sequence to support the bottom of the screw sleeve.

8. The installation structure of a prefabricated tread unit according to claim 6, characterized in that: The contact surface between the screw sleeve and the full-thread screw is an arc surface.

9. The installation structure of a prefabricated tread unit according to claim 6, characterized in that: The perforated baffle is an aluminum plate.

10. The installation structure of a prefabricated tread unit according to claim 6, characterized in that: The horizontal plate and the vertical plate of the ladder beam supporting steel plate are connected by a stiffening plate.

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