A precast staircase with low mold opening cost and its manufacturing method

Abstract

The present invention relates to a precast staircase with low mold opening cost and a manufacturing method thereof, including a precast flight of stairs, a post-cast stair beam, and a connecting platform; the precast flight of stairs includes a number of stair flight units that are sequentially and staggeredly stacked from bottom to top. After the stair flight units are clamped and fixed, the beam steel cage of the post-cast stair beam is placed and connected to the bent part extending from the inclined surface, and then concrete is cast at the beam steel cage to form the post-cast stair beam; the connecting platforms are respectively arranged at the top and bottom of the precast flight of stairs, and the connection between the connecting platform and the post-cast stair beam is realized synchronously by casting concrete at the beam steel cage; a connecting through-hole leading to the inclined surface is provided on the tread surface of the stair flight unit, and a hoisting embedded part extending to the post-cast stair beam is provided in the connecting through-hole. The present invention optimizes the manufacturing method of the precast flight of stairs, adopts stair flight units with a right-angled trapezoidal cross-section, and controls the lengths of the upper bottom surface and the lower bottom surface of the stair flight unit by controlling the slope of the inclined surface in the stair flight unit, so as to achieve the specified step height, and the overall production cost is low.

Description

Technical Field

[0001] The present invention relates to the field of precast stairs, in particular to a precast stair with low mold opening cost and its manufacturing method. Background Art

[0002] At present, the technology of precast stairs has been quite popular, and many patents have disclosed different types of precast stairs. For example, CN208220036U discloses a precast stair. However, the traditional precast stairs mainly have the following problems. For precast stairs in different types of projects, due to the differences in the total height of the stairs and the height of the steps, special molds need to be customized for pouring. Since the stairs themselves are not regular building components, different molds need to be customized for different projects or even different floors to pour the precast stairs, and the mold opening cost significantly increases the cost of the precast stairs.

[0003] Therefore, many designs consider setting up split precast stairs, that is, the stair runs and precast stair run supports (such as stair beams and stair floors) are formed separately and then assembled and installed. For example, CN105804339A discloses a thin web beam type precast stair with separated steps and stair sections and its installation method, CN108661255A discloses a combined precast stair and its production method, CN109386097A discloses a precast stair and a building, CN114347216A discloses a precast stair and its production and construction method, etc.

[0004] It can be seen from the above patent documents that generally, the stair runs in split stairs are either zigzag or the stair runs are divided into several triangular stair run units according to the number of steps. However, the existing split stairs still have the following problems. (1) Once the stair run units are formed, they cannot be adjusted. If the construction drawings need to be adjusted or there are errors at the construction site, the already made stair runs or stair run units will be invalidated in batches. (2) When adjacent stair run units are placed on the precast stair run supports, there are gaps between adjacent stair run units, and it is easy to leak slurry during pouring, resulting in problems such as poor integrity and difficulty in forming of the final product. Summary of the Invention

[0005] The purpose of the present invention is to provide a precast stair with low mold opening cost and its manufacturing method, which optimizes the manufacturing method of the precast stair runs and the connection method between the precast stair runs and the post-cast stair beams and connection platforms, so that only one set of molds is required to adapt to the production of precast stairs of different specifications, reducing the mold opening cost.

[0006] The present invention is realized through the following technical solutions: A precast stair with low mold opening cost includes precast stair runs, post-cast stair beams, and connection platforms;

[0007] The precast stair flight includes a number of stair flight units that are sequentially and staggeredly stacked from bottom to top. The stair flight units are reinforced concrete blocks with a right trapezoidal cross-section on the side, and the slope of the hypotenuse of the right trapezoid is the same. Among them, the surface corresponding to the short bottom side of the right trapezoid is the short bottom surface, the surface corresponding to the long bottom side of the right trapezoid is the long bottom surface, the surface corresponding to the right angle side is the tread surface, the surface corresponding to the hypotenuse is the inclined surface, and the surfaces at both the left and right ends are the side surfaces. Except for the top stair flight unit, the short bottom surface of any stair flight unit closely adheres to the long bottom surface of the adjacent stair flight unit, and the left and right side surfaces of all stair flight units in the precast stair flight are aligned. Multiple groups of connecting steel bars extending in the left-right direction are embedded in the inclined surface. Both ends of the connecting steel bars are provided with bent portions embedded in the inclined surface, and the bent portions are extended out of the inclined surface by turning the bent portions.

[0008] The post-cast stair beam is a reinforced concrete structure and is provided on the left and right sides of the bottom surface of the precast stair flight. A number of stair flight units that are sequentially and staggeredly stacked from bottom to top are clamped and fixed by a fixture. At the same time, the beam steel cage of the post-cast stair beam is connected to the bent portion extending out of the inclined surface.

[0009] The connecting platform is a reinforced concrete structure and is provided at the top and bottom of the precast stair flight. The platform steel cage in the connecting platform is connected to the beam steel cage.

[0010] The synchronous connection of the post-cast stair beam with the precast stair flight and the connecting platform is realized by laying beam formwork outside the beam steel cage and pouring concrete.

[0011] Among them, connecting through-holes leading to the inclined surface are provided on the tread surfaces of some stair flight units, and lifting embedded parts extending to the post-cast stair beam are provided in the connecting through-holes.

[0012] A manufacturing method of a precast staircase with low mold opening cost includes the following steps;

[0013] S1. According to the total height of the staircase and the step height, confirm the number of stair flight units and the slope of the partition board in the rectangular mold to control the lengths of the short bottom surface and the long bottom surface of the stair flight unit and the slope of the inclined surface. Among them, the length difference between the short bottom surface and the long bottom surface of adjacent stacked stair flight units is the step height, and the number of stacked stair flight units is determined according to the total height of the staircase.

[0014] S2. Place several stair flight units with the inclined surface facing down. Except for the top stair flight unit, arrange the stair flight units in such a way that the short bottom surface of any stair flight unit closely adheres to the long bottom surface of the adjacent stair flight unit to form a precast stair flight.

[0015] S3. Prepare a fixture, clamp the left and right side surfaces of the precast stair flight with the two clamping plates of the fixture respectively, then pass a through-bolt through the through-holes of the two clamping plates and lock it to clamp the precast stair flight with the two fixtures.

[0016] In S4, the turning fixture turns the inclined surface of the precast stair flight upward, and then turns the bent part of the connecting steel bar so that the bent part extends out of the inclined surface.

[0017] In S5, place the beam steel cage of the post-cast stair beam and connect the bent part. At the same time, place the connecting platform, and connect the platform steel cage of the connecting platform and the beam steel cage. Then lay the beam formwork, and pour concrete in the beam formwork to form the post-cast stair beam. At this time, the post-cast stair beam is connected to the precast stair flight and the connecting platform at the same time.

[0018] In S6, remove the beam formwork, and then turn the turning fixture to make the inclined surface of the precast stair flight face downward, and then remove the fixture to form the precast staircase.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. Optimize the manufacturing method of the precast stair flight. The stair flight unit with a right-angled trapezoidal cross-section is adopted. By controlling the slope of the inclined surface in the stair flight unit, the lengths of the short bottom surface and the long bottom surface in the stair flight unit are controlled. Since the height difference between two adjacent steps is determined by the difference between the short bottom surface and the long bottom surface in adjacent stair flight units, by adjusting the relative positions between adjacent stair flight units, the step height and the total height of the precast stair flight can be adjusted.

[0021] 2. At the same time, since the contact area between adjacent stair flight units is the area of the short bottom surface, the sealing effect is good, which can avoid slurry leakage in the subsequent manufacturing process and enhance the integrity of the precast staircase.

[0022] 3. The cross-section of the stair flight unit is a right-angled trapezoid. Since the slopes of the inclined surfaces are equal, it forms a rectangle after staggered splicing. Therefore, the present invention can complete the pouring and forming of different specifications of stair flight units with only one set of molds, avoiding the situation that traditional precast staircases need to customize templates, and the overall production cost is low.

[0023] 4. The stair flight units in the precast stair flight can be conveniently stacked and combined on a plane. Through the prestress applied by the fixture, the combined stair flight units can be conveniently turned as a whole, and then used as the bottom formwork of the post-cast stair beam.

[0024] 5. In order to facilitate the pouring of the stair flight units in the early process and the connection between the stair flight units and the post-cast stair beam in the subsequent process, connecting steel bars are embedded in the stair flight units here. The two ends of the connecting steel bars are provided with bent parts. When pouring the stair flight units, the bent parts are bent inward and embedded in the inclined surface, which does not affect the pouring of the stair flight units. When manufacturing the precast staircase subsequently, by turning the bent parts, the bent parts extend out of the inclined surface, which is convenient for the subsequent connection between the beam steel cage and the bent parts, so that when pouring subsequently, the post-cast stair beam and the precast stair flight can be connected to form an integral body.

[0025] 6. Connecting through holes are provided on the stair flight units, and hoisting embedded parts are preset in the connecting through holes for installing lifting rings subsequently to facilitate the hoisting of the precast staircase. Brief Description of the Drawings

[0026] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 It is a schematic diagram of the structure of the flight unit;

[0028] Figure 3 It is a schematic diagram of pouring the flight unit through a rectangular mold in Step 1;

[0029] Figure 4 It is a schematic diagram of arranging the flight units to form a precast flight and placing fixtures in Step 2;

[0030] Figure 5 It is a schematic diagram of the fixture clamping the precast flight and installing the through bolts in Step 3;

[0031] Figure 6 It is a schematic diagram of tightening the through bolts to clamp the precast flight by the fixture in Step 3;

[0032] Figure 7 It is a schematic diagram of flipping the precast flight in Step 4;

[0033] Figure 8 It is a schematic diagram after placing the beam reinforcement cage and the platform reinforcement cage and installing the beam formwork and the platform formwork in Step 5.

[0034] Figure 9 For Figure 8 Side perspective view;

[0035] Figure 10 It is a schematic diagram of removing the beam formwork, flipping the precast flight, and removing the fixture in Step 6;

[0036] Figure 11 It is a schematic diagram after installing lifting rings on the precast flight;

[0037] Figure 12 It is a schematic diagram of using a precast connection platform in Step 5;

[0038] Figure 13 For Figure 12 Schematic diagram after adding beam formwork on the basis of;

[0039] Figure 14 For Figure 13 Side perspective view;

[0040] Figure 15 It is a reference diagram of the states before and after the change of the bent part of the connecting steel bars in the flight unit.

[0041] Description of reference numerals: 1 precast stair flight, 2 cast-in-place stair beam, 21 beam steel reinforcement cage, 3 connecting platform, 31 platform steel reinforcement cage, 32 platform connecting reinforcement, 33 installation through-hole, 34 platform part, 35 platform beam, 4 stair flight unit, 41 short bottom surface, 42 long bottom surface, 43 tread surface, 44 inclined surface, 45 side surface, 46 connecting reinforcement, 461 bent part, 47 connecting through-hole, 48 anti-slip strip, 5 hoisting embedded part, 51 connecting rod, 52 extension rod, 6 lifting ring, 7 rectangular mold, 71 partition board, 8 fixture, 81 through bolt, 82 clamping plate, 83 through-hole, 84 hoisting hole, 91 beam formwork, 92 platform formwork. Detailed implementation mode

[0042] The present invention will be described in detail below with reference to the accompanying drawings:

[0043] As Figure 1 , 2 shown: A precast staircase with a low mold opening cost, including a precast stair flight 1, a cast-in-place stair beam 2 and a connecting platform 3;

[0044] The precast stair flight 1 includes a number of stair flight units 4 that are sequentially and staggeredly stacked from bottom to top. The stair flight unit 4 is a reinforced concrete block with a right-angled trapezoid cross-section on the side, and the slope of the hypotenuse of the right-angled trapezoid is the same; among them, the surface corresponding to the short bottom side of the right-angled trapezoid in the stair flight unit 4 is the short bottom surface 41, the surface corresponding to the long bottom side of the right-angled trapezoid is the long bottom surface 42, the surface corresponding to the right angle side is the tread surface 43, the surface corresponding to the hypotenuse is the inclined surface 44, and the left and right end surfaces are both side surfaces 45; except for the top stair flight unit 4, the short bottom surface 41 in any stair flight unit 4 is closely attached to the long bottom surface 42 of the adjacent stair flight unit 4, and the left and right side surfaces 45 of all the stair flight units 4 in the precast stair flight 1 are aligned; A number of groups of connecting reinforcements 46 extending left and right are embedded in the inclined surface 44. Both ends of the connecting reinforcement 46 are provided with bent parts 461 embedded in the inclined surface 44, and the bent parts 461 are extended out of the inclined surface 44 by turning over the bent parts 461;

[0045] The cast-in-place stair beam 2 is a reinforced concrete structure and is arranged on the left and right sides of the bottom surface of the precast stair flight 1. A number of stair flight units 4 that are sequentially and staggeredly stacked from bottom to top are clamped and fixed by a fixture 8. At the same time, the beam steel reinforcement cage 21 of the cast-in-place stair beam 2 is connected to the bent part 461 extending out of the inclined surface 44;

[0046] The connecting platform 3 is a reinforced concrete structure and is arranged at the top and bottom of the precast stair flight 1. The platform steel reinforcement cage 31 in the connecting platform 3 is connected to the beam steel reinforcement cage 21;

[0047] The synchronous connection of the cast-in-place stair beam 2 with the precast stair flight 1 and the connecting platform 3 is realized by laying the beam formwork 91 outside the beam steel reinforcement cage 21 and pouring concrete;

[0048] Among them, a connection through-hole 47 leading to the inclined surface 44 is provided on the tread surface 43 of some of the ladder run units 4, and a hoisting embedded part 5 extending to the post-cast ladder beam 2 is provided in the connection through-hole 47.

[0049] The biggest feature of the present invention is that the precast ladder runs designed are formed by sequentially and staggeredly stacking a number of ladder run units 4. The cross-section of the ladder run unit 4 is a right trapezoid. And the slope of the hypotenuse of the right trapezoid is the same. Therefore, when the inclined surfaces of two ladder run units 4 are rotationally fitted, a rectangular structure will be formed. Thus, the ladder run unit 4 of the present invention can be formed by placing an isolation board in a rectangular mold and pouring.

[0050] The sequential and staggered stacking of a number of ladder run units 4 has the following effects. First, it ensures the tight contact between adjacent ladder run units 4. Since there is a process of pouring concrete later, the adjacent ladder run units 4 are in surface contact, ensuring that there will be no leakage of mortar during the subsequent concrete pouring process. In addition, except for the top ladder run unit, the short bottom surface in any ladder run unit closely adheres to the long bottom surface of the adjacent ladder run unit, and the length difference between the short bottom surface and the long bottom surface is the height of the step.

[0051] Ideally, only according to the preliminary design drawings, calculate the height of the steps and the number of steps. When forming the ladder run unit 4, only the slope of the isolation board needs to be considered. In this way, when sequentially and staggeredly stacking the ladder run units 4, only need to ensure that the inclined surfaces 44 of the ladder run units 4 are all located on the same plane to form the bottom surface of the precast ladder run 1.

[0052] However, if there are deviations in the subsequent construction drawings or at the construction site, resulting in the need to adjust the step height, at this time, the inclined surfaces 44 of the ladder run units 4 cannot be located on the same plane, and it is necessary to appropriately adjust the contact surface size between adjacent ladder run units 4, that is, adjust the length difference between the short bottom surface and the long bottom surface. The bottom surface of the finally formed precast ladder run 1 will have unevenness, which can be leveled by plastering or other methods to ensure its aesthetics. Of course, it is also possible not to perform the leveling treatment.

[0053] In addition, it should also be noted that the core of the present invention is to adjust the contact area between adjacent ladder run units 4, that is, to adjust the length difference between the short bottom surface and the long bottom surface in the ladder run unit 4. Therefore, if there is a situation where the length difference needs to be adjusted, only the first placed ladder run unit 4 needs to be placed obliquely, and the subsequent ladder run units 4 will naturally be placed obliquely on the premise of ensuring tight contact. At this time, the adjustment of the length difference between the short bottom surface and the long bottom surface in the ladder run unit 4 can be completed.

[0054] To improve the strength of the flight unit, it is necessary to consider adding a stringer structure later. However, due to the uncontrollable length of the precast flight, the stringer structure here is cast-in-place later. The connecting platform itself is a relatively standard product, so the connecting platform can be precast or cast-in-place.

[0055] Considering the hoisting requirements of the subsequent precast building, connecting through-holes 47 are provided in the flight unit. Hoisting embedded parts 5 extending to the cast-in-place stringer 2 are arranged in the connecting through-holes 47. The hoisting embedded parts 5 extending to the cast-in-place stringer 2 can ensure its connection strength and prevent the situation of the flight unit and the cast-in-place stringer from disassembling during later hoisting.

[0056] As Figure 3 shown: The flight units 4 are formed in pairs in a vertically placed rectangular mold 7. A partition board 71 is placed in the rectangular mold 7 to divide the rectangular mold 7 into two casting spaces with right trapezoidal cross-sections. By adjusting the slope and position of the partition board 71, the lengths of the short bottom surface 41 and the long bottom surface 42 of the flight unit 4 and the slope of the inclined surface 44 are controlled, so as to adjust the casting space. After placing the connecting steel bars 46 in the casting space, concrete is poured and after solidification, the rectangular mold 7 is removed, and the flight unit 4 is demolded.

[0057] The above design can ensure that a set of rectangular molds 7 can produce flight units 4 with right trapezoidal cross-sections by adjusting the slope of the partition board 71. After the subsequent flight units 4 are assembled, they can meet the requirements of different step geometric parameters.

[0058] The fixture 8 includes two clamping plates 82 and a through bolt 81. A number of through holes 83 are provided on the clamping plates 82, and hoisting holes 84 are provided at both ends of the clamping plates 82. The two clamping plates 82 are respectively arranged on the left and right sides of the flight units 4 that are staggeredly stacked in sequence from bottom to top. The through bolt 81 passes through the through holes 83 and is tightened to clamp the flight units 4 with the two clamping plates 82. The fixture provides a basis for the subsequent clamping and flipping of the flight units and subsequent pouring.

[0059] Anti-slip strips 48 extending left and right are embedded in the tread surface 43 of the flight unit 4. The anti-slip strips here can also be anti-slip patterns.

[0060] The connecting through-holes 47 are located in the top flight unit 4 and the bottom flight unit 4; sling rings 6 that penetrate into the connecting through-holes 47 and are detachably connected to the hoisting embedded parts 5 are arranged in the connecting through-holes 47.

[0061] The hoisting embedded part 5 and the lifting ring 6 can be disassembled and connected by means of threads. Additionally, the hoisting embedded part 5 includes a connecting rod 51 and an extension rod 52. The connecting rod 51 extends into the connecting through-hole 47, and the extension rod 52 is connected to the tail of the connecting rod 51 and is arranged perpendicular to the connecting rod 51. The extension rod 52 is located within the post-cast stair beam 2.

[0062] The connecting platform 3 is a precast connecting platform 3. Platform connecting bars 32 extending towards the post-cast stair beam 2 are provided on the platform steel reinforcement cage 31 of the connecting platform 3. Since the specifications of the precast stair runs have little influence on the connecting platform, the connecting platform 3 can also be made in a precast manner. Considering that only the stair beam is cast in-situ in the entire technological process, platform connecting bars 32 extending towards the post-cast stair beam 2 are provided on the platform steel reinforcement cage 31 of the connecting platform 3 to connect with the beam steel reinforcement cage, ensuring the connection between the post-cast stair beam and the connecting platform when the post-cast stair beam is poured.

[0063] The connecting platform 3 can be designed as precast or in-situ cast.

[0064] The connecting platform 3 is an in-situ cast connecting platform 3. The two ends of the beam steel reinforcement cage 21 of the post-cast stair beam 2 extend into the corresponding platform steel reinforcement cages 31 and are connected to each other.

[0065] The connecting platform 3 is divided into a platform part 34 and platform beams 35. The platform beams 35 are respectively arranged on the left and right sides of the bottom surface of the platform part 34. The platform beams 35 can enhance the strength of the connecting platform.

[0066] An installation through-hole 33 penetrating up and down is provided on the connecting platform 3. The installation through-hole provides a basis for the subsequent connection and installation of the precast staircase with the limiting rods on the building body.

[0067] Additionally, the hoisting embedded part 5 includes a connecting rod 51 and an extension rod 52. The connecting rod 51 extends into the connecting through-hole 47, and the extension rod 52 is connected to the tail of the connecting rod 51 and is arranged perpendicular to the connecting rod 51. The extension rod 52 is located within the post-cast stair beam 2.

[0068] As Figure 3-13 shown: A manufacturing method of a precast staircase with low mold opening cost includes the following steps;

[0069] S1. According to the total height of the staircase and the step height, confirm the number of stair run units 4 and the slope of the partition board 71 within the rectangular mold 7 to control the lengths of the short bottom surface 41, the long bottom surface 42, and the slope of the inclined surface 44 in the stair run unit 4. The length difference between the short bottom surface 41 and the long bottom surface 42 in adjacent stacked stair run units 4 in the stair run unit 4 is the step height, and the number of stacked stair run units 4 is determined according to the total height of the staircase; As Figure 3 shown.

[0070] S2. Place the slopes 44 of several flight units 4 facing downwards. Except for the topmost flight unit 4, arrange the flight units 4 in such a way that the short bottom surface 41 in any flight unit 4 closely adheres to the long bottom surface 42 of the adjacent flight unit 4 to form the precast flight 1, as shown in Figure 4 .

[0071] S3. Prepare the fixture 8. Clamp the left and right side surfaces 45 of the precast flight 1 with the two clamping plates 82 of the fixture 8 respectively. Then, pass the through bolts 81 through the through holes 83 in the two clamping plates 82 and tighten them to clamp the precast flight 1 with the two fixtures 8, as shown in Figure 5 and 6 .

[0072] S4. Flip the fixture 8 to make the slope 44 of the precast flight 1 face upwards. Then, flip the bent portion 461 of the connecting steel bar 46 so that the bent portion 461 extends out of the slope 44, as shown in Figure 7 . The flipping and changing state of the bent portion 461 can be referred to in Figure 15 .

[0073] S5. Place the beam steel cage 21 of the post-cast ladder beam 2 and connect the bent portion 461. At the same time, place the connecting platform 3, and connect the platform steel cage 31 of the connecting platform 3 with the beam steel cage 21. Then, lay the beam formwork 91 and pour concrete in the beam formwork 91 to form the post-cast ladder beam 2. At this time, the post-cast ladder beam 2 connects the precast flight 1 and the connecting platform 3 simultaneously, as shown in Figure 8 and 9 and Figures 12, 13, 14

[0074] S6. Demolish the beam formwork 91. Then, flip the fixture 8 to make the slope 44 of the precast flight 1 face downwards and then remove the fixture 8 to form the precast staircase, as shown in Figure 10 .

[0075] It should be noted that in S5, it is divided into S5A and S5B according to whether the connecting platform 3 is precast;

[0076] S5A. If the connecting platform 3 is precast, place the beam steel cage 21 of the post-cast ladder beam 2 and connect the bent portion 461. At the same time, place the precast connecting platform 3. The platform steel cage 31 of the connecting platform 3 is provided with platform connecting bars 32 extending towards the post-cast ladder beam 2. The platform connecting bars 32 are connected with the beam steel cage 21. Then, lay the beam formwork 91 and pour concrete in the beam formwork 91 to form the post-cast ladder beam 2. At this time, the post-cast ladder beam 2 connects the precast flight 1 and the connecting platform 3 simultaneously, as shown in Figure 8 and 9 .

[0077] For S5B, if the connecting platform 3 is not prefabricated, place the beam reinforcement cage 21 of the post-cast stair beam 2 and connect the bent part 461. At the same time, place the non-prefabricated connecting platform 3. Specifically, placing the connecting platform 3 means placing the platform reinforcement cage 31 of the connecting platform 3. The beam reinforcement cage 21 extends to the platform reinforcement cage 31 and is connected to the platform reinforcement cage 31. Then, lay the beam formwork 91 and the platform formwork 92, and pour concrete in the beam formwork 91 and the platform formwork 92 to form the post-cast stair beam 2 and the connecting platform 3 respectively. At this time, the post-cast stair beam 2 is connected to the precast stair flight 1 and the connecting platform 3 simultaneously. As Figure 12-14 shown.

[0078] Finally, it should be noted that the above are only the preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A prefabricated staircase with low mold opening cost, characterized in that: It comprises a prefabricated ladder runner (1), a post-cast ladder beam (2) and a connecting platform (3); The prefabricated stair run (1) comprises a plurality of stair run units (4) stacked in a staggered manner from the bottom to the top, wherein the stair run units (4) are reinforced concrete blocks with a right-angled trapezoidal side section and the slopes of the hypotenuses of the right-angled trapezoids are consistent; wherein the surface of the stair run unit (4) corresponding to the short bottom side of the right-angled trapezoid is the short bottom surface (41), the surface corresponding to the long bottom side of the right-angled trapezoid is the long bottom surface (42), the surface corresponding to the right-angled side is the stepping surface (43), the surface corresponding to the hypotenuse is the oblique surface (44), and the surfaces at the left and right ends are both side surfaces (45); Except for the ladder run unit (4) at the top, the short bottom surface (41) in any ladder run unit (4) is in close contact with the long bottom surface (42) of the adjacent ladder run unit (4), and the left and right side surfaces (45) of all the ladder run units (4) in the prefabricated ladder run (1) are aligned; a plurality of groups of connecting steel bars (46) extending in left and right directions are embedded in the inclined surface (44), and both ends of the connecting steel bars (46) are provided with bending portions (461) embedded in the inclined surface (44), and the bending portions (461) are extended out of the inclined surface (44) by turning the bending portions (461); The post-cast ladder beam (2) is a reinforced concrete structure and is disposed on the left and right sides of the bottom surface of the prefabricated ladder run (1). A plurality of ladder run units (4) stacked in sequence from the bottom to the top are clamped and fixed by a clamp (8). At the same time, a beam reinforcement cage (21) of the post-cast ladder beam (2) is placed and connected to a bent portion (461) extending out of the inclined surface (44); The connecting platform (3) is a reinforced concrete structure and is disposed at the top and bottom of the prefabricated staircase (1). The platform steel cage (31) in the connecting platform (3) is connected to the beam steel cage (21); The post-cast ladder beam (2) is synchronously connected with the prefabricated ladder runner (1) and the connection platform (3) by laying a beam template (91) outside the beam reinforcement cage (21) and pouring concrete simultaneously; A connecting through hole (47) leading to the inclined surface (44) is provided on the step surface (43) of a part of the ladder run unit (4), and a hoisting embedded part (5) extending to the post-cast ladder beam (2) is provided in the connecting through hole (47).

2. A prefabricated staircase with low mold opening cost according to claim 1, characterized in that: The ladder run units (4) are formed in pairs in a vertically placed rectangular mold (7). An isolation plate (71) is placed in the rectangular mold (7) to divide the rectangular mold (7) into two casting spaces with right-angled trapezoidal cross-sections. The length of the short bottom surface (41) and the long bottom surface (42) of the ladder run unit (4) and the slope of the inclined surface (44) are controlled by adjusting the slope and position of the isolation plate (71), thereby adjusting the casting space. After the connecting steel bars (46) are placed in the casting space, concrete is poured and solidified, and the rectangular mold (7) is removed to demould to form the ladder run unit (4).

3. A prefabricated staircase with low mold opening cost according to claim 1, characterized in that: The clamp (8) comprises two clamping plates (82) and a through-hole screw (81); a plurality of through-holes (83) are provided on the clamping plates (82); and lifting holes (84) are provided at both ends of the clamping plates (82); the two clamping plates (82) are arranged on the left and right sides of the ladder run unit (4) which is stacked and staggered in sequence from the bottom to the top; the through-hole screw (81) passes through the through-holes (83) and is locked, so that the two clamping plates (82) clamp the ladder run unit (4).

4. The prefabricated staircase with low mold opening cost according to claim 1, characterized in that: The tread surface (43) of the ladder running unit (4) is embedded with an anti-slip strip (48) extending in the left and right directions.

5. The prefabricated staircase with low mold opening cost according to claim 1, characterized in that: The connecting through holes (47) are located at the top ladder run unit (4) and the bottom ladder run unit (4); a lifting ring (6) is provided in the connecting through hole (47) and is inserted into the connecting through hole (47) and is detachably connected to the lifting embedded part (5).

6. The prefabricated staircase with low mold opening cost according to claim 1, characterized in that: The connection platform (3) is a prefabricated connection platform (3), and a platform reinforcement cage (31) of the connection platform (3) is provided with platform connection bars (32) extending in the direction of the back-cast ladder beam (2).

7. The prefabricated staircase with low mold opening cost according to claim 1, characterized in that: The connection platform (3) is a cast-in-place connection platform (3), and both ends of the beam reinforcement cage (21) of the post-cast ladder beam (2) extend into the corresponding platform reinforcement cage (31) and are connected to each other.

8. The prefabricated staircase with low mold opening cost according to claim 1, characterized in that: The hoisting embedded part (5) comprises a connecting rod (51) and an extension rod (52), wherein the connecting rod (51) extends into the connecting through hole (47), the extension rod (52) is connected to the rear end of the connecting rod (51) and is arranged vertically with the connecting rod (51), and the extension rod (52) is located in the post-cast ladder beam (2).

9. A method for manufacturing a prefabricated staircase with low mold opening cost according to any one of claims 1 to 8, characterized in that: The steps include: S1, according to the total height of the stairs and the step height, determine the number of stair run units (4) and the slope of the isolation plate (71) in the rectangular mold (7) to control the length of the short bottom surface (41), the long bottom surface (42) and the slope of the inclined surface (44) in the stair run unit (4), wherein the length difference between the short bottom surface (41) and the long bottom surface (42) in the adjacent stacked stair run units (4) is the step height, and the number of stacked stair run units (4) is determined according to the total height of the stairs; S2, with the inclined surfaces (44) of a plurality of ladder run units (4) facing downward, except for the ladder run unit (4) at the top, the ladder run units (4) are arranged in such a manner that the short bottom surface (41) of any ladder run unit (4) is in close contact with the long bottom surface (42) of an adjacent ladder run unit (4), thereby forming a prefabricated ladder run (1); S3, prepare a clamp (8), and clamp the left side (45) and the right side (45) of the prefabricated ladder run (1) with two clamping plates (82) of the clamp (8), respectively, and then pass the through-holes (83) of the two clamping plates (82) through the through-holes (83) and lock them, so that the two clamps (8) clamp the prefabricated ladder run (1); S4, turning over the clamp (8) so that the inclined surface (44) of the prefabricated ladder run (1) faces upward, and then turning over the bent portion (461) of the connecting steel bar (46) so that the bent portion (461) extends out of the inclined surface (44); S5, placing the beam reinforcement cage (21) of the post-cast ladder beam (2) and connecting the bent portion (461), placing the connecting platform (3) and connecting the platform reinforcement cage (31) of the connecting platform (3) to the beam reinforcement cage (21), then laying the beam formwork (91), pouring concrete in the beam formwork (91) to form the post-cast ladder beam (2), at which point the post-cast ladder beam (2) is simultaneously connected to the prefabricated ladder run (1) and the connecting platform (3); S6, removing the beam template (91), then turning over the clamp (8) so that the inclined surface (44) of the prefabricated staircase (1) faces downward, and then removing the clamp (8) to form the prefabricated staircase.

10. The method for manufacturing a prefabricated staircase with low mold opening cost according to claim 9, characterized in that: In S5, it is divided into S5A and S5B according to whether the connection platform (3) is prefabricated; S5A, if the connection platform (3) is prefabricated, the beam reinforcement cage (21) of the post-cast ladder beam (2) is placed and connected to the bent portion (461), and the prefabricated connection platform (3) is placed at the same time, wherein the platform reinforcement cage (31) of the connection platform (3) is provided with a platform connection rib (32) extending in the direction of the post-cast ladder beam (2), and the platform connection rib (32) and the beam reinforcement cage (21) are connected, and then the beam formwork (91) is laid, and concrete is poured in the beam formwork (91) to form the post-cast ladder beam (2), at which time the post-cast ladder beam (2) is simultaneously connected to the prefabricated ladder run (1) and the connection platform (3); S5B, if the connection platform (3) is not prefabricated, the beam reinforcement cage (21) of the post-cast ladder beam (2) is placed and connected to the bent portion (461), and the non-prefabricated connection platform (3) is placed at the same time, wherein placing the connection platform (3) specifically involves placing the platform reinforcement cage (31) of the connection platform (3), the beam reinforcement cage (21) extending to the platform reinforcement cage (31) and connected to the platform reinforcement cage (31), and then laying the beam formwork (91) and the platform formwork (92), and pouring concrete in the beam formwork (91) and the platform formwork (92) to form the post-cast ladder beam (2) and the connection platform (3), respectively, at which time the post-cast ladder beam (2) is simultaneously connected to the prefabricated ladder run (1) and the connection platform (3).

Images