Prefabricated stairway and method of construction thereof

Abstract

The application discloses a prefabricated stair and a construction method thereof, and relates to the technical field of fabricated building construction. The first connecting mechanism is anchored in the installation groove on the ladder surface and extends to the side to form a welding position. The welding operation surface is shifted from the narrow end face of the ladder section plate in the traditional process to the side open area of the ladder section plate, avoiding quality defects such as incomplete fusion of the weld and slag inclusion caused by limited operation space, and ensuring the directness and stability of the stress transmission path. The installation groove is distributed on the same side along the length direction of the ladder body, so that only one side alignment needs to be concerned during hoisting and positioning, the difficulty of installation and positioning is reduced, the labor intensity of repeated adjustment is reduced, and the construction efficiency is improved. The risk of ladder section knocking or disconnection in the traditional sliding connection is avoided, and the reliability of the connection node and the safety of the structure as a whole are ensured.

Description

Technical Field

[0001] This invention relates to the field of prefabricated construction technology, and in particular to a prefabricated staircase and its construction method. Background Technology

[0002] With the deepening of industrialization in the construction industry, prefabricated building technology has been widely applied and rapidly developed. As an important vertical transportation component in building structures, prefabricated stairs have gradually replaced traditional cast-in-place stair construction techniques due to their advantages such as high standardization, good molding quality, and less on-site wet work. In the practical application of prefabricated stairs, the design of the connection nodes between them and the main structure (especially cast-in-place shear wall structures) has evolved from simple lap supports to pursuing structural cooperation. The core technology has always revolved around how to improve the reliability of the connection, simplify the on-site operation process, and ensure the overall safety of the structure under seismic loads.

[0003] Currently, the common construction method for connecting precast stairs to cast-in-place shear walls is the "fixed hinge + sliding hinge" connection method. Typically, holes are reserved at one end of the stair slab and the reinforcing bars of the rest platform cantilever beam are grouted for fixation, while the other end is directly connected to the steel plate on the corbel through a pre-embedded steel plate or by using bolts to limit the sliding end.

[0004] However, existing connection construction technology uses direct welding of end embedded parts. Since the welding position is mostly located on the narrow end face of the stair section plate, the working space is limited, which makes it difficult to guarantee the quality of the weld and the force transmission path is not direct. At the same time, the connection method generally suffers from difficulties in installation and positioning and low construction efficiency. Construction workers need to repeatedly adjust the position of the stair section on the narrow working surface to align the embedded parts or dowel bars, which not only increases the labor intensity, but also makes it difficult to ensure the long-term stability of the force transmission of the subsequent connection nodes. Summary of the Invention

[0005] The main objective of this invention is to propose a prefabricated staircase and its construction method, aiming to solve the problems of existing connection construction technologies that use direct welding of end embedded parts. Due to the limited working space caused by the welding positions being mostly located on the narrow end faces of the stair slabs, the quality of the welds is difficult to guarantee, and the force transmission path is not direct. At the same time, the connection method generally suffers from difficulties in installation and positioning, and low construction efficiency. Construction workers need to repeatedly adjust the position of the stair slabs on the narrow working surface to align with the embedded parts or reinforcing bars, which not only increases the intensity of manual labor, but also makes it difficult to ensure the long-term stability of the force transmission of subsequent connection nodes.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a prefabricated staircase, comprising: The ladder body has multiple mounting grooves formed on its ladder surface. All the mounting grooves are distributed at intervals along the length extension direction of the ladder body on the same side of the ladder body, and a pre-embedded hole is formed at the bottom of each mounting groove. Multiple first connecting mechanisms are provided, the number of which corresponds to the number of mounting slots and are installed one-to-one. Each first connecting mechanism is anchored to the ladder body through a corresponding pre-embedded hole. The first connecting mechanism extends out of the ladder body along its width and forms a welding position. Multiple second connecting mechanisms are provided, the number of which is the same as that of the first connecting mechanisms. The second connecting mechanisms are welded to the corresponding welding positions. The second connecting mechanisms are pre-embedded in the external cast-in-place shear wall located on one side of the ladder body, so that the ladder body and the external cast-in-place shear wall are connected as one unit.

[0007] In one embodiment, the first connecting mechanism includes: Angle steel, which is installed in the mounting groove, has a first side plate and a second side plate that are connected to each other and integrally formed. The first side plate extends outward from the ladder body along the width direction of the ladder body and forms the welding position. The second side plate is provided with a through hole that runs vertically through the ladder body. The through hole corresponds to the position of the pre-embedded hole. An embedded component, which vertically passes through the through hole and extends into the corresponding embedded hole, to anchor the angle steel to the ladder body; and, A filler is provided to fill the mounting groove so as to pre-embed the angle steel in the mounting groove.

[0008] In one embodiment, the embedded component includes: A binder block, the binder block filling the pre-embedded hole; and, An embedded screw rod is inserted into the through hole and one end of the screw rod is anchored in the adhesive block to anchor the angle steel to the ladder body.

[0009] In one embodiment, the adhesive block is made of cement mortar or structural adhesive.

[0010] In one embodiment, the filler is made of cement mortar.

[0011] In one embodiment, the second connecting mechanism includes: Multiple connecting bolts are provided for connecting to the reinforcement cage of the external cast-in-place shear wall, and all connecting bolts extend outward along the thickness direction of the external cast-in-place shear wall to form an installation area on one side of the external cast-in-place shear wall; and, An anchor plate, which is connected to the connecting screw and located within the installation area, has one side of the anchor plate facing the angle steel for welding to the welding position of the angle steel.

[0012] In one embodiment, a filling gap is formed between the ladder body and the external cast-in-place shear wall, and a gap sealing component is filled in the filling gap.

[0013] In one embodiment, the gap sealing assembly includes a fireproof rock wool board, two PE rods and two layers of weather-resistant structural adhesive. The fireproof rock wool board is filled in the gap, and one of the PE rods is filled on each side of the fireproof rock wool board in the height direction. On the side of each PE rod away from the fireproof rock wool board, a layer of the weather-resistant structural adhesive is filled.

[0014] Based on the same technical concept, in a second aspect, the present invention also proposes a construction method for a prefabricated staircase, characterized in that it is used for constructing the prefabricated staircase described in the first aspect; The construction method includes the following steps: Provides an external load-bearing beam and an external cast-in-place shear wall that have reached a preset strength; wherein, the second connecting mechanism is pre-embedded in the external cast-in-place shear wall; The ladder body is hoisted and installed on the external load-bearing beam, so that the side of the ladder body with the installation groove is opposite to the external cast-in-place shear wall, and the filling gap is formed between the ladder body and the external cast-in-place shear wall. The first connecting mechanism is installed in each of the mounting slots; Each of the first connecting mechanisms is welded together with the corresponding second connecting mechanism. The gaps in the filling are sealed to complete the construction of the prefabricated staircase.

[0015] In one embodiment, the step of sealing the filling gap to complete the construction of the prefabricated staircase includes: Mortar material is filled into the top opening of the mounting groove to connect the ladder body to the external cast-in-place shear wall as a whole; Fireproof rock wool boards are embedded in the filling gaps; Install a PE rod on each side of the fireproof rock wool board along its height. Weather-resistant sealant is filled on the side of each PE rod away from the fireproof rock wool board to complete the sealing of the filling gap.

[0016] The technical solution of this invention, by setting up a ladder body, a first connecting mechanism, and a second connecting mechanism, allows for efficient welding during use. Because the first connecting mechanism is anchored in the mounting groove on the ladder surface and extends laterally to form a welding position, the welding work surface is shifted from the narrow end face of the ladder section in traditional processes to the open side area of ​​the ladder section. This change in spatial position allows welders to perform overhead or flat welding in a comfortable posture, effectively avoiding quality defects such as incomplete weld fusion and slag inclusions caused by limited operating space, and ensuring the directness and stability of the force transmission path. Secondly, the structural layout of the mounting grooves being spaced along the length of the ladder body on the same side means that only one side needs to be aligned during hoisting and positioning. Compared to aligning holes with reinforcing bars at both ends or leveling with pre-embedded parts on both sides, this significantly reduces the difficulty of installation and positioning and the labor intensity of repeated manual adjustments, greatly improving construction efficiency. Finally, the second connecting mechanism, pre-embedded in the shear wall, is rigidly connected to the first connecting mechanism on the ladder body through welding, integrating the originally separate prefabricated components and the cast-in-place structure into a unified whole that shares the load. When the staircase is subjected to vertical loads or horizontal seismic forces, the load can be evenly transferred to the second connection mechanism through multiple distributed first connection mechanisms, and finally borne by the cast-in-place shear wall. This effectively avoids the risk of staircase collisions or detachment that may occur in traditional sliding connections, ensuring the reliability of the connection nodes and the overall safety of the structure. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a structural schematic diagram of the prefabricated staircase provided by the present invention; Figure 2 for Figure 1 A schematic diagram of the BB cross-sectional structure in the example; Figure 3 for Figure 2 An enlarged structural diagram of part A in the example; Figure 4 This is a structural schematic diagram illustrating the filling state of the filling gap in this invention. Figure 5 for Figure 1 A schematic diagram of the CC cross-sectional structure in the example; Figure 6 This is a flowchart illustrating a construction method exemplified by the present invention.

[0019] Figure label: 100. Ladder body; 110. Mounting groove; 120. Embedded hole; 200. First connecting mechanism; 300. Second connecting mechanism; 210. Angle steel; 220. First side plate; 230. Second side plate; 240. Embedded component; 250. Filler; 241. Adhesive block; 242. Embedded screw; 310. Connecting screw; 320. Anchor plate; 130. Filling gap; 400. Fireproof rock wool board; 500. PE rod; 600. Weather-resistant structural adhesive layer; 700. Shear wall.

[0020] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0022] It should be noted that if the embodiments of the present invention involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a specific posture. If the specific posture changes, the directional indicators will also change accordingly.

[0023] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the use of "and / or" or "and / or" throughout the text includes three parallel solutions. For example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0024] This invention proposes a prefabricated staircase and its construction method.

[0025] Please see Figures 1 to 6 For ease of understanding, this type of prefabricated staircase includes: The ladder body 100 has multiple mounting grooves 110 formed on its ladder surface. All mounting grooves 110 are distributed at intervals along the length extension direction of the ladder body 100 on the same side of the ladder body 100. Each mounting groove 110 has a pre-embedded hole 120 formed at the bottom of its groove. Multiple first connecting mechanisms 200 are provided, with the number of first connecting mechanisms 200 matching the number of mounting slots 110 and installed in a one-to-one correspondence. Each first connecting mechanism 200 is anchored to the ladder body 100 through a corresponding pre-embedded hole 120. The first connecting mechanism 200 extends out of the ladder body 100 along its width and forms a welding position; and... Multiple second connecting mechanisms 300 are provided, the number of which is the same as that of the first connecting mechanism 200. The second connecting mechanisms 300 are welded to the corresponding welding positions. The second connecting mechanisms 300 are embedded in the external cast-in-place shear wall 700 located on one side of the ladder body 100, so that the ladder body 100 and the external cast-in-place shear wall 700 are connected as one unit.

[0026] Specifically, the present invention provides a prefabricated staircase. The prefabricated staircase includes a staircase body 100, a plurality of first connecting mechanisms 200, and a plurality of second connecting mechanisms 300. The staircase body 100 is a prefabricated stepped concrete component with a step surface for people to step on. On the step surface of the staircase body 100, a plurality of mounting grooves 110 are formed at intervals along the length extension direction of the staircase body 100 (i.e., the direction of the staircase). The phrase "on the same side of the staircase body 100" means that all mounting grooves 110 are located at the left edge or right edge of the staircase body 100, rather than being dispersed on both sides, thus forming a single-sided centralized connection structure. Each mounting groove 110 has a pre-embedded hole 120 at its bottom, which is used to accommodate and anchor subsequent connecting components.

[0027] For each mounting slot 110, an independent first connecting mechanism 200 is provided. The lower part of the first connecting mechanism 200 is housed within the mounting slot 110, and an anchoring section extends from its bottom. This anchoring section passes through the pre-embedded hole 120 and penetrates into the concrete interior of the ladder body 100, achieving a fixed connection with the ladder body 100 through anchoring media such as high-strength grout or structural adhesive. This connection method allows the first connecting mechanism 200 and the ladder body 100 to be solidified into an integral load-bearing unit during the prefabrication stage. After anchoring, the main body of the first connecting mechanism 200 is not completely hidden within the ladder body 100, but extends outward along the width direction of the ladder body 100 (i.e., the horizontal direction perpendicular to the staircase direction), protruding from the side edge of the ladder body 100. The lower edge or end face of this protruding part constitutes the preset welding position.

[0028] Meanwhile, multiple second connecting mechanisms 300 are pre-embedded in the external cast-in-place shear wall 700 that needs to be connected to the precast staircase. The number of second connecting mechanisms 300 is consistent with the number of first connecting mechanisms 200, and their positions correspond one-to-one. The embedded end of the second connecting mechanism 300 is anchored in the steel reinforcement skeleton of the cast-in-place shear wall 700 and forms an integral part with it after the concrete of the shear wall 700 is poured; the other end of the second connecting mechanism 300 is exposed on the side wall surface of the shear wall 700 for receiving welding operations.

[0029] During assembly at the construction site, the prefabricated staircase is first hoisted to the designated installation position. At this point, the first connecting mechanism 200 on one side of the staircase body 100 naturally aligns with the second connecting mechanism 300 on the side wall of the external cast-in-place shear wall 700. Construction workers no longer need to operate on the narrow end faces of the stair slabs; instead, they can weld the extended welding positions in the open space above the steps of the staircase body 100. Through welding, the first connecting mechanism 200 and the second connecting mechanism 300 are fixed together at the gap between the staircase body 100 and the shear wall 700. Because multiple connecting nodes are spaced apart along the length of the staircase body 100, welding shrinkage stress is dispersed, and the open welding work space greatly facilitates operation and ensures the quality of the weld formation.

[0030] In this embodiment, since the first connecting mechanism 200 is anchored in the mounting groove 110 on the ladder surface and extends to the side to form a welding position, the welding operation surface is shifted from the narrow end face of the ladder plate in the traditional process to the open side area of ​​the ladder plate. This change in spatial position allows the welder to perform overhead or flat welding in a comfortable posture, effectively avoiding quality defects such as incomplete weld fusion and slag inclusion caused by limited operating space, and ensuring the directness and stability of the force transmission path. Secondly, the structural layout of the mounting grooves 110 distributed at intervals on the same side along the length of the ladder body 100 means that only one side needs to be aligned during hoisting and positioning. Compared with the two-end insertion of reinforcing bars to align holes or the leveling of pre-embedded parts on both sides, the difficulty of installation and positioning and the labor intensity of repeated manual adjustments are significantly reduced, greatly improving construction efficiency. Finally, the second connecting mechanism 300 embedded in the shear wall 700 and the first connecting mechanism 200 on the ladder body 100 are rigidly connected by welding, integrating the originally separate prefabricated components and the cast-in-place structure into a whole that shares the load. When the ladder body 100 is subjected to vertical loads or horizontal seismic forces, the load can be evenly transferred to the second connection mechanism 300 through multiple distributed first connection mechanisms 200, and finally borne by the cast-in-place shear wall 700. This effectively avoids the risk of ladder segments colliding or detaching that may occur in traditional sliding connections, and ensures the reliability of the connection nodes and the overall safety of the structure.

[0031] In one embodiment, the first connecting mechanism 200 includes: Angle steel 210 is installed in the mounting groove 110. Angle steel 210 has a first side plate 220 and a second side plate 230 that are connected to each other and integrally formed. The first side plate 220 extends outward from the ladder body 100 along the width direction and forms a welding position. The second side plate 230 is provided with a through hole that runs vertically through the ladder body 100. The through hole corresponds to the position of the pre-embedded hole 120. An embedded component 240 is provided, which vertically passes through the through hole and extends into the corresponding embedded hole 120 to anchor the angle steel 210 to the ladder body 100; and, Filler 250 is filled into mounting groove 110 to pre-embed angle steel 210 in mounting groove 110.

[0032] Specifically, the ladder body 100 has multiple mounting grooves 110 formed on its surface, and each mounting groove 110 has a pre-embedded hole 120 at its bottom. An angle steel 210 is provided for each mounting groove 110. The angle steel 210 is installed inside the corresponding mounting groove 110. The angle steel 210 has a first side plate 220 and a second side plate 230 that are interconnected and integrally formed. The first side plate 220 and the second side plate 230 are typically arranged at an angle, for example, at a right angle. The first side plate 220 extends outward along the width direction of the ladder body 100, that is, it extends towards the side away from the center of the ladder body 100, and finally protrudes beyond the side edge of the ladder body 100. The second side plate 230 is fitted to the bottom of the mounting groove 110, and a through hole is formed on the second side plate 230 that penetrates the plate vertically (i.e., along the thickness direction of the ladder body 100). The location of the through hole corresponds vertically to and overlaps with the location of the pre-embedded hole 120 at the bottom of the mounting groove 110.

[0033] The pre-embedded component 240 passes vertically from top to bottom through the through hole on the second side plate 230 and continues downward into the pre-embedded hole 120 of the ladder body 100. A portion of the pre-embedded component 240 is housed within the channel formed by the through hole and the pre-embedded hole 120, and is firmly connected to the concrete substrate of the ladder body 100 through an anchoring medium such as grout or structural adhesive. Through this connection structure, the pre-embedded component 240 presses the second side plate 230 of the angle steel 210 tightly against the bottom surface of the mounting groove 110, thereby firmly anchoring the entire angle steel 210 component to the ladder body 100, making the angle steel 210 and the ladder body 100 a single load-bearing component.

[0034] After the angle steel 210 is positioned and anchored, the filler 250 is filled into the remaining space of the mounting groove 110. The filler 250 can be a non-shrink grout, polymer mortar, or other suitable filler material with the same or similar concrete strength grade as the ladder body 100. The filler 250 completely covers and embeds the second side plate 230 of the angle steel 210 and the upper end of the embedded component 240 within the mounting groove 110, so that the surface of the mounting groove 110 is restored to flatness and flush with the surrounding ladder surface. Thus, except for the portion of the first side plate 220 that extends outward to form a welding surface, the second side plate 230 and the embedded component 240 of the angle steel 210 are reliably embedded inside the ladder body 100.

[0035] In this embodiment, angle steel 210 is used as the main load-bearing component of the first connecting mechanism 200, which has high bending stiffness and load-bearing capacity. The first side plate 220 extends outward to form a welding position, providing a wide operating space for on-site welding and avoiding the unfavorable working conditions of overhead or vertical welding on narrow end faces. The second side plate 230 fits into the bottom of the mounting groove 110 and is vertically anchored through the embedded component 240, so that the vertical and horizontal loads borne by the ladder body 100 can be effectively transferred to the angle steel 210 through the bearing surface of the second side plate 230 and the shear surface with the embedded component 240, and then transferred to the second connecting mechanism 300 through the weld of the first side plate 220 of the angle steel 210. Compared with the connection method that relies solely on a single steel bar tie, the force transmission path of this structure is more clear and reliable.

[0036] Secondly, the connection method of the pre-embedded component 240 passing vertically through the through hole and anchoring to the pre-embedded hole 120 can be completed during the factory prefabrication stage. Production personnel only need to align the through hole of the second side plate 230 of the angle steel 210 with the pre-embedded hole 120 on the ladder body 100, insert the pre-embedded component 240, and perform grouting or tightening to achieve accurate positioning. This structure avoids the complicated operations of threading reinforcement or aligning holes in narrow spaces during on-site installation, significantly reducing the positioning difficulty when hoisting and positioning the ladder body 100, and improving construction efficiency.

[0037] Finally, the installation of the filler 250 not only restores the flatness of the stair surface, ensuring the normal function and appearance of the staircase, but more importantly, the filler 250 completely covers the second side plate 230 of the angle steel 210 and the embedded component 240, isolating them from the external environment and effectively preventing the risk of corrosion of metal components during long-term use, thus improving the durability of the connection joint. Simultaneously, after hardening, the filler 250 forms a fixed embedding effect with the angle steel 210, further enhancing the pull-out and torsional resistance of the angle steel 210 within the mounting groove 110, ensuring the stability of the connection structure under long-term cyclic loads.

[0038] In one embodiment, the embedded component 240 includes: Adhesive block 241, adhesive block 241 fills the pre-embedded hole 120; and, An embedded screw 242 is inserted into the through hole and one end is anchored in the adhesive block 241 to anchor the angle steel 210 to the ladder body 100.

[0039] Specifically, the embedded component 240 includes an adhesive block 241 and an embedded screw 242. An installation groove 110 is formed on the ladder surface of the ladder body 100, and an embedded hole 120 is formed at the bottom of the groove. The second side plate 230 of the angle steel 210 is fitted to the bottom of the installation groove 110, and a vertically penetrating through hole is formed on the second side plate 230, which corresponds vertically to the embedded hole 120 below. Based on this, the adhesive block 241 is pre-filled into the interior of the embedded hole 120. The adhesive block 241 is an anchoring matrix formed by the injection and hardening of a curable material with fluidity and adhesiveness into the embedded hole 120, forming a tight bond between it and the concrete wall of the embedded hole 120.

[0040] The embedded screw 242 is a slender rod-shaped metal component with threads machined on its surface. The embedded screw 242 is vertically inserted from top to bottom into the through hole of the second side plate 230 of the angle steel 210. The lower end of the embedded screw 242 extends into the embedded hole 120 and is completely covered and fixed therein by the adhesive block 241. The upper end of the embedded screw 242 passes through the through hole and protrudes from the upper surface of the second side plate 230 of the angle steel 210. After the adhesive block 241 reaches the predetermined curing strength, the lower end of the embedded screw 242 is reliably anchored within the embedded hole 120 of the ladder body 100. At this point, the second side plate 230 of the angle steel 210 can be tightly pressed and fixed to the bottom surface of the mounting groove 110 by screwing a nut into the upper end of the embedded screw 242 and tightening it. With this structure, the angle steel 210 is firmly connected to the ladder body 100 as an integral load-bearing component through the anchoring effect of the pre-embedded screw 242 and the adhesive block 241.

[0041] After the angle steel 210 is positioned and anchored, the remaining space of the mounting groove 110 is filled by the filler 250, which covers the second side plate 230 of the angle steel 210 and the upper end of the pre-embedded screw 242, so that the ladder surface is restored to flatness.

[0042] In this embodiment, the anchoring method using a combination of adhesive block 241 and pre-embedded screw 242 provides a clear and reliable force transmission path. When the ladder body 100 bears external loads, the pull-out force or shear force on the angle steel 210 is transmitted to the adhesive block 241 through the pre-embedded screw 242. Then, the adhesive block 241, through the bonding stress and mechanical interlocking force between itself and the concrete wall of the pre-embedded hole 120, evenly diffuses and transmits the load to the concrete matrix of the ladder body 100. Compared to the connection method that relies solely on inserting a single plain round steel bar directly into the pre-embedded hole 120 for grouting, the threaded structure on the surface of the pre-embedded screw 242 can form a tighter spiral engagement with the cement block 241, significantly enhancing the pull-out bearing capacity of the pre-embedded screw 242 in the cement block 241. This avoids the risk of slippage or loosening of the pre-embedded screw 242 under long-term reciprocating loads, thereby ensuring the long-term stability of the connection node between the ladder body 100 and the external cast-in-place shear wall 700.

[0043] Secondly, the prefabrication plant offers significant convenience in production operations. During the production stage of the prefabricated ladder body 100, the pre-embedded holes 120 can be cleaned and the bottom temporarily sealed. Then, a fluid adhesive material is injected into the pre-embedded holes 120. Before the adhesive material cures, the pre-embedded bolts 242 are inserted from top to bottom through the through holes of the second side plate 230 of the angle steel 210 and into the uncured adhesive material. After adjusting the verticality and position, they are left to cure. Once the adhesive material cures and forms an adhesive block 241, the pre-embedded bolts 242 become integrated with the ladder body 100, and the angle steel 210 is initially positioned. This construction process avoids complex on-site drilling or alignment work in the narrow installation slot 110. Production personnel only need to simply insert the bolts and wait for curing to complete the high-precision anchoring of the angle steel 210. This process is simple to operate, effectively shortening the production cycle of prefabricated components and improving factory production efficiency.

[0044] In one embodiment, the adhesive block 241 is made of cement mortar or structural adhesive.

[0045] Specifically, the pre-embedded hole 120 is opened at the bottom of the mounting groove 110 of the ladder body 100, and the pre-embedded bolt 242 passes through the through hole of the second side plate 230 of the angle steel 210, with its lower end anchored in the adhesive block 241 filled in the pre-embedded hole 120. The adhesive block 241 serves as an intermediate force transmission medium connecting the pre-embedded bolt 242 and the concrete matrix of the ladder body 100, and its material properties directly affect the reliability and durability of the anchoring connection.

[0046] In this embodiment, the material of the binder block 241 can be cement mortar. Cement mortar is a mixture made by mixing cement, fine aggregate sand, and water in a certain proportion. During the production process of the precast ladder body 100, the mixed cement mortar is injected into the pre-embedded hole 120, and then the lower end of the pre-embedded screw 242 is inserted into the cement mortar that has not yet solidified. After being vibrated and compacted, it is left to cure. During the hydration and hardening process, the cement mortar forms a good bond with the concrete matrix of the pre-embedded hole 120, and at the same time tightly wraps the lower end of the pre-embedded screw 242. The hardened cement mortar has similar mechanical properties and coefficient of thermal expansion to the concrete of the ladder body 100, and can deform in coordination with the ladder body 100 under temperature changes or loads, avoiding additional stress or cracking at the interface due to excessive differences in material properties. In addition, as a traditional building material, cement mortar has the advantages of wide availability, low cost, and mature construction technology, making it suitable for large-scale mass production in precast component factories.

[0047] In another embodiment, the adhesive block 241 can be made of structural adhesive. Structural adhesive is a polymeric bonding material with synthetic resin as its main component, typically a two-component or multi-component system. It is mixed uniformly in proportion at the construction site or prefabrication plant and then injected into the pre-embedded holes 120. Before curing, the structural adhesive has good fluidity, allowing it to fully penetrate the tiny pores in the hole walls of the pre-embedded holes 120 and the threaded grooves on the surface of the pre-embedded screws 242, forming a high-strength bonding interface after curing. Compared to cement mortar, structural adhesive has higher bonding strength and faster curing speed, achieving the predetermined anchoring bearing capacity in a shorter time, thereby shortening the curing cycle of prefabricated components in the factory and improving the turnover efficiency of the production platform. Simultaneously, the structural adhesive has good toughness and can absorb a certain amount of impact energy, helping to alleviate stress concentration at connection nodes under dynamic loads such as earthquakes.

[0048] In this embodiment, the material of the binder block 241 can be flexibly selected according to different engineering needs and production conditions, enhancing the applicability of this precast staircase connection structure. When the production pace of the prefabrication plant is relatively slow and material cost control is strict, cement mortar can be preferred as the binder block 241 material to balance economy and anchoring reliability. When the prefabrication plant needs to demold quickly, accelerate the turnover of components, or when the connection node bears high fatigue loads and has higher requirements for vibration resistance, structural adhesive can be selected as the binder block 241 material to fully utilize its early strength and high bonding technical advantages. Secondly, both cement mortar and structural adhesive can form a dense filling in the pre-embedded hole 120, firmly bonding the pre-embedded screw 242 to the concrete of the ladder body 100. This ensures that the load transfer path from the first side plate 220 of the angle steel 210 through the second side plate 230, the pre-embedded screw 242, and the adhesive block 241 to the ladder body 100 is continuous and effective. This avoids the problem of loose connection caused by insufficient filling or strength of the anchoring material, thus ensuring the long-term safety of the connection structure between the precast staircase and the cast-in-place shear wall 700.

[0049] In one embodiment, the filler 250 is made of cement mortar.

[0050] Specifically, the angle steel 210 is installed in the mounting groove 110 on the ladder surface of the ladder body 100, and its second side plate 230 is anchored in the pre-embedded hole 120 at the bottom of the mounting groove 110 by the pre-embedded component 240. After the angle steel 210 is positioned and anchored, a cavity remains in the mounting groove 110 in addition to the space occupied by the angle steel 210 and the pre-embedded component 240. If this cavity is not treated, it will cause a depression to form on the ladder surface, affecting the normal use function and appearance integrity of the staircase.

[0051] Therefore, in this embodiment, cement mortar is used as filler 250 to fill the remaining space of the installation groove 110. The cement mortar is made by mixing cement, fine aggregate sand, and water in an appropriate proportion, and has good fluidity and plasticity. During the factory production stage of the prefabricated ladder body 100, after the angle steel 210 is anchored in place by the embedded component 240, the mixed cement mortar is poured or scraped into the cavity of the installation groove 110. Under its own weight or slight vibration, the cement mortar can fully fill all corners of the installation groove 110, completely covering the second side plate 230 of the angle steel 210 and the upper end of the embedded screw 242. After curing and hardening, the cement mortar forms a tight bond with the concrete wall of the installation groove 110 and the surface of the angle steel 210, restoring the surface of the installation groove 110 area to a state flush with the surrounding ladder surface.

[0052] In this embodiment, cement mortar is used as the filler 250, and its material composition is highly homologous to the concrete matrix of the ladder body 100. Both use cement as the main cementing material, and their coefficients of thermal expansion and moduli of elasticity are similar. Under temperature changes or loads, the filler 250 and the ladder body 100 can deform in coordination, and excessive shear stress or tensile stress will not be generated at the bonding interface due to differences in material properties, thereby effectively avoiding durability damage such as separation or cracking between the filler 250 and the ladder body 100. Secondly, after the cement mortar hardens, it has a certain strength. When filled into the installation groove 110, it not only restores the geometric flatness of the ladder surface, but also provides lateral support and constraint for the second side plate 230 of the angle steel 210 and the pre-embedded screw 242 embedded therein. When the first side plate 220 of the angle steel 210 bears the load transmitted from the welding position, the filler 250 can help resist the torsional or warping deformation that may occur in the angle steel 210 within the mounting groove 110, enhancing the embedding rigidity of the first connecting mechanism 200 within the ladder body 100. Furthermore, the cement mortar isolates the metal surfaces of the angle steel 210 and the embedded bolt 242 from external air and moisture, acting as a physical barrier to delay or prevent corrosion of the metal components during long-term use, thereby ensuring the durability and service life of the connection joint. Finally, as a conventional building material, cement mortar has readily available raw materials, simple and mature mixing and construction processes, and can be filled in a prefabrication plant without the need for additional specialized equipment, offering significant economic benefits and construction convenience.

[0053] In one embodiment, the second connecting mechanism 300 includes: Multiple connecting bolts 310 are used to connect to the reinforcing cage of the external cast-in-place shear wall 700, and all connecting bolts 310 extend outward along the thickness direction of the external cast-in-place shear wall 700 to form an installation area on one side of the external cast-in-place shear wall 700; and, Anchor plate 320 is connected to connecting screw 310 and located within the installation area. The side of anchor plate 320 facing angle steel 210 is used for welding with the welding position of angle steel 210.

[0054] Specifically, the second connecting mechanism 300 is pre-embedded in the external cast-in-place shear wall 700 located on one side of the ladder body 100. Multiple connecting bolts 310 are pre-arranged during the reinforcement cage binding stage of the external cast-in-place shear wall 700. Each connecting bolt 310 is arranged horizontally, with its extension direction consistent with the thickness direction of the external cast-in-place shear wall 700. One end of the connecting bolt 310 facing the ladder body 100 extends outward, while the other end facing away from the ladder body 100 penetrates into the shear wall 700 and is fixedly connected to the reinforcement cage of the shear wall 700 by binding or welding. After the connecting bolt 310 is connected to the reinforcement cage, it is embedded together during the subsequent concrete pouring process, thus making the connecting bolt 310 an extension of the internal load-bearing skeleton of the cast-in-place shear wall 700. All connecting bolts 310 are arranged in parallel along the thickness direction of the shear wall 700, and their protruding ends together enclose a planar area on the side wall surface of the shear wall 700 facing the ladder body 100. This area is the installation area for subsequent component installation.

[0055] Anchor plate 320 is a plate-shaped metal component whose planar dimensions match the dimensions of the installation area. Anchor plate 320 is installed within the installation area before or after the concrete pouring of the shear wall 700 (through pre-embedding or post-installation). Multiple through holes are formed on the surface of anchor plate 320, the number and location of which correspond to the arrangement of connecting bolts 310. The protruding end of the connecting bolt 310 passes through the corresponding through hole on anchor plate 320, and anchor plate 320 is tightly fixed to the side wall surface of the external cast-in-place shear wall 700 by screwing a nut into the end of the connecting bolt 310 and tightening it. Thus, anchor plate 320 forms a strong mechanical connection with cast-in-place shear wall 700 through connecting bolts 310. The side of anchor plate 320 facing angle steel 210 is the welding mating surface; this side surface is flat and used for butt welding to the welding position on the first side plate 220 of angle steel 210 on the construction site.

[0056] When assembling and connecting the precast staircase and the cast-in-place shear wall 700 at the construction site, as described in the aforementioned embodiment, the staircase body 100 is hoisted to a predetermined position, and the welding position of the first side plate 220 of the angle steel 210 naturally approaches and aligns with the welding mating surface of the anchor plate 320. In an open working space, construction workers weld along the joint between the first side plate 220 of the angle steel 210 and the anchor plate 320, fixing the two together as one. After welding, the first connecting mechanism 200 on the staircase body 100 and the second connecting mechanism 300 on the shear wall 700 form a rigid connection node through the weld.

[0057] In this embodiment, the second connecting mechanism 300 adopts a structure combining multiple connecting bolts 310 and anchor plates 320, which provides a clear and reliable force transmission path for the connecting nodes on one side of the shear wall 700. When the ladder body 100 bears a load, the load is transmitted to the weld via the first side plate 220 of the angle steel 210, and then from the weld to the anchor plate 320. As a plate-shaped member with high rigidity, the anchor plate 320 can evenly diffuse the force concentrated on the weld to the multiple connecting bolts 310 connected to it. The connecting bolts 310, as axially tensioned or sheared members, further transmit the load to the concrete matrix of the cast-in-place shear wall 700 and its internal reinforcing cage. This multi-stage force transmission path of "ladder body 100 → angle steel 210 → weld → anchor plate 320 → connecting bolts 310 → shear wall 700" has clear force layers, avoids excessive stress concentration at a single weak section, and significantly improves the load-bearing capacity and fatigue resistance of the connecting nodes.

[0058] The anchor plate 320 provides a relatively spacious welding mating surface. Compared to directly welding the first connecting mechanism 200 to the ends of the discrete connecting screws 310, welding with the anchor plate 320 offers a wider operational tolerance. Even if the ladder body 100 has a certain positional deviation during hoisting and positioning, as long as the welding position of the first side plate 220 of the angle steel 210 can overlap the surface of the anchor plate 320, an effective welded connection can be formed without the need for precise cutting or shim adjustment on site. This structural feature greatly reduces the stringent requirements for positioning accuracy during on-site installation, reduces the time and manpower spent by construction personnel repeatedly adjusting the position of components, and thus improves the efficiency of prefabricated construction.

[0059] The connecting bolt 310 is fixed to the reinforcing cage before the shear wall 700 is poured, making the second connecting mechanism 300 an integral part of the cast-in-place shear wall 700, rather than an independent component added later. This integrated structure ensures the coordinated working performance between the connecting node and the main structure. Under horizontal cyclic loads such as earthquakes, the connecting bolt 310 can participate in the stress-bearing process together with the reinforcing cage inside the shear wall 700, avoiding node failure due to anchorage failure and ensuring the overall safety of the structure.

[0060] In one embodiment, a filling gap 130 is formed between the ladder body 100 and the external cast-in-place shear wall 700, and a gap sealing component is filled in the filling gap 130.

[0061] Specifically, in this assembled state, the side edge of the ladder body 100 is not completely fitted with the side wall surface of the external cast-in-place shear wall 700, but there is a certain space distance. This space distance is naturally formed to accommodate the extension section of the first connecting mechanism 200, the thickness of the anchor plate 320 of the second connecting mechanism 300, and the operating space required for welding operations. At the same time, considering the manufacturing tolerance of prefabricated components and the adjustment allowance during on-site installation, a narrow gap extending along the length of the ladder body 100 must be left between the side end face of the ladder body 100 and the side wall surface of the cast-in-place shear wall 700. This gap is the filling gap 130.

[0062] The gap sealing component is filled and disposed within the filling gap 130. The gap sealing component can be a plastic and adhesive sealing material or a pre-formed filling strip, and its function is to seal and fill the filling gap 130.

[0063] In this embodiment, the gap-sealing component meets the requirements of building fire protection codes. In a building fire scenario, the stairwell, as a vertical safety passage for personnel evacuation, must have an enclosure structure capable of preventing the spread of flames and high-temperature smoke. If the gap 130 between the stairwell body 100 and the external cast-in-place shear wall 700 is not sealed, it will become a channel for the spread of smoke and fire during a fire, weakening the fire-resistant separation effectiveness of the stairwell. The gap-sealing component, filling this gap, can effectively block the path of flame propagation and the path of smoke flow, reliably separating the stairwell from adjacent areas and ensuring the safety performance of the evacuation route under fire conditions.

[0064] The gap-sealing component meets the requirements for building waterproofing and seepage prevention. During daily use of the building, water may flow into the stairwell due to cleaning or accidental water accumulation. If the filling gap 130 is open, water may flow into the connection node area along the side of the stair body 100. Long-term water accumulation will accelerate the corrosion of the metal components of the first connection mechanism 200 and the second connection mechanism 300, reducing the durability and service life of the connection node. After the gap-sealing component seals the filling gap 130, it can effectively prevent water from seeping into the connection node, maintain a dry environment in the node area, thereby slowing down the corrosion process of the metal components and ensuring the long-term working performance of the connection node. It also improves the acoustic performance and visual effect of the stairwell. The presence of the filling gap 130 creates a through gap between the stair body 100 and the shear wall 700, which not only affects the visual integrity of the stairwell but may also become a path for sound transmission between floors. After the gap sealing components are filled, a continuous and smooth transition is formed between the stair surface and the 700mm side wall of the shear wall, which improves the overall visual effect of the stairwell. At the same time, the sealing material has a certain sound insulation performance, which can block the sound transmission along the gap to a certain extent and improve the sound environment quality of the stairwell.

[0065] In one embodiment, the gap sealing assembly includes a fireproof rock wool board 400, two PE rods 500 and two layers of weather-resistant structural adhesive 600. The fireproof rock wool board 400 is filled in the filling gap 130, and a PE rod 500 is filled on each side of the fireproof rock wool board 400 in the height direction. On the side of each PE rod 500 away from the fireproof rock wool board 400, a layer of weather-resistant structural adhesive 600 is filled.

[0066] Specifically, fireproof rock wool boards 400 are filled within the filling gaps 130. The fireproof rock wool boards 400 are inorganic fiber boards made from natural minerals such as basalt, which are melted at high temperatures and then fiberized. They possess excellent non-combustibility and high-temperature stability. The fireproof rock wool boards 400 are continuously laid along the length of the filling gaps 130, and their width dimension matches the depth of the filling gaps 130, allowing the fireproof rock wool boards 400 to be tightly embedded within the gaps. The installation of the fireproof rock wool boards 400 forms an effective horizontal fireproof partition layer between the side wall of the ladder body 100 and the side wall of the cast-in-place shear wall 700.

[0067] On both sides of the fireproof rock wool board 400 along its height direction, namely above and below the fireproof rock wool board 400, one PE rod 500 is respectively installed. The PE rod 500 is a cylindrical or near-cylindrical flexible strip material made of polyethylene, with a closed-cell foam structure inside, possessing good compression resilience and waterproof sealing performance. The upper PE rod 500 is pressed into the gap between the upper surface of the fireproof rock wool board 400 and the upper sidewall of the filling gap 130, and the lower PE rod 500 is pressed into the gap between the lower surface of the fireproof rock wool board 400 and the lower sidewall of the filling gap 130. The two PE rods 500 are arranged along the length of the filling gap 130, filling the remaining space between the upper and lower ends of the fireproof rock wool board 400 and the gap wall.

[0068] On the side of each PE rod 500 away from the fireproof rock wool board 400, a layer of weather-resistant structural adhesive 600 is filled. Specifically, a layer of weather-resistant structural adhesive 600 is filled between the upper surface of the upper PE rod 500 and the upper sidewall of the filling gap 130; a layer of weather-resistant structural adhesive 600 is also filled between the lower surface of the lower PE rod 500 and the lower sidewall of the filling gap 130. The weather-resistant structural adhesive 600 is continuously applied along the length of the filling gap 130, and its outer surface is smoothed and connected to the edge of the ladder surface of the ladder body 100 and the sidewall surface of the cast-in-place shear wall 700.

[0069] In this embodiment, the fireproof rock wool board 400 serves as the core fireproof layer of the gap sealing component. Its material is a Class A non-combustible material with a high melting temperature, and it does not produce toxic fumes under high temperatures during a fire, while maintaining structural integrity for an extended period. When a fire occurs in the stairwell, the fireproof rock wool board 400 effectively prevents flames and high-temperature airflow from spreading to adjacent floors or fire compartments through the filling gap 130, buying valuable time for evacuation and fire rescue, and ensuring that the connection area between the precast staircase and the external cast-in-place shear wall 700 meets the fire resistance limit requirements of the building fire protection code. The PE rod 500, with its closed-cell foam structure and compression-rebound characteristics, can form an elastic and dense fill within the filling gap 130. When the staircase body 100 or the cast-in-place shear wall 700 experiences slight relative displacement due to temperature changes, concrete shrinkage and creep, or accidental loads, the PE rod 500 can adaptively compress or rebound, maintaining a tight fit with the gap wall and effectively preventing water from seeping deep into the connection joint along the gap wall. The weather-resistant structural adhesive layer 600 is applied to the outside of the PE rod 500 and bonded and cured to the surface of the staircase and shear wall 700, forming a continuous surface sealing layer. This surface sealing layer not only further blocks the intrusion of moisture and humid air, but also resists the erosion of sunlight and atmospheric environment, preventing the PE rod 500 from aging and becoming brittle due to long-term exposure, thus ensuring the long-term stability of the waterproof sealing function. The fireproof rock wool board 400 is located deep in the filling gap 130 and undertakes the main fireproof and heat insulation tasks; the PE rod 500 and the weather-resistant structural adhesive layer 600 are located in the shallow part and on the surface of the filling gap 130 and undertake the main waterproof sealing and weather protection tasks. Each layer of material performs its own function without interfering with each other, and the presence of the PE rod 500 provides a certain lateral restraint for the fireproof rock wool board 400, preventing it from loosening or falling off during use.

[0070] Based on the same technical concept, in a second aspect, the present invention also proposes a construction method for a prefabricated staircase, characterized in that it is used for constructing the prefabricated staircase described in the first aspect; The construction method includes the following steps: S100, Provide an external load-bearing beam and an external cast-in-place shear wall that have reached a preset strength; wherein, the second connecting mechanism is pre-embedded in the external cast-in-place shear wall.

[0071] During the main structure construction phase, the reinforcement binding, formwork erection, and concrete pouring of the external load-bearing beams and external cast-in-place shear walls were carried out first, according to the design drawings. The external load-bearing beams provide vertical support for the lower end of the stair treads, while the external cast-in-place shear walls provide the attachment base for the lateral connections of the staircases. During the reinforcement cage binding stage of the external cast-in-place shear walls, the connecting bolts of the second connecting mechanism were bound or welded to the reinforcement cage at predetermined intervals and positions. The connecting bolts were arranged horizontally along the thickness direction of the shear wall, with their protruding ends facing the side where the precast staircase will be installed. Subsequently, the shear wall side formwork was erected and concrete was poured. After the concrete hardened and reached the preset strength, the side formwork was removed, exposing the protruding ends of the connecting bolts on the surface of the shear wall sidewall, thus enclosing an installation area on that sidewall surface. Subsequently, the anchor plate is installed in place by connecting the exposed end of the bolt, and the anchor plate is fixed tightly to the side wall surface of the shear wall by screwing in the nut and tightening it, thus completing the pre-embedded setting of the second connection mechanism on one side of the external cast-in-place shear wall.

[0072] S200. The ladder body is hoisted and installed on the external load-bearing beam, so that the side of the ladder body with the installation groove is opposite to the external cast-in-place shear wall, and the filling gap is formed between the ladder body and the external cast-in-place shear wall.

[0073] The ladder body is prefabricated in the prefabrication factory. Multiple installation grooves are spaced along the length of the ladder surface, and each groove has a pre-embedded hole at its bottom. Before hoisting the ladder body, the angle steel and pre-embedded components in the first connecting mechanism can be pre-anchored in the factory, and the installation grooves can be filled and smoothed; alternatively, the ladder body can be installed on-site after it is in place. This embodiment describes the preferred method of pre-installation in the factory. At the construction site, a lifting device is used to hoist the ladder body to the top of the external load-bearing beam and lower it slowly. The lower end of the ladder body rests on the top support surface of the external load-bearing beam, with the side edge of the ladder body facing the side wall surface of the external cast-in-place shear wall. Construction workers adjust the planar position of the ladder body using pry bars or fine-tuning devices, ensuring that the side of the ladder body with the installation groove faces the shear wall, and that a gap extending along the length of the ladder body is left between the side end face of the ladder body and the side wall surface of the shear wall; this gap is the filling gap. The width of the filling gap is predetermined based on the extension length of the first connecting mechanism, the thickness of the anchor plate, and the space requirements for welding operations.

[0074] S300. Install the first connecting mechanism in each of the mounting slots.

[0075] If the first connecting mechanism has already been installed in the prefabrication plant, this step on-site involves inspecting and verifying the position of the pre-installed first connecting mechanism. If the first connecting mechanism is installed on-site, this step is as follows: Place the second side plate of the angle steel against the bottom of the installation groove, ensuring the through hole on the second side plate is vertically aligned with the pre-embedded hole at the bottom of the installation groove. Insert the pre-embedded screw through the through hole from top to bottom and into the pre-embedded hole. A binder material (such as cement mortar or structural adhesive) has been pre-injected into the pre-embedded hole, and the lower end of the pre-embedded screw is embedded in the uncured binder material. After the binder material cures and forms a binder block, the lower end of the pre-embedded screw is firmly anchored. At this point, screw a nut into the upper end of the pre-embedded screw and tighten it, pressing the second side plate of the angle steel firmly against the bottom of the installation groove. Then, use filler (such as cement mortar) to fill and smooth the remaining space in the installation groove. Whether pre-assembled in the factory or installed on-site, the first side plate of the angle steel extends outward from the side of the ladder body along the width direction, and the lower surface or end face of the protruding part constitutes the welding position.

[0076] S400, Weld each of the first connecting mechanisms to the corresponding second connecting mechanism.

[0077] After the ladder body is in place and the first connecting mechanism is installed, the welding position of the first side plate of the angle steel naturally overlaps or is close to the side of the anchor plate facing the angle steel. At this time, the construction workers are in an open space above the ladder steps, holding a welding torch to weld along the joint between the first side plate of the angle steel and the anchor plate. Welding can be done manually using electric arc welding or carbon dioxide gas shielded welding. During welding, welding is performed along the edge or end face of the first side plate of the angle steel to form continuous and full fillet welds or butt welds. Because the welding position is on the side of the ladder body rather than a narrow end face, the welder's operating posture is comfortable, the field of vision is wide, and the weld quality is easily guaranteed. After completing the welding connection of each pair of the first connecting mechanism and the second connecting mechanism, the ladder body is connected to the external cast-in-place shear wall as a whole through multiple rigid nodes distributed along the length direction.

[0078] S500. The filling gap is sealed to complete the construction of the prefabricated staircase.

[0079] After welding is completed and the weld quality inspection is passed, the gap between the staircase body and the external cast-in-place shear wall is sealed. First, weld slag, dust, and debris are cleaned from the gap. Then, fireproof rock wool boards are cut to a width matching the depth of the gap and embedded into it along its length. PE rods are embedded on both sides (top and bottom) of the fireproof rock wool boards along their height, ensuring they are properly compressed and tightly fitted to the upper and lower walls of the gap. Finally, a weather-resistant structural adhesive layer is applied to the outer surface of each PE rod, and a scraper is used to smooth the adhesive, ensuring a smooth transition with the staircase edge and the shear wall sidewall. Once the weather-resistant structural adhesive layer has cured, the gap sealing assembly is complete.

[0080] At this point, all construction work on the prefabricated staircase is complete.

[0081] In this embodiment, the external cast-in-place shear wall is first poured, and the second connecting mechanism is pre-embedded within it, so that the shear wall sidewall is ready to support the precast staircase connection after demolding. When hoisting the staircase body, it only needs to be placed on the load-bearing beam and aligned with the single-sided connection position. Compared with the traditional process of simultaneously inserting reinforcing bars and aligning holes at both ends or simultaneously leveling the pre-embedded parts on both sides, the positioning difficulty is significantly reduced, the workload of repeated adjustments after hoisting is reduced, and the time occupied by lifting equipment during hoisting operations is shortened.

[0082] The welding of the first and second connecting mechanisms is scheduled after the ladder body is in place and before the gaps are filled and sealed, allowing for a spacious working area. The welding position is located on the first side plate of the angle steel extending from the side of the ladder body, rather than the narrow end face of the ladder section plate, allowing the welder to complete high-quality welds in a natural posture. This arrangement effectively avoids the drawbacks of traditional overhead or vertical welding processes, such as limited operating space and difficulty in controlling weld quality, ensuring the reliable stress performance of the connection joint.

[0083] The sealing of the gaps was scheduled after the welding work was completed, which not only did not affect the previous welding operations, but also allowed for timely functional sealing of the gaps after the joints were rigidly connected. The filling sequence of each layer of materials in the sealing construction was clear: fireproof rock wool boards were placed first to form a fireproof partition, PE rods were placed next to form an elastic seal, and the weather-resistant structural adhesive layer was applied last to form a surface seal and weather protection. The processes were closely connected, resulting in high construction efficiency.

[0084] In one embodiment, step S500 includes: S510. Fill the top opening of the installation groove with mortar material so that the ladder body is connected to the external cast-in-place shear wall as one unit.

[0085] Specifically, the construction workers fill the top opening area of ​​the installation groove. The mortar used can be cement mortar or polymer-modified mortar of the same strength grade as the concrete of the ladder body. During construction, the mortar is scraped or poured into the top opening of the installation groove, and its surface is smoothed with a trowel to make it flush with the surrounding ladder surface. After the mortar hardens, it forms a whole with the previously filled filler, completely covering and sealing the second side plate of the angle steel and the upper head of the pre-embedded bolt. Thus, the anchoring node of the first connecting mechanism on one side of the ladder body is completely embedded into the ladder body, and the ladder surface is restored to a complete and continuous usable surface. The completion of this step marks the end of the internal sealing work of the connecting node on the ladder body side, and the connection between the first connecting mechanism and the ladder body reaches a final stable state in terms of structure.

[0086] S520. Fireproof rock wool board is embedded in the filling gap.

[0087] Specifically, construction workers first clean the gaps in the filling area, using compressed air or a brush to remove any welding slag, dust, and loose particles that may be present. Then, pre-cut fireproof rock wool boards are embedded section by section into the gaps along their length. The cut width of the fireproof rock wool board should be slightly larger than the depth of the gap, ensuring proper compression contact with the concrete walls on both sides of the gap after embedding, guaranteeing the board is securely positioned and does not loosen. The fireproof rock wool boards should be laid continuously, with a tight, seamless joint between adjacent boards. The embedding depth of the fireproof rock wool boards should allow sufficient space between their outer surface and the side face of the staircase and the shear wall surface for subsequent installation of PE rods and weather-resistant sealant.

[0088] S530. Install a PE rod on each side of the fireproof rock wool board in the height direction.

[0089] Specifically, construction workers use PE rods, pressing one along the length of the cavity above the fireproof rock wool board and the other along the length of the cavity below. The PE rods are cylindrical, flexible strips with a diameter slightly larger than the corresponding cavity height. During installation, appropriate external force is used to press the PE rods into the cavities. Under pressure, the PE rods undergo elastic compression deformation, and their own rebound force ensures a tight fit between their outer circumference and the upper and lower walls of the cavity, as well as the edge surface of the fireproof rock wool board. The PE rods are arranged along the entire length of the filling gaps, and the joints of adjacent PE rods should be butt-jointed or beveled to ensure continuous sealing. The installation depth of the PE rods should allow for a groove space to be filled with weather-resistant sealant between their outer surface and the side end face of the ladder body and the side wall surface of the shear wall.

[0090] S540. Fill the side of each PE rod away from the fireproof rock wool board with weather-resistant sealant to complete the sealing of the filling gap.

[0091] Specifically, the construction workers use a caulking gun to continuously and evenly inject the weather-resistant sealant into the aforementioned grooves. During injection, the caulking gun should be moved at a uniform speed to ensure the sealant fully fills the grooves and effectively wets the PE rod surface and the concrete surfaces on both sides. After injection, a scraper is used to smooth the sealant surface along the length of the gap, creating a smooth transition with the edge of the staircase and the shear wall sidewalls, and excess sealant is removed. After scraping, the masking tape pre-attached to both sides of the gap is removed, resulting in a neat and aesthetically pleasing sealing surface. During the curing process, the weather-resistant sealant forms a strong bond with the concrete surfaces on both sides and the PE rod surface. Once fully cured, it forms the final surface sealing layer for filling the gap.

[0092] In this embodiment, the construction steps clearly define the filling sequence of each layer of materials: first, the top opening of the installation groove is filled to complete the internal sealing of the ladder body side node; then, fireproof rock wool boards are embedded, PE rods are installed, and weather-resistant sealant is applied to complete the external sealing of the filling gap. This "inside-out" operation sequence ensures that the internal anchoring structure and the external protective structure of the connection node are each a complete system and do not interfere with each other. The construction work surface is clear, the process is reasonably connected, and it is convenient for construction personnel to operate step by step and for quality inspection.

[0093] The sequential application of three layers of materials—fireproof rock wool board, PE rods, and weather-resistant sealant—achieved functional zoning for filling gaps. The fireproof rock wool board serves as the deep fireproof and heat-insulating layer, the PE rods as the middle elastic sealing layer, and the weather-resistant sealant as the surface waterproof and weather-resistant layer. Each layer was applied only after the previous layer was installed and inspected, ensuring that each layer was accurately positioned and of the intended thickness. This prevented functional failures caused by mixing multiple materials, guaranteeing the comprehensive performance of the gap-sealing component in terms of fire resistance, waterproofing, displacement adaptability, and durability.

[0094] The filling of the top opening of the installation groove with mortar is a conventional plastering operation, which is simple to operate; the cutting and embedding of fireproof rock wool boards is a manual operation, and the dimensional tolerance is easy to control; the extrusion embedding of PE rods utilizes the material's own elasticity and does not require precise measurement; the application and scraping of weather-resistant sealant is a conventional sealing operation, and the construction quality is easy to ensure. The entire sealing construction process does not require the use of special mechanical equipment, and ordinary construction personnel can master the operating essentials after brief training, which is conducive to its promotion and application on construction sites.

[0095] The above description is merely an exemplary embodiment of the present invention and does not limit the scope of the present invention. Any equivalent structural transformations made based on the technical concept of the present invention and the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the protection scope of the present invention.

Claims

1. A prefabricated staircase, characterized in that, include: The ladder body has multiple mounting grooves formed on its ladder surface. All the mounting grooves are distributed at intervals along the length extension direction of the ladder body on the same side of the ladder body, and a pre-embedded hole is formed at the bottom of each mounting groove. Multiple first connecting mechanisms are provided, the number of which corresponds to the number of mounting slots and are installed one-to-one. Each first connecting mechanism is anchored to the ladder body through a corresponding pre-embedded hole. The first connecting mechanism extends out of the ladder body along its width and forms a welding position. Multiple second connecting mechanisms are provided, the number of which is the same as that of the first connecting mechanisms. The second connecting mechanisms are welded to the corresponding welding positions. The second connecting mechanisms are pre-embedded in the external cast-in-place shear wall located on one side of the ladder body, so that the ladder body and the external cast-in-place shear wall are connected as one unit.

2. The prefabricated staircase as described in claim 1, characterized in that, The first connecting mechanism includes: Angle steel, which is installed in the mounting groove, has a first side plate and a second side plate that are connected to each other and integrally formed. The first side plate extends outward from the ladder body along the width direction of the ladder body and forms the welding position. The second side plate is provided with a through hole that runs vertically through the ladder body. The through hole corresponds to the position of the pre-embedded hole. An embedded component, which vertically passes through the through hole and extends into the corresponding embedded hole, to anchor the angle steel to the ladder body; and, A filler is provided to fill the mounting groove so as to pre-embed the angle steel in the mounting groove.

3. The prefabricated staircase as described in claim 2, characterized in that, The embedded components include: A binder block, the binder block filling the pre-embedded hole; and, An embedded screw rod is inserted into the through hole and one end of the screw rod is anchored in the adhesive block to anchor the angle steel to the ladder body.

4. The prefabricated staircase as described in claim 3, characterized in that, The cemented block is made of cement mortar or structural adhesive.

5. The prefabricated staircase as described in claim 4, characterized in that, The filler is made of cement mortar.

6. The prefabricated staircase as described in claim 5, characterized in that, The second connecting mechanism includes: Multiple connecting bolts are provided for connecting to the reinforcement cage of the external cast-in-place shear wall, and all connecting bolts extend outward along the thickness direction of the external cast-in-place shear wall to form an installation area on one side of the external cast-in-place shear wall; and, An anchor plate, which is connected to the connecting screw and located within the installation area, has one side of the anchor plate facing the angle steel for welding to the welding position of the angle steel.

7. The prefabricated staircase as described in any one of claims 1 to 6, characterized in that, A filling gap is also formed between the ladder body and the external cast-in-place shear wall, and a gap sealing component is installed in the filling gap.

8. The prefabricated staircase as described in claim 7, characterized in that, The gap sealing assembly includes a fireproof rock wool board, two PE rods and two layers of weather-resistant structural adhesive. The fireproof rock wool board is filled in the gap, and one of the PE rods is filled on each side of the fireproof rock wool board in the height direction. On the side of each PE rod away from the fireproof rock wool board, a layer of the weather-resistant structural adhesive is filled.

9. A construction method for a precast staircase, characterized in that, Used for constructing prefabricated stairs as described in any one of claims 1 to 8; The construction method includes the following steps: Provides an external load-bearing beam and an external cast-in-place shear wall that have reached a preset strength; wherein, the second connecting mechanism is pre-embedded in the external cast-in-place shear wall; The ladder body is hoisted and installed on the external load-bearing beam, so that the side of the ladder body with the installation groove is opposite to the external cast-in-place shear wall, and the filling gap is formed between the ladder body and the external cast-in-place shear wall. The first connecting mechanism is installed in each of the mounting slots; Each of the first connecting mechanisms is welded together with the corresponding second connecting mechanism. The gaps in the filling are sealed to complete the construction of the prefabricated staircase.

10. The construction method of the prefabricated staircase as described in claim 9, characterized in that, The step of sealing the filling gaps to complete the construction of the precast staircase includes: Mortar material is filled into the top opening of the mounting groove to connect the ladder body to the external cast-in-place shear wall as a whole; Fireproof rock wool boards are embedded in the filling gaps; Install a PE rod on each side of the fireproof rock wool board along its height. Weather-resistant sealant is filled on the side of each PE rod away from the fireproof rock wool board to complete the sealing of the filling gap.

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