A prefabricated staircase installation structure and installation method

Abstract

The present application relates to the technical field of assembled building, and particularly relates to a prefabricated stair installation structure and installation method, wherein the installation structure comprises prefabricated step monomers and step connecting pieces made of steel plate, the step connecting pieces connect adjacent prefabricated step monomers, the prefabricated step monomer comprises a horizontal step part, a vertical step part and an inclined step part, the horizontal step part is located between the vertical step part and the inclined step part, the vertical step part is connected with the horizontal step part perpendicularly, and the inclined step part is connected with the horizontal step part in an acute angle shape. The present application provides a prefabricated stair with good anti-seismic performance, and compared with a traditional concrete prefabricated stair which needs to be hoisted and transported by a crane and installed cooperatively, the prefabricated stair has the advantage of being manually disassembled and assembled throughout the whole process, thus saving energy and reducing pollutant emissions.

Description

Technical Field

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

[0002] Cast-in-place stairs, precast concrete (PC) stairs, and steel stairs are three commonly used stair types in prefabricated buildings. PC is an abbreviation for precast concrete, referred to as PC components in the residential industrialization field. Examples include precast reinforced concrete column foundations, precast steel structure column foundations, reinforced concrete foundations for streetlights and billboards, and precast floor slabs. In contrast, traditional cast-in-place concrete requires on-site formwork, pouring, and curing. Due to their high degree of standardization, precast concrete components can significantly shorten construction time and are therefore widely used in construction, transportation, water conservancy, and other fields, playing an important role in the national economy. Stairs are an indispensable element of buildings, and precast stairs have a high standardization rate; using industrialized production methods to manufacture precast stair slabs will inevitably bring considerable benefits.

[0003] Existing precast staircases, being monolithic concrete components, suffer from poor seismic resistance. Improving seismic resistance requires adding special seismic-resistant structures or processes at the connection points between the precast staircase and the floor slabs at both ends, leading to extended assembly times and increased costs. Therefore, a precast staircase with inherently good seismic performance is needed, independent of the structure or processes at the connection points between the precast staircase and the upper and lower platforms. However, this remains a challenging problem in the industry. Summary of the Invention

[0004] One of the objectives of this invention is to provide a prefabricated staircase installation structure, which aims to provide a prefabricated staircase with good seismic resistance.

[0005] This invention provides a prefabricated staircase installation structure, including prefabricated step units and step connectors made of steel plates. The step connectors connect adjacent prefabricated step units. Each prefabricated step unit includes a horizontal step portion, a vertical step portion, and an inclined step portion. The horizontal step portion is located between the vertical step portion and the inclined step portion. The vertical step portion and the horizontal step portion are vertically connected as one unit, and the inclined step portion and the horizontal step portion are connected as one unit at an acute angle.

[0006] The stepped connector includes a base plate, a first plate, a second plate, and a third plate integrally connected; the base plate is attached to the upper surface of the horizontal step portion, and the upper surface of the base plate is fixedly connected to the bottom of the vertical step portion; the first plate and the second plate are located above the base plate, and the first plate, the second plate, and the upper surface of the base plate form a first slot for the inclined step portion to be inserted, with a gap between the end of the inclined step portion and the deepest point of the first slot; the third plate is located below the base plate, and the third plate and the lower surface of the base plate form a second slot for the sharp corner formed by the horizontal step portion and the inclined step portion to be inserted, with a gap between the sharp corner and the deepest point of the second slot.

[0007] By adopting the above technical solution, seismic shear waves can cause horizontal ground shaking. Therefore, in the horizontal direction, the staircase may vibrate along its length or its width. When the staircase vibrates along its length, the bottommost prefabricated step unit is squeezed by the ground, and the vibration energy is transmitted upwards along each step. When the vibration intensity is small, the steel plate step connectors are squeezed and undergo elastic deformation, which is manifested in the first section repeatedly deforming upwards and then returning to its original shape, and the third section repeatedly deforming downwards and then returning to its original shape. When the vibration intensity is large, the steel plate step connectors are squeezed and undergo plastic deformation, which is manifested in the first section irreversibly deforming upwards and the third section irreversibly deforming downwards (the higher the earthquake magnitude, the more step connectors undergo plastic deformation from bottom to top). However, no matter how the first and third sections deform, the height of each step remains unchanged, and each prefabricated step unit is always in an interlocking state with the step connector, so the staircase will not collapse.

[0008] When the staircase vibrates along its width, the lowest prefabricated step unit moves laterally within the second slot of the step connector under the influence of the ground. As long as the width of the second slot allows, the prefabricated step unit will not detach from the step connector. After the earthquake, as the ground at the bottom of the staircase returns to its original position, the lowest prefabricated step unit will also return to its original position along with the ground.

[0009] Seismic P-waves cause the ground to bounce up and down. When the ground bounces upward, it causes the lowest layer of precast step units to move upward. The lowest layer of precast step units, through the step connectors, lifts the second layer of precast step units, causing the second layer of precast step units to rotate with the lower right corner of the third layer of precast step units as the fulcrum, with the rear end (the end away from the sharp corner) tilting upward and the front end (the sharp corner end) tilting downward. This causes the first and third plates of the step connectors to undergo elastic or plastic deformation. At the same time, the third layer of precast step units will also rotate similarly due to the upward force, but the rotation angle is smaller than that of the second layer of precast step units. The seismic wave energy is gradually consumed upward until it reaches the Nth layer of precast step units, where the energy is reduced to zero. When the ground bounces downward, the elastically deformed step connectors, after returning to their original shape, will hinder the movement of the precast step units, thus achieving an energy dissipation effect. The plastically deformed step connectors provide space for the movement of the precast step units of the next layer, reducing the efficiency of seismic wave energy transmission to the precast step units of the layer above.

[0010] After an earthquake, the steps that have undergone plastic deformation can be hammered back to their original shape. Although this method is not conducive to preventing the next earthquake, it can be used for temporary use of stairs. Once the installers and new steps are in place, the stairs can be disassembled and the steps can be replaced.

[0011] Optionally, the inclined step portion is provided with a first strip-shaped hole extending along the length of the staircase, and a first bolt penetrating the third plate is provided in the first strip-shaped hole. The diameter of the first bolt is smaller than the width of the first strip-shaped hole. A first nut is threaded onto the first bolt, and a first spring is sleeved on the first bolt. The first spring is pressed between the first nut and the third plate.

[0012] By adopting the above technical solution, when the staircase vibrates along its length, the first bolt moves along the length of the first strip hole, so that the relative movement between the precast step unit and the step connector is within the allowable safe range. When the relative movement of the two reaches the limit position allowed by the first strip hole, the precast step unit cannot continue to move in the direction of detaching from the step connector, but instead the precast step unit and the step connector exert force on the precast step unit of the next level. Therefore, the seismic wave energy is transmitted upward level by level, avoiding the collapse of the staircase caused by the first bolt being damaged by shear force when the seismic wave energy is concentrated on the lower level precast step unit.

[0013] When the staircase bounces vertically, the precast step unit pulls the first bolt upward, causing the first spring to be compressed and storing seismic wave energy. When the first spring is compressed to its limit, the seismic wave energy is transmitted upward step by step, avoiding the first bolt from breaking and causing the staircase to collapse when the seismic wave energy is concentrated on the lower precast step unit.

[0014] Since the first spring is pressed against the third plate, the energy stored in the first spring when it is compressed can reduce the deformation of the third plate, thus enabling the third plate to withstand greater seismic wave energy.

[0015] The diameter of the first bolt is designed to be smaller than the width of the first slot. This allows the first bolt to move in the width direction of the first slot, enabling the precast step unit to move relative to the step connector in the width direction of the staircase. This helps to mitigate the impact of seismic shear waves causing the staircase to vibrate along its width. When the first bolt moves to its limit in the width direction of the first slot, the precast step unit and the step connector temporarily unite as a whole, jointly exerting force on the next step. This allows the seismic wave energy to be transmitted upwards step by step, preventing the first bolt from being damaged by shear force and causing the staircase to collapse when the seismic wave energy is concentrated on the lower-level precast step unit.

[0016] Optionally, a second bolt is provided in the first strip hole, penetrating the first plate and the second plate. The diameter of the second bolt is smaller than the width of the first strip hole. A second nut is threaded onto the second bolt, and a second spring is fitted onto the second bolt and compressed by the second nut.

[0017] By adopting the above technical solution, since the precast step unit is a hollow precast step, when the precast step unit is subjected to pressure in the length direction of the staircase, the precast step unit will also undergo slight deformation, which will cause the depth of the inclined step part inserted into the first slot on the step connector to change, thereby causing the first plate to warp upwards and deform. After the second spring is compressed, the first plate is pulled towards the inclined step part through the second bolt, so that the first plate is not easy to undergo plastic deformation, that is, the first plate can resist higher-level earthquakes. The diameter of the second bolt is designed to be smaller than the width of the first strip hole, so as to allow the precast step unit to move relative to the step connector in the width direction of the staircase.

[0018] Optionally, the horizontal step portion is provided with a second strip-shaped hole extending along the length of the staircase, and a third bolt penetrating the base plate is provided in the second strip-shaped hole. The diameter of the third bolt is smaller than the width of the second strip-shaped hole, and a third nut is threaded onto the third bolt. A third spring is fitted onto the third bolt and compressed by the third nut.

[0019] By adopting the above technical solution, when the seismic longitudinal wave affects the staircase and causes the prefabricated step unit to rotate with the lower right corner of the previous step as the fulcrum, the third spring is compressed. The third spring restricts the rotation angle of the prefabricated step unit. When the prefabricated step unit rotates to the maximum angle, that is, when the third spring is compressed to the limit, the vertical vibration will not be able to continue to lift the prefabricated step unit upward. Instead, it will lift the previous step through the prefabricated step unit and cause the previous step to rotate. Therefore, the seismic wave energy is transmitted from bottom to top step by step, avoiding the collapse of the staircase caused by the third bolt being pulled off when the seismic wave energy is concentrated on the lower prefabricated step unit.

[0020] Optionally, the first plate is parallel to the second plate, and the first plate and the second plate are respectively attached to the upper and lower surfaces of the inclined step portion; the third plate is attached to the lower surface of the inclined step portion.

[0021] By adopting the above technical solution, the seamless insertion and matching of the precast step unit and the step connector maximizes the contact area between the two, and the force between them will be evenly distributed to all contact surfaces. When the lowest precast step unit moves due to the influence of seismic waves, the step connector is subjected to the force of the precast step unit evenly, and the force is evenly transmitted to the next step, so that the step connectors at all steps can deform and relieve the force evenly.

[0022] Optionally, the lower surface of the first plate is provided with a first rounded corner at the connection between it and the upper surface of the substrate; the upper surface of the third plate is provided with a second rounded corner at the connection between it and the lower surface of the substrate.

[0023] By adopting the above technical solution, the rounded corners increase the thickness at the included angles, making the stepped connector less prone to cracking at the included angles during deformation.

[0024] Optionally, the precast step unit comprises a concrete outer layer and a steel sandwich panel, wherein the steel sandwich panel has an array of holes.

[0025] By adopting the above technical solution, the steel sandwich panel improves the toughness of the precast step unit, enabling the precast step unit to have a greater elastic deformation in the length direction of the staircase, thereby converting more seismic wave energy into elastic potential energy and storing it, thus reducing the seismic wave energy transmitted to the next step.

[0026] Optionally, the substrate and the steel sandwich panel are integrally formed.

[0027] By adopting the above technical solution, the step of welding the substrate and the steel sandwich panel on site is eliminated.

[0028] Optionally, the substrate and the steel sandwich panel are fixedly connected by welding, and the outer concrete layer has a notch that exposes the welding position.

[0029] By adopting the above technical solution, it is convenient to manufacture prefabricated step units and step connectors separately, and the separate stacking and transportation of the two also saves more space.

[0030] The second objective of this invention is to provide a method for installing prefabricated stairs, which aims to solve the problem that the upper surface of the top-floor prefabricated step unit is not flush with the installation platform at a high altitude.

[0031] This invention provides a method for installing prefabricated stairs, including the aforementioned prefabricated step units and step connectors, with the following installation steps:

[0032] Step 1. Open a first groove on the upper surface of the lower first installation platform, so that a slope is formed in the first groove, and drill multiple holes vertically on the slope, and insert the first steel bar into the holes by grouting;

[0033] Step 2. Take one of the stepped connectors, drill holes on its third plate that correspond one-to-one with the first reinforcing bar, place the third plate against the inclined surface, and let the first reinforcing bar pass through the hole through the third plate;

[0034] Step 3. Adjust the base plate of the stepped connector to be flush with the upper surface of the first mounting platform by using padding material;

[0035] Step 4. Pour concrete into the first groove and wait for the concrete to solidify and cure.

[0036] Step 5. After the concrete has solidified, assemble the stairs upwards based on the step connectors until the distance between the top surface of the stairs and the upper surface of the higher second installation platform is less than the height of one of the precast step units.

[0037] Step 6. Measure the distance, divide it by the number of steps to obtain the average height that each prefabricated step needs to be raised, and customize a pad of corresponding thickness;

[0038] Step 7. Place the pad between the upper surface of the prefabricated step unit and the substrate;

[0039] Step 8. A second groove is made on the second installation platform for the insertion of the top prefabricated step unit of the staircase. A second steel bar is inserted into the cavity of the top prefabricated step unit. Slots are made on both sides of the second groove to place the second steel bar.

[0040] Step 9. Seal the sides of the second groove with a concrete formwork, fill the second groove with concrete, and wait for the concrete to solidify and cure.

[0041] By adopting the above technical solution, using a steel structure in conjunction with cast-in-place concrete, the two ends of the staircase are fixed to the first and second installation platforms respectively. It also takes advantage of the fact that when the prefabricated step unit and the step connector are plugged in, the step can be raised with a pad, without affecting the normal plugging and connection between the prefabricated step unit and the step connector, or affecting the horizontal posture of the upper surface of the step. Therefore, the height of each step can be freely adjusted, so that the upper surface of the prefabricated step unit on the top floor is flush with the installation platform at the top. Attached Figure Description

[0042] Figure 1 This is a front view of the prefabricated staircase installation structure in the embodiment;

[0043] Figure 2 This is a front view of the prefabricated step unit and step connector assembled in the embodiment;

[0044] Figure 3 This is a perspective view of the prefabricated staircase installation structure in the embodiment;

[0045] Figure 4 for Figure 3 Enlarged view of section A in the middle;

[0046] Figure 5 This is a schematic diagram illustrating the connection between the step connector and the first mounting platform in the embodiment.

[0047] Figure 6 This is a schematic diagram showing the connection between the prefabricated step unit and the second installation platform in the embodiment.

[0048] Reference numerals: 1. Precast step unit; 1a. Concrete outer layer; 1b. Steel sandwich panel; 11. Horizontal step section; 111. Second strip hole; 12. Vertical step section; 13. Inclined step section; 131. First strip hole;

[0049] 2. Step connector; 21. Base plate; 22. First plate; 23. Second plate; 24. Third plate; 25. First slot; 26. Second slot; 27. Gap; 28. First fillet; 29. ​​Second fillet;

[0050] 31. First bolt; 32. First nut; 33. First spring;

[0051] 41. Second bolt; 42. Second nut; 43. Second spring;

[0052] 51. Third bolt; 52. Third nut; 53. Third spring;

[0053] 6. First mounting platform; 61. First groove; 62. Inclined surface; 7. Second mounting platform; 71. Second groove; 72. Slot; 8. First reinforcing bar; 9. Second reinforcing bar. Implementation

[0054] 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0055] It should be noted that in this article, relational terms such as “first” and “second” are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Example

[0056] This invention provides a prefabricated staircase installation structure, referring to... Figure 1 It includes multiple prefabricated step units 1 and multiple step connectors 2.

[0057] Reference Figure 2 The precast step unit 1 consists of a steel sandwich panel 1b and an outer concrete layer 1a. The steel sandwich panel 1b has arrayed holes through which the concrete passes, thus firmly bonding with the steel sandwich panel 1b without peeling off. The precast step unit 1 is composed of a vertical step section 12, a horizontal step section 11, and an inclined step section 13 connected sequentially, with the bottom of the vertical step section 12 not connected to the bottom of the inclined step section 13. In the staircase, the outer wall of the vertical step section 12 is vertical, the upper surface of the horizontal step section 11 is horizontal, and the inclined step section 13 is connected to the horizontal step section 11 at an acute angle. At the connection between the vertical step section 12 and the horizontal step section 11, the steel sandwich panel 1b is at a right angle; this design aims to improve the ability of the upper surface of the precast step unit 1 to withstand vertical pressure. At the connection between the horizontal step portion 11 and the inclined step portion 13, the steel sandwich plate 1b has an arc-shaped bend. The purpose of this design is to make the arc-shaped bend more easily deformed when subjected to horizontal pressure, so as to convert the seismic wave energy that causes the pressure into elastic potential energy and temporarily store it.

[0058] Reference Figure 1 and Figure 2The step connector 2 is made of steel plate and is used to connect adjacent prefabricated step units 1. The step connector 2 is integrally formed from a base plate 21, a first plate 22, a second plate 23, and a third plate 24. The first plate 22 and the second plate 23 are parallel, and the first plate 22 and the second plate 23 are respectively attached to the upper and lower surfaces of the inclined step portion 13. The third plate 24 is attached to the lower surface of the next layer of inclined step portion 13. A first rounded corner 28 is provided at the connection between the lower surface of the first plate 22 and the upper surface of the base plate 21; a second rounded corner 29 is provided at the connection between the upper surface of the third plate 24 and the lower surface of the base plate 21. The rounded corners increase the thickness at the included angle, making the step connector 2 less prone to cracking at the included angle during deformation. Forging the step connector 2 from a single steel ingot is the optimal process because the step connector 2 needs to have strong toughness and a large elastic deformation.

[0059] Reference Figure 1 and Figure 2 During installation, the substrate 21 is attached to the upper surface of the horizontal step portion 11, and the upper surface of the substrate 21 is vertically fixedly connected to the bottom of the vertical step portion 12. The first plate 22 and the second plate 23 are located above the substrate 21. The first plate 22, the second plate 23, and the upper surface of the substrate 21 form a first slot 25 for the inclined step portion 13 to be inserted. The inclined step portion 13 does not occupy all the space of the first slot 25, and there is a gap 27 between the end of the inclined step portion 13 and the deepest part of the first slot 25. The third plate 24 is located below the substrate 21. The third plate 24 and the lower surface of the substrate 21 form a second slot 26 for the pointed corner formed by the horizontal step portion 11 and the inclined step portion 13 to be inserted. The pointed corner does not occupy all the space of the second slot 26, and there is a gap 27 between the pointed corner and the deepest part of the second slot 26.

[0060] Reference Figure 2 The step connector 2 and the steel sandwich plate 1b can be manufactured separately and then welded after arriving at the installation site. In this case, a gap is reserved at the bottom of the outer concrete layer 1a to expose the connection seam between the steel sandwich plate 1b and the step connector 2, so as to facilitate the filling of the weld.

[0061] Reference Figure 2 The step connector 2 and the steel sandwich panel 1b can also be integrally formed. During production, a straight steel plate is first forged on the base plate 21, and then the straight steel plate is bent into the shape of the steel sandwich panel 1b. Then, holes are punched on the steel sandwich panel 1b, and finally the steel sandwich panel 1b is sandwiched in the concrete mold and solidified with the concrete to form a precast step unit 1.

[0062] Reference Figure 3 and Figure 4The inclined step 13 has a first strip-shaped hole 131 extending along the length of the staircase. The first strip-shaped hole 131 is punched in the steel sandwich plate 1b during production, and the concrete mold is designed to avoid this hole. A first bolt 31, penetrating the third plate 24, is installed in the first strip-shaped hole 131. The diameter of the first bolt 31 is smaller than the width of the first strip-shaped hole 131. A first nut 32 is threaded onto the first bolt 31, and a first spring 33 is fitted onto the first bolt 31, pressing between the first nut 32 and the third plate 24.

[0063] Reference Figure 4 When the staircase vibrates along its length, the first bolt 31 moves along the length of the first strip hole 131, ensuring that the relative movement between the precast step unit 1 and the step connector 2 is within the allowable safe range. When the relative movement reaches the allowable limit position of the first strip hole 131, the precast step unit 1 can no longer move in the direction of detaching from the step connector 2, but instead, the precast step unit 1, together with the step connector 2, exerts a force on the upper-level precast step unit 1, thus transmitting the seismic wave energy upwards step by step. This prevents the first bolt 31 from being broken by shear force when the seismic wave energy is concentrated on the lower-level precast step unit 1, thus preventing the staircase from collapsing. When the staircase jumps vertically, the precast step unit 1 pulls the first bolt 31 upwards, causing the first spring 33 to be compressed and storing seismic wave energy. When the first spring 33 is compressed to its limit, the seismic wave energy is transmitted upwards step by step, preventing the first bolt 31 from being broken when the seismic wave energy is concentrated on the lower-level precast step unit 1, thus preventing the staircase from collapsing.

[0064] Reference Figure 4 Since the first spring 33 is pressed against the third plate 24, the energy stored in the first spring 33 when compressed can reduce the deformation of the third plate 24, thus enabling the third plate 24 to withstand greater seismic wave energy. The diameter of the first bolt 31 is designed to be smaller than the width of the first slot 131, so that the first bolt 31 can move in the width direction of the first slot 131, thereby allowing the prefabricated step unit 1 to move relative to the step connector 2 in the width direction of the staircase, thus coping with the influence of seismic transverse waves causing the staircase to vibrate in the width direction. When the first bolt 31 moves to its limit in the width direction of the first slot 131, the prefabricated step unit 1 and the step connector 2 temporarily unite as a whole, jointly exerting force on the upper step, thereby transmitting the seismic wave energy upward step by step, avoiding the first bolt 31 being damaged by shear force when the seismic wave energy is concentrated on the lower prefabricated step unit 1, which would lead to the collapse of the staircase.

[0065] Reference Figure 4A second bolt 41, penetrating the first plate 22 and the second plate 23, is also provided in the first slot 131. The diameter of the second bolt 41 is smaller than the width of the first slot 131. A second nut 42 is threaded onto the second bolt 41, and a second spring 43 is fitted onto the second bolt 41. The second spring 43 is pressed between the second nut 42 and the second plate 23. Since the precast step unit 1 is a hollow precast step, when the precast step unit 1 is subjected to pressure in the length direction of the staircase, the precast step unit 1 will also undergo slight deformation, causing the depth of the inclined step part 13 inserted into the first slot 25 on the step connector 2 to change. This causes the first plate 22 to warp upwards. After the second spring 43 is compressed, it pulls the first plate 22 toward the inclined step part 13 through the second bolt 41, thus making the first plate 22 less prone to plastic deformation, i.e., the first plate 22 can resist higher-level earthquakes. The diameter of the second bolt 41 is designed to be smaller than the width of the first slot 131 in order to allow the precast step unit 1 to move relative to the step connector 2 in the width direction of the staircase.

[0066] Reference Figure 4 The horizontal step portion 11 is provided with a second strip-shaped hole 111 extending along the length of the staircase. A third bolt 51 penetrating the base plate 21 is provided in the second strip-shaped hole 111. The diameter of the third bolt 51 is smaller than the width of the second strip-shaped hole 111. A third nut 52 is threaded onto the third bolt 51. A third spring 53 is sleeved on the third bolt 51. The third spring 53 is pressed between the third nut 52 and the base plate 21. When the longitudinal wave of the earthquake affects the staircase, causing the precast step unit 1 to rotate counterclockwise with the lower right corner of the previous step as the fulcrum, the third spring 53 is compressed. The third spring 53 limits the rotation angle of the precast step unit 1. When the precast step unit 1 rotates to the maximum angle, that is, when the third spring 53 is compressed to the limit, the vertical vibration will no longer be able to lift the right end of the precast step unit 1. Instead, it will lift the previous step through the precast step unit 1 and cause the previous step to rotate. Therefore, the seismic wave energy is transmitted from bottom to top step by step, avoiding the third bolt 51 from breaking and causing the staircase to collapse when the seismic wave energy is concentrated on the lower precast step unit 1.

[0067] The installation method for the above-mentioned prefabricated staircase installation structure is as follows:

[0068] First step, refer to Figure 3 A first groove 61 is opened on the upper surface of the lower first installation platform 6, so that the inner wall of the first groove 61 near the stairs forms a slope 62. Multiple holes are drilled vertically on the slope 62, and the first steel bar 8 is inserted into the holes by grouting.

[0069] The second step, refer to Figure 3Take a step connector 2, drill holes on its third plate 24 that correspond one-to-one with the first steel bar 8, place the third plate 24 against the inclined surface 62, and let the first steel bar 8 pass through the holes through the third plate 24.

[0070] Third step, refer to Figure 3 By placing an object between the lower surface of the third plate 24 and the inclined surface 62, the base plate 21 of the step connector 2 is adjusted to be flush with the upper surface of the first mounting platform 6.

[0071] Step 4, refer to Figure 3 Pour concrete into the first groove 61 and wait for the concrete to solidify and cure.

[0072] Step 5, refer to Figure 5 After the concrete has solidified, the stairs are assembled upwards based on the step connector 2. The assembly process involves inserting the precast step unit 1 of the lower layer into the step connector 2 of the upper layer, and then assembling all the bolts, nuts and springs on both layers of steps until the distance between the top surface of the stairs and the upper surface of the higher second installation platform 7 is less than the height of one precast step unit 1. If the bolts on the bottom step cannot be installed due to interference with the first installation platform 6, a groove can be cut on the first installation platform 6 to avoid the bolts, or the bolts can be omitted and the precast step unit 1 and the step connector 2 can be directly fixed by welding.

[0073] Step 6, refer to Figure 5 Measure the distance between the top surface of the staircase and the upper surface of the second installation platform 7, divide it by the number of steps to obtain the average height that each prefabricated step unit 1 needs to be raised, and customize the corresponding thickness of the pad.

[0074] Step 7: Place the pad between the upper surface of the prefabricated step unit 1 and the substrate 21;

[0075] Step 8, refer to Figure 6 A second groove 71 is opened on the second installation platform 7 for the insertion of the top prefabricated step unit 1 of the staircase. Multiple second steel bars 9 are inserted into the cavity of the top prefabricated step unit 1. The second steel bars 9 are placed in slots 72 on both sides of the second groove 71.

[0076] Step 9: Seal the sides of the second groove 71 with concrete formwork, fill the second groove 71 with concrete, and wait for the concrete to solidify and cure.

[0077] The above installation method uses a steel structure combined with cast-in-place concrete to fix the two ends of the staircase to the first installation platform 6 and the second installation platform 7 respectively. It also takes advantage of the fact that when the prefabricated step unit 1 and the step connector 2 are plugged in, the step can be raised with a pad. This does not affect the normal plugging and connection between the prefabricated step unit 1 and the step connector 2, nor does it affect the horizontal posture of the upper surface of the step. Therefore, the height of each step can be freely adjusted, so that the upper surface of the prefabricated step unit 1 on the top floor is flush with the installation platform at the top.

[0078] In summary, the prefabricated staircase installation structure provided by this invention has the following working principle and advantages:

[0079] Earthquake shear waves can cause horizontal ground shaking. Therefore, in the horizontal direction, the staircase may vibrate along its length or its width. When the staircase vibrates along its length, the lowest prefabricated step 1 is compressed by the ground and presses against the step connector 2. The vibration energy is transmitted upwards along each step. When the vibration is small, the steel plate step connector 2 is compressed and undergoes elastic deformation, which is manifested in the first plate 22 repeatedly deforming upwards and then returning to its original shape, and the third plate 24 repeatedly deforming downwards and then returning to its original shape. When the vibration is large, the steel plate step connector 2 is compressed and undergoes plastic deformation, which is manifested in the first plate 22 irreversibly deforming upwards and the third plate 24 irreversibly deforming downwards (the higher the earthquake magnitude, the more step connectors 2 undergo plastic deformation from bottom to top). However, no matter how the first plate 22 and the third plate 24 deform, the height of each step remains unchanged, and each prefabricated step 1 is always in an interlocking state with the step connector 2. Therefore, the staircase will not collapse.

[0080] When the staircase vibrates along its width, the lowest prefabricated step unit 1 moves laterally within the second slot 26 of the step connector 2 under the influence of the ground. Under the limiting effect of the width of the first strip hole 131 on the first bolt 31 and the second bolt 41, the prefabricated step unit 1 will not detach from the step connector 2. After the earthquake, as the ground at the bottom of the staircase returns to its original position, the lowest prefabricated step unit 1 will also return to its original position along with the ground.

[0081] The longitudinal waves of the earthquake cause the ground to bounce up and down. When the ground bounces upward, it causes the lowest precast step unit 1 to move upward. The lowest precast step unit 1, through the step connector 2, lifts the second precast step unit 1, causing the second precast step unit 1 to rotate counterclockwise with its rear end (the end away from the sharp corner) tilting upward and its front end (the sharp corner end) sinking, using the lower right corner of the third precast step unit 1 as a fulcrum. This causes the first plate 22 and the third plate 24 of the step connector 2 to undergo elastic or plastic deformation. At the same time, the third precast step unit... 1. When subjected to an upward force, a similar rotation will occur, but the rotation angle is smaller than that of the second-layer precast step unit 1. The seismic wave energy is consumed upward step by step until it reaches the Nth-layer precast step unit 1, at which point the energy is reduced to zero. When the ground jumps downward, the elastically deformed step connector 2 will restore its original shape and hinder the movement of the precast step unit 1, thereby achieving the energy dissipation effect. The plastically deformed step connector 2 provides space for the movement of the next layer of precast step unit 1, reducing the efficiency of the seismic wave energy transmission to the layer above it.

[0082] After the earthquake, the step connector 2 that has undergone plastic deformation can be hammered to restore it to its original shape. Although this method is not conducive to defending against the next earthquake, it can be used for temporary use of the stairs. When the installation workers and the new step connector 2 are in place, the stairs can be disassembled and the step connector 2 can be replaced.

[0083] The prefabricated staircase installation structure provided by this invention has the advantage of being able to be manually disassembled and assembled throughout the entire process, compared to traditional prefabricated concrete staircases that require cranes for hoisting, transportation, and installation. This saves energy and reduces pollutant emissions.

[0084] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A prefabricated stair installation structure, comprising prefabricated step monomers (1) and step connecting pieces (2) made of steel plate material, the step connecting pieces (2) connecting adjacent prefabricated step monomers (1), characterized in that the prefabricated step monomers (1) comprise a horizontal step part (11), a vertical step part (12) and an inclined step part (13), the horizontal step part (11) being located between the vertical step part (12) and the inclined step part (13), the vertical step part (12) being connected perpendicularly to the horizontal step part (11), and the inclined step part (13) being connected to the horizontal step part (11) at an acute angle; the step connecting piece (2) comprises a base plate (21), a first plate (22), a second plate (23) and a third plate (24) connected as one; the upper surface of the base plate (21) is fixedly connected to the bottom of the vertical step part (12); the first plate (22) and the second plate (23) are located above the base plate (21), the first plate (22), the second plate (23) and the upper surface of the base plate (21) form a first slot (25) for inserting the inclined step part (13), and there is a gap (27) between the end of the inclined step part (13) and the deepest part of the first slot (25); the third plate (24) is located below the base plate (21), the third plate (24) and the lower surface of the base plate (21) form a second slot (26) for inserting the acute angle formed by the horizontal step part (11) and the inclined step part (13), there is a gap (27) between the acute angle and the deepest part of the second slot (26), and the base plate (21) is attached to the upper surface of the horizontal step part (11); the inclined step part (13) is provided with a first slot (131) extending along the length direction of the stair, the first slot (131) is provided with a first bolt (31) penetrating through the third plate (24), the diameter of the first bolt (31) is smaller than the width of the first slot (131), the first bolt (31) is threadedly connected with a first nut (32), and the first bolt (31) is sleeved with a first spring (33) which is compressed between the first nut (32) and the third plate (24); the first slot (131) is also provided with a second bolt (41) penetrating through the first plate (22) and the second plate (23), the diameter of the second bolt (41) is smaller than the width of the first slot (131), the second bolt (41) is threadedly connected with a second nut (42), and the second bolt (41) is sleeved with a second spring (43) which is compressed by the second nut (42). ​ ​ ​ ​ The water platform step (11) is provided with a second strip-shaped hole (111) extending along the length direction of the stair, the second strip-shaped hole (111) is provided with a third bolt (51) penetrating the base plate (21), the diameter of the third bolt (51) is smaller than the width of the second strip-shaped hole (111), the third bolt (51) is threadedly connected with a third nut (52), and the third bolt (51) is sleeved with a third spring (53) compressed by the third nut (52).

2. A pre-fabricated stair installation structure as claimed in claim 1, wherein, The first plate (22) and the second plate (23) are parallel, and the first plate (22) and the second plate (23) are respectively attached to the upper and lower surfaces of the inclined step portion (13); and the third plate (24) is attached to the lower surface of the inclined step portion (13).

3. A pre-fabricated stair installation structure as claimed in claim 1, wherein, A first round corner (28) is arranged at the junction between the lower surface of the first plate (22) and the upper surface of the base plate (21); and a second round corner (29) is arranged at the junction between the upper surface of the third plate (24) and the lower surface of the base plate (21).

4. A pre-fabricated stair installation structure according to any one of claims 1 to 3, wherein The prefabricated step monomer (1) comprises a concrete outer layer (1a) and a steel sandwich plate (1b), and the steel sandwich plate (1b) is arrayed with holes.

5. A pre-fabricated stair installation structure as claimed in claim 4, wherein, The base plate (21) and the steel sandwich plate (1b) are integrally formed.

6. A pre-fabricated stair installation structure as claimed in claim 4, wherein, The base plate (21) and the steel sandwich plate (1b) are fixedly connected by welding, and the concrete outer layer (1a) is provided with a notch exposing the welding position.

7. A method for installing a prefabricated staircase, comprising the prefabricated step unit (1) and the step connector (2) according to any one of claims 1-6, characterized in that, The installation steps are as follows: Step 1. A first recess (61) is formed on the upper surface of a lower first installation platform (6), a slope (62) is formed in the first recess (61), a plurality of holes are vertically drilled on the slope (62), and a first steel bar (8) is implanted in the holes by grouting; Step 2. One of the step connectors (2) is taken, holes corresponding to the first steel bars (8) are drilled on the third plate (24) of the step connector (2), the third plate (24) is placed against the slope (62), and the first steel bars (8) penetrate the third plate (24) through the holes; Step 3. The base plate (21) of the step connector (2) is adjusted to be flush with the upper surface of the first installation platform (6) by cushioning treatment; Step 4. The first recess (61) is filled with concrete, and the concrete is allowed to solidify and be cured; Step 5. After the concrete solidifies, the stairs are assembled upwards based on the step connector (2) until the distance between the top surface of the stairs and the upper surface of a higher second installation platform (7) is less than the height of one prefabricated step monomer (1); Step 6. The distance is measured and divided by the number of steps to obtain the average height by which each prefabricated step monomer (1) needs to be raised, and a corresponding thickness of a pad is customized; Step 7. The pad is placed between the upper surface of the prefabricated step monomer (1) and the base plate (21). Step8. Open a second recess (71) on the second installation platform (7) for inserting the highest layer of prefabricated step monomer (1) of the staircase, insert the second steel bar (9) in the cavity of the highest layer of prefabricated step monomer (1), and open a clamping groove (72) on the two side walls of the second recess (71) to place the second steel bar (9); Step9. Close the side of the second recess (71) with a concrete form, fill the second recess (71) with concrete, and wait for the concrete to solidify and be cured.

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