Basement thick bottom plate side mold device and construction method thereof

Abstract

The invention provides a basement thick bottom plate side formwork device and a construction method thereof.The basement thick bottom plate side formwork device comprises a brick forming die unit which is built along the side edge of a bottom plate, the height of the brick forming die unit is matched with the thickness of the bottom plate, and the brick forming die unit comprises a first-step brick forming die and a second-step brick forming die which are arranged in a stacked mode; the supporting unit is arranged on the outer side of the brick blank membrane unit, is used for resisting lateral pressure of concrete and is connected with a shotcrete anchor protection slope; the waterproof unit is arranged on the inner side of the brick blank membrane unit and comprises a waterproof mortar plastering layer and a waterproof roll layer; plastic cloth is further arranged above the waterproof roll layer, and the second-step brick blank film covers the plastic cloth. According to the side formwork device for the thick bottom plate of the basement, the overall rigidity and the side pressure resistance of the side formwork are remarkably improved, a brick forming die is effectively prevented from cracking, and the structural stability of the joint of the bottom plate and the side wall is enhanced; the integral waterproof effect of the basement can be greatly improved, the construction efficiency is high, and the material utilization rate is high.

Description

Technical Field

[0001] This application belongs to the field of building construction technology, specifically relating to a side formwork structure and construction method suitable for thick base slabs of civil defense basements and ordinary large basements, especially for engineering scenarios with large base slab thickness, high lateral pressure and strict waterproofing requirements. Background Technology

[0002] With the comprehensive development and utilization of urban underground space, civil defense basements have gradually transformed from single-purpose wartime facilities into integrated urban underground disaster prevention spaces that combine peacetime and wartime functions and integrate multiple functions. Their design concept has also evolved from the traditional "civil defense" to "multi-defense integration," placing higher demands on the waterproofness, durability, and construction quality of the structure.

[0003] However, in actual construction, especially at the junction of the basement floor slab and side walls in large basements, problems such as high lateral pressure of concrete, easy cracking of traditional brick formwork, and improper connection of waterproof layer construction often lead to potential leakage risks, affecting the later use function and structural safety of the building.

[0004] In existing technologies, side formwork support often uses temporary wooden formwork or simple brick formwork, lacking a systematic integrated design for reinforcement and waterproofing, making it difficult to meet the dual requirements of lateral pressure resistance and waterproofing in the construction of thick slabs. Therefore, there is an urgent need for a side formwork system and supporting construction methods that are structurally sound, easy to construct, waterproof reliably, and provide stable support. Summary of the Invention

[0005] This application provides a side formwork device for a thick basement slab and its construction method, which solves the technical problem in the prior art that brick formwork is prone to cracking due to insufficient lateral pressure resistance during the construction of thick base slabs, and that the connection with the waterproof layer is discontinuous, resulting in a high risk of structural leakage.

[0006] To solve at least one of the above-mentioned technical problems, the technical solution adopted in this application is:

[0007] A basement thick floor slab side formwork device includes: a brick formwork unit, which is built along the side of the floor slab and whose height is adapted to the thickness of the floor slab, including a first step brick formwork and a second step brick formwork stacked together;

[0008] A support unit is set on the outside of the brick formwork unit to resist the lateral pressure of the concrete and to connect with the shotcrete slope protection.

[0009] A waterproof unit is set inside the brick formwork unit, including a waterproof mortar plastering layer and a waterproof membrane layer; a plastic sheet is also provided above the waterproof membrane layer, and the second brick formwork covers the plastic sheet.

[0010] Furthermore, the first step brick formwork is laid to the same height as the base slab thickness, and the second step brick formwork is laid to the height of one brick layer, used to cover and protect the waterproof membrane layer.

[0011] Furthermore, the support unit includes:

[0012] The secondary rib square steel, the main rib square steel, the steel pipe, and the adjustable top support are arranged on the outside of the brick membrane unit. The secondary rib square steel is arranged horizontally along the brick membrane unit, and the main rib square steel is arranged vertically along the brick membrane unit. One end of the steel pipe is provided with the adjustable top support to support the main rib square steel, and the other end is connected to the shotcrete and anchor slope protection.

[0013] Furthermore, both the secondary rib square steel and the primary rib square steel are 40mm square steel, the spacing between adjacent secondary rib square steel is 300mm, and the spacing between adjacent primary rib square steel is 1200mm.

[0014] Furthermore, a horizontally embedded sleeve is pre-embedded in the sprayed and anchored slope protection, and the steel pipe is inserted into the sprayed and anchored slope protection through the embedded sleeve; wherein, the diameter of the embedded sleeve is 2-5mm larger than the diameter of the steel pipe.

[0015] Furthermore, a wooden board is placed between the pre-embedded sleeve and the sprayed anchor slope protection; a slope protection steel bar is provided at the middle position of the thickness of the sprayed anchor slope protection, which is not connected to the wooden board.

[0016] Furthermore, in the waterproof unit, the waterproof mortar plastering layer is applied to the inside of the brick formwork unit and intersects with the padding layer; the waterproof membrane layer is laid on the waterproof mortar plastering layer and turned up to the top of the first step brick formwork.

[0017] Furthermore, the plastic sheet is laid between the waterproof membrane layer and the second step brick formwork to protect the waterproof membrane layer from damage during removal.

[0018] A method for constructing side formwork for a thick basement slab, using the side formwork device described above, includes the following steps:

[0019] S1. Lay the first brick formwork according to the thickness of the base plate;

[0020] S2. Install the secondary rib square steel, main rib square steel, steel pipe and adjustable top support in the support unit on the outside of the first step brick formwork, so that the secondary rib square steel and the main rib square steel are arranged crosswise on the outer layer of the first step brick formwork, and the main rib square steel is supported by the adjustable top support.

[0021] S3. Apply a waterproof mortar plaster layer to the inside of the brick formwork in the first step, lay the waterproof membrane layer and turn it up to form a waterproof unit.

[0022] S4. Lay the plastic sheet on the waterproof membrane layer, and then build the second step brickwork on the plastic sheet;

[0023] S5. Install the slope protection reinforcement bars, and then pour the concrete.

[0024] S6. After the concrete hardens, remove the support unit for future reuse.

[0025] Furthermore, in the support unit, the steel pipe is connected to the sprayed and anchored slope protection through a pre-embedded sleeve, and a wooden board is placed at the connection between the steel pipe and the sprayed and anchored slope protection, but it is not connected to the slope protection reinforcement; a section of the waterproof membrane layer is reserved at the top of the first step brick formwork, which overlaps with the subsequent wall waterproof membrane layer to form a continuous waterproof unit.

[0026] The basement thick floor slab side formwork device designed in this application, by combining brick formwork units with support units, can significantly improve the overall rigidity and lateral pressure resistance of the side formwork, effectively prevent the brick formwork from cracking, and thus enhance the structural stability at the junction of the floor slab and the side wall.

[0027] Furthermore, by replacing ordinary plaster with waterproof mortar and forming a double waterproof layer with the upturned waterproof membrane, the continuity and reliability of the waterproof structure were achieved, significantly improving the overall waterproofing effect of the basement. Simultaneously, by placing plastic sheeting between the waterproof membrane and the second-step brick formwork, both physical protection of the waterproof unit and ease of subsequent removal and construction are achieved, preventing damage to the waterproof membrane layer and improving construction efficiency and material utilization.

[0028] Furthermore, the support unit achieves a detachable connection with the shotcrete slope protection through adjustable top supports and pre-embedded sleeves, ensuring not only stable installation but also reusability, reducing construction costs and embodying the concept of green construction. This application can guarantee construction quality while also being economical, operable, and durable, and is applicable to various large basement projects, especially civil defense basement projects. This application also proposes a construction method for a side formwork device for a thick basement floor slab. Attached Figure Description

[0029] Figure 1 This is a structural schematic diagram of a basement thick floor slab side formwork device according to this application;

[0030] Figure 2 This is a schematic diagram of the steel pipe pre-embedded in the support unit in this application.

[0031] In the diagram: 10. Brick formwork unit; 11. First-stage brick formwork; 12. Second-stage brick formwork; 20. Support unit; 21. Secondary square steel; 22. Main square steel; 23. Steel pipe; 24. Adjustable top support; 30. Waterproofing unit; 31. Waterproof membrane layer; 32. Waterproof mortar plastering layer; 33. Plastic sheet; 40. Subbase; 50. Shotcrete and anchor slope protection; 51. Embedded sleeve; 52. Wooden board; 53. Slope protection reinforcement; 60. Base. Detailed Implementation

[0032] The present application will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0033] Based on the structural characteristics of this embodiment, a 240mm brick formwork is used for the side formwork of the base slab. Due to the large volume of the base slab, the brick formwork is insufficient to support the lateral pressure of the concrete, so reinforcement is required on one side of the brick formwork. This embodiment proposes a side formwork device for a thick basement slab, such as... Figure 1-2 As shown, the structure includes a brick formwork unit 10, a support unit 20, a waterproof unit 30, and a sprayed and anchored slope protection 50. The brick formwork unit 10 is constructed in two steps: the first step, brick formwork 11, is constructed at the same height as the base slab; the second step, brick formwork 12, is constructed to cover the waterproof membrane. The support unit 20 consists of several secondary square steel bars 21, main square steel bars 22, steel pipes 23, and adjustable top supports 24. It is connected to the sprayed and anchored slope protection 50 via pre-embedded sleeves 51 to resist lateral pressure from the concrete. The waterproof unit 30 has a waterproof mortar plaster layer 32 and a waterproof membrane layer 31 on the inside of the brick formwork. The membrane is turned up to the top of the first step brick formwork 11 to achieve continuous waterproofing. A plastic sheet 33 is laid on the waterproof membrane before the second step brick formwork 12 is constructed to prevent damage to the waterproof layer during removal.

[0034] Specifically, the brick formwork unit 10 is constructed along the side of the base slab, with its height adapted to the thickness of the base slab. It includes a first-step brick formwork 11 and a second-step brick formwork 12, which are stacked one on top of the other. The purpose of constructing the second-step brick formwork 12 is to protect the waterproof membrane layer 31 that extends to the top of the first-step brick formwork 11. The construction height of the first-step brick formwork 11 is consistent with the thickness of the base slab, and the construction height of the second-step brick formwork 12 is the height of one brick layer, used to cover and protect the waterproof membrane layer.

[0035] The support unit 20 consists of secondary square steel 21, main square steel 22, circular steel pipe 23, and adjustable top support 24; it is reliably connected to the sprayed and anchored slope protection 50 through a pre-embedded sleeve 51. The waterproof unit 30 includes an inner waterproof mortar plaster layer 32, a waterproof membrane layer 31 wrapped around the waterproof mortar plaster layer 32, and a plastic sheet 33 covering part of the waterproof membrane layer 31. The waterproof membrane layer 31 is turned up to the top of the first-step brick formwork 11 with a reserved overlap section; the plastic sheet 33 is placed on the turned-up section of the waterproof membrane layer 31, and the second-step brick formwork 12 is covered on the plastic sheet 33. The purpose of the plastic sheet 33 is to prevent damage to the waterproof membrane layer 31 during removal. The support unit 20 can effectively disperse the lateral pressure of the concrete, prevent the brick formwork from cracking, and indirectly improve the overall rigidity of the junction between the base slab and the side wall by enhancing the stability of the brick formwork.

[0036] The support unit 20 is located on the outside of the brick formwork unit 10, that is, between the brick formwork unit 10 and the shotcrete slope protection 50, and is configured in... Figure 1 On the left side of the brick formwork, it is mainly used to resist the lateral pressure of concrete and connects with the shotcrete slope protection 50. Secondary square steel bars 21 are arranged horizontally along the brick formwork unit 10, and primary square steel bars 22 are arranged vertically along the brick formwork unit 10. Several secondary square steel bars 21 are evenly distributed along the height of the first step brick formwork 11, and are set close to the wall surface of the brick formwork. Several primary square steel bars 22 are arranged vertically side by side, forming a cross-vertically arranged support network with the secondary square steel bars 21. The secondary square steel bars 21 and primary square steel bars 22 can be welded together or connected by wire wrapping. All secondary square steel bars 21 and primary square steel bars 22 are 40mm square steel bars, with a spacing of 300mm between adjacent secondary square steel bars 21 and a spacing of 1200mm between adjacent primary square steel bars 22.

[0037] The support unit 20 also includes several horizontally arranged circular steel pipes 23, each with an adjustable top support 24 at one end. This adjustable top support can directly lock and abut against the outer wall of the main square steel rib 22, thereby supporting the brick formwork. The other end of the circular steel pipe 23 is inserted into a pre-embedded sleeve 51 pre-installed in the shotcrete slope protection 50, achieving a reliable connection with the shotcrete slope protection 50. Its core function is to ultimately transfer and unload the enormous lateral pressure generated during concrete pouring onto the stable shotcrete slope protection 50.

[0038] The shotcrete and anchor slope protection 50 is an inclined structure. A horizontally embedded sleeve 51 is pre-embedded within the shotcrete and anchor slope protection 50. The end of the steel pipe 23 furthest from the adjustable top support 24 is inserted into the embedded sleeve 51, indirectly entering the shotcrete and anchor slope protection 50. The diameter of the embedded sleeve 51 is 2-5 mm larger than the diameter of the steel pipe 23. A wooden board 52 is placed between the embedded sleeve 51 and the shotcrete and anchor slope protection 50.

[0039] like Figure 2As shown, a steel mesh composed of slope protection steel bars 53 is provided outside the sprayed anchor slope protection 50. The wooden board 52 is 150mm×150mm in size and is not connected to the slope protection steel bars 53.

[0040] The support unit 20 integrates the originally independent brick formwork with the robust shotcrete and anchor slope protection 50 (foundation pit slope protection structure), using the slope protection as an anchor support to form a stable support system, greatly improving overall stability. By tightening the adjustable top support 24, a clamping force can be applied to the main square steel 22, ensuring that the entire support unit 20 is in a "taut" state before concrete pouring, enabling it to more proactively and effectively resist subsequent pressure. The adjustable top support 24 is a length-adjustable structure, allowing construction personnel to fine-tune the support length to compensate for construction errors, such as uneven slope surfaces or deviations in brick formwork masonry, ensuring that each steel pipe 23 tightly and effectively transmits pressure. The pre-embedded sleeve 51 provides standardized connection points, facilitating the quick insertion and removal of the steel pipe 23 and allowing for slight displacement to accommodate minor deformations; moreover, all pressure is ultimately borne by the robust slope protection, avoiding the risk of the support system becoming unstable within the pit.

[0041] Waterproof unit 30 is installed inside the brick formwork unit 10, that is, installed as shown in the example. Figure 1 On the right side, there are waterproof mortar finishing layer 32 and waterproof membrane layer 31. The waterproof mortar finishing layer 32 is applied to the inner side of the brick formwork unit 10, i.e., located as shown in the image. Figure 1 The first brick formwork unit 10 is located on the right side and intersects with the cushion layer 40. The cushion layer 40 is a cement layer placed on the base 60, formed by pouring cement after the slope protection reinforcement is laid and intersected with the base 60. The waterproof membrane layer 31 is laid on top of the waterproof mortar plaster layer 32, that is, the waterproof mortar plaster layer 32 is placed tightly against the first brick formwork 11. The waterproof membrane layer 31 is placed on the side of the waterproof mortar plaster layer 32 away from the brick formwork, that is, on its outer wall surface. The upper end of the waterproof membrane layer 31 is turned up to the top of the first brick formwork 11. A plastic sheet 33 is laid between the waterproof membrane layer 31 and the second brick formwork 12 to protect the waterproof membrane layer 31 from damage during removal. The use of the waterproof mortar plaster layer 32 and the waterproof membrane layer 31 can achieve a double waterproof structure. The waterproof membrane layer 31 is turned up and overlaps with the subsequent wall waterproof membrane to form a continuous waterproof barrier.

[0042] A plastic sheet 33 is placed above the waterproof membrane layer 31, and the second-step brick formwork 12 covers the plastic sheet 33. The plastic sheet 33 makes the second-step brick formwork 12 easy to remove, preventing damage to the waterproof membrane layer 31 and improving construction efficiency and material utilization. The waterproof membrane layer 31 requires rigid protection to prevent damage during subsequent construction (such as rebar tying and concrete pouring); however, the second-step brick formwork 12, as a protective layer, itself needs to be removed in subsequent processes; if bricks are directly laid on the waterproof membrane layer 31, removal will inevitably tear and damage the expensive waterproof layer. Therefore, the plastic sheet 33 is introduced as an inexpensive, smooth, and flexible physical isolation layer. The plastic sheet 33 acts like an isolation membrane, inserted between the protective bricks (second-step brick formwork 12) and the waterproof membrane layer 31, which require a tight bond, fundamentally changing their bonding relationship. The second-step brick formwork 12 provides rigid physical protection, resisting impacts and loads, ensuring the absolute safety of the waterproof membrane layer 31 during the construction of the base slab. This structural design achieves rigid integration during protection and easy separation during removal; that is, during construction, the second-step brick formwork 12 provides rigid protection for the waterproof membrane layer 31; during removal, due to the isolation effect of the plastic sheet 33, the bricks will separate from the plastic sheet with just a gentle pry, thus ensuring that the waterproof membrane layer remains intact.

[0043] This application uses a horizontally set steel pipe 23 as a thrust rod and an adjustable top support 24 to achieve precise clamping, so as to horizontally transfer and unload the lateral pressure borne by the brick formwork to the sprayed and anchored slope protection 50 on the side wall of the foundation pit, thereby solving the problem of huge lateral pressure of thick bottom slab concrete in the most direct and stable way.

[0044] A method for constructing side formwork for a thick basement slab, using the side formwork device described above, includes the following steps:

[0045] S1. Construct the first step brick formwork 11 according to the thickness of the base slab, that is, construct the first step brick formwork 11 with the same height as the base slab to build the base slab outline. This base slab outline is the base slab skeleton and permanent template of the entire side formwork, providing an installation benchmark for all subsequent components.

[0046] S2. Install the secondary square steel 21, main square steel 22, steel pipe 23, and adjustable top support 24 from the support unit 20 on the left outer side of the first-step brick formwork 11. Arrange the secondary square steel 21 and main square steel 22 alternately on the outer layer of the first-step brick formwork 11, and support the main square steel 22 with the adjustable top support 24. In the support unit 20, the steel pipe 23 is connected to the sprayed and anchored slope protection 50 through a pre-embedded sleeve 51, and a wooden board 52 is placed at the connection between the steel pipe 23 and the sprayed and anchored slope protection 50, but it is not connected to the slope protection reinforcement 53. The purpose of this step is to establish active support, that is, to install a support system composed of square steel (secondary and main ribs), steel pipe, and adjustable top support on the outer side of the brick formwork. This system is key to resisting the lateral pressure of concrete, forming a pre-tightened rigid support frame connected to the sprayed and anchored slope protection 50 before concrete pouring, transferring the lateral load to the ground.

[0047] S3. Apply a waterproof mortar finish 32 to the inside of the first-step brick formwork 11, then lay a waterproof membrane layer 31 and turn it upwards to form a waterproof unit 30. A section of the waterproof membrane layer 31 is left at the top of the first-step brick formwork 11 to overlap with the subsequent wall waterproof membrane, forming a continuous waterproof unit 30. The purpose is to construct a continuous, double-layered flexible waterproof barrier at the base of the structure, which is a core step in resolving potential leakage problems.

[0048] S4. Lay a plastic sheet 33 on the waterproof membrane layer 31, and then build the second brick formwork 12 on the plastic sheet 33. This forms a separable protective layer, which provides rigid protection for the fragile waterproof layer during construction and also leaves room for subsequent non-destructive removal.

[0049] S5. Install the slope protection reinforcement 53, then pour concrete and proceed with the main structure construction. After all the aforementioned measures are in place, the enormous lateral pressure of the thick base slab concrete has been reliably resisted, and the underlying waterproof layer has been properly protected.

[0050] S6. After the concrete hardens, remove support unit 20. Support unit 20 (square steel, steel pipe, top support) are all reusable materials for future reuse to reduce costs.

[0051] The specific technical effects of this construction method are reflected in the following aspects:

[0052] Reliable lateral pressure resistance: The support system in S2 and the bottom slab structure outline in S1 can be completed simultaneously, forming an active protection of first supporting and then pouring, effectively preventing the brick formwork from cracking and deforming under concrete pressure.

[0053] High waterproof reliability: The waterproof unit 30 structure in S3 is formed in one go before the main construction. The waterproof membrane is turned up to ensure a seamless overlap between the bottom plate and the side wall waterproof layer, eliminating leakage channels at the junction from the root.

[0054] High construction efficiency and material utilization: The design in S4 makes the removal of the second-step brick formwork 12 quick and without damage, greatly improving work efficiency and protecting the expensive waterproof membrane 100%; the plastic sheet 33 avoids unnecessary damage to the waterproof membrane and improves material utilization.

[0055] Good operability and economy: The construction of each unit can be organized into a continuous operation, which is convenient and safe. The components of the support unit 20 in S6 can be reused after dismantling, which reduces production costs and is environmentally friendly.

[0056] This application discloses a basement thick floor slab side formwork device. By combining brick formwork units with support units, it significantly improves the overall rigidity and lateral pressure resistance of the side formwork, effectively preventing cracking of the brick formwork and thus enhancing the structural stability at the junction of the floor slab and side walls. Furthermore, by replacing ordinary plaster with waterproof mortar and forming a double waterproof layer with the upturned waterproof membrane, the continuity and reliability of the waterproof structure are achieved, greatly improving the overall waterproofing effect of the basement. Simultaneously, by placing plastic sheeting between the waterproof membrane and the second-stage brick formwork, both hard protection of the waterproof unit is achieved, facilitating subsequent removal and construction, preventing damage to the waterproof membrane layer, and improving construction efficiency and material utilization. In addition, the support unit achieves a detachable connection with the sprayed and anchored slope protection through adjustable top supports and pre-embedded sleeves. This not only ensures stable installation but also allows for reuse, reducing construction costs and embodying the concept of green construction. This application can ensure construction quality while also being economical, operable, and durable, and is applicable to various large basements, especially civil defense basement projects. This application also proposes a construction method for basement thick floor slab side formwork using this device.

[0057] The embodiments of this application have been described in detail above. These descriptions are merely preferred embodiments and should not be construed as limiting the scope of this application. All equivalent variations and modifications made within the scope of this application should still fall within the patent coverage of this application.

Claims

1. A side formwork device for a thick basement floor slab, characterized in that, include: The brick formwork unit is built along the side of the base plate, and its height is adapted to the thickness of the base plate. It includes the first step brick formwork and the second step brick formwork stacked together. A support unit is set on the outside of the brick formwork unit to resist the lateral pressure of the concrete and to connect with the shotcrete slope protection. A waterproof unit is set inside the brick formwork unit, including a waterproof mortar plastering layer and a waterproof membrane layer; a plastic sheet is also provided above the waterproof membrane layer, and the second brick formwork covers the plastic sheet.

2. The basement thick floor slab side formwork device according to claim 1, characterized in that, The first step of the brick formwork is laid to the same height as the base slab thickness, and the second step of the brick formwork is laid to the height of one brick layer, which is used to cover and protect the waterproof membrane layer.

3. A side formwork device for a thick basement slab according to claim 1 or 2, characterized in that, The support unit includes: The secondary rib square steel, the main rib square steel, the steel pipe, and the adjustable top support are arranged on the outside of the brick membrane unit. The secondary rib square steel is arranged horizontally along the brick membrane unit, and the main rib square steel is arranged vertically along the brick membrane unit. One end of the steel pipe is provided with the adjustable top support to support the main rib square steel, and the other end is connected to the shotcrete and anchor slope protection.

4. A basement thick floor slab side formwork device according to claim 3, characterized in that, Both the secondary rib square steel and the primary rib square steel are 40mm square steel, the spacing between adjacent secondary rib square steel is 300mm, and the spacing between adjacent primary rib square steel is 1200mm.

5. A side formwork device for a thick basement slab according to claim 3, characterized in that, A horizontally embedded sleeve is pre-embedded in the shotcrete and anchor slope protection, and the steel pipe is inserted into the shotcrete and anchor slope protection through the embedded sleeve; wherein, the diameter of the embedded sleeve is 2-5mm larger than the diameter of the steel pipe.

6. A side formwork device for a thick basement slab according to claim 5, characterized in that, A wooden board is placed between the pre-embedded sleeve and the sprayed anchor slope protection; a slope protection steel bar is provided at the middle position of the thickness of the sprayed anchor slope protection, which is not connected to the wooden board.

7. A side formwork device for a thick basement slab according to any one of claims 4-6, characterized in that, In the waterproof unit, the waterproof mortar plastering layer is applied to the inside of the brick formwork unit and intersects with the padding layer; the waterproof membrane layer is laid on the waterproof mortar plastering layer and turned up to the top of the first step brick formwork.

8. A basement thick floor slab side formwork device according to claim 7, characterized in that, The plastic sheet is laid between the waterproof membrane layer and the second step brick formwork to protect the waterproof membrane layer from damage during removal.

9. A method for constructing side formwork for a thick basement slab, characterized in that, The side mold device as described in claims 1-8 includes the following steps: S1. Lay the first brick formwork according to the thickness of the base plate; S2. Install the secondary rib square steel, main rib square steel, steel pipe and adjustable top support in the support unit on the outside of the first step brick formwork, so that the secondary rib square steel and the main rib square steel are arranged crosswise on the outer layer of the first step brick formwork, and the main rib square steel is supported by the adjustable top support. S3. Apply a waterproof mortar plaster layer to the inside of the brick formwork in the first step, lay the waterproof membrane layer and turn it up to form a waterproof unit. S4. Lay the plastic sheet on the waterproof membrane layer, and then build the second step brickwork on the plastic sheet; S5. Install the slope protection reinforcement bars, and then pour the concrete. S6. After the concrete hardens, remove the support unit for future reuse.

10. A method for constructing side formwork for a thick basement slab according to claim 9, characterized in that, In the support unit, the steel pipe is connected to the sprayed and anchored slope protection through a pre-embedded sleeve, and a wooden board is placed at the connection between the steel pipe and the sprayed and anchored slope protection, but it is not connected to the slope protection reinforcement; a section of the waterproof membrane layer is reserved on the top of the first step brick formwork, which overlaps with the subsequent wall waterproof membrane layer to form a continuous waterproof unit.

Images