Construction method of formwork device suitable for vertical shaft

Abstract

The invention relates to a construction method of a formwork device suitable for a vertical shaft. The method comprises the following steps that the vertical shaft is excavated, a blade angle is spliced at the bottom of the vertical shaft after the ground is hardened, and vertical shaft pipe pieces are assembled on the upper portion of the blade angle; the outer side of the blade angle is used as a fore shaft ring beam pouring area, and a plurality of annular protection blocks are arranged on the side portion between the area and the vertical shaft duct piece; and the formworks are sequentially inserted into the gap between the fore shaft ring beam pouring area and the vertical shaft duct piece. Compared with the prior art, the pouring formwork is easy to install, good in formwork leakage stopping effect and convenient to disassemble, the surface of poured concrete is smoother, and good economic value is achieved. The concrete protection layer supporting block is of a circular ring structure, in the process that a formwork is installed from top to bottom, the annular protection block can roll around the axis steel bar, and the friction effect on the formwork is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of shaft construction, and particularly relates to a construction method of a formwork device suitable for a shaft. Background Art

[0002] The shaft project is an important construction method in modern foundation pit engineering. Before the suspension-type shaft construction sinks, it is necessary to first excavate a certain height of foundation pit, then place the steel cutting edge angle and the first layer of shaft segments, and then pour a ring of concrete beam around the periphery of the segments and the cutting edge angle, which is called the collar beam. Due to the narrow construction site of the collar beam, it is difficult to overlap the formwork by conventional methods, and it is also difficult to adopt the conventional formwork removal method during the formwork removal process. Therefore, a formwork suitable for the concrete pouring of the shaft collar beam and its construction method are designed. Summary of the Invention

[0003] In order to overcome the above problems existing in the prior art, the invention provides a construction method of a formwork device suitable for a shaft, which is used to solve the above problems existing in the prior art.

[0004] A construction method of a formwork device suitable for a shaft, the method adopts the following steps:

[0005] S1. Excavate the shaft, splice the cutting edge angle at the bottom of the shaft after hardening the ground, and assemble the shaft segments on the upper part of the cutting edge angle;

[0006] S2. Take the outside of the cutting edge angle as the pouring area of the collar beam, and support blocks are arranged on the side between this area and the shaft segments;

[0007] S3. Insert the formwork into the gap between the pouring area of the collar beam and the shaft segments in sequence.

[0008] In the above aspect and any possible implementation manner, a further implementation manner is provided. The formwork is provided with several pieces, and both ends of the length of each piece are set as insert-type chamfer shapes. The chamfer side length is longer on the side close to the pouring area of the collar beam, and the chamfer side is shorter on the side close to the shaft segments.

[0009] In the above aspect and any possible implementation manner, a further implementation manner is provided. The cutting edge angle is spliced at the bottom of the pouring area of the collar beam, the shaft segments are arranged on the upper part of the cutting edge angle, and a gap is arranged between the pouring area of the collar beam and the shaft segments.

[0010] In the above aspect and any possible implementation manner, a further implementation manner is provided. Before S3, seal the long side of the insert-type chamfer of each formwork.

[0011] For the aspects and any possible implementation manners described above, a further implementation manner is provided, where the template is an extruded board.

[0012] For the aspects and any possible implementation manners described above, a further implementation manner is provided, where the height of the template is greater than the height of the lock - mouth ring beam.

[0013] For the aspects and any possible implementation manners described above, a further implementation manner is provided, where the support blocks are arranged at intervals in a ring shape on the pouring area of the lock - mouth ring beam of the gap.

[0014] For the aspects and any possible implementation manners described above, a further implementation manner is provided, where the support blocks are annular and several of them are provided.

[0015] For the aspects and any possible implementation manners described above, a further implementation manner is provided, where the annular support block includes a circular - ring concrete protection layer support block and the main reinforcement bars on the outer side of the lock - mouth ring beam, and the main reinforcement bars are inserted into the circular - ring concrete protection layer support block.

[0016] For the aspects and any possible implementation manners described above, a further implementation manner is provided, where the extruded board is a rigid foam plastic board formed by heating and extrusion.

[0017] For the aspects and any possible implementation manners described above, a further implementation manner is provided, where the rigid foam plastic board is a board with a closed - cell honeycomb structure made of polystyrene resin and other additives.

[0018] For the aspects and any possible implementation manners described above, a further implementation manner is provided, where the gap is 10 CM.

[0019] Advantages of the present invention

[0020] The construction method of the template device applicable to a shaft of the present invention adopts the following steps: excavate the shaft, splice the blade angle at the bottom of the shaft after hardening the ground, and assemble the shaft segments on the upper part of the blade angle; take the outer side of the blade angle as the pouring area of the lock - mouth ring beam, and support blocks are arranged on the side between this area and the shaft segments; insert the template successively into the gap between the pouring area of the lock - mouth ring beam and the shaft segments. Compared with the prior art, the pouring template provided by the present invention is simple to install, has good leak - proof effect of the template, is convenient to disassemble, the concrete surface is smoother after pouring, and has good economic value. The concrete protection layer support block provided by the present invention is of a circular - ring structure. During the process of installing the template from top to bottom, the annular support block can roll around the central reinforcing bar, reducing the frictional effect on the template. Description of the drawings

[0021] Figure 1It is a schematic sectional view of the template installation of the present invention;

[0022] Figure 2 It is a top view of the template installation of the present invention;

[0023] Figure 3 It is a top view of the lapping method of the template installation of the present invention;

[0024] Figure 4 It is a schematic diagram of the circular concrete protection block of the present invention;

[0025] Figure 5 It is a schematic diagram of the template installation process of the present invention. Specific embodiments

[0026] For a better understanding of the technical solution of the present invention, the content of the present invention includes but is not limited to the specific embodiments hereinafter, and similar technologies and methods should be regarded as within the scope of protection of the present invention. To make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments.

[0027] It should be clear that the embodiments described in the present invention are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative work shall fall within the scope of protection of the present invention.

[0028] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms of "a", "the" and "said" used in the embodiments of the present invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0029] As Figures 1-5 shown, the present invention provides a construction method for a template device applicable to a shaft, and the method adopts the following steps:

[0030] S1. Excavate the shaft, splice the blade angle at the bottom of the shaft after hardening the ground, and assemble the shaft segments above the blade angle;

[0031] S2. Take the outside of the blade angle as the casting area of the collar beam, and support blocks are arranged on the side between this area and the shaft segments;

[0032] S3. Insert the template into the gap between the casting area of the collar beam and the shaft segments in sequence.

[0033] The shaft segment 2, the cutting edge 3 and the collar beam are structural components of the shaft. Among them, the formwork 4 is the construction object required by the present invention and is used as a concrete pouring formwork. The collar beam is arranged on the outer part of the shaft segment 2, and anti-pulling piles are also arranged below the collar beam. The anti-pulling piles are connected to the collar beam. After the shaft construction is completed, the collar beam is cast and connected with the shaft wall. Therefore, the entire shaft wall, the collar beam and the anti-pulling piles form a whole, so that the engineering deformation is small. The shaft is a shaft wall structure formed by the construction method of sinking from top to bottom. The shaft is provided with a collar beam, and the cutting edge is inserted into the bottommost part of the shaft wall structure and is made of steel. It is provided with a tip to squeeze the soil during the sinking process. The shaft wall structure is realized by using the segment 2, which can be cast-in-place or precast. Therefore, the cutting edge 3 is arranged at the bottom of the collar beam concrete casting area or the collar beam casting area 1, and the shaft segment 2 is arranged on the top of the cutting edge 3. The two are in close contact connection, and there is a gap between the collar beam concrete casting area 1 and the shaft segment 2. The support blocks are arranged in a ring in the gap and are fixed on the collar beam concrete casting area 1, and the formwork 4 is arranged in the gap. During the shaft construction, there is a gap between the shaft wall and the collar beam. During the construction, lubricating mud is flushed into this gap, which can reduce the friction between the shaft wall and the outer soil and help with the sinking. However, this gap is very narrow, only about 10 cm. During the on-site construction, a launching pit is first excavated. The diameter of the launching pit should be larger than the diameter of the shaft. For example, if the diameter of the shaft is 20 m, the diameter of the launching pit should be 2 - 3 m larger than this diameter. This 2 - 3 m position is used to place the collar beam. During the construction, the cutting edge 3 is first assembled in the launching pit. Because the assembly of the cutting edge requires a certain space, the collar beam cannot be constructed at this time. After the construction of the cutting edge 3 is completed, the shaft wall at the topmost part of the cutting edge is constructed. The shaft wall is made of concrete, that is, the segment 2. The outer arc diameter of the cutting edge 3 is 10 cm larger than the outer arc of the shaft wall. This 10 cm is the gap mentioned above. After the construction of the cutting edge 3 and the segment 2 is completed, the collar beam is constructed. Since the collar beam is made of reinforced concrete, the cutting edge 3 made of steel directly serves as the support formwork during the pouring. However, the collar beam is made of reinforced concrete and the shaft wall is also made of concrete. Therefore, if the formwork 4 of the present invention is not arranged in the gap between the two, the collar beam and the shaft wall will be directly poured together. Therefore, a component for blocking the pouring between the two needs to be arranged in this gap, and after the pouring of each of the two is completed, this component should be easily removed or broken and eliminated. However, due to the small space of this gap in the project construction, after the construction inside the collar beam is completed, there is no space for the construction personnel to enter and construct the corresponding component.Therefore, the present invention uses a template as a component of this device, and the template 4 is arranged to be inserted from top to bottom, and is inserted by closely adhering to the shaft wall, and is fixed and inserted downward by means of the support blocks of the collar beam, so as to insert each template into this gap.

[0034] Further, the template 4 is realized by using an extruded sheet. The extruded sheet is a rigid foam plastic sheet formed by heating and extrusion. It is a sheet with a continuous and uniform surface layer and a closed-cell honeycomb structure manufactured by extruding polystyrene resin and other additives, which can insulate temperature and prevent concrete leakage during pouring. Before construction, the extruded sheet material is cut into cuboid materials of several widths according to the diameter of the shaft, and both sides are cut into insertable chamfer structures along the height direction. The chamfer length on the pouring side (i.e., the shaft wall side) is large, and the chamfer length on the other side is small, so as to prevent concrete from infiltrating during pouring.

[0035] Further, the height of the template is greater than the height of the collar beam, so as to prevent concrete from overflowing during pouring.

[0036] Further, the support blocks are arranged at a certain distance in the collar beam concrete casting area 1. The distance and quantity are set according to the height of the shaft, which is convenient for the subsequent insertion of the template 4. It includes an annular concrete protective layer support block 7 and the main reinforcement 8 on the outside of the collar beam. The main reinforcement 8 is inserted into the annular concrete protective layer support block 7. According to the diameter of the outside main reinforcement and the thickness of the protective layer, there can be different specifications of protective blocks, and annular protective blocks with different diameters are set according to the thickness of the protective layer. The thickness of the protective layer refers to the distance of the small part of the cushion layer above the annular concrete. The annular concrete protective layer refers to the part of the support block that protects the reinforcement 8 from being directly exposed, that is, the entire concrete layer from the outermost layer of the reinforcement 8 to the concrete surface of the annular concrete protective layer support block 7, which is the protective layer, and the thickness is about 5 cm. During construction, after the reinforcement 8 is tied, the cushion blocks are fixed on the reinforcement 8, and then wooden templates are made outside the cushion blocks. After pouring is completed, it is ensured that the outermost reinforcement will not be exposed outside the concrete. The cushion blocks used in the present invention are annular, and the reinforcement 8 passes through the middle ring. Therefore, the annular concrete protective layer support block 7 formed by the annular cushion blocks and the protective layer can rotate around the reinforcement 8 as the center. Therefore, when installing the template 4, only need to install and insert each template 4 from top to bottom. Each template 4 rolls on the cushion blocks of the support block and sinks in place with the help of the rolling action of the cushion blocks, that is, it contacts the top of the cutting edge 3. Therefore, the cushion blocks are set to be annular. If they are square or other shapes, etc., the insertion and installation of each template 4 will be difficult.

[0037] In the present invention, an extruded polystyrene board is used to replace the traditional concrete formwork. A material with good anti-permeability, good compressive performance, and relatively easy to be damaged is selected. Taking the extruded polystyrene board as an example, but it is not necessarily limited to the extruded polystyrene board.

[0038] Specifically, the construction process of the present invention is as follows: First, before the splicing of the shaft segments, an initial excavation pit with a certain height and a certain range is excavated. After hardening the ground, the steel cutting edge at the bottom of the shaft and the prefabricated shaft segments are spliced. The external main reinforcement of the collar beam is passed through the concrete circular protective block and then the steel bars are arranged. At the same time, the inner and outer sides of the prefabricated shaft segments are welded and fixed to the steel cutting edge at the bottom.

[0039] According to the perimeter of the shaft and the distance gap between the outer surface of the concrete and the shaft segment 2, the extruded polystyrene board is cut into a certain specification, and the two sides of the extruded polystyrene board are cut into an easy-to-insert chamfer structure. The chamfer side length on the side close to the pouring area is longer, and the chamfer side length on the side close to the segment 2 is shorter to prevent concrete leakage. According to the height of the shaft, as Figure 3 shown, the cut extruded polystyrene board can be two long strips spliced together to reach the required height.

[0040] The cut extruded polystyrene boards are inserted into the reserved formwork positions one by one from top to bottom. Due to the action of the circular concrete protective layer support blocks, when inserted, the extruded polystyrene boards roll down along the circular support blocks, and both sides are closely attached to the shaft segments and the support blocks, avoiding the movement of the formwork during the pouring process. Since the insertion position of the formwork is squeezed and fixed by the shaft segments and the circular protective blocks on both sides, the thickness of the formwork needs to be strictly controlled. If it is too thin, the formwork will be unstable; if it is too thick, it will be difficult to insert and install the formwork. The corresponding thickness is selected according to the actual situation of the construction site.

[0041] During splicing, since the formwork needs to be spliced into a circular shape, the sides close to the segments are squeezed against each other, so that the formwork is in direct and tight contact to prevent concrete leakage; in addition, close to the pouring area, since it is located on the outer side of the circular ring, the contact may not be very airtight, so a long-edge lap joint is set, and if necessary, the lap joint edge can be sealed in advance with solid glue to further prevent concrete leakage.

[0042] In addition, the formwork needs to be higher than the collar beam by a certain height after insertion to prevent concrete from overflowing during the pouring process. After all the formworks are installed, the concrete at the collar beam position is poured.

[0043] When removing the formwork, due to the inherent properties of the extruded polystyrene board, it is very easy to be damaged. Therefore, the extruded polystyrene board can be directly damaged into pieces with tools and then taken out.

[0044] The foregoing description has shown and described several preferred embodiments of the present invention. However, as previously mentioned, it should be understood that the present invention is not limited to the forms disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the above teachings or the skills or knowledge in the relevant field. Any alterations and changes made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the appended claims of the present invention.

Claims

1. A construction method of a formwork device applicable to a shaft, characterized in that, The method adopts the following steps: S1. Excavate a vertical shaft, splice the cutting edge angle at the bottom of the vertical shaft after hardening the ground, and assemble the segment of the vertical shaft above the cutting edge angle; S2. Take the outside of the cutting edge angle as the casting area of the collar beam, and support blocks are arranged on the side between this area and the segment of the vertical shaft; S3. Insert the formwork into the gap between the casting area of the collar beam and the segment of the vertical shaft in sequence.

2. The construction method according to claim 1, characterized in that, The formwork is provided with several pieces, and the two ends of the length of each piece are set in the shape of an inserted chamfer. The chamfer side length is longer on the side close to the casting area of the collar beam, and the chamfer side is shorter on the side close to the segment of the vertical shaft.

3. The construction method according to claim 1, characterized in that, The cutting edge angle is spliced at the bottom of the casting area of the collar beam, the segment of the vertical shaft is arranged above the cutting edge angle, and there is a gap between the casting area of the collar beam and the segment of the vertical shaft.

4. The construction method according to claim 2, characterized in that, Before S3, seal the long side of the inserted chamfer of each piece of formwork.

5. The construction method according to claim 1, characterized in that The formwork is an extruded polystyrene board.

6. The construction method according to claim 1, characterized in that, The height of the formwork is greater than the height of the collar beam.

7. The construction method according to claim 1, wherein The support blocks are annular and several are provided.

8. The construction method according to claim 7, characterized in that, Several of the support blocks are arranged at a certain distance on the casting area of the collar beam in the gap.

9. The construction method according to claim 7 or 8, characterized in that, The annular support block includes a circular concrete protective layer support block and the main reinforcement on the outside of the collar beam, and the main reinforcement is inserted into the circular concrete protective layer support block.

10. The construction method according to claim 5, characterized in that, The extruded polystyrene board is a rigid foam plastic board formed by heating and extrusion.

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