Construction method of shaft lining annular turnover form structure

Abstract

The application relates to the technical field of tunnel shield construction, in particular to a vertical shaft lining annular turnover formwork structure construction method, which comprises a vertical shaft, an anchor rod is fixedly installed on the inner wall of the vertical shaft, an annular formwork support is supported on the anchor rod, two lining concretes are poured between the inner wall of the vertical shaft and the annular formwork support, the annular formwork support comprises a support truss, a horizontal rod, a vertical rod and a concrete formwork, and the vertical rod can be distributed on the annular formwork support at the optimal interval through the horizontal interval control of the vertical rod, so that the material is not wasted, and the stability and safety of the annular formwork support structure are guaranteed.

Description

Technical Field

[0001] This invention relates to the field of tunnel shield construction technology, and more specifically, to a construction method for a ring-shaped formwork structure for the inner lining of a vertical shaft. Background Technology

[0002] When constructing shield tunnels, secondary lining is often required from the bottom up to reinforce deep tunnel shafts with poor geological conditions. Traditional scaffolding erection occupies a significant amount of internal shaft space, affecting other construction processes, and dismantling the scaffolding is time-consuming, severely wasting the construction period. Therefore, we propose a construction method using a ring-shaped formwork structure for the shaft lining. This method utilizes a ring-shaped formwork support to leave a large space in the middle of the shaft, thus not affecting the construction period. This method requires precise calculation and definition of the structural parameters of the ring-shaped formwork support under various factors such as different shaft radii, surrounding rock conditions, and different secondary lining thicknesses to ensure that materials are not wasted while guaranteeing the stability and safety of the ring-shaped formwork support structure. Summary of the Invention

[0003] The purpose of this invention is to provide a construction method for a ring-shaped formwork structure for a vertical shaft lining. Under various factors such as different vertical shaft radii, surrounding rock conditions, and different secondary lining thicknesses, it is necessary to accurately calculate and define the structural parameters of the ring-shaped formwork support to ensure that materials are not wasted while guaranteeing the stability and safety of the ring-shaped formwork support structure.

[0004] The purpose of this invention is to provide a construction method for a ring-shaped formwork structure for a vertical shaft lining. The method includes a vertical shaft, with anchor rods fixedly installed on its inner wall. A ring-shaped formwork support is supported on the anchor rods. Secondary lining concrete is poured between the inner wall of the vertical shaft and the ring-shaped formwork support. The ring-shaped formwork support includes a supporting truss, horizontal bars, vertical bars, and a concrete formwork. The horizontal bars are fixedly connected to the surface of the supporting truss using bolts. The vertical bars are fixedly connected to the surface of the horizontal bars using bolts. The concrete formwork is fixedly connected to the side of the vertical bars away from the supporting truss. The formula for controlling the horizontal spacing of the vertical bars is as follows.

[0005]

[0006] In Equation 1, m is the spacing between the uprights.

[0007] h is the height of a single section of the inner mold.

[0008] γ is the unit weight of the cast-in-place material.

[0009] α is the lateral pressure coefficient of the cast-in-place structure.

[0010] P represents the uniformly distributed live load during construction on the upper surface of the cast-in-place structure.

[0011] f is the design value of the bending strength of the upright.

[0012] W is the section modulus of the upright.

[0013] k Δ The bending moment coefficient under uniformly distributed load is...

[0014] k is the bending moment coefficient under triangular distributed load.

[0015] h / n represents the spacing of the horizontal bars, which are evenly distributed vertically.

[0016] Preferably, the formula for the bending moment value generated by the dead load on the upright section is as follows:

[0017]

[0018] In Equation 2, M Δ The bending moment value generated by the cross section of the upright.

[0019] m is the spacing between the uprights.

[0020] h is the height of a single section of the inner mold.

[0021] γ is the unit weight of the cast-in-place material.

[0022] α is the lateral pressure coefficient of the cast-in-place structure.

[0023] k Δ The bending moment coefficient under uniformly distributed load is...

[0024] h / n represents the spacing of the horizontal bars, which are evenly distributed vertically.

[0025] Preferably, the formula for the bending moment value generated by the live load on the upright section is as follows:

[0026]

[0027] In Equation 3, M0 is the bending moment generated by the cross section of the upright.

[0028] m is the spacing between the uprights.

[0029] α is the lateral pressure coefficient of the cast-in-place structure.

[0030] P represents the uniformly distributed live load during construction on the upper surface of the cast-in-place structure.

[0031] k is the bending moment coefficient under triangular distributed load.

[0032] h / n represents the spacing of the horizontal bars, which are evenly distributed vertically.

[0033] Preferably, the combined design formula for the pole load is as follows:

[0034] M = 1.3MΔ +1.5M0 (Equation 4)

[0035] In Equation 4, M represents the total strength of the load on the annular formwork support.

[0036] M Δ The bending moment generated by the dead load on the cross section of the pole.

[0037] M0 is the bending moment generated by live load on the cross section of the upright.

[0038] Preferably, the formula for calculating the bending strength of the upright is as follows:

[0039]

[0040] In Equation 5, f is the design value of the bending strength of the upright.

[0041] W is the section modulus of the upright.

[0042] M represents the total strength of the pole load.

[0043] Preferably, the annular formwork support has multiple layers, with the bottom annular formwork support continuously flipping over to the top annular formwork support. The crossbar is arc-shaped, and the concrete formwork is arc-shaped.

[0044] Preferably, the two sides of the upright are bent at ninety degrees, the upright is in a U-shape, and the uprights are evenly distributed in a ring on the side of the crossbar away from the supporting truss.

[0045] This invention provides a construction method for a ring-shaped formwork structure for a vertical shaft lining. The method includes a vertical shaft, with anchor rods fixedly installed on its inner wall. A ring-shaped formwork support is mounted on the anchor rods. Secondary lining concrete is poured between the inner wall of the shaft and the ring-shaped formwork support. The ring-shaped formwork support includes a supporting truss, horizontal bars, vertical bars, and a concrete formwork. The horizontal bars are fixedly connected to the surface of the supporting truss using bolts. The vertical bars are fixedly connected to the surface of the horizontal bars using bolts. The concrete formwork is fixedly connected to the side of the vertical bars away from the supporting truss. The horizontal spacing of the vertical bars is controlled using the following formula.

[0046]

[0047] By controlling the horizontal spacing of the uprights, the uprights can be distributed on the ring formwork support at the optimal spacing, which not only avoids wasting materials but also ensures the stability and safety of the ring formwork support structure. Attached Figure Description

[0048] Figure 1 A side view of the annular formwork support for a construction method of an annular formwork structure for a vertical shaft lining provided in an embodiment of the present invention;

[0049] Figure 2 A plan view of the annular formwork support for a construction method of an annular formwork structure for a vertical shaft lining provided in an embodiment of the present invention;

[0050] Figure 3 A top view of the annular formwork support inside the shaft, which is part of a construction method for annular formwork structure for shaft lining provided in an embodiment of the present invention.

[0051] Figure 4 A frontal perspective three-dimensional schematic diagram of the annular formwork support structure for a construction method of an annular formwork structure for a vertical shaft lining provided in an embodiment of the present invention;

[0052] Figure 5 A concrete pouring load diagram for a construction method of a vertical shaft lining annular formwork structure provided in an embodiment of the present invention;

[0053] Figure 6 The concrete construction load diagram is provided for a method of constructing a vertical shaft lining annular formwork structure according to an embodiment of the present invention.

[0054] In the diagram: 11. Shaft; 12. Circular formwork support; 13. Secondary lining concrete; 14. Anchor bolt; 21. Support truss; 22. Horizontal bar; 23. Vertical bar; 24. Concrete formwork. Detailed Implementation

[0055] This invention provides a construction method for a ring-shaped formwork structure for a vertical shaft lining, comprising a vertical shaft 11, with anchor rods 14 fixedly installed on the inner wall of the shaft 11. A ring-shaped formwork support 12 is supported on the anchor rods 14. Secondary lining concrete 13 is poured between the inner wall of the shaft 11 and the ring-shaped formwork support 12. The ring-shaped formwork support 12 includes a supporting truss 21, horizontal bars 22, vertical bars 23, and a concrete formwork 24. The horizontal bars are fixedly connected to the surface of the supporting truss by bolts, and the vertical bars are fixed to the surface of the horizontal bars by bolts. The concrete formwork is fixedly connected to the side of the vertical bars away from the supporting truss. The inner wall of the shaft 11 is the initial lining concrete. The secondary lining concrete 13 is poured by continuously turning the bottom layer of secondary lining concrete 13 onto the top layer. The horizontal spacing control requirements of the vertical bars 23 are as follows:

[0056]

[0057] In Equation 1, m is the spacing between the uprights.

[0058] h is the height of a single section of the inner mold.

[0059] γ is the unit weight of the cast-in-place material.

[0060] α is the lateral pressure coefficient of the cast-in-place structure.

[0061] P0 is the uniformly distributed live load on the upper surface of the cast-in-place structure during construction.

[0062] f is the design value of the bending strength of the upright.

[0063] W0 is the section modulus of the upright.

[0064] k Δ The bending moment coefficient under uniformly distributed load is...

[0065] k0 is the bending moment coefficient under triangular distributed load.

[0066] h / n is the spacing of the horizontal bars that are evenly distributed vertically.

[0067] The distribution of the horizontal spacing of the uprights 23 directly affects the overall structural strength of the ring formwork support 12. It is necessary to calculate the optimal horizontal spacing of the uprights 23 based on the total load force borne by the ring formwork support 12. The optimal spacing of the uprights 23 can ensure that materials are not wasted while guaranteeing the stability and safety of the ring formwork support 12 structure.

[0068] The formula for the bending moment generated by the dead load at section 23 of the upright is as follows.

[0069]

[0070] In Equation 2, M Δ This represents the bending moment generated at section 23 of the upright.

[0071] m is the spacing between the uprights.

[0072] h is the height of a single section of the inner mold.

[0073] γ is the unit weight of the cast-in-place material.

[0074] α is the lateral pressure coefficient of the cast-in-place structure.

[0075] k Δ The bending moment coefficient under uniformly distributed load is...

[0076] h / n represents the spacing of the horizontal bars, which are evenly distributed vertically.

[0077] The formula for the bending moment generated by the live load at section 23 of the upright is as follows.

[0078]

[0079] In Equation 3, M0 is the bending moment generated by section 23 of the upright.

[0080] m is the spacing between the uprights.

[0081] α is the lateral pressure coefficient of the cast-in-place structure.

[0082] P0 is the uniformly distributed live load on the upper surface of the cast-in-place structure during construction.

[0083] k0 is the bending moment coefficient under triangular distributed load.

[0084] h / n is the spacing of the horizontal bars that are evenly distributed vertically.

[0085] k Δ Here, k is the bending moment coefficient under uniformly distributed load, and k0 is the bending moment coefficient under triangular distributed load, as shown in the table below:

[0086] 2 0.067 0.125 3 0.0778 0.100 4 0.0848 0.1071 5 0.089 0.1053 6 0.0918 0.1058 7 0.0938 0.1056 8 0.0952 0.1057

[0087] Therefore, it can be seen that as the number of loads increases, the bending moment coefficient k under uniformly distributed load increases. Δ Both the bending moment coefficient k0 under triangular distributed load and uniformly distributed load show a gradually increasing trend. Under the same load quantity, the bending moment coefficient k0 under triangular distributed load is always greater than that under uniformly distributed load. Δ This indicates that triangular distributed loads have a significant impact on the bending moment generated by the structure. As the amount of load increases, the bending moment coefficient k under uniformly distributed loads decreases. Δ The increase in the bending moment coefficient k0 under triangular distributed load gradually decreases. This indicates that, within a certain range, the effect of increasing the amount of load on the bending moment coefficient gradually weakens.

[0088] The combined design formula for the load on pole 23 is as follows.

[0089] M = 1.3M Δ +1.5M0 (Equation 4)

[0090] In Equation 4, M represents the total strength of the load on the annular formwork support 12.

[0091] M Δ The bending moment generated by the dead load on the cross section of the pole.

[0092] M0 is the bending moment generated by live load on the cross section of the upright.

[0093] By calculating the total strength of the load on the ring formwork support 12, the stability and safety of the support under various load conditions can be ensured. This helps prevent accidents during construction, ensures the smooth progress of the project, optimizes the design, saves materials, ensures construction efficiency, and guarantees the best overall solution for the ring formwork support 12.

[0094] The formula for calculating the bending strength of pole 23 is as follows.

[0095]

[0096] In Equation 5, f is the design value of the bending strength of the upright.

[0097] W0 is the section modulus of the upright.

[0098] M represents the total strength of the load on pole 23.

[0099] Verifying the bending strength of the ring formwork support 12 is crucial for ensuring construction safety, optimizing design, reducing costs, improving construction efficiency, and complying with regulations. This helps improve the performance of the ring formwork support 12, reduce project risks, and create favorable conditions for the successful completion of the project.

[0100] The ring formwork support 12 has multiple layers. The bottom ring formwork support 12 will be continuously flipped over to the top ring formwork support 12. The flipping process can only be carried out after the secondary lining concrete 13 between the bottom ring formwork support 12 and the inner wall of the shaft 11 has solidified.

[0101] Among them, the two sides of the upright 23 are bent at ninety degrees, and the upright 23 is in the shape of "U". The upright 23 is evenly distributed in a ring on the side of the horizontal bar 22 away from the supporting truss 21. The spacing of the upright 23 on the horizontal bar 22 can determine the overall strength of the ring formwork support 12. The installation spacing of the upright 23 should be adapted to the environment inside the shaft 11 to achieve the optimal arrangement.

[0102] Working principle: First, define the horizontal spacing of the uprights as m, the height of a single section of the inner mold as h, and the horizontal bars as being evenly distributed vertically with a spacing of h / n; the unit weight of the cast-in-place body is γ, the lateral pressure coefficient of the cast-in-place body is α, the uniformly distributed live load on the upper surface of the cast-in-place body is P0, the design value of the bending strength of the uprights is f, and the section modulus of the uprights is W0, k Δ Let k be the bending moment coefficient under uniformly distributed load, and k0 be the bending moment under triangular distributed load. The bending moment value generated by the dead load on the upright section is then obtained.

[0103]

[0104] The bending moment generated by the live load on the upright section:

[0105]

[0106] The bending moment value generated by the dead load on section 23 of the upright and the bending moment value generated by the live load on section 23 of the upright are combined to obtain the result.

[0107] M = 1.3M Δ +1.5M0 (Equation 4)

[0108] To ensure the bending strength of the uprights meets the requirements, verify the following formula:

[0109]

[0110] At this point, the horizontal spacing control requirements for the uprights can be determined:

[0111]

[0112] By controlling the horizontal spacing of the uprights 23, the uprights 23 can be distributed on the annular formwork support 12 at the optimal spacing, which not only avoids wasting materials but also ensures the stability and safety of the annular formwork support 12 structure.

Claims

1. A construction method for a ring-shaped formwork structure for the lining of a vertical shaft, characterized in that: The structure includes a vertical shaft, on the inner wall of which anchor bolts are fixedly installed. A ring-shaped formwork support is mounted on the anchor bolts. Secondary lining concrete is poured between the inner wall of the shaft and the ring-shaped formwork support. The ring-shaped formwork support includes a supporting truss, horizontal bars, vertical bars, and concrete formwork. The horizontal bars are fixedly connected to the surface of the supporting truss using bolts. The vertical bars are fixedly connected to the surface of the horizontal bars using bolts. The concrete formwork is fixedly connected to the side of the vertical bars away from the supporting truss. The formula for controlling the horizontal spacing of the vertical bars is as follows. (Equation 1) In Equation 1, m is the spacing between the uprights. h is the height of a single section of the inner mold. γ is the unit weight of the cast-in-place material. α is the lateral pressure coefficient of the cast-in-place structure. P0 is the uniformly distributed live load on the upper surface of the cast-in-place structure during construction. f is the design value of the bending strength of the upright. W0 is the section modulus of the upright. k Δ The bending moment coefficient under uniformly distributed load is... K0 is the bending moment coefficient under triangular distributed load. h / n represents the spacing of the horizontal bars, which are evenly distributed vertically.

2. The construction method for a vertical shaft lining annular formwork structure as described in claim 1, characterized in that: The formula for the bending moment value generated by the dead load on the upright section is as follows. (Equation 2) In Equation 2, The bending moment value generated by the cross section of the upright. m is the spacing between the uprights. h is the height of a single section of the inner mold. γ is the unit weight of the cast-in-place material. α is the lateral pressure coefficient of the cast-in-place structure. k Δ The bending moment coefficient under uniformly distributed load is... h / n represents the spacing of the horizontal bars, which are evenly distributed vertically.

3. The construction method for a vertical shaft lining annular formwork structure as described in claim 2, characterized in that: The formula for the bending moment value generated by the live load on the upright section is as follows. (Equation 3) In Equation 3, The bending moment value generated by the cross section of the upright. m is the spacing between the uprights. α is the lateral pressure coefficient of the cast-in-place structure. P0 is the uniformly distributed live load on the upper surface of the cast-in-place structure during construction. K0 is the bending moment coefficient under triangular distributed load. h / n represents the spacing of the horizontal bars, which are evenly distributed vertically.

4. The construction method for a vertical shaft lining annular formwork structure as described in claim 3, characterized in that: The combined design formula for the pole load is as follows. (Equation 4) In Equation 4, The total strength of the load on the ring-shaped formwork support. The bending moment generated by the dead load on the cross section of the pole. The bending moment generated by live load on the cross section of the pole.

5. The construction method for a vertical shaft lining annular formwork structure as described in claim 4, characterized in that: The formula for calculating the bending strength of the upright is as follows: (Equation 5) In Equation 5, f is the design value of the bending strength of the upright. W0 is the section modulus of the upright. This represents the total strength of the pole load.

6. The construction method for a vertical shaft lining annular formwork structure as described in claim 1, characterized in that: The annular formwork support has multiple layers. The bottom annular formwork support will continuously flip over to the top annular formwork support. The crossbar is arc-shaped, and the concrete formwork is arc-shaped.

7. The construction method for a vertical shaft lining annular formwork structure as described in claim 6, characterized in that: The uprights are bent at ninety degrees on both sides, and the uprights are in a U-shape. The uprights are evenly distributed in a ring on the side of the crossbar away from the supporting truss.

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