A tooling system and construction method for multi-layer inverted arch construction in salt rock tunnel strata

Abstract

A tooling system for the construction of multi-layer inverted arches in salt rock tunnel strata includes a fully enclosed template and a self-propelled long trestle. The fully enclosed template is provided with a head plate and an intermediate long template distributed along the axial direction of the tunnel. The intermediate long template is separated from the wall of the tunnel operation area by a preset distance. The fully enclosed template and the wall of the tunnel operation area enclose a concrete filling area, and the self-propelled long trestle is used to assist the movement of the intermediate long template. It can use the fully enclosed template for pouring, ensure the shape, size and construction quality of the pouring structure, especially the pouring of the water-proof structure, and meet the process and traffic organization requirements through the self-propelled long trestle.

Description

Technical Field

[0001] The invention relates to the technical field of tunnel construction, and in particular to a tooling system and a construction method for multi-layer inverted arch construction in a salt rock tunnel stratum. Background Art

[0002] During the construction of the Friendship Tunnel of the China-Laos Railway, salt rock geology was encountered, in which the highest salt content reached 80%. During the construction, it was discovered that the tunnel invert and filling concrete cracked and bulged, the cast-in-place lining concrete had longitudinal and circumferential cracks, and the low side wall had shear failure. Due to the high salt content and complex composition of the salt rock strata of the Friendship Tunnel, which is extremely corrosive to metal materials, the tunnel construction disturbed the equilibrium state of groundwater, which led to the dissolution, transfer, and recrystallization of salt rock, thereby changing the tunnel confining pressure state and causing structural damage. It is necessary to set up a waterproof layer under the tunnel bottom invert.

[0003] Unlike conventional tunnels, the salt rock section requires an additional waterproof layer at the bottom of the tunnel, which is equivalent to constructing two layers of inverts, and increases the curvature and depth. Conventional equipment and processes cannot meet the requirements. Summary of the invention

[0004] The purpose of the present invention includes providing a supporting tooling system for the construction of multi-layer inverted arches in salt rock tunnel strata, which can use a fully enclosed formwork for casting, ensure the shape and size of the casting structure and the construction quality, especially the casting of the waterproof structure, and meet the process and traffic organization requirements through a self-propelled long trestle.

[0005] Another object of the present invention is to provide a method for constructing a multi-layer inverted arch in a salt rock tunnel stratum to ensure the shape, size and construction quality of the cast structure.

[0006] The embodiments of the present invention are implemented by the following technical solutions:

[0007] A tooling system for the construction of multi-layer inverted arches in salt rock tunnel strata comprises a fully enclosed formwork and a self-propelled long trestle. The fully enclosed formwork is provided with a head plate and an intermediate long formwork distributed along the axial direction of the tunnel. The intermediate long formwork is separated from the wall surface of the tunnel working area by a preset distance. The fully enclosed formwork and the wall surface of the tunnel working area enclose a concrete filling area. The self-propelled long trestle is used to assist the movement of the intermediate long formwork.

[0008] Preferably, the middle long formwork is provided with an anti-floating member, one end of the anti-floating member is fixedly connected to the middle long formwork, and the other end is fixed to the primary support of the tunnel.

[0009] Preferably, the anti-floating component comprises an anti-floating jack, one end of which is fixedly connected to one side of the middle long template, and the other end of which is fixedly connected to the primary support of the tunnel.

[0010] Preferably, the anti-floating members are arranged in pairs, and are respectively arranged outside the axial sides of the middle long template.

[0011] Preferably, the middle long template is equipped with a template jack, one end of the template jack is fixedly connected to the middle long template, and the other end is fixed to the self-propelled long trestle;

[0012] The self-propelled long trestle is equipped with an end beam cross brace jack, one end of which is fixed to the self-propelled long trestle, and the other end is fixed to the wall of the tunnel working area.

[0013] Preferably, the middle long template is provided with a plurality of through feeding windows along the distribution plane, each feeding window is equipped with a channel connected to the main hopper on the top of the trolley, and the feeding windows are used for feeding concrete into the mold window by window.

[0014] Preferably, the invention is applied to a salt rock tunnel, wherein the invert structure area of ​​the salt rock tunnel includes a grouting tunnel bottom, a water-proof layer and an invert secondary lining;

[0015] The wall surface of the tunnel operation area includes the upper surface of the grouting tunnel bottom. The middle long formwork is separated from the upper surface of the grouting tunnel bottom by a preset distance. The fully enclosed formwork and the upper surface of the grouting tunnel bottom enclose a concrete filling area.

[0016] Preferably, the self-propelled long trestle includes a front approach bridge, a main bridge, a rear approach bridge and a traveling mechanism, one end of the front approach bridge is connected to the front end of the main bridge, one end of the rear approach bridge is connected to the rear end of the main bridge, and the traveling mechanism is used for moving the main bridge.

[0017] A method for constructing a multi-layer inverted arch in a salt rock tunnel stratum includes the above-mentioned supporting tooling system for constructing a multi-layer inverted arch in a salt rock tunnel stratum, including:

[0018] Step 1, move the trolley to lift the middle long template to the working area;

[0019] Step 2: Install the end beam cross brace jack, template jack and anti-floating jack, and fix the middle long template;

[0020] Step 3, install the headboard, pour concrete and vibrate;

[0021] Step 4: Cure the concrete in the formwork. After the curing period is reached, lift the fully enclosed formwork and demold for curing.

[0022] The technical solution of the embodiment of the present invention has at least the following advantages and beneficial effects:

[0023] 1. Use fully enclosed formwork to ensure the shape, size and construction quality of the casting structure, especially the waterproof layer, which is conducive to achieving the preset waterproof effect;

[0024] 2. Meet the requirements of process and traffic organization, which is beneficial to on-site operation and operation time. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 A first structural schematic diagram of a tooling system for construction of multi-layer inverts in salt rock tunnel strata is provided for an embodiment of the present invention;

[0027] Figure 2 A second structural schematic diagram of a tooling system for construction of multi-layer inverts in salt rock tunnel strata is provided for an embodiment of the present invention;

[0028] Figure 3 A schematic diagram of the structure of the cooperation between the middle long template and the head plate is provided for an embodiment of the present invention;

[0029] Figure 4 The present invention provides a structural schematic diagram of a self-propelled long trestle.

[0030] Icons: 100-fully enclosed formwork, 110-head plate, 120-middle long formwork, 121-anti-floating parts, 121a-primary support of the tunnel, 122-feeding window, 130-wall of the tunnel working area, 131-area to be filled with concrete, 200-self-propelled long trestle, 210-end beam cross brace jack, 220-front approach bridge, 230-main bridge, 240-rear approach bridge, 250-traveling mechanism, 310-mobile trolley, 320-side formwork cylinder, 330-demolding cylinder, 340-lateral adjustment mechanism, 350-vertical adjustment mechanism. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0032] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0034] In the description of the present invention, it should be noted that if the terms "center", "up", "down", "vertical", "horizontal", "inside", "outside" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the invention is usually placed when used. It is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0035] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] Please refer to Figures 1 to 4 , Figures 1 to 4 Provided is a tooling system for the construction of multi-layer inverts in salt rock tunnel strata. Figure 1 This is a radial cross-sectional view of the tunnel invert construction. Figure 2 Axial perspective view of the tunnel invert construction. Figure 3 Compared to Figure 2 Install the head plate 110, Figure 4 It is the general structure of the self-propelled long trestle 200.

[0037] The inventors found that during the construction of railway tunnels, salt rock geological layers were encountered. Since salt rock dissolves in water, it is extremely corrosive to metal materials. Tunnel construction disturbs the equilibrium state of groundwater, which leads to the dissolution, transfer, and recrystallization of salt rock, thereby changing the tunnel confining pressure state and causing structural damage. The inverted arch structure currently used in conventional tunnels, with its single inverted arch layer, cannot play the role of blocking moisture. In a salt rock environment, the salt rock geology will corrode the concrete of the inverted arch layer, causing structural damage, affecting the safety of the tunnel and the railway, and posing a major hidden danger.

[0038] Therefore, it is necessary to set up a waterproof layer in the invert structure of the tunnel. The setting of the waterproof layer must be studied. After the shape and structure of the waterproof layer are determined, the construction of the waterproof layer is carried out. The waterproof layer with a certain structure and shape must be obtained to complete the established good waterproofing function.

[0039] However, in conventional tunnels, after the invert is excavated, the end and side wall formworks are directly closed, and the shape and structure of the concrete cannot be controlled when filling the concrete, which has an adverse effect on the purpose of obtaining a specific waterproof layer.

[0040] The inventor has found through research that it is currently impossible to control the shape and structure of the waterproof layer after construction, mainly the upper surface of the waterproof layer concrete. In addition, tunnel excavation in the salt rock geological layer has poor geology, poor strength and rigidity. Because it involves multiple layers of "inverted arches" such as inverted arches and waterproof layers, the depth of the inverted arch structure is large. The installation of ordinary trestle templates requires on-site splicing, which cannot be moved manually and must be transported by equipment. The same is true for disassembly. There are many auxiliary tooling and operations, which puts great pressure on the construction period and on-site operations.

[0041] Based on this, the inventor invented a tooling system for the construction of multi-layer inverted arches in salt rock tunnel strata, which adopts a fully enclosed template 100 and a self-propelled long trestle 200 to ensure the shape, size and construction quality of the waterproof layer. Based on the construction of the inverted arch in the tunnel with a waterproof layer, the fully enclosed template 100 is adopted, and the long trestle is used in the construction, and the template in the long trestle has anti-floating measures.

[0042] For details, please refer to Figure 2 and Figure 3 The fully enclosed template 100 and the self-propelled long trestle 200 cooperate with each other. The fully enclosed template 100 includes a head plate 110 and an intermediate long template 120. The intermediate long template 120 is distributed along the axial direction of the tunnel. The intermediate long template 120 is separated from the wall surface 130 of the tunnel working area by a preset distance, and the preset distance is set by the predetermined waterproof layer size studied in advance.

[0043] The fully enclosed formwork 100 and the tunnel operation area wall 130 enclose a concrete-to-be-filled area 131 , and concrete is filled in the concrete-to-be-filled area 131 to construct a waterproof layer.

[0044] The self-propelled long trestle 200 only needs to be assembled once and moved forward and backward by a trolley. Compared with the short trestle, it has the beneficial effects of simple operation and reasonable use of space.

[0045] It should be noted that the above-mentioned waterproof layer actually refers to the case where the tunnel operation area wall surface 130 is selected as the upper surface of the grouting tunnel bottom. The salt rock tunnel stratum multi-layer invert construction supporting tooling system of this embodiment can be used for the construction of waterproof layers and other invert layers.

[0046] It should be noted that the area to be filled with concrete 131 can be used to pour concrete for the lining at the invert.

[0047] In the case of a waterproof layer, the system is used in salt rock tunnels or other tunnels that require waterproofing. In the salt rock tunnel, the inverted arch structure area includes the grouting tunnel bottom, the waterproof layer, the inverted arch secondary lining and the inverted arch filling. The middle long template 120 is separated from the upper surface of the grouting tunnel bottom by a preset distance, and the fully enclosed template 100 and the upper surface of the grouting tunnel bottom enclose a concrete to-be-filled area 131. Furthermore, further waterproofing treatment similar to a waterproof cloth can be performed between the grouting tunnel bottom and the waterproof layer, and between the waterproof layer and the inverted arch secondary lining, respectively, to improve the waterproofing effect.

[0048] Please refer to Figure 4 The self-propelled long trestle 200 includes a front approach bridge 220, a main bridge 230, a rear approach bridge 240 and a traveling mechanism 250. One end of the front approach bridge 220 is connected to the front end of the main bridge 230, and one end of the rear approach bridge 240 is connected to the rear end of the main bridge 230. The traveling mechanism 250 is used for moving the main bridge 230. For example, patent number CN109139039A discloses a structure of a self-propelled long trestle 200.

[0049] The supporting tooling system for the construction of multi-layer inverts in salt rock tunnel strata is used to ensure the shape, size and construction quality of the casting structure, especially the waterproof layer, which is conducive to achieving the preset waterproof effect and stabilizing the tunnel structure in the later stage; meeting the requirements of the process and traffic organization, facilitating on-site operations and operating time.

[0050] Preferably, anti-floating measures are taken for the middle long formwork 120. Because the formwork is ensured not to shake when pouring concrete (a car passes by the trestle), the trolley will be disconnected from the connected formwork when pouring concrete, and the formwork support is mainly positioned by the vertical adjustment mechanism and the horizontal adjustment mechanism. When the concrete is filled into the concrete to be filled area 131 until it is almost full, the concrete will cause an upward buoyancy to the middle long formwork 120, affecting the spatial position of the middle long formwork 120. Please refer to Figure 1 The middle long formwork 120 is provided with an anti-floating member 121, one end of which is fixedly connected to the middle long formwork 120, and the other end is fixed to the tunnel primary support 121a (i.e., initial support). The anti-floating member 121 is used to resist the upward trend of the position of the middle long formwork 120, which is further beneficial to the shape, size and construction quality of the cast structure.

[0051] The anti-floating member 121 is used to provide a layer of anti-floating for the middle long template 120 , and the deadweight of the pier and the template can also be used to resist the floating tendency of the middle long template 120 , thus achieving double anti-floating interaction.

[0052] Preferably, please refer to Figure 3 The anti-floating members 121 are arranged in pairs, each anti-floating member 121 is arranged outside the axial sides of the middle long template 120, and the plurality of anti-floating members 121 are arranged in sequence at the axial side ends of the middle long template 120.

[0053] Preferably, the anti-floating member 121 can be in the form of an anti-floating jack, which has the advantages of adjustable longitudinal length and strong stability.

[0054] Preferably, please refer to Figure 2 and Figure 3 The middle long formwork 120 is equipped with a formwork jack, one end of which is fixedly connected to the middle long formwork 120, and the other end is fixed to the self-propelled long trestle 200. The self-propelled long trestle 200 is equipped with an end beam cross brace jack 210, one end of which is fixed to the self-propelled long trestle 200, and the other end is fixed to the wall surface 130 of the tunnel operation area. Both are used to stabilize the position of the fully enclosed formwork 100.

[0055] Preferably, the concrete to be filled area 131 is filled with concrete in a window-by-window manner. The middle long formwork 120 is provided with a plurality of through-feeding windows 122 along the distribution plane, each of which is equipped with a channel connected to the main hopper on the top of the trolley, and the feed windows 122 are used to feed concrete into the mold window by window. Each window is fed with material at the same time, and the feeding speed and quantity are basically consistent and uniform, which is convenient for controlling the thickness layering of concrete during the construction process.

[0056] Regarding the window-by-window mold placement, all the material entry windows are placed along the central axis of the tunnel to both sides, and the principle of "layered pouring and symmetrical pouring" is adopted. For example, along the horizontal radial direction, it is divided into 3 areas, 2 areas, 1 area, 2 areas, and 3 areas. The pouring construction sequence is 1-2-3, symmetrical up and down, left and right. Each area is divided into three windows on the left, middle and right, and poured at the same time. When pouring the water-proof structure, when pouring 0.5m in a single area, three windows are changed for pouring (each area has two rows of 6 windows in total, and two windows are poured 0.5m each to obtain a water-proof structure with a total thickness of 1m)

[0057] This embodiment also provides a method for constructing a multi-layer inverted arch in a salt rock tunnel stratum, including the above-mentioned supporting tooling system for constructing a multi-layer inverted arch in a salt rock tunnel stratum, and comprising the following four steps:

[0058] Step 1, the mobile trolley 310 lifts the middle long template 120 to the working area;

[0059] Step 2, install the end beam cross brace jack 210, the template jack and the anti-floating jack, and fix the middle long template 120;

[0060] Step 3, installing the head plate 110, pouring concrete and vibrating;

[0061] Step 4: concrete is cured in the formwork. After the curing period is reached, the fully enclosed formwork is lifted 100 and demolded for curing.

[0062] Please refer to Figure 1 and Figure 4A movable trolley 310 is provided on the main bridge 230 of the self-propelled long trestle 200, and the movable trolley 310 lifts the middle long template 120 to the working area. The self-propelled long trestle 200 is provided with a lateral adjustment mechanism 340 and a vertical adjustment mechanism 350, so as to move the middle long template 120 to the best position.

[0063] Next, install the end beam cross brace jack 210, formwork jack and anti-floating jack. The two ends of the end beam cross brace jack 210 are respectively connected to the self-propelled long trestle 200 and the tunnel working area wall 130. The two ends of the formwork jack are respectively connected to the middle long formwork 120 and the self-propelled long trestle 200. Combined with the operation of the anti-floating jack, a good position fixing effect of the middle long formwork 120 is achieved.

[0064] Please refer to Figure 2 and Figure 3 Then, the head plate 110 is installed to form a concrete filling area 131, and concrete is poured and vibrated to ensure the quality of the concrete component. The concrete is poured and vibrated at the same time, and the vibration is carried out by an attached vibrator and an inserted vibrator. The waterproof layer must not be touched during the vibration.

[0065] Concrete is cured with formwork. After the curing period is reached, the fully enclosed formwork is lifted 100 and demolded for curing. Figure 1 The side mold cylinder 320 and the demoulding cylinder 330 are shown in the figure, which are used for the demoulding operation of the fully enclosed template 100.

[0066] The multi-layer invert construction method in salt rock tunnel strata can not only be used for the precise pouring of waterproof layers, but can also be used in other situations where there are specific requirements for structural dimensions. It is not limited to waterproof layers, but other forms of invert layers can also be used.

[0067] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A tooling system for the construction of multi-layer inverts in salt rock tunnel strata, characterized in that: include: A fully enclosed formwork, wherein the fully enclosed formwork is provided with a head plate and an intermediate long formwork distributed along the axial direction of the tunnel, the intermediate long formwork is separated from the wall surface of the tunnel working area by a preset distance, and the fully enclosed formwork and the wall surface of the tunnel working area enclose a concrete filling area; A self-propelled long trestle bridge, used to assist the movement of the intermediate long template; The template is connected with a horizontal adjustment mechanism and a vertical adjustment mechanism; The middle long template is equipped with an anti-floating member, one end of the anti-floating member is fixedly connected to the middle long template, and the other end is fixed to the primary support of the tunnel; The anti-floating part includes an anti-floating jack, one end of which is fixedly connected to one side of the middle long template, and the other end is fixedly connected to the tunnel primary support; The anti-floating parts are arranged in pairs, and are respectively arranged outside the axial sides of the middle long template; Applied to salt rock tunnels, the invert structure area of ​​salt rock tunnels includes grouting tunnel bottom, waterproof layer, and invert secondary lining; The wall surface of the tunnel operation area includes the upper surface of the grouting tunnel bottom, the middle long template is separated from the upper surface of the grouting tunnel bottom by a preset distance, and the fully enclosed template and the upper surface of the grouting tunnel bottom enclose a concrete filling area.

2. The tooling system for construction of multi-layer inverts in salt rock tunnel strata according to claim 1 is characterized by: The middle long template is equipped with a template jack, one end of which is fixedly connected to the middle long template, and the other end is fixed to the self-propelled long trestle; The self-propelled long trestle is equipped with an end beam cross-bracing jack, one end of the end beam cross-bracing jack is fixed to the self-propelled long trestle, and the other end is fixed to the wall surface of the tunnel operation area.

3. The tooling system for construction of multi-layer inverts in salt rock tunnel strata according to claim 1 is characterized by: The middle long template is provided with a plurality of through feeding windows along the distribution plane, each of the feeding windows is equipped with a channel connected to the main hopper on the top of the trolley, and the feeding windows are used for feeding concrete into the mold window by window.

4. The tooling system for construction of multi-layer inverted arches in salt rock tunnel strata according to claim 1 is characterized by: The self-propelled long trestle comprises a front approach bridge, a main bridge, a rear approach bridge and a walking mechanism, one end of the front approach bridge is connected to the front end of the main bridge, one end of the rear approach bridge is connected to the rear end of the main bridge, and the walking mechanism is used for moving the main bridge.

5. A method for constructing a multi-layer inverted arch in a salt rock tunnel stratum, comprising the supporting tooling system for constructing a multi-layer inverted arch in a salt rock tunnel stratum according to any one of claims 1 to 4, characterized in that: include: Step 1, moving the trolley to lift the middle long template to the working area; Step 2, installing the end beam cross brace jack, template jack and anti-floating jack, and fixing the middle long template; Step 3, installing the headboard, pouring concrete and vibrating; Step 4, concrete is cured in the formwork. After the curing period is reached, the fully enclosed formwork is lifted and demolded for curing.

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