Inner and outer double-layer bidirectional anti-seepage high-pressure pipeline lining structure and construction method thereof

Abstract

The invention provides an inner and outer double-layer two-way anti-seepage high-pressure pipeline lining structure and a construction method thereof, and belongs to the technical field of pipeline construction. The inner and outer double-layer two-way anti-seepage high-pressure pipeline lining structure comprises a concrete layer and a rock surrounding layer; the second impermeable layer is clamped between the concrete layer and the surrounding rock layer; a fixing structure is arranged between the first impermeable layer and the inner wall of the concrete layer; high-pressure water is prevented from directly acting on the reinforced concrete lining structure and a thin film layer between the reinforced concrete lining and the surrounding rock, so that the reinforced concrete lining structure falls off after being cracked and is scoured by water flow, and a thin film impermeable layer between the reinforced concrete lining and the surrounding rock is prevented from being broken down due to the uneven surrounding rock surface; the situation that underground water directly acts on the impermeable layer of the inner layer through cracks of the reinforced concrete lining, and consequently the impermeable layer is punctured, torn or deformed or unstable is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of pipeline construction, and in particular to an inner and outer double-layer bidirectional anti-seepage high-pressure pipeline lining structure and a construction method thereof. Background Art

[0002] For high-head power stations, especially pumped-storage power stations, the maximum internal water pressure head of the water transmission system often reaches hundreds of meters, or even thousands of meters. Conventional reinforced concrete lining structures and design methods based on crack containment are no longer suitable. Currently, high-pressure pipelines are commonly lined with steel plates, prestressed reinforced concrete linings, and anti-seepage membrane composite concrete linings.

[0003] Steel plate lining is the most commonly used lining structure for high-pressure pipelines. For this type of lining structure, the steel plate, as the main load-bearing structure of the pipeline, not only bears high internal water pressure, but also has to bear large external water pressure. Circumferential stiffening rings with large thickness and small distribution spacing are required to improve its ability to resist external pressure. It is usually characterized by large steel plate thickness, high construction difficulty and high project investment.

[0004] Prestressed concrete lining is achieved by applying prestress in the pipe concrete lining structure to improve the bearing capacity. According to the form of prestressing in the lining, it can be divided into grouting prestressing and mechanical ring anchor prestressing structure. However, due to the complexity of prestressed concrete lining construction and the difficulty in controlling the effect, it is currently rarely used in engineering practice.

[0005] Impermeable membrane composite concrete lining. This type of lining incorporates an impermeable membrane, such as a thin steel lining or polyvinyl chloride (PVC) water-stopping material, between two layers of concrete or between concrete and surrounding rock. The inner layer of concrete on the water-facing side protects the membrane from damage while also absorbing external water pressure, preventing the membrane from being damaged. Its design principle is to transfer all or most of the internal water pressure to the surrounding rock. Therefore, the tunnel surrounding rock must still meet the "minimum cover thickness criterion" and "minimum in-situ stress criterion." This limits its scope of application and poses the risk of cracking and shedding of the inner concrete layer under high internal water pressure and water erosion, compromising the safe operation of flow-passing components. Summary of the Invention

[0006] In order to overcome the deficiencies of the prior art, the technical problem to be solved by the present invention is: how to prevent the reinforced concrete lining structure of the high-pressure pipeline from cracking and falling off under the action of high internal water pressure and water flow scouring, and how to prevent high-pressure water from seeping through the cracks in the lining structure.

[0007] The technical solution adopted by the present invention to solve its technical problem is: A high-pressure pipeline lining structure with double inner and outer layers and bidirectional anti-seepage, comprising a concrete layer and a surrounding rock layer, wherein a first anti-seepage layer and a second anti-seepage layer are respectively provided on the inner and outer sides of the concrete layer, and the second anti-seepage layer is sandwiched between the concrete layer and the surrounding rock layer; a fixed structure is provided between the first anti-seepage layer and the inner wall of the concrete layer.

[0008] Furthermore, the first anti-seepage layer and the second anti-seepage layer are both elastic layers.

[0009] Furthermore, the fixing structure includes an adhesive layer.

[0010] Furthermore, the above-mentioned fixing structure includes a fastening bolt structure.

[0011] Furthermore, the second anti-seepage layer includes a flexible anti-seepage coating, a thin steel plate with a corrugated expansion device, a polyvinyl chloride waterproof sheet or a geomembrane.

[0012] Furthermore, the second anti-seepage layer comprises a thin steel plate, a copper sheet or a flexible anti-seepage coating with a corrugated expansion device.

[0013] A construction method for a high-pressure pipeline lining structure with an inner and outer double-layer bidirectional anti-seepage function comprises the following steps: S1: Clean the inner surface of the tunnel after excavation and support; S2: Setting a second anti-seepage layer on the inner surface of the tunnel; S3: pouring a concrete layer on the outer wall of the first anti-seepage layer; S4: Setting a first anti-seepage layer on the inner wall of the concrete layer.

[0014] Furthermore, in step S4, a first anti-seepage layer is disposed on the inner wall of the concrete layer, and the first anti-seepage layer is fixed to the concrete layer by a connecting member.

[0015] The beneficial effects of the present invention are: By setting a first anti-seepage layer and a second anti-seepage layer, that is, setting a thin film layer that can adapt to deformation and has an anti-seepage function on the inner water-facing surface of the reinforced concrete lining structure of the high-pressure pipeline and between the reinforced concrete lining and the surrounding rock, an anti-seepage layer is set on the water-facing surface of the inner layer of the reinforced concrete lining to prevent high-pressure water from directly acting on the reinforced concrete lining structure and the thin film layer between the reinforced concrete lining and the surrounding rock, which may cause the reinforced concrete lining structure to crack and then be washed away by water flow and fall off, and the thin film anti-seepage layer between the reinforced concrete lining and the surrounding rock to be penetrated due to the unevenness of the surrounding rock surface. An anti-seepage layer is set on the outer layer of the lining structure, that is, between the reinforced concrete lining and the surrounding rock, to prevent groundwater from directly acting on the inner anti-seepage layer through the cracks in the reinforced concrete lining to cause it to be penetrated, torn or deformed, and unstable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic structural diagram of the present invention; Marked in the figure are: 1-surrounding rock layer, 2-concrete layer, 3-first anti-seepage layer, 4-second anti-seepage layer. DETAILED DESCRIPTION

[0017] The present invention will be further described below with reference to the accompanying drawings.

[0018] like Figure 1 As shown, an embodiment of the present application proposes an inner and outer double-layer bidirectional anti-seepage high-pressure pipeline lining structure, comprising a concrete layer 2 and a surrounding rock layer 1, wherein a first anti-seepage layer 3 and a second anti-seepage layer 4 are respectively provided on the inner and outer sides of the above-mentioned concrete layer 2, and the above-mentioned second anti-seepage layer 4 is sandwiched between the above-mentioned concrete layer 2 and the above-mentioned surrounding rock layer 1; a fixed structure is provided between the above-mentioned first anti-seepage layer 3 and the inner wall of the above-mentioned concrete layer 2.

[0019] That is, an anti-seepage layer, namely a first anti-seepage layer 3 and a second anti-seepage layer 4, is provided on the inner water-facing surface of the reinforced concrete lining structure of the high-pressure pipeline and between the reinforced concrete lining and the surrounding rock. The reinforced concrete lining structure serves as the carrier of the inner and outer bidirectional anti-seepage layers and is also a load-bearing and force-transmitting structure. On the one hand, the concrete itself and the steel bars arranged therein can bear part of the internal water pressure, and on the other hand, it can transmit the internal water pressure to the surrounding rock. The first anti-seepage layer 3 is provided on the inner water-facing surface of the reinforced concrete lining to prevent high-pressure water from directly acting on the reinforced concrete lining structure and the thin film layer between the reinforced concrete lining and the surrounding rock, which could cause the reinforced concrete lining structure to crack and fall off due to water erosion, and the thin film anti-seepage layer between the reinforced concrete lining and the surrounding rock to be penetrated due to the uneven surrounding rock surface. The anti-seepage layer is provided on the outer layer of the concrete layer 2, that is, between the concrete layer 2 and the surrounding rock layer 1, to prevent groundwater from directly acting on the inner anti-seepage layer through cracks in the reinforced concrete lining, causing it to be penetrated, torn, deformed, or unstable.

[0020] Furthermore, the first anti-seepage layer 3 and the second anti-seepage layer 4 need to have greater elasticity and good anti-seepage performance. At the same time, the inner anti-seepage film layer has good bonding performance with the reinforced concrete lining or can be firmly connected to the reinforced concrete through connecting components to adapt to the local large deformation caused by cracking of the reinforced concrete lining and avoid the anti-seepage film layer from falling off due to shear deformation along the contact surface.

[0021] The aforementioned concrete layer 2, by arranging steel bars within the lining concrete, prevents the concrete lining structure from cracking and losing its integrity under high internal water pressure, while also preventing the thin layer structure on the water-facing surface from bearing excessive internal water pressure and the weight of the cracked concrete itself. The first impermeable layer 3 is a deformable, impermeable membrane layer provided on the inner, water-facing surface of the concrete layer 2. This prevents high-pressure water from directly acting on the reinforced concrete lining structure and the membrane layer between the reinforced concrete lining and the surrounding rock, which could cause the reinforced concrete lining structure to fall off after being eroded by water flow, and the membrane layer between the reinforced concrete lining and the surrounding rock to be penetrated due to the unevenness of the surrounding rock surface. The second impermeable layer 4, the membrane layer between the reinforced concrete lining and the surrounding rock, is supported by the reinforced concrete lining and is not in a tensile state, allowing it to withstand significant external water pressure. This protects the membrane layer on the water-facing surface from excessive splitting forces or penetration between the membrane layer and the reinforced concrete, or from instability due to excessive external water pressure.

[0022] A construction method for a high-pressure pipeline lining structure with an inner and outer double-layer bidirectional anti-seepage function comprises the following steps: S1: Clean the inner surface of the tunnel after excavation and support; S2: Setting a second anti-seepage layer 4 on the inner surface of the tunnel; S3: pouring concrete layer 2 on the outer wall of the first anti-seepage layer 3; S4: A first anti-seepage layer 3 is set on the inner wall of the concrete layer 2.

[0023] Furthermore, in step S4, a first anti-seepage layer 3 is disposed on the inner wall of the concrete layer 2, and the first anti-seepage layer 3 is fixed to the concrete layer 2 by a connecting member.

[0024] Specifically, after the excavation, support and consolidation grouting of the tunnel are all completed, an anti-seepage layer, i.e., the second anti-seepage layer 4, is first applied to the cleaned inner surface of the tunnel. The anti-seepage layer can use flexible anti-seepage coating, thin steel plates with corrugated expansion devices, copper sheets, or polyvinyl chloride (PVC) waterproof sheets or geomembranes, and other materials with good anti-seepage performance and strong adaptability to deformation; secondly, reinforced concrete lining is applied, that is, a concrete layer 2 is poured on the inner wall of the first anti-seepage layer 3; finally, an inner water-facing anti-seepage layer is applied, which can be made of thin steel plates with corrugated expansion devices, copper sheets, or flexible anti-seepage coatings, and other materials with good anti-seepage performance and strong adaptability to deformation, that is, a first anti-seepage layer 3 is set on the inner wall of the concrete layer 2.

[0025] The inner and outer anti-seepage film layers of the lining need to have great elasticity and good anti-seepage performance. At the same time, the inner anti-seepage film layer must have good bonding properties with the reinforced concrete lining or can be firmly connected to the reinforced concrete through connecting components to adapt to local large deformation caused by cracking of the reinforced concrete lining and avoid the anti-seepage film layer from falling off due to shear deformation along the contact surface.

[0026] In summary, the present invention proposes an inner and outer double-layer bidirectional anti-seepage high-pressure pipeline lining structure and a construction method. By arranging a first anti-seepage layer 3 and a second anti-seepage layer 4, high-pressure water is prevented from directly acting on the reinforced concrete lining structure and the thin film layer between the reinforced concrete lining and the surrounding rock, which may cause the reinforced concrete lining structure to crack and fall off due to water erosion, and the thin film layer between the reinforced concrete lining and the surrounding rock to be penetrated due to the uneven surrounding rock surface; at the same time, it can withstand a large external water pressure, thereby protecting the water-facing surface thin film layer to avoid excessive splitting force or penetration between the thin film layer and the reinforced concrete due to excessive external water pressure, or the thin film layer itself becoming unstable; and the cost of the entire structure is relatively low and the construction difficulty is relatively small.

Claims

1. A high-pressure pipeline lining structure with double inner and outer layers and bidirectional anti-seepage, characterized by: The invention comprises a concrete layer (2) and a surrounding rock layer (1); a first anti-seepage layer (3) and a second anti-seepage layer (4) are respectively provided on the inner and outer sides of the concrete layer (2); the second anti-seepage layer (4) is sandwiched between the concrete layer (2) and the surrounding rock layer (1); and a fixed structure is provided between the first anti-seepage layer (3) and the inner wall of the concrete layer (2).

2. The high-pressure pipeline lining structure with double inner and outer layers and bidirectional anti-seepage according to claim 1 is characterized by: The first anti-seepage layer (3) and the second anti-seepage layer (4) are both elastic layers.

3. The high-pressure pipeline lining structure with double inner and outer layers and bidirectional anti-seepage according to claim 1 is characterized by: The fixing structure includes an adhesive layer.

4. The high-pressure pipeline lining structure with double inner and outer layers and bidirectional anti-seepage according to claim 1 is characterized by: The fixing structure includes a fastening bolt structure.

5. The high-pressure pipeline lining structure with double inner and outer layers and bidirectional anti-seepage according to claim 1 is characterized by: The second anti-seepage layer (4) comprises a flexible anti-seepage coating, a thin steel plate with a corrugated expansion device, a polyvinyl chloride waterproof sheet or a geomembrane.

6. The high-pressure pipeline lining structure with double inner and outer layers and bidirectional anti-seepage according to claim 1 is characterized by: The first anti-seepage layer (3) comprises a corrugated telescopic steel plate, a copper sheet or a flexible anti-seepage coating connected to the inner wall of the concrete layer (2).

7. A construction method for a high-pressure pipeline lining structure with double inner and outer layers and bidirectional anti-seepage, characterized by: The following steps are involved: S1: Clean the inner surface of the tunnel after excavation and support; S2: providing a second anti-seepage layer (4) on the inner surface of the tunnel; S3: pouring a concrete layer (2) on the inner wall of the first anti-seepage layer (3); S4: Arranging a first anti-seepage layer (3) on the inner wall of the concrete layer (2).

8. The construction method of a double-layer bidirectional anti-seepage high-pressure pipeline lining structure according to claim 7, characterized in that: In step S4, a first anti-seepage layer (3) is arranged on the inner wall of the concrete layer (2), and the first anti-seepage layer (3) and the concrete layer (2) are fixed by a connecting member.

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