Large-diameter double-steel-plate concrete composite pipe based on load balance method

Abstract

The application discloses a large-diameter double-steel-plate concrete combined pipeline based on a load balancing method, which is assembled by a plurality of double-steel-plate concrete pipe segments along an axial direction, characterized in that an external pressure applying structure is arranged on the outside of part or all of the double-steel-plate concrete pipe segments, the external pressure applying structure applies external pressure to the double-steel-plate concrete pipe segments in the direction opposite to the direction of water pressure in the pipe, so as to offset part of the water pressure in the pipe. The application adopts a double-steel-plate concrete combined structure, has the advantages of high bearing capacity, large rigidity, good stability and the like, fills the concrete between the combined pipeline and the rock mass, realizes the common stress of the combined pipeline and the rock mass, applies the external pressure to the pipeline in advance by using prestressed support rods, so as to offset part of the water pressure in the pipeline, reduce the use load effect of the pipeline, effectively reduce the thickness of the steel plate and the strength of the steel, save the material consumption, reduce the engineering cost and have good economic benefits.

Description

Technical Field

[0001] This invention belongs to the field of pressure pipeline technology for pumped storage power stations, and specifically relates to a large-diameter double steel plate concrete composite pipeline based on the load balance method. Background Technology

[0002] As an important component of pumped storage power stations and a core channel for energy conversion, the stability of their safe operation is of paramount importance.

[0003] Currently, steel plate lining is the primary type of lining for pressure pipelines. Steel plates offer high strength and good impermeability. However, with the application of large-megawatt pumped storage power stations, the steel lining is subjected to greater internal water pressure during operation, significantly increasing the thickness and strength of the steel plates, thus raising construction and maintenance costs. Furthermore, when the pipeline is vented, the steel lining may become unstable under external pressure, severely hindering the widespread adoption and application of steel-lined pipelines. Summary of the Invention

[0004] In order to overcome the shortcomings of the prior art, the present invention aims to provide a large-diameter double steel plate concrete composite pipe based on the load balance method, so as to reduce the load effect of the pipe, reduce the thickness of the steel plate and the strength of the steel, save material usage and reduce project cost.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A large-diameter double-steel-plate concrete composite pipeline based on the load balance method is assembled from several double-steel-plate concrete pipe sections along the axial direction. An external pressure application structure is provided on the outside of some or all of the double-steel-plate concrete pipe sections. The external pressure application structure applies an external pressure to the double-steel-plate concrete pipe sections in the opposite direction to the water pressure inside the pipe, so as to offset part of the water pressure inside the pipe.

[0007] In one embodiment, the external pressure applying structure includes a concrete lining and a plurality of prestressed struts; the concrete lining fills the space between the double-plate concrete pipe segment and the rock mass; one end of each prestressed strut is connected to the outer wall of the double-plate concrete pipe segment, and the other end is anchored inside the concrete lining.

[0008] In one embodiment, the length direction of the prestressed strut is consistent with the radial direction of the combined pipe, and the prestressed struts are arranged at equal intervals along the circumferential and axial directions of the combined pipe.

[0009] In one embodiment, the length of the double-plate concrete pipe is 2-4m, the inner diameter is not less than 8m, and the outer diameter is not less than 10m. The thickness of the concrete lining is not less than 100mm. The length of the prestressed strut is not greater than half the thickness of the concrete lining.

[0010] In one embodiment, the double-plate concrete pipe segment includes:

[0011] Outer steel pipe or curved outer steel plate;

[0012] Inner steel pipe or curved inner steel plate;

[0013] The concrete sandwiched between the outer steel pipe or the arc-shaped outer steel plate and the inner steel pipe or the arc-shaped inner steel plate, when using the arc-shaped outer steel plate and the arc-shaped inner steel plate, is spliced ​​into pipe sections along the circumferential direction.

[0014] In one embodiment, the interlayer concrete is poured in a precast or cast-in-place manner, and the interlayer concrete is high-strength concrete, recycled concrete, self-compacting concrete, fiber-reinforced concrete (FRC), reactive powder concrete (RPC), or ultra-high performance concrete (UHPC). The inner wall of the outer steel pipe or arc-shaped outer steel plate and / or the outer wall of the inner steel pipe or arc-shaped inner steel plate are provided with studs, which are arranged in a square or quincunx pattern.

[0015] In one embodiment, the concrete lining is cast-in-place, and the concrete lining is ordinary concrete, high-strength concrete, recycled concrete, or self-compacting concrete.

[0016] In one embodiment, the external pressure applying structure is a concrete lining, which is expansive concrete, filling the space between the double-plate concrete pipe section and the rock mass.

[0017] In one embodiment, the inner diameter of the combined pipeline is not less than 8m and the outer diameter is not less than 10m. The self-stress of the expansive concrete is not less than 0.2MPa and not less than the design critical external pressure of the double-steel-plate concrete pipe section.

[0018] In one embodiment, the double-plate concrete pipe section can be replaced with a pure steel pipe section or a hollow steel pipe concrete pipe section.

[0019] Compared with the prior art, the beneficial effects of the present invention are:

[0020] 1) Convenient construction

[0021] Large-diameter double-steel-plate concrete composite pipes based on the load balance method have a simple structure and are easy to construct. The composite pipe is assembled in sections along the axial direction, and adjacent sections are welded together to form the pipe. The inner and outer steel plates replace the reinforcing bars of the reinforced concrete and act as the formwork for pouring concrete, eliminating the need for formwork erection and dismantling, thus facilitating construction, shortening the construction cycle, and improving construction efficiency.

[0022] 2) Performance improvement

[0023] Large-diameter double-steel-plate concrete composite pipelines based on the load balance method adopt a double-steel-plate concrete composite structure, which has advantages such as high load-bearing capacity, high stiffness, and good stability. The composite pipeline is filled with concrete between itself and the rock mass, so that the composite pipeline and the rock mass can share the load. Studs prevent local buckling of the inner and outer steel plates, while improving the synergistic working ability of the inner and outer steel plates and the sandwich concrete.

[0024] 3) Low cost

[0025] Large-diameter double-steel-plate concrete composite pipelines based on the load balance method utilize prestressed struts to apply external pressure to the pipeline in advance, thereby offsetting part of the water pressure inside the pipeline, reducing the load effect on the pipeline, effectively reducing the thickness of the steel plates and the strength of the steel, saving material usage, reducing project costs, and achieving good economic benefits.

[0026] Overall, the large-diameter double-steel-plate concrete composite pipeline based on the load balance method adopts a double-steel-plate concrete composite structure, which has advantages such as high load-bearing capacity, high rigidity, and good stability. The composite pipeline is filled with concrete between itself and the rock mass, so that the composite pipeline and the rock mass share the load. Prestressed struts are used to apply external pressure to the pipeline in advance, thereby offsetting part of the water pressure inside the pipeline, reducing the load effect of the pipeline, effectively reducing the thickness of the steel plate and the strength of the steel, saving material usage, reducing project costs, and having good economic benefits. Attached Figure Description

[0027] Figure 1 This is an overall schematic diagram of a large-diameter double-steel-plate concrete composite pipe based on the load balance method of the present invention.

[0028] Figure 2 This is a schematic cross-sectional view of a large-diameter double-steel-plate concrete composite pipe based on the load balance method of the present invention.

[0029] Figure 3 This is a schematic diagram of the cross-section of the second type of large-diameter double-steel-plate concrete composite pipe based on the load balance method of the present invention. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0032] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0033] In the description of this application, it should be noted that the terms "upper" and "lower" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product is usually placed during use. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0034] like Figures 1-3 As shown, the present invention provides a large-diameter double steel plate concrete composite pipe based on the load balance method, which is assembled from several double steel plate concrete pipe sections 1 along the axial direction, and an external pressure application structure is provided on the outside of some or all of the double steel plate concrete pipe sections 1.

[0035] This invention applies an external pressure to the double-steel-plate concrete pipe section 1 through the external pressure application structure, which is opposite to the direction of the water pressure inside the pipe. This offsets part of the water pressure inside the pipe, reduces the load effect on the pipeline, and achieves load balance. It effectively reduces the thickness of the steel plate and the strength of the steel, saves material usage, reduces project costs, and has good economic benefits.

[0036] In this invention, specifically, the external pressure application structure can pre-apply external pressure to the combined pipeline before its installation, and the direction of the external pressure is the radial direction of the pipeline.

[0037] One embodiment of the present invention, referred to Figure 2 The external pressure application structure includes a concrete lining 3 and multiple prestressed struts 8. The concrete lining 3 fills the space between the double-steel-plate concrete pipe section 1 and the rock mass 2. In this invention, it is cast-in-place, and the material can be ordinary concrete, high-strength concrete, recycled concrete, or self-compacting concrete to meet the different performance requirements of concrete in actual engineering projects. One end of each prestressed strut 8 is connected to the outer wall of the double-steel-plate concrete pipe section 1, and the other end is anchored inside the concrete lining 3.

[0038] In this embodiment, on the one hand, by filling concrete between the combined pipe and the rock mass 2, the combined pipe and the rock mass 2 are subjected to the same force. On the other hand, the prestressed struts 8 apply external pressure to the combined pipe to offset part of the water pressure inside the pipe, reduce the load effect of the pipe, effectively reduce the thickness of the steel plate and the strength of the steel, and save material usage.

[0039] In one embodiment of the present invention, the length direction of the prestressed struts 8 is consistent with the radial direction of the combined pipe, and the prestressed struts 8 are arranged at equal intervals along the circumferential and axial directions of the combined pipe. For example, in the example shown in the figure, eight prestressed struts 8 are distributed on a single circumference.

[0040] In this embodiment, the prestressed strut 8 is arranged in such a way that the force is more evenly distributed.

[0041] In one embodiment of the present invention, the length of the double-steel plate concrete pipe 1 is 2-4m, the inner diameter is not less than 8m, and the outer diameter is not less than 10m. The thickness of the concrete lining 3 is not less than 100mm. The length of the prestressed strut (8) is not greater than half the thickness of the concrete lining 3.

[0042] In one embodiment of the present invention, the double-steel-plate concrete pipe section 1 includes an outer steel pipe or an arc-shaped outer steel plate 4, an inner steel pipe or an arc-shaped inner steel plate 5, and a sandwich concrete 7, which fills the space between the outer steel pipe or arc-shaped outer steel plate 4 and the inner steel pipe or arc-shaped inner steel plate 5. When an arc-shaped outer steel plate and an arc-shaped inner steel plate are used, the arc-shaped outer steel plate and the arc-shaped inner steel plate are spliced ​​together in the circumferential direction to form a pipe section.

[0043] In this embodiment, a double-steel-plate concrete composite structure is adopted, which has advantages such as high load-bearing capacity, high stiffness, and good stability. The outer steel plate replaces the reinforcing steel in the reinforced concrete and can also serve as a formwork for pouring concrete, eliminating the need for formwork erection and dismantling, resulting in a simple structure and convenient construction. The inner and outer steel plates and the sandwiched concrete mutually constrain each other, with the concrete effectively preventing the steel plate from becoming unstable and the steel plate preventing brittle failure of the concrete. Simultaneously, an external pressure application structure is provided on the outside of the composite pipeline of this invention. This pressure application structure pre-applies an external pressure to the composite pipeline in the opposite direction to the internal water pressure, thereby offsetting part of the internal water pressure and reducing the load effect on the pipeline.

[0044] In one embodiment of the present invention, the interlayer concrete 7 is poured in a precast or cast-in-place manner. The interlayer concrete 7 is high-strength concrete, recycled concrete, self-compacting concrete, fiber-reinforced concrete (FRC), reactive powder concrete (RPC), or ultra-high performance concrete (UHPC). The inner wall of the outer steel pipe or arc-shaped outer steel plate 4 and / or the outer wall of the inner steel pipe or arc-shaped inner steel plate 5 are provided with studs 6, which are arranged in a square or quincunx pattern.

[0045] In this embodiment, considering the actual weight of the pipeline unit, as well as the geographical environment, road conditions, and transportation and hoisting conditions of the actual project, the casting method is selected as precast or cast-in-place to improve transportation efficiency. Specifically, self-compacting concrete has high fluidity, reactive powder concrete (RPC) has good toughness, and ultra-high performance concrete (UHPC) has good durability, etc., to meet the different performance requirements of concrete in actual projects.

[0046] The arrangement of the studs 6 prevents local buckling of the outer steel pipe or curved outer steel plate 4 and the inner steel pipe or curved inner steel plate 5, while improving the cooperative working ability of the outer steel pipe or curved outer steel plate 4 and the inner steel pipe or curved inner steel plate 5 with the sandwich concrete 7.

[0047] One embodiment of the present invention, such as Figure 3 As shown, the external pressure application structure is a concrete lining 3, without prestressed struts 8. The concrete lining 3 is expansive concrete, which fills the space between the double steel plate concrete pipe section 1 and the rock mass 2.

[0048] In this embodiment, there is no need to install prestressed struts 8. Instead, the properties of expansive concrete 9 are directly utilized to make the reaction force provided by the rock mass 2 become an external pressure opposite to the water pressure inside the combined pipeline. Compared with the scheme of installing prestressed struts 8, this embodiment can effectively control internal cracks in the concrete lining and improve the seismic resistance of the structure.

[0049] In one embodiment of the present invention, the inner diameter of the combined pipeline is not less than 8m and the outer diameter is not less than 10m. The self-stress of the expansive concrete 9 is not less than 0.2MPa and not less than the design critical external pressure of the double steel plate concrete pipe section 1.

[0050] In one embodiment of the present invention, the double steel plate concrete pipe section 1 is replaced with a pure steel pipe section or a hollow steel pipe concrete pipe section.

[0051] This embodiment uses a steel structure, which has high strength, good impermeability, and a short construction period, but it has problems such as low stiffness and large deformation. Hollow steel tube concrete structures, on the other hand, are characterized by high load-bearing capacity and good plasticity, but their construction is complex and the pouring quality is poor. In actual projects, the choice can be made based on conditions and requirements.

[0052] In summary, this invention discloses a large-diameter double-steel-plate concrete composite pipeline based on the load balance method. Its key feature is the pre-application of an external pressure opposite to the internal water pressure to the composite pipeline, thereby offsetting part of the internal water pressure and reducing the pipeline's operating load. The composite pipeline is assembled in axial segments, with adjacent segments welded together. A concrete lining fills the space between the composite pipeline and the rock mass. This invention employs a double-steel-plate concrete composite structure, which offers advantages such as high load-bearing capacity, high stiffness, and good stability. The concrete filling between the composite pipeline and the rock mass allows for shared load-bearing between the pipeline and the rock mass. Pre-stressed struts apply external pressure to the pipeline, offsetting part of the internal water pressure and reducing the pipeline's operating load. This effectively reduces steel plate thickness and steel strength, saving material usage and lowering project costs. It can be widely applied in the field of pressure pipelines for pumped storage power stations, possessing significant engineering practical value and socio-economic benefits.

[0053] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A large-diameter double-steel-plate concrete composite pipe based on the load balance method, comprising several double-steel-plate concrete pipe sections (1) assembled axially, characterized in that, An external pressure applying structure is provided outside some or all of the double steel plate concrete pipe section (1). The external pressure applying structure applies an external pressure to the double steel plate concrete pipe section (1) in the opposite direction to the water pressure inside the pipe, so as to offset part of the water pressure inside the pipe. The external pressure application structure includes a concrete lining (3) and multiple prestressed struts (8); the concrete lining (3) fills the space between the double steel plate concrete pipe section (1) and the rock mass (2); one end of each prestressed strut (8) is connected to the outer wall of the double steel plate concrete pipe section (1), and the other end is anchored inside the concrete lining (3); the length direction of the prestressed strut (8) is consistent with the radial direction of the combined pipe, and the prestressed struts (8) are evenly spaced along the circumferential and axial directions of the combined pipe; The double-steel-plate concrete pipe section (1) includes: Outer steel pipe or arc-shaped outer steel plate (4); Inner steel pipe or arc-shaped inner steel plate (5); The interlayer concrete (7) is filled between the outer steel pipe or arc-shaped outer steel plate (4) and the inner steel pipe or arc-shaped inner steel plate (5). When arc-shaped outer steel plate and arc-shaped inner steel plate are used, the arc-shaped outer steel plate and arc-shaped inner steel plate are spliced ​​into pipe sections along the circumferential direction. The interlayer concrete (7) is poured in a precast or cast-in-place manner. The interlayer concrete (7) is high-strength concrete, recycled concrete, self-compacting concrete, fiber-reinforced concrete, active powder concrete or ultra-high performance concrete. The inner wall of the outer steel pipe or arc-shaped outer steel plate (4) and / or the outer wall of the inner steel pipe or arc-shaped inner steel plate (5) are provided with studs (6). The studs (6) are arranged in a square or quincunx pattern. The concrete lining (3) is cast in place, and the concrete lining (3) is ordinary concrete, high-strength concrete, recycled concrete or self-compacting concrete. The length of the double steel plate concrete pipe section (1) is 2-4m, the inner diameter is not less than 8m, the outer diameter is not less than 10m, the thickness of the concrete lining (3) is not less than 100mm, and the length of the prestressed strut (8) is not greater than half the thickness of the concrete lining (3).

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