Double-wing concealed pipe device for drainage of unsaturated soil in farmland

Abstract

The present invention relates to the field of agricultural water and soil engineering technology, and is a double-wing concealed pipe device for drainage of unsaturated soil in farmland, wherein the structure of the frame is composed of two wing-shaped frames and two supporting frames, wherein the wing-shaped frame structure comprises a "<"-shaped frame and a "—"-shaped impermeable wing portion, wherein the "—"-shaped impermeable wing portion is fixedly connected to the lower end of the "<"-shaped frame and is arranged horizontally; the two wing-shaped frames are arranged symmetrically, and the heat-sealed bonding portion I at the upper end of the "<"-shaped frame of the two is bonded and fixed, and the heat-sealed bonding portion II provided at the lower end of the supporting frame is embedded in the embedded groove of the "—"-shaped impermeable wing portion and is bonded and fixed. The present invention can effectively slow down the phenomenon of water circumferential flow around the drainage concealed pipe, avoid secondary leakage at the bottom of the concealed pipe after water enters the concealed pipe, and can also keep the cross-sectional shape of the pipe from being deformed, effectively improve work efficiency, and has a reasonable structure, economy and practicality.

Description

Technical Field

[0001] The invention relates to the technical field of agricultural water and soil engineering, in particular to a concealed pipe device used for drainage of unsaturated soil in farmland. Background Art

[0002] Concealed pipe drainage is an important measure for suppressing and washing salt in the process of farmland salinization and alkali treatment. It is achieved by burying underground pipes and using irrigation water and rainwater to flush the saline-alkali soil layer above the pipes to remove excessive salt in the soil. At the same time, it controls the groundwater level at a certain depth to prevent salt from returning upward, thereby providing good soil conditions for plant growth. It is favored by people for its obvious treatment effect, short treatment cycle, and simple later maintenance and management. It has now developed into a relatively mature technical measure for improving saline-alkali land.

[0003] The traditional farmland underground pipe drainage design is based on the soil saturated flow theory, and the farmland underground pipe drainage system used in production practice also works under the saturated flow state. The drainage efficiency of traditional drainage underground pipes in unsaturated soil is not high, because under unsaturated soil conditions, the combined effect of atmospheric pressure in the underground pipe and matrix suction in the soil makes it difficult for soil moisture to automatically enter the underground pipe, and the moisture always flows around the underground pipe; only when the soil around the underground pipe reaches saturation, the moisture enters the underground pipe and is discharged.

[0004] In the current technology, the Chinese patent published: Wallless concealed pipe for drainage in unsaturated soil, patent number: ZL2019 2 2470191.9, is a wallless concealed pipe composed of a grid and an outer geotextile, the purpose of which is to reduce the resistance of water entering the concealed pipe, use the matrix suction of the geotextile to guide soil moisture into the concealed pipe, and achieve better drainage effect; its appearance structure is composed of three arched grids, and uses geotextile as a filter layer to separate the soil and the concealed pipe drainage space. However, in actual use, there are still some shortcomings, which cannot effectively slow down the phenomenon of water bypassing around the drainage concealed pipe, and cannot effectively prevent water from entering the concealed pipe and causing secondary leakage at the bottom of the concealed pipe.

[0005] In order to solve the problems of the above-mentioned farmland underground drainage concealed pipes being prone to bypass flow, secondary leakage at the bottom, and reduced work efficiency, the present invention has made a breakthrough improvement based on the existing technology. Summary of the invention

[0006] In order to solve the above technical problems, the purpose of the present invention is to provide a double-wing concealed pipe device for drainage of unsaturated soil in farmland, which can effectively slow down the circumference of water around the concealed drainage pipe, avoid secondary leakage at the bottom of the concealed pipe after the water enters the concealed pipe, and maintain the cross-sectional shape of the pipe without deformation, thereby effectively improving work efficiency, with a reasonable structure and economical and practical use.

[0007] The invention discloses a double-wing concealed pipe device for drainage of unsaturated soil in farmland, the structure of which includes a grid and an isolation layer, wherein the grid structure is composed of two wing-shaped grids and two supporting grids, wherein the wing-shaped grid structure includes a "<"-shaped grid and a "—"-shaped impermeable wing portion, the cross-sectional shape of the "<"-shaped grid is "<"-shaped, the cross-sectional shape of the "—"-shaped impermeable wing portion is "—"-shaped, the "—"-shaped impermeable wing portion is fixedly connected to the lower end of the "<"-shaped grid and is horizontally arranged; the structure of the "<"-shaped grid includes a longitudinal support rod I and a transverse support rod I, a plurality of longitudinal support rods I are cross-fixedly connected to the transverse support rod I at intervals, and holes are formed between the longitudinal support rods I and the transverse support rods I after connection; the ends and corners of the "<"-shaped grid are both provided with a heat-sealed bonding portion I; the structure of the "—"-shaped impermeable wing portion is a flat plate, and an embedding groove is provided on the flat plate;

[0008] The support grid structure comprises a longitudinal support rod II and a transverse support rod II, wherein a plurality of longitudinal support rods II and transverse support rods II are cross-fixedly connected at intervals, and holes are formed between the longitudinal support rods II and transverse support rods II after connection; heat-sealed bonding parts II are respectively provided at both ends of the support grid;

[0009] The two wing-shaped grids are arranged symmetrically on the left and right, and the heat-sealed adhesive portions I at the upper ends of the "<"-shaped grids of the two are bonded and fixed by a heat-sealing process, and the heat-sealed adhesive portions I at the lower ends of the "<"-shaped grids of the two are also bonded and fixed by a heat-sealing process; the heat-sealed adhesive portions I at the corner portions of the "<"-shaped grids of the two are respectively bonded and fixed to the heat-sealed adhesive portions II at the upper ends of a supporting grid by a heat-sealing process, and the heat-sealed adhesive portion II at the lower ends of the supporting grids is just embedded in the embedding groove of the "—"-shaped water-impermeable wing portion and is bonded and fixed by a heat-sealing process;

[0010] The isolation layer is arranged on the outer side of the assembled grid.

[0011] Preferably, the shape of the hole formed between the longitudinal support rod I and the transverse support rod I is square, circular, diamond or triangular; the shape of the hole formed between the longitudinal support rod II and the transverse support rod II is square, circular, diamond or triangular.

[0012] Preferably, the grid is made of PVC material, and the isolation layer is geotextile.

[0013] The structure of the present invention is a triangular-shaped grid drainage concealed pipe composed of two groups of PVC airfoil grids and two groups of PVC supporting grids; the outer surface of the pipe is wrapped with geotextile (non-woven fabric), and the geotextile is used as an isolation layer and filter layer between the pipe and the soil, which increases the porosity of the pipe wall and avoids pore blockage; wherein, the two groups of PVC airfoil grids and the two groups of PVC supporting grids are bonded together by PVC strips (the bonding surface height is 4-5mm), and the compressive properties of the triangular structure are used to well maintain the cross-sectional shape of the pipe, thereby well supporting the geotextile and preventing it from collapsing. The present invention refers to this concealed pipe structure as a triangular double-wing concealed pipe structure.

[0014] The wing-shaped grid and the supporting grid are made of hard PVC material, which can form large meshes, and the mesh shapes are rectangular, circular, triangular or diamond. The two sets of PVC wing-shaped grids and the two sets of PVC supporting grids are heat-sealed with PVC strips to finally form a triangular grid, and the triangular grid has strong compressive resistance. The wing-shaped grid and the supporting grid can be made at one time by the factory. The grid opening rate is about 90%, making the concealed pipe similar to the ratway structure. The size of the outer geotextile (non-woven fabric) matches the length and outer diameter circumference of the concealed pipe.

[0015] Working principle of the present invention:

[0016] The pipe wall of the traditional farmland underground drainage pipe only plays the role of supporting the soil pressure and ensuring that the drainage space in the pipe is not reduced; the present invention adopts a triangular grid structure to support the soil pressure outside the pipe, and uses geotextile (non-woven fabric) as an isolation layer and filter layer to isolate the drainage space of the pipe from the soil, which not only prevents soil from entering the pipe, but also improves the pipe's pressure resistance and maintains the shape of the triangular pipe; since the geotextile has good permeability, it can ensure that moisture enters the pipe, so the present invention eliminates the resistance of soil moisture entering the pipe to the greatest extent.

[0017] At the same time, in order to more effectively slow down the phenomenon of water circumferential flow around the drainage pipe and avoid secondary leakage at the bottom of the pipe after water enters the pipe, the present invention improves the cross-sectional form of the pipe on the basis of the wallless drainage pipe supported by the grid, increases the water circumferential flow resistance around the pipe with a triangular cross-section, and sets a watertight wing-shaped structure at the bottom of the pipe to form a wing-shaped pipe. In addition to the advantages of the wallless pipe in the prior art, such as large opening rate, good stability and good support for geotextiles, the triangular double-wing pipe intercepts the circumferential flow by using the wing-shaped structure (watertight wing part). When the flow direction of the matrix flow changes, the flow rate will decrease. The structure is stable and can intercept the circumferential flow, thereby forming local water accumulation and promoting drainage of the pipe, and preventing secondary leakage of water in the pipe. The double-wing pipe is connected and fixed by two grids covered with geotextiles through a heat-sealing process.

[0018] likeFigure 8 , Fig. 9 The figure shows the drainage capacity comparison between the triangular double-wing concealed pipe of the present invention (opening rate 85%, triangle side length 6.5cm) and the traditional circular cross-section concealed pipe (opening rate 85%, pipe diameter 5.5cm) under the same irrigation conditions (6 liters); the total wing length of the two concealed pipes is 10cm, and the specification of the single-layer non-woven fabric wrapped on the outer interface is 300g / ㎡. The experiment shows that under the same irrigation amount and external environment, the moisture content of the soil around the concealed pipe of the present invention is greater than the mass moisture content of the soil around the circular cross-section concealed pipe, indicating that the concealed pipe of the present invention has a large resistance to the bypass flow and generates more water accumulation; ultimately, the drainage capacity of the concealed pipe of the present invention is greater than that of the traditional circular cross-section concealed pipe.

[0019] Compared with the drainage concealed pipes currently used in production, the characteristics of the present invention are that the opening rate is increased, and the resistance of water flow entering the concealed pipe is greatly reduced. The present invention is supported by a triangular grid, the structure is stable, and the pipe section is not easily deformed. The outer interface grid is made of PVC strips heat-sealed and bonded, so that the present invention has the characteristics of simple and flexible processing. In addition, the present invention also has the advantage of being easy to mechanized.

[0020] The triangular shape structure of the concealed pipe provided by the present invention is formed by combining two groups of PVC wing-shaped grids and two groups of PVC supporting grids, and then wrapping a layer of geotextile on the outer layer, thus forming this triangular double-wing drainage concealed pipe structure. The structure utilizes the natural compressive strength of the triangular grid and the large porosity of the grid, so that the concealed pipe has the advantages of large pipe wall opening rate, good stability, good support for geotextile, and good maintenance of the cross-sectional shape of the pipe. It can effectively slow down the phenomenon of water flowing around the drainage concealed pipe, and avoid secondary leakage at the bottom of the concealed pipe after water enters the concealed pipe. It is a reasonable structure, economical and practical concealed pipe device for drainage of unsaturated soil in farmland. Therefore, developing a cheap and efficient infiltration integrated drainage pipe to form a composite pipe material that is easy to mechanize construction has important application value and broad prospects for promotion and application for improving the construction efficiency of concealed pipe engineering, improving the drainage effect and service life of concealed pipes. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the cross-sectional front view structure of Example 1 of the present invention.

[0022] Figure 2 for Figure 1 Schematic diagram of the cross-section main structure of the mid-wing-shaped grid.

[0023] Figure 3 for Figure 1 Schematic diagram of the three-dimensional structure of the mid-wing-shaped grid.

[0024] Figure 4 for Figure 1Schematic diagram of the three-dimensional structure of the isolation layer covering the outer side of the mid-wing-shaped grid.

[0025] Figure 5 for Figure 1 Schematic diagram of the cross-section main structure of the middle support grid.

[0026] Figure 6 for Figure 1 Schematic diagram of the three-dimensional structure of the central support grid.

[0027] Figure 7 for Figure 1 Schematic diagram of the three-dimensional structure of the isolation layer covering the outer side of the central supporting grid.

[0028] Figure 8 , Fig. 9 The drainage capacity of the triangular double-wing concealed pipe of the present invention (opening rate 85%, triangle side length 6.5cm) and the traditional circular cross-section concealed pipe (opening rate 85%, pipe diameter 5.5cm) under the same irrigation conditions (6 liters) is compared; the total wing length of the two concealed pipes is 10cm, and the specification of the single-layer non-woven fabric wrapped on the outer interface is 300g / ㎡. The experiment shows that under the same irrigation amount and external environment, the moisture content of the soil around the concealed pipe of the present invention is greater than the mass moisture content of the soil around the circular cross-section concealed pipe, indicating that the concealed pipe of the present invention has a large resistance to the bypass flow and generates more water accumulation; ultimately, the drainage capacity of the triangular double-wing concealed pipe of the present invention is greater than that of the traditional circular cross-section concealed pipe.

[0029] As shown in the figure: 1 is an isolation layer, 2 is a wing-shaped grid, 3 is a supporting grid, 4 is a heat-sealed bonding portion I, 5 is an upper end portion, 6 is a "<"-shaped grid, 7 is a folded corner portion, 8 is a lower end portion, 9 is an embedded groove, 10 is a "-"-shaped impermeable wing portion, 11 is a transverse support rod I, 12 is a longitudinal support rod I, 13 is a heat-sealed bonding portion II, 14 is a transverse support rod II, 15 is a longitudinal support rod II, and 16 is a hole. DETAILED DESCRIPTION

[0030] Embodiment 1:

[0031] Reference Figure 1-Figure 9, is a structural schematic diagram of an embodiment of the present invention, a double-wing concealed pipe device for drainage of unsaturated soil in farmland, the structure of which mainly includes a grid and an isolation layer 1, wherein the structure of the grid is composed of two groups of wing-shaped grids 2 and two supporting grids 3, wherein the wing-shaped grid 2 structure includes a "<"-shaped grid 6 and a "—"-shaped impermeable wing portion 10, the cross-sectional shape of the "<"-shaped grid 6 is "<"-shaped, the cross-sectional shape of the "—"-shaped impermeable wing portion 10 is "—"-shaped, and the "—"-shaped impermeable wing portion 10 is fixedly connected to the lower end of the "<"-shaped grid 6 and is arranged horizontally; the structure of the "<"-shaped grid 6 includes a longitudinal support rod Ⅰ11 and a transverse support rod Ⅰ12, and a plurality of longitudinal support rods Ⅰ12 are fixedly connected to the transverse support rod Ⅰ11 at intervals, and a hole is formed between the longitudinal support rods Ⅰ12 and the transverse support rods Ⅰ11 after connection; the end and the corner portion 7 of the "<"-shaped grid 6 are provided with a heat-sealed bonding portion Ⅰ4; the structure of the "—"-shaped impermeable wing portion 10 is a flat plate, and a groove 9 is provided on the flat plate;

[0032] The structure of the support grid 3 includes longitudinal support rods II15 and transverse support rods II14. A plurality of longitudinal support rods II15 and transverse support rods II14 are cross-fixed and connected at intervals, and holes 16 are formed between the longitudinal support rods II15 and transverse support rods II14 after connection; heat-sealed bonding parts II13 are respectively provided at both ends of the support grid 3;

[0033] The two wing-shaped grids 2 are arranged symmetrically on both sides, and the heat-sealed adhesive portions Ⅰ4 of the upper ends 5 of the "<"-shaped grids 6 of the two are bonded and fixed by a heat-sealing process, and the heat-sealed adhesive portions Ⅰ4 of the lower ends 8 of the "<"-shaped grids of the two are also bonded and fixed by a heat-sealing process; the heat-sealed adhesive portions Ⅰ4 of the corner portions 7 of the two "<"-shaped grids are respectively bonded and fixed with the heat-sealed adhesive portions Ⅱ13 of the upper ends of a supporting grid 3 by a heat-sealing process, and the heat-sealed adhesive portions Ⅱ13 provided at the lower ends of the supporting grids 3 are just embedded in the embedding grooves 9 of the "—"-shaped water-impermeable wing portions 10, and are bonded and fixed by a heat-sealing process;

[0034] The isolation layer 1 is arranged on the outer side of the assembled grid. The grid is made of PVC material, and the isolation layer 1 is geotextile.

[0035] The hole formed between the longitudinal support rod Ⅰ12 and the transverse support rod Ⅰ11 is square in shape; the hole formed between the longitudinal support rod Ⅱ15 and the transverse support rod Ⅱ14 is square in shape.

[0036] Embodiment 2:

[0037] Compared with the first embodiment, the present embodiment is different in that: the hole formed between the longitudinal support rod Ⅰ12 and the transverse support rod Ⅰ11 is circular in shape; the hole formed between the longitudinal support rod Ⅱ15 and the transverse support rod Ⅱ14 is circular in shape.

[0038] Embodiment 3:

[0039] Compared with the first embodiment, the present embodiment is different in that: the hole-shaped triangle is formed between the longitudinal support rod Ⅰ12 and the transverse support rod Ⅰ11; the hole-shaped triangle is formed between the longitudinal support rod Ⅱ15 and the transverse support rod Ⅱ14.

Claims

1. A double-wing concealed pipe device for drainage of unsaturated soil in farmland, characterized in that Its structure includes a grid and an isolation layer, wherein the grid structure is composed of two wing-shaped grids and two supporting grids, wherein the wing-shaped grid structure includes a "<"-shaped grid and a "—"-shaped impermeable wing portion, wherein the cross-sectional shape of the "<"-shaped grid is "<"-shaped, and the cross-sectional shape of the "—"-shaped impermeable wing portion is "—"-shaped, and the "—"-shaped impermeable wing portion is fixedly connected to the lower end of the "<"-shaped grid and arranged horizontally; the structure of the "<"-shaped grid includes a longitudinal support rod I and a transverse support rod I, wherein a plurality of longitudinal support rods I and transverse support rods I are cross-fixedly connected at intervals, and holes are formed between the longitudinal support rods I and the transverse support rods I after connection; the ends and corners of the "<"-shaped grid are both provided with a heat-sealed bonding portion I; the structure of the "—"-shaped impermeable wing portion is a flat plate, and an embedding groove is provided on the flat plate; The support grid structure comprises a longitudinal support rod II and a transverse support rod II, wherein a plurality of longitudinal support rods II and transverse support rods II are cross-fixedly connected at intervals, and holes are formed between the longitudinal support rods II and transverse support rods II after connection; heat-sealed bonding parts II are respectively provided at both ends of the support grid; The two wing-shaped grids are arranged symmetrically on the left and right, and the heat-sealed adhesive portions I at the upper ends of the "<"-shaped grids of the two are bonded and fixed by a heat-sealing process, and the heat-sealed adhesive portions I at the lower ends of the "<"-shaped grids of the two are also bonded and fixed by a heat-sealing process; the heat-sealed adhesive portions I at the corner portions of the "<"-shaped grids of the two are respectively bonded and fixed to the heat-sealed adhesive portions II at the upper ends of a supporting grid by a heat-sealing process, and the heat-sealed adhesive portions II at the lower ends of the supporting grids are just embedded in the embedding grooves of the "—"-shaped water-impermeable wing portions, and are bonded and fixed by a heat-sealing process; The isolation layer is arranged on the outer side of the assembled grid.

2. The double-wing concealed pipe device for drainage of unsaturated soil in farmland as claimed in claim 1, characterized in that The shape of the hole formed between the longitudinal support rod I and the transverse support rod I is square, circular, diamond or triangular; the shape of the hole formed between the longitudinal support rod II and the transverse support rod II is square, circular, diamond or triangular.

3. The double-wing concealed pipe device for drainage of unsaturated soil in farmland according to claim 1 or 2, characterized in that The grid is made of PVC material, and the isolation layer is geotextile.

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