A drainage blind drain system

Abstract

The utility model provides a blind drainage system, belongs to blind drainage technical field, the blind drainage system of the utility model, including drainage ditch structure and sand mat layer, sand mat layer is used for reinforcing for the earth embankment foundation, can also include a plurality of water collecting well and monitoring system, is provided with multilayer filter structure in drainage ditch structure, is used for filtering the particle impurity in water, multilayer filter structure includes first filter layer, second filter layer and intermediate filter layer. Through setting sand mat layer in the top of drainage ditch structure, can reinforce the earth embankment foundation, effectively enhances the earth embankment foundation strength, prevents uneven settlement, improves overall stability, in addition, through setting multilayer filter structure, makes the water in the soil enter drainage system after multistage filtration, can significantly improve the filtering effect, prevents the fine particle soil in water from blocking drainage system, is further favorable to improving the drainage efficiency of drainage system, can be applicable to the filtration of different soil quality, and the adaptability is stronger.

Description

Technical Field

[0001] This utility model belongs to the field of drainage blind ditch technology, and specifically relates to a drainage blind ditch system. Background Technology

[0002] Large-scale artificial hill construction is an important engineering form in modern urban construction and ecological restoration, such as landscape hill creation and comprehensive utilization of waste soil and rock. These artificial hills are huge in size and will exert a huge load on the underlying foundation soil. At the same time, a large amount of seepage water will accumulate in the hill, causing the original foundation soil to soften, reduce its bearing capacity, and even trigger engineering problems such as landslides and instability. Therefore, it is necessary to install a drainage blind ditch system to drain the seepage water from the hill.

[0003] However, the existing blind drainage system has many shortcomings:

[0004] 1. Inadequate foundation treatment: The lack of an effective foundation reinforcement layer can easily lead to uneven settlement;

[0005] 2. Poor filtration effect: Geotextile alone has poor filtration effect, and fine soil particles can easily enter the drainage system, causing blockage.

[0006] 3. Rapid decline in drainage efficiency: Due to soil entering the drainage system, the drainage system becomes clogged, and the drainage capacity decreases significantly after a period of use.

[0007] Especially in the case of soft foundation conditions, traditional blind drain structures often lead to drainage system failure due to foundation settlement. Utility Model Content

[0008] In order to improve the strength of the construction foundation, prevent soil settlement, and enhance the filtration effect of the drainage system to prevent blockage, this utility model provides a drainage blind ditch system.

[0009] The technical solution of this utility model is as follows:

[0010] A drainage blind drain system, comprising:

[0011] A drainage ditch structure is used to be set at the junction of foundation soil and pile soil. The drainage ditch structure is equipped with a multi-layer filter structure to filter particulate impurities in the water.

[0012] A sand cushion layer is laid on top of the drainage ditch structure to reinforce the soil foundation;

[0013] The multi-layer filtration structure includes:

[0014] The first filter layer is disposed on the inner wall of the blind ditch and at the upper opening of the drainage ditch structure.

[0015] The second filter layer is disposed inside the first filter layer and forms a drainage path within the second filter layer;

[0016] An intermediate filter layer is filled between the first filter layer and the second filter layer.

[0017] Furthermore, the second filter layer is provided with a tool-type template inside to support the second filter layer in forming a drainage path, so that the second filter layer fits tightly with the intermediate filter layer.

[0018] Furthermore, the tool-type template is filled with a crushed stone drainage layer, which is composed of granite crushed stone with a particle size of 20-40mm and a thickness of 300-500mm.

[0019] Furthermore, the first filter layer has a basis weight of 200-400 g / m³. 2 Polyester needle-punched geotextile; and / or,

[0020] The second filter layer has a basis weight of 150-300 g / m³. 2 Polypropylene woven geotextile; and / or,

[0021] The intermediate filter layer is medium-coarse sand with a particle size of 0.25-0.5mm and a uniformity coefficient Cu≤5, and a thickness of 150-200mm.

[0022] Furthermore, the drainage ditch structure includes:

[0023] Main blind drain, which is used to be set at the edge and / or catchment area of ​​the junction between the foundation soil and the embankment soil;

[0024] Branch blind drains are installed at the junction of the foundation soil and the embankment soil, and are connected to the main blind drain to form a mesh drainage ditch structure.

[0025] Both the main blind drain and the branch blind drains have trapezoidal cross-sections with outward-expanding openings.

[0026] Furthermore, a water-guiding structure is provided within the main blind drain, the water-guiding structure comprising:

[0027] A plurality of water guide pipes are arranged inside the first filter layer at a lower position and extend along the length of the main blind ditch. A plurality of drainage holes are provided on the water guide pipes, and a third filter layer is provided on the surface of the water guide pipes.

[0028] A connector for connecting the ends of two adjacent water pipes.

[0029] Furthermore, the drainage blind ditch system also includes several water collection wells, which are located at the connection between the main blind ditch and the branch blind ditch, and the bottom of the water collection wells extends downward into the foundation soil.

[0030] Furthermore, the drainage blind ditch system also includes a monitoring system, which includes:

[0031] A water level sensor is installed inside the water collection well;

[0032] A data acquisition unit is used to collect data from water level sensors.

[0033] A remote transmission device used to transmit collected data to a remote terminal.

[0034] Furthermore, the sand cushion layer uses medium-coarse sand with a particle size of 0.5-2mm, a thickness of 800-1000mm, and a compaction degree of not less than 93%.

[0035] Furthermore, a geogrid reinforcement layer is provided on top of the sand cushion layer.

[0036] The beneficial effects of this utility model are as follows:

[0037] This utility model discloses a drainage blind ditch system. By setting a sand cushion layer on top of the drainage ditch structure, the soil foundation can be reinforced, effectively enhancing the strength of the soil foundation. This makes the original foundation soil less prone to uneven settlement, improving overall stability and extending the service life of the system. In addition, by setting a multi-layer filtration structure within the drainage ditch structure, water in the soil is filtered through multiple stages before entering the drainage system, which can significantly improve the filtration effect, prevent fine soil particles in the water from clogging the drainage system, and further improve the drainage efficiency of the drainage system. It can be used for filtration of different soil types and has strong adaptability. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the plan layout of a drainage blind ditch system according to an embodiment of this utility model;

[0039] Figure 2 This is a cross-sectional schematic diagram of a drainage blind ditch system according to an embodiment of the present utility model;

[0040] Figure 3 This is a schematic diagram of the cross-sectional structure of the main blind drain in an embodiment of this utility model;

[0041] Figure 4 This is a schematic diagram of the connection between the water pipe and the connector in an embodiment of this utility model;

[0042] Figure 5 This is a schematic diagram of the cross-sectional structure of the branch blind drain in this embodiment of the present invention;

[0043] Figure 6 This is a partially enlarged schematic diagram of the sand cushion layer, water collection well, and branch blind ditch structure in an embodiment of this utility model.

[0044] In the diagram: 1. Foundation soil; 2. Sand cushion layer; 301. First filter layer; 302. Second filter layer; 303. Intermediate filter layer; 4. Tool-type formwork; 5. Crushed stone drainage layer; 601. Main blind drain; 602. Branch blind drain; 701. Water pipe; 702. Connector; 8. Sump; 9. Geogrid reinforcement layer. Detailed Implementation

[0045] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of the present invention will become clearer from the following description and claims. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the present invention.

[0046] Example:

[0047] refer to Figures 1 to 6 The drainage blind ditch system provided in this embodiment is not only suitable for large-scale artificial hill construction projects, but also for engineering fields such as roadbed drainage, slope drainage, and site drainage under soft foundation conditions. It has a wide range of application value. It includes a drainage ditch structure and a sand cushion layer 2, and may also include several water collection wells 8 and a monitoring system (not shown).

[0048] The drainage ditch structure is set at the junction of the foundation soil 1 and the pile soil. The drainage ditch structure is equipped with a multi-layer filter structure to filter particulate impurities in the water.

[0049] Several water collection wells 8 are installed at the connection between the main blind ditch 601 and the branch blind ditch 602, with the bottom of the water collection wells 8 extending downwards into the foundation soil 1. The water collection wells 8 work in conjunction with the drainage ditch structure to temporarily store water that the drainage ditch structure cannot drain in time, preventing the water pressure inside the mountain from becoming too high suddenly and buying time for subsequent drainage. In addition, the silt carried by the water flow will naturally settle in the water collection wells 8, preventing it from directly entering the downstream pipes and causing blockages.

[0050] Sand cushion layer 2 is laid on top of the drainage ditch structure to reinforce the soil foundation. Sand cushion layer 2 uses medium-coarse sand with a particle size of 0.5-2mm and well-graded quartz sand (uniformity coefficient Cu>10) with a permeability coefficient of not less than 1×10⁻⁶. -3The sand cushion layer has a compaction rate of cm / s, which has a good anti-settlement effect. The laying thickness is 800-1000mm, preferably 1000mm. The compaction degree is not less than 93%. The top of the sand cushion layer 2 is provided with a geogrid reinforcement layer 9, which can improve the bearing capacity and enhance the stability of the sand cushion layer 2. In actual construction, the parameters of the sand cushion layer 2 can be adjusted according to different foundation conditions, and it has wide applicability.

[0051] The multi-layer filtration structure includes: a first filter layer 301, a second filter layer 302, and an intermediate filter layer 303.

[0052] The first filter layer 301 is installed on the inner wall and upper opening of the blind ditch of the drainage ditch structure. The first filter layer 301 has a basis weight of 200-400 g / m³. 2 Polyester needle-punched geotextile, preferably 300g / m 2 Polyester needle-punched geotextile has good water permeability and the ability to intercept fine particles.

[0053] The second filter layer 302 is disposed inside the first filter layer 301 and forms a drainage path within the second filter layer 302. The second filter layer 302 has a basis weight of 150-300g / m³. 2 Polypropylene woven geotextile, preferably 200g / m 2 The polypropylene woven geotextile has a higher density and better filtration accuracy in the second filter layer 302 compared to the first filter layer 301. The first filter layer 301 filters larger particulate impurities, while the second filter layer 302 filters smaller particulate impurities, thus achieving a layered filtration effect for seepage water.

[0054] The intermediate filter layer 303 is filled between the first filter layer 301 and the second filter layer 302. The intermediate filter layer 303 is medium-coarse sand with a particle size of 0.25-0.5mm and a non-uniformity coefficient Cu≤5. The thickness is 150-200mm. Since the cross-section of the blind ditch of the drainage ditch structure is trapezoidal and the cross-section of the tool template 4 is generally rectangular, the thickness of the intermediate filter layer 303 at different positions is not uniform. Therefore, the actual thickness of the intermediate filter layer 303 depends on the size of the blind ditch of the drainage ditch structure and the size of the tool template 4.

[0055] The monitoring system includes a water level sensor, a data acquisition unit, and a remote transmission device. The system can monitor the water level in the collection well 8 in real time, which is an important data point for assessing the stability of the mountain. If the water level is too high for a long period of time, it means that the risk of landslide is increasing, and it can remind staff to deal with it in time.

[0056] The water level sensor is installed inside the water collection well 8. The data acquisition device is used to collect the data from the water level sensor, and the remote transmission device is used to transmit the collected data to a remote terminal. Staff can view the water level information in real time on the remote terminal and obtain risk signals in a timely manner.

[0057] In a preferred embodiment, a tool-type template 4 is provided inside the second filter layer 302 to support the second filter layer 302 and form a drainage path, so that the second filter layer 302 fits tightly with the intermediate filter layer 303. This allows the second filter layer 302 to be flat and taut against the entire inner surface of the intermediate filter layer 303, effectively preventing surrounding soil particles from entering the water pipe 701 with the water flow, thus improving the filtration effect of the second filter layer 302. The tool-type template 4 is filled with a gravel drainage layer 5, which is made of granite gravel with a particle size of 20-40mm and a thickness of 300-500mm. The thickness of the gravel drainage layer 5 is determined according to the height of the tool-type template 4, and preferably can be 400mm.

[0058] As a preferred embodiment, the drainage ditch structure includes: a main blind ditch 601 and branch blind ditches 602.

[0059] The main blind drain 601 is used to be set at the edge and / or catchment area where the foundation soil 1 and the pile soil meet, so that water can be quickly discharged from the soil.

[0060] Branch blind drains 602 are used to be set at the junction of the foundation soil 1 and the pile soil. After connecting with the main blind drain 601, they form a mesh drainage ditch structure. Preferably, a branch blind drain 602 can be set at a spacing of about 20 meters, which helps to improve the water guiding and drainage capacity of the drainage ditch structure.

[0061] Both the main blind drain 601 and the branch blind drain 602 have trapezoidal cross-sections with outward expansion, which facilitates construction. The main blind drain 601 can be set with a depth of 0.7m and a bottom width of 0.7m; the branch blind drain 602 can be set with a depth of 0.5m and a bottom width of 0.5m. A height difference is formed between the branch blind drain 602 and the main blind drain 601 so that the water flow in the branch blind drain 602 can smoothly enter the main blind drain 601.

[0062] As a preferred embodiment, the main blind drain 601 is provided with a water guiding structure, which includes: a plurality of water guiding pipes 701 and connectors 702.

[0063] Several water guide pipes 701 are disposed inside the first filter layer 301 at a lower position and extend along the length of the main blind drain 601. Several drainage holes are provided on the water guide pipes 701. The diameter of the water guide pipes 701 is 110mm and the opening ratio is 3-5%, preferably 4%, so that the water flow can quickly enter the water guide pipes 701 without affecting the strength of the water guide pipes 701. A third filter layer (not shown) is provided on the surface of the water guide pipes 701. The third filter layer covers the surface of the water guide pipes 701 and filters the water flow again, further improving the filtration effect and preventing the drainage pipe from being blocked.

[0064] The connector 702 is used to connect the ends of two adjacent water pipes 701 so that several water pipes 701 form a continuous drainage pipeline to drain the seepage water out of the hill.

[0065] The present invention will be further described below with reference to specific embodiments:

[0066] A large-scale artificial hill landscape project has a height of approximately 42 meters and a base area of ​​about 40,000 square meters. The hill is mainly composed of cohesive soil and sandy soil. The underlying original foundation soil 1 is a weak silty clay layer, which requires foundation treatment and drainage design.

[0067] The construction process specifically includes the following steps:

[0068] S1. Foundation treatment: Level and compact the original foundation soil.

[0069] S2. Drainage excavation: Excavate a drainage trench on the sand cushion layer 2.

[0070] S3. Laying the first filter layer 301: using 300g / m 2 Polyester needle-punched geotextile.

[0071] S4. Fill the intermediate filter layer 303: 200mm thick, sand particle size 0.25-0.5mm, spread evenly and gently compact.

[0072] S5. Lay the second filter layer 302: using 200g / m 2 Polypropylene woven geotextile.

[0073] S6. Installation tool-type template 4: It is made of square steel and galvanized iron sheet.

[0074] S7. Lay a crushed stone drainage layer 5: 400mm thick, 20-40mm granite crushed stone.

[0075] S8. Install the 701 water pipe system: Use 110mm diameter porous HDPE pipe with an opening rate of 4%.

[0076] S9. Backfill with crushed stone to the design elevation, and finally seal with geotextile.

[0077] S10. Construction of Sand Cushion 2: Lay a 1000mm thick sand cushion 2, using medium-coarse sand with a particle size of 0.5-2mm, and compact it in layers to a compaction degree of more than 93%. Lay a geogrid reinforcement layer 9 on the sand cushion 2.

[0078] Implementation results:

[0079] After the blind drain system was applied in this project and underwent a rainy season, monitoring data showed that:

[0080] Drainage efficiency is improved by more than 45%, blind ditch blockage rate is reduced by 65%, the moisture content of the original foundation soil is kept within a safe range, the stability of the hill is significantly improved, and uneven settlement is controlled within the allowable range.

[0081] As can be seen from the above implementation results, the drainage blind ditch system of this utility model is not easy to clog, has good drainage efficiency, and has a good anti-settlement effect.

[0082] The above description is only a description of the preferred embodiment of the present utility model and is not intended to limit the scope of the present utility model in any way. Any changes or modifications made by those skilled in the art based on the above disclosure shall fall within the protection scope of the claims.

Claims

1. A drainage blind ditch system, characterized in that, include: A drainage ditch structure is provided at the junction of the foundation soil (1) and the pile soil. The drainage ditch structure is provided with a multi-layer filter structure for filtering particulate impurities in the water. Sand cushion layer (2), which is used to lay on top of the drainage ditch structure to reinforce the soil foundation; The multi-layer filtration structure includes: The first filter layer (301) is disposed on the inner wall of the blind ditch and at the upper opening of the drainage ditch structure; The second filter layer (302) is disposed inside the first filter layer (301) and forms a drainage path within the second filter layer (302); An intermediate filter layer (303) is filled between the first filter layer (301) and the second filter layer (302).

2. The drainage blind ditch system as described in claim 1, characterized in that, The second filter layer (302) is provided with a tool-type template (4) inside, which is used to support the second filter layer (302) to form a drainage path so that the second filter layer (302) and the intermediate filter layer (303) fit tightly together.

3. The drainage blind ditch system as described in claim 2, characterized in that, The tool-type template (4) is filled with a crushed stone drainage layer (5), which is granite crushed stone with a particle size of 20-40mm and a thickness of 300-500mm.

4. The drainage blind ditch system as described in claim 1, characterized in that, The first filter layer (301) has a basis weight of 200-400 g / m³. 2 Polyester needle-punched geotextile; and / or, The second filter layer (302) has a basis weight of 150-300 g / m³. 2 Polypropylene woven geotextile; and / or, The intermediate filter layer (303) is medium-coarse sand with a particle size of 0.25-0.5mm and a non-uniformity coefficient Cu≤5, and a thickness of 150-200mm.

5. The drainage blind ditch system as described in claim 1, characterized in that, The drainage ditch structure includes: Main blind drain (601), the main blind drain (601) is used to be set at the edge and / or water catchment area at the junction of the foundation soil (1) and the pile soil; Branch blind drain (602), the branch blind drain (602) is used to be set at the junction of the foundation soil (1) and the pile soil, and after being connected with the main blind drain (601), it forms a mesh drainage ditch structure; The cross-sections of the main blind drain (601) and the branch blind drain (602) are both trapezoidal structures with outwardly expanding openings.

6. The drainage blind ditch system as described in claim 5, characterized in that, The main blind drain (601) is provided with a water guiding structure, which includes: A plurality of water guide pipes (701) are disposed in the lower part of the first filter layer (301) and extend along the length of the main blind ditch (601). A plurality of drainage holes are provided on the water guide pipes (701), and a third filter layer is provided on the surface of the water guide pipes (701). A connector (702) is used to connect the ends of two adjacent water pipes (701).

7. The drainage blind ditch system as described in claim 5, characterized in that, The drainage blind ditch system also includes several collection wells (8), which are located at the connection between the main blind ditch (601) and the branch blind ditch (602), and the bottom of the collection wells (8) extends downward into the foundation soil (1).

8. The drainage blind ditch system as described in claim 7, characterized in that, The drainage blind ditch system also includes a monitoring system, which includes: A water level sensor is installed inside the water collection well (8); A data acquisition unit is used to collect data from water level sensors. A remote transmission device used to transmit collected data to a remote terminal.

9. The drainage blind ditch system as described in claim 1, characterized in that, The sand cushion layer (2) uses medium-coarse sand with a particle size of 0.5-2mm, with a thickness of 800-1000mm and a compaction degree of not less than 93%.

10. The drainage blind ditch system as described in claim 1, characterized in that, A geogrid reinforcement layer (9) is provided on top of the sand cushion layer (2).

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