Distributed water storage, seepage and drainage system
By designing a decentralized seepage drainage system on hardened roads, using the gravel layer and the seepage holes of the inspection well to form seepage space, the problem of urban waterlogging caused by the rapid collection of rainwater on hardened roads is solved, and the dispersion, peak cutting, flow reduction and dynamic expansion of rainwater are achieved, and the city's drainage capacity is improved.
Patent Information
- Application Number
- CN202422595431.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-28
- Publication Date
- 2025-08-15
- Estimated Expiration
- 2034-10-28
AI Technical Summary
On hardened roads, rapid collection of rainwater leads to frequent urban flooding. Traditional infiltration, stagnation and storage measures are rarely used on hardened urban roads, making it difficult to effectively absorb and regulate rainwater, resulting in a vicious cycle of urban flooding and drought.
A decentralized seepage drainage system is designed. By setting up gravel layers and inspection wells at the bottom of the soil structure of the hardened road, seepage holes are used to form seepage spaces, and water-separated non-woven fabrics are installed between the rainwater pipe and the gravel backfilling layer to form a dynamic capacity expansion effect of dispersion, peak cutting and flow reduction, so that rainwater on the hardened road does not form runoff, and seepage drainage is carried out through seepage holes and seepage holes.
65% to 75% of the rainwater on the hardened pavement have not formed runoff. Through infiltration and storage, the problem of urban waterlogging is solved, rapid outflow of rainwater is avoided, local absorption and absorption of cities is achieved, and vicious cycles of waterlogging and drought are reduced.
Smart Images
Figure CN223226772U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of municipal drainage, in particular to a decentralized seepage storage and drainage system. Background Art
[0002] Despite the ongoing rainwater and sewage diversion renovation projects in recent years, the pipeline network has become increasingly well-developed, with pipeline scale and standards continuously increasing. However, urban flooding continues to occur frequently during heavy rainstorms. The reasons for this are as follows: ① The impact of heavy rainfall; ② The high rate of hardening, resulting in large runoff, which rapidly collects rainwater in low-lying areas and downstream; ③ The low drainage capacity of river systems, high river levels, and severe uplift. The root cause of flooding is the rapid accumulation of rainwater. Due to the high rate of hardening, urban areas often quickly return to drought after flooding, creating a vicious cycle.
[0003] Currently, the construction of coastal cities has been ongoing for many years, and the construction concept of infiltration, retention, storage, purification, and utilization has been promoted for many years. Infiltration, retention, and storage engineering measures are mostly implemented in green belts, construction communities, and centralized water storage modules. However, sponge measures are rarely used in the vast number of urban hardened roads and hardened surfaces. Conventional municipal road greening is limited, sunken green spaces cannot effectively regulate and store water, and the use of permeable pavement can only alleviate peak runoff but cannot effectively absorb it.
[0004] Based on this, and considering the existence of a large number of inspection wells and rainwater outlets in the traditional rainwater pipe network design process, a decentralized infiltration and storage drainage structure was developed and designed through partial transformation of the inspection wells, thus solving the problem of on-site storage and regulation of hardened road rainwater. Utility Model Content
[0005] The utility model aims to solve the above problems and provides a decentralized seepage storage and drainage system.
[0006] The utility model is realized through the following technical scheme: a decentralized seepage storage and drainage system, including a soil structure, in which a plurality of inspection wells are installed, characterized in that a gravel layer is arranged at the bottom of the soil structure, a lower groove is arranged in the gravel layer, an inspection well is installed in the lower groove, and adjacent inspection wells are connected by rainwater pipes, the gravel layer includes a gravel cushion layer and a gravel backfill layer, wherein the gravel cushion layer is arranged at the bottom of the inspection well, the gravel backfill layer surrounds the inspection well and is arranged below the outer bottom of the rainwater pipe near the inspection well, a waterproof non-woven fabric is arranged at the boundary between the rainwater pipe and the gravel backfill layer, seepage holes are provided on the bottom and surrounding walls of each inspection well, a seepage storage space is formed by using the seepage holes, the height of the seepage holes is lower than the height of the rainwater pipe, backfill material is provided above the outer bottom of the rainwater pipe, the backfill material is compacted to the roadbed around the inspection well wall, and the inspection well mouth is flush with the roadbed.
[0007] Furthermore, the inspection well is rectangular, and sludge tanks are provided on both sides or one side of each inspection well. A rainwater outlet is provided at the upper end of the sludge tank, and the sedimentation tank is connected to the inspection well through a rainwater pipe.
[0008] Furthermore, the lower groove is 1 to 1.5 meters deep.
[0009] Furthermore, the diameter of the seepage holes is 20 mm, and the distance between adjacent seepage holes is 200 mm.
[0010] Furthermore, the crushed stone cushion layer is 30 cm thick and the particle size of the crushed stone is 25 to 30 mm.
[0011] Furthermore, the length of the waterproof non-woven fabric extends 40 cm beyond the junction surface of the rainwater pipe and the gravel layer, and is turned up 20 to 30 cm at the junction with the well wall.
[0012] Furthermore, the backfill material may be traditional soil.
[0013] The beneficial effect of the present invention is that the present invention utilizes the storage and infiltration principle of sponge city to dynamically expand the rainwater pipe system by "dispersing, cutting peaks and reducing flow", so that 65% to 75% of the rainwater on the hardened road surface does not form runoff or outflow, but is stored and infiltrated and discharged. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a structural diagram of the utility model;
[0015] Figure 2 This is a schematic diagram of the inspection well structure of the utility model;
[0016] Figure 3 This is a schematic diagram of the installation structure of the sedimentation tank of the utility model;
[0017] In the attached figure, 1 is an inspection well, 101 is a seepage storage space, 102 is a seepage hole, 2 is a rainwater pipe, 3 is a gravel layer, 4 is a waterproof non-woven fabric, 5 is a traditional material filling layer, 6 is a sedimentation tank, and 61 is a rainwater outlet. DETAILED DESCRIPTION
[0018] In order to make the purpose, technical solution and beneficial effects of the present invention more clear, the technical solution of the present invention is further described below in conjunction with embodiments.
[0019] like Figures 1 to 3The system, as shown, includes a decentralized seepage storage and drainage system consisting of a soil structure with several manholes installed within it. A gravel layer is installed at the bottom of the soil structure at the manholes. The gravel layer comprises a crushed stone cushion and a crushed stone backfill layer. The crushed stone cushion is located at the bottom of the manholes, while the backfill surrounds the manholes and extends below the outer bottom of the stormwater pipe near the manholes. The crushed stone cushion is 30 cm thick and has a particle size of 25 to 30 mm. Multiple recesses are provided within the gravel layer, each housing a manhole. The recesses are 1 to 1.5 meters deep, creating a localized concave structure for the manholes. The standard spacing between the manholes is designed to be 35 meters. For example, a conventional D1200 stormwater pipe with a 2.5-meter-wide manhole is designed with an extended manhole length of 3.5 meters and a storage depth of 1.4 meters. The designed effective seepage storage space W for the manholes is 12.25 cubic meters.
[0020] Adjacent inspection wells are connected by rainwater pipes. The rainwater pipes are backfilled with gravel backfill layer only near the inspection well end, and the remaining part uses traditional pipe sand and gravel foundation and traditional backfill. Water-proof non-woven fabric is set at the boundary between the rainwater pipe and the gravel backfill layer. The length of the water-proof non-woven fabric extends 40 cm from the joint surface of the rainwater pipe and the gravel backfill layer, and is turned up 20 to 30 cm at the junction with the well wall.
[0021] There are seepage holes on the bottom and surrounding walls of each inspection well to form a seepage storage space. The height of the seepage holes is lower than that of the rainwater pipes. The diameter of the seepage holes is 20mm, and the distance between adjacent seepage holes is 200mm. The effective seepage surface of the seepage storage space is approximately AS25.55 square meters, that is, the four side facades and one bottom surface below the bottom of the pipe.
[0022] Backfill material is provided above the outer bottom of the rainwater pipe. The backfill material can be traditional plain soil or special materials. The backfill material is compacted to the roadbed around the inspection well wall, and the inspection well mouth is flush with the roadbed.
[0023] The inspection well is rectangular. In order to improve the infiltration effect of the seepage space and ensure that the rainwater entering the pipeline is clean as much as possible, each inspection well is provided with a sedimentation tank on both sides or one side. A rainwater outlet is provided at the upper end of the sedimentation tank, and the sedimentation tank is connected to the inspection well through a rainwater pipe.
[0024] Taking Jinan's total rainwater control rate of 65% to 75% corresponding to a rainfall of 19.7 to 27.7 mm as an example, no outflow occurs. A single infiltration and storage well effectively controls an area of approximately 777 to 552 square meters of rainfall surface without forming runoff, corresponding to a 20-meter-wide road length of approximately 27.5 to 39 meters.
[0025] The calculated seepage volume of the inspection well in 48 hours should be greater than the seepage storage capacity (W) to avoid the long-term inability to infiltrate and discharge water, which affects the storage capacity. The seepage volume of the infiltration facility is calculated according to the formula Ws=α*K*J*As*ts, where α is the total coefficient and is between 0.5-0.6. K is the soil permeability coefficient and is 5.7*10-61m / s; J is the hydraulic slope and is 1; As is the permeability surface, unit: m 2 , calculated as 25.55m 2 ; ts is the infiltration time, unit: second. When used for regulation and storage, the time is less than 12 hours. When used for infiltration pools and infiltration wells, it is less than 72 hours. The infiltration volume of 48 hours in this case is about 15.09 cubic meters. Ws≥W is greater than the regulation and storage capacity.
[0026] Construction method:
[0027] The first step is to measure and lay out the lines, and excavate the trench (at the same time, deal with the unqualified pipes and inspection well foundations): Different from the traditional drainage pipe trench excavation, the depth of the traditional drainage pipe and the adjacent inspection well trench is basically the same. The depth of the inspection well trench in this design process is 1.0 to 1.5 meters deeper than the adjacent pipe foundation, forming a local "concave" at the inspection well.
[0028] Step 2: Backfill and compact the sand and gravel cushion layer: Unlike traditional drainage pipes, which use a uniform sand and gravel cushion layer, the pipe splicing section uses a traditional sand and gravel cushion layer for backfill and compaction. The inspection well location uses a crushed stone cushion layer with a thickness of 30cm and a crushed stone particle size of 25-30mm.
[0029] The third step is pipeline installation and layered backfill and compaction: pipeline splicing uses traditional socket-and-spigot rubber ring connection, and backfill material uses traditional plain soil or other backfill materials and is compacted symmetrically in layers to the designed roadbed, with each layer thickness not exceeding 20cm.
[0030] Step 4: Backfill and compaction around the inspection well. This part is divided into two parts. (1) For the infiltration and water storage area below the outer bottom of the pipe, use 25-30mm crushed stone to symmetrically backfill and compact to the outer bottom of the pipe. During the backfill and compaction process, it is strictly forbidden to control the gaps between the crushed stone and fine particles to ensure that the gaps of the crushed stone backfill are good. (2) For the area above the outer bottom of the pipe, use the same backfill material as the pipeline section, and backfill and compact to the roadbed in symmetrical layers.
[0031] To ensure sufficient porosity in the gravel backfill around the pipeline inspection well and to ensure the safety of the pipeline foundation, a waterproof non-woven fabric is used to separate the rainwater pipe from the gravel. The non-woven fabric extends 40 cm beyond the interface and is folded up 20 to 30 cm around the inspection well wall to ensure the effective seepage and storage of the reservoir.
[0032] Working process: During rainfall, surface runoff from the hardened road surface enters the sedimentation tank through the stormwater inlet for sedimentation. Relatively clean rainwater is discharged through the stormwater pipe into the inspection well. Under the regulation and storage function of the inspection well, rainwater is stored and seeps into the infiltration space. When the amount of rainwater is less than the effective storage capacity of the infiltration space, no flowing water forms in the pipe, and the rainwater is stored and seeps in situ. Rainwater exceeding the infiltration capacity gradually forms runoff and is discharged into the pipe, achieving decentralized regulation and localized disposal and discharge. When the rainfall stops, the runoff in the pipe stops for a period of time, and the rainwater stored in the inspection well is discharged through natural infiltration. Theoretically, the water in the infiltration space is drained within 48 hours, preventing the long-term storage and deterioration of rainwater and clearing the infiltration space for the next rainfall. This repetitive cycle works to achieve the localized absorption and disposal function of the sponge city.
[0033] This structure is mostly suitable for drainage areas with relatively low groundwater levels; or for the construction of seepage well pipelines in areas where the pipeline elevation is higher than the normal water level of the river.
[0034] Except for the technical features described in the specification, the remaining technical features are known to those skilled in the art.
Claims
1. A decentralized seepage storage and drainage system, comprising a soil structure with a plurality of inspection wells provided therein, characterized in that: A gravel layer is provided at the bottom of each inspection well, a lower groove is provided in the gravel layer, and an inspection well is installed in the lower groove. Adjacent inspection wells are connected by rainwater pipes. The gravel layer includes a gravel cushion layer and a gravel backfill layer, wherein the gravel cushion layer is provided at the bottom of the inspection well, the gravel backfill layer surrounds the inspection well and is provided below the outer bottom of the rainwater pipe near the inspection well, a waterproof non-woven fabric is provided at the boundary between the rainwater pipe and the gravel backfill layer, and seepage holes are provided at the bottom and surrounding walls of each inspection well, and seepage holes are used to form a seepage space. The height of the seepage holes is lower than the height of the rainwater pipe, and backfill material is provided above the outer bottom of the rainwater pipe. The backfill material is compacted to the roadbed around the inspection well wall, and the inspection well mouth is flush with the roadbed.
2. A decentralized seepage storage and drainage system according to claim 1, characterized in that: The inspection well is rectangular, and each inspection well is provided with a sedimentation tank on both sides or one side. The upper end of the sedimentation tank is provided with a rainwater outlet, and the sedimentation tank is connected to the inspection well through a rainwater pipe.
3. A decentralized seepage storage and drainage system according to claim 1, characterized in that: The lower groove is 1 to 1.5 meters deep.
4. A decentralized seepage storage and drainage system according to claim 1, characterized in that: The diameter of the seepage holes is 20 mm, and the distance between adjacent seepage holes is 200 mm.
5. A decentralized seepage storage and drainage system according to claim 1, characterized in that: The crushed stone cushion layer is 30cm thick and the particle size of the crushed stone is 25 to 30mm.
6. A decentralized seepage storage and drainage system according to claim 1, characterized in that: The length of the water-proof non-woven fabric extends 40 cm beyond the junction surface of the rainwater pipe and the gravel layer, and is turned up 20 to 30 cm at the junction with the well wall.
7. The decentralized seepage storage and drainage system according to claim 1, characterized in that: The backfill material is a traditional backfill material.