Underground drainage side wall structure

Abstract

The utility model belongs to underground structure field, concretely is a kind of underground drainage side wall structure and. The structure includes inwardly projecting lug, outwardly projecting lug, downwardly extending water baffle, cohesive soil isolation layer, fine sand buffer layer, broken stone drainage layer, isolation geotextile and water collecting groove. Inwardly projecting lug slows down groundwater pressure and flow rate, outwardly projecting lug has the effect of weight and anti-floating, water baffle enhances anti-slippage stability, and cohesive soil isolation layer is covered on the top of outwardly projecting lug. Fine sand buffer layer is located between broken stone drainage layer and underground waterproof structure, and it buffers high flow rate turbulent flow; broken stone drainage layer drains groundwater, and two layers cooperate to reduce the risk of anti-floating. Water collecting groove is provided with grid holes on the side, to collect groundwater and discharge to municipal pipe network. The structure can cancel the structure waterproof plate by draining groundwater and releasing pressure, greatly reduce traditional anti-floating measures such as uplift pile and anchor rod, save underground structure investment, and is convenient for construction, with economy and practicability.

Description

Technical Field

[0001] This utility model belongs to the field of underground structures, specifically an underground drainage sidewall structure. Background Technology

[0002] Existing anti-buoyancy technologies for underground structures mainly rely on tension piles, tension anchors, and the structure's self-weight and overburden weight. Tension piles and tension anchors are widely used in underground engineering due to their high reliability. However, these traditional anti-buoyancy measures have some drawbacks:

[0003] In areas with high water levels, especially for underground structures without above-ground buildings, anti-buoyancy costs account for a very high proportion of the overall cost. Such measures only serve an anti-buoyancy function and cannot generate direct economic benefits, resulting in low return on investment and significant resource waste. Pull-out piles and anchors require additional construction time and are limited by geological conditions; for example, construction is difficult and costs surge in soft soil or high-water-level strata. Furthermore, while existing technologies can partially alleviate the anti-buoyancy problem by increasing the structure's self-weight or using backfill for weight-bearing, their application is limited by site conditions and load requirements. Therefore, there is an urgent need for a new structure that is simple, easy to construct, economical, and can effectively reduce the risk of buoyancy. Utility Model Content

[0004] To address the aforementioned problems, this invention provides an underground drainage sidewall structure. This structure is simple, reliably and effectively solves the buoyancy problem of basements, and is economical and easy to construct. It can be used for the exterior walls of building basements, integrated utility tunnels, sunken plazas, etc.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0006] An underground drainage sidewall structure includes: an inward-facing cantilever, an outward-facing cantilever, a downwardly extending water-retaining plate, a cohesive soil isolation layer, a fine sand buffer layer, a gravel drainage layer, an isolation geotextile, and a drainage trench; the inward-facing cantilever extends into the underground structure to reduce groundwater pressure and flow velocity, and the outward-facing cantilever extends outward from the underground structure and also serves as a weight-bearing and anti-buoyancy function; the water-retaining plate extends longitudinally downward to enhance anti-slip stability; the cohesive soil isolation layer covers the outward-facing cantilever; the fine sand buffer layer is located between the gravel drainage layer and the underground waterproof structure; the drainage trench has grid holes on its side for collecting groundwater in the gravel drainage layer and the fine sand buffer layer and discharging it to the municipal pipe network.

[0007] Furthermore, the water-retaining plate extends downwards along the bottom of the underground structure sidewall to below the gravel drainage layer, with the depth determined according to geological conditions.

[0008] Furthermore, an isolation geotextile is laid between the fine sand buffer layer and the gravel hydrophobic layer to prevent fine sand from entering the pores of the gravel layer.

[0009] Furthermore, the water collection ditch is set along the bottom of the side wall of the underground structure and the groundwater is drawn to the municipal pipeline interface by the slope.

[0010] Furthermore, a double-layer geotextile is provided between the gravel hydrophobic layer, the fine sand buffer layer, and the water collection ditch in the hydrophobic system.

[0011] Furthermore, the fine sand buffer layer is not less than 200mm, which is used to buffer the turbulent flow of the gravel drainage layer into the underground structure at high flow rates; the gravel drainage layer is not less than 300mm, which is used to guide groundwater. The two layers work together to achieve groundwater drainage and reduce the risk of buoyancy of the underground structure.

[0012] Correspondingly, this utility model also provides a construction method for an underground drainage sidewall structure, including the following steps:

[0013] a. Excavate to an elevation of at least 500mm below the surface of the underground structure's bottom slab, and lay a layer of crushed stone and a layer of fine sand as a buffer, wherein the thickness of the fine sand buffer layer is not less than 200mm and the thickness of the crushed stone and the layer of fine sand is not less than 300mm.

[0014] b. The trench construction of the drainage sidewall includes a sidewall structure with inward and outward cantilevered ears and downward extending baffles. At the same time, a water collection ditch is set at the drainage outlet. The side of the water collection ditch has vertical grid holes and is connected to the municipal pipe network.

[0015] c. After the basement roof structure is completed, a permeability coefficient ≤1×10⁻⁶ should be used. -7 A cohesive soil isolation layer with a density of cm / s is applied over the outward-facing protrusions, compacted in layers, and backfilled to the outdoor ground level.

[0016] Furthermore, in step b, the inward and outward cantilevered ears are integrally cast with the underground structure sidewall, and the water-retaining plate extends downward along the bottom of the sidewall to below the gravel drainage layer.

[0017] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0018] This utility model discloses an underground drainage sidewall structure, which is arranged in the enclosure structure of an underground structure. It is mainly used for anti-buoyancy in underground structures. By setting inward and outward cantilevered ears, water-retaining plates, and cohesive soil isolation, the water pressure and flow velocity entering the underground structure are significantly reduced. Then, the drainage layer and buffer layer are used to guide the groundwater to the municipal pipe network through a collection trench, thereby achieving a pressure relief effect. Through the synergistic effect of the cohesive soil isolation layer, the inner and outer cantilevered ears, and the water-retaining plates, the impact of groundwater flow velocity and water pressure on the waterproof layer is effectively reduced. Furthermore, this drainage sidewall structure eliminates the need for the original structural waterproofing slab used for underground structure waterproofing, thus significantly reducing the need for anchor bolts or anti-uplift piles used for structural anti-buoyancy.

[0019] This structure replaces traditional anti-buoyancy measures, and the active drainage design reduces reliance on expensive pull-out piles. A drainage layer replaces the monolithic waterproofing slab, simplifying the construction process. Integrated casting and layered laying processes improve construction efficiency, while the rational use of materials such as cohesive soil and gravel reduces costs. Attached Figure Description

[0020] Figure 1 This is a cross-sectional schematic diagram of an embodiment of the underground drainage sidewall structure of this utility model;

[0021] Figure 2 This is a schematic diagram of the drainage layer of an underground drainage sidewall structure connected to a trench according to an embodiment of the present invention;

[0022] Figure 3 This is a schematic diagram of the trench opening in an embodiment of the underground drainage sidewall structure of this utility model;

[0023] Figure 4 This is a schematic diagram of the overall plan layout of the underground drainage sidewall structure according to an embodiment of the present invention.

[0024] The numbers in the diagram are as follows: 1. Underground structure sidewall; 2. Cohesive soil isolation layer; 3. Underground structure roof slab; 4. Indoor floor layer; 5. Outward cantilever; 6. Inward cantilever; 7. Downward extending water-retaining plate; 8. Underground waterproof structure; 9. Fine sand buffer layer; 10. Crushed stone drainage layer; 11. Isolation geotextile; 12. Double-layer isolation geotextile; 13. Water collection ditch. Detailed Implementation

[0025] The underground drainage sidewall structure proposed in this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. The advantages and features of this utility model 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 this utility model.

[0026] Please see Figure 1 In this embodiment, the underground drainage sidewall structure is arranged in the enclosure structure of the underground structure and is mainly used for the anti-buoyancy of the underground structure. The structure includes an underground structure sidewall 1, on which inward cantilever lugs 6 and outward cantilever lugs 5 are provided. The inward cantilever lugs 6 extend into the underground structure and can effectively reduce the water pressure and flow velocity of groundwater entering the underground structure; the outward cantilever lugs 5 extend outward into the underground structure and, in addition to reducing the flow velocity and water pressure of groundwater, also provide a certain amount of ballast to the underground structure to resist buoyancy.

[0027] At the bottom of the underground structural sidewall 1, a downward-extending water-retaining plate 7 is installed. This water-retaining plate 7 extends longitudinally downward to below the gravel drainage layer 10, and its depth is determined according to geological conditions. It can enhance the anti-slip stability of the underground sidewall and also slow down the flow velocity and water pressure of groundwater to a certain extent. Above the outward-facing lug 5, a cohesive soil isolation layer 2 is provided. This cohesive soil isolation layer has a permeability coefficient ≤1×10⁻⁶. -7 The cohesive soil with a flow rate of cm / s serves as a waterproof layer above the outward-facing eaves of the basement, further slowing down the groundwater flow rate and pressure. It also acts as a buoyancy barrier and prevents high-flow-rate groundwater from eroding and damaging the sidewall waterproofing layer.

[0028] Between the underground waterproof structure 8 and the gravel drainage layer 10, a fine sand buffer layer 9 with a thickness of not less than 200 mm is provided. This buffer layer is primarily used to buffer turbulent flow into the underground structure from the gravel drainage layer 10 at high flow velocities. The gravel drainage layer 10, with a thickness of not less than 300 mm, is mainly used to guide groundwater. The combination of these two layers effectively guides groundwater, reducing the risk of buoyancy in the underground structure. To prevent fine sand from entering the pores of the gravel layer, an isolation geotextile 11 is laid between the fine sand buffer layer 9 and the gravel drainage layer 10.

[0029] Please see Figures 2-3 A water collection ditch 13 is installed at the bottom of the underground structure sidewall 1. This ditch 13 is arranged along the bottom of the sidewall and, with a certain slope, collects groundwater to the municipal pipe network interface. In the drainage system, a double-layer geotextile 12 is installed between the gravel drainage layer 10, the fine sand buffer layer 9, and the water collection ditch 13. Vertical grid openings are formed on the side of the water collection ditch 13. These grid openings are used to collect the groundwater drained from the gravel drainage layer 10 and the fine sand buffer layer 9, which is then collected and discharged through the connected municipal pipe network, thereby achieving effective groundwater discharge and pressure relief.

[0030] Please see Figure 4 The entire underground drainage sidewall structure can adopt this drainage sidewall as a whole. After the groundwater under the underground structure is sloped, it can flow into the water collection ditch 13 at the outlet. It is collected through the grid holes of the water collection ditch and discharged into the municipal pipe network, realizing the drainage and discharge of groundwater around the entire underground structure.

[0031] During construction, the site is first excavated to a height of at least 500mm below the surface of the underground structure's bottom slab. Then, a gravel drainage layer 10 and a fine sand buffer layer 9 are laid in layers, with the fine sand buffer layer 9 having a thickness of not less than 200mm and the gravel drainage layer 10 having a thickness of not less than 300mm.

[0032] Next, the drainage sidewall is constructed by excavating trenches. A sidewall structure with inward-facing lugs 6, outward-facing lugs 5, and a downward-extending baffle 7 is poured. The inward-facing lugs 6 and outward-facing lugs 5 are integrally cast with the underground structure sidewall 1. The baffle 7 extends downwards along the bottom of the sidewall to below the gravel drainage layer 10. Simultaneously, a water collection ditch 13 is installed at the drainage outlet. The side of the water collection ditch 13 has vertical grid holes and is connected to the municipal pipe network.

[0033] After the basement roof slab structure is completed, a permeability coefficient ≤1×10⁻⁶ will be used. -7 A cohesive soil isolation layer 2 with a density of cm / s is placed over the outward-facing ears 5, compacted in layers, and backfilled to the outdoor ground level.

[0034] Through the above structural design and construction methods, the underground drainage sidewall structure of this utility model can effectively solve the problem of buoyancy resistance of underground structures, eliminate the original structural waterproofing board used for waterproofing underground structures, significantly reduce the anchor rods or anti-uplift piles used for structural buoyancy resistance, and significantly save investment in underground structures, thus having good economic efficiency and practicality.

[0035] 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. An underground drainage sidewall structure, characterized in that, include: The underground structure includes an inward-pointing ear (6), an outward-pointing ear (5), a downward-extending water-retaining plate (7), a cohesive soil isolation layer (2), a fine sand buffer layer (9), a gravel drainage layer (10), an isolation geotextile (11), and a water collection ditch (13). The inward-pointing ear (6) extends into the underground structure to reduce groundwater pressure and flow velocity, while the outward-pointing ear (5) extends outward from the underground structure and also serves as a weight-bearing and anti-buoyancy function. The water-retaining plate (7) extends longitudinally downward to enhance anti-slip stability. The cohesive soil isolation layer (2) covers the outward-pointing ear (5). The fine sand buffer layer (9) is located between the gravel drainage layer (10) and the underground waterproof structure (8). The water collection ditch (13) has grid holes on its side for collecting groundwater from the gravel drainage layer (10) and the fine sand buffer layer (9) and discharging it to the municipal pipe network.

2. The underground drainage sidewall structure according to claim 1, characterized in that, The water-retaining plate (7) extends downward along the bottom of the underground structure sidewall (1) to below the gravel drainage layer (10), with the depth determined according to geological conditions.

3. The underground drainage sidewall structure according to claim 1, characterized in that, An isolation geotextile (11) is laid between the fine sand buffer layer (9) and the gravel hydrophobic layer (10) to prevent fine sand from entering the pores of the gravel layer.

4. The underground drainage sidewall structure according to claim 1, characterized in that, The water collection ditch (13) is set along the bottom of the underground structure sidewall (1) and the groundwater flows to the municipal pipeline interface through the slope.

5. The underground drainage sidewall structure according to claim 1, characterized in that, A double-layer geotextile (12) is installed between the gravel drainage layer (10), the fine sand buffer layer (9), and the water collection ditch (13) of the drainage system.

6. The underground drainage sidewall structure according to claim 1, characterized in that, The fine sand buffer layer (9) is not less than 200mm and is used to buffer the turbulent flow of the gravel drainage layer into the underground structure at high flow rates; the gravel drainage layer (10) is not less than 300mm and is used to drain groundwater. The two layers work together to drain groundwater and reduce the risk of buoyancy in the underground structure.

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