CN105544622A - Floating resisting device, and seepage insulation device and drainage path checking device thereof for underground building - Google Patents

Abstract

The invention discloses an anti-floating device for an underground structure: through the combined use of a seepage isolation device, a drainage device and a drainage channel inspection device, the buoyancy of the underground water on the underground structure can be effectively reduced, thereby reliably preventing the underground structure from floating Purpose. Specifically: build a horizontal seepage barrier layer (3) on the top of the foundation pit backfill area between the underground building exterior wall (6) and the foundation pit boundary (4); Layer (1): At least two parallel porous water collection pipes or water collectors (17, 18) not directly connected to each other are laid in the permeable soil layer (1) and each connected to at least one water outlet (2). After the above measures are taken, the anti-floating water level of the underground structure is determined by the elevations of at least two water outlets (2) having the same elevation. The invention also discloses a groundwater seepage isolation device for an underground building and a groundwater drainage path inspection device.

Description

An anti-floating device for an underground building, its seepage isolation device, and a drainage channel inspection device

technical field

The invention relates to an anti-floating device of an underground building, and also relates to a groundwater seepage isolation device of an underground building and a groundwater drainage channel inspection device.

Background technique

In order to avoid the buoyancy of groundwater causing underground buildings to float, various anti-floating measures have been adopted in the prior art: a. Set uplift piles, relying on the pullout force of the uplift piles to offset the buoyancy of underground buildings; b. Set pressure Heavy objects rely on the gravity of the ballast to counteract the buoyancy of underground structures; c. Set up groundwater drainage devices to reduce the groundwater level by discharging groundwater, thereby reducing the buoyancy of underground structures. These three measures have their own deficiencies: the engineering costs of type a and type b measures are relatively high, and the economy is poor; the construction period of type a measures is long; High; some measures in category c need to drill many holes in the outer wall and floor to ensure the complete drainage of groundwater, so it has a certain impact on the use of underground buildings; in the long run, the drainage channels of category c have the risk of siltation and blockage.

For the geological environment where the soil layer below the base plate of the underground building (5) and around the boundary of the foundation pit of the underground building (4) are all impermeable soil layers (8), the source of groundwater is mainly the stagnant water in the surface soil layer in the backfill area of the foundation pit of the underground building seepage downward, there is no diving, pressurized water and other groundwater in the scope of the underground building foundation pit. For this kind of geological environment, there are technical measures that suggest the use of d-type measures: the backfill soil in the backfill area of the foundation pit is made of cohesive soil or lime soil, which is rolled or compacted in layers, in an attempt to eliminate the buoyancy of the underground structure. . However, since the "rolling or tamping" in the construction process is greatly affected by human factors, it is difficult to ensure stable and reliable construction quality, so this measure is not reassuring.

In water conservancy projects and port projects, various composite geomembranes have been widely used as vertical anti-seepage materials, and the seepage isolation effect is very good. The present invention introduces this type of material into the field of underground water seepage isolation for underground buildings; in the patent document [application No. 201420655634.6] (hereinafter referred to as document 1) discloses a drainage device for underground water in underground buildings, which is introduced into the anti-floating field of underground buildings for use in the present invention.

Contents of the invention

Aiming at the geological environment where the soil layers below the base plate (5) of the underground building and around the boundary of the foundation pit of the underground building (4) are all impermeable soil layers (8), the present invention provides a simple and reliable anti-floating method for underground buildings: The combined application of the seepage isolation device and the drainage device can effectively reduce the buoyancy of the groundwater suffered by the underground structure, thereby achieving the purpose of reliably preventing the underground structure from floating.

Technical scheme of the present invention: build a water-permeable soil layer (1) in the lower part of the foundation pit backfill area between the underground building exterior wall (6) and the foundation pit boundary (4) of the underground building and connect at least two water outlets with the same elevation ( 2), the permeable soil layer (1) fills the entire foundation pit backfill area along the horizontal direction; build a horizontal seepage barrier layer (3) on the top of the foundation pit backfill area, and the seepage barrier layer (3) covers the entire foundation pit backfill Area, see Fig. 1, Fig. 2; After taking above-mentioned measures, the anti-floating waterproof level of described underground structure is determined by the elevation of described at least two water outlets (2).

The seepage barrier layer (3) is selected according to one of the following devices: a. The seepage barrier layer (3) adopts a flexible, continuous seepage barrier material composed of a composite geomembrane; b. the seepage barrier layer (3) The impermeable material mixed with soil material is adopted, and the impermeable material mixed with soil material at least includes cohesive soil, lime soil or cement soil, and is layered and compacted or compacted; c. Permeable materials and flexible, continuous barrier materials composed of composite geomembranes. The seepage barrier layer (3) forms a slope, and the elevation of the end (9) close to the underground building is higher than the elevation of the end (10) away from the underground building.

When the seepage barrier layer (3) adopts a flexible and continuous seepage barrier material composed of a composite geomembrane, the flexible seepage barrier layer (3) is connected to the exterior wall (6) of the underground building or the roof (7) of the underground building All are tightly sealed, and the flexible seepage barrier layer (3) extends beyond the boundary of the foundation pit of the underground building (4) and is tightly sealed with the impermeable soil layer (8); when an underground pipeline passes through the flexible seepage barrier layer (3 ), the flexible seepage barrier layer (3) is tightly sealed with the outer surface of the underground pipeline. As a further deepening of the connection scheme of the flexible seepage barrier layer (3), one of the following two ways is adopted for the connection of the flexible seepage barrier layer (3) near the underground building end (9) to the underground building: a. Two protrusions (15) are arranged on the outer wall of the building (6), and one end (9) of the flexible seepage barrier layer (3) close to the underground building rises along the outer wall of the underground building (6) to the bottom of the upper bar of the outer wall protrusion (15). , then build a brick wall or pour concrete (16) on its outside to compress and seal, see Fig. 3; Tighten and seal with a pressing weight (14), see Figure 4. The connection of the flexible seepage barrier layer (3) away from the end (10) of the underground building and the impermeable soil layer (8) other than the foundation pit of the underground building adopts the following method: the flexible seepage barrier layer (3) is far away from the underground building One end (10) of the object is inserted into the impermeable soil layer (8) outside the foundation pit of the underground building and is compacted and sealed.

The permeable soil layer (1) and water outlet (2) are selected with reference to the content of the patent document [Document 1]: the permeable soil layer (1) at least includes fine sand, medium sand, coarse sand, gravel, breccia, Round gravel, crushed stone or pebble; the water outlet (2) passes through the outer wall (6) of the underground building and leads to the lower ground, pit or pipe trench in the underground building.

In order to ensure that the groundwater drainage passage between the permeable soil layer (1) and the water outlet (2) is always unobstructed, a groundwater drainage passage inspection device is provided: at least two parallel pipes are laid in the permeable soil layer (1). Porous water collection pipes or water collectors (17,18); said two water collection pipes or water collectors (17,18) are not directly connected to each other, and the two water collection pipes or water collectors (17,18) The flow of water can only be exchanged through the pores of the permeable soil layer (1) between two water collection pipes or water collectors (17, 18); each water collection pipe or water collector (17, 18) Connect at least one water outlet (2), see Figure 5. Fill water into one of the water outlets (2) and observe whether the other water outlet (2) is drained, so as to check whether the groundwater drainage passage between the permeable soil layer (1) and the water outlet (2) is unobstructed at any time. In order to prevent mud and sand from accumulating in the inlet holes of the water collection pipes or water collectors (17, 18), each water collection pipe or water collectors (17, 18) are coated with at least one layer of filter cloth for filtering mud and sand or filter membrane.

The beneficial effect that the present invention has:

Compared with using d-type measures alone, the present invention ensures that underground buildings are safe and reliable against floating by adopting the comprehensive measures of permeable soil layer (1), water outlet (2) and seepage barrier layer (3): seepage barrier layer (3 ) can ensure to reduce or even prevent surface seepage from seeping into the underground building foundation pit; by observing the water output of the water outlet (2), defects can be found in time and remedial measures can be taken to ensure the quality of the project; even if any accident causes water seepage to penetrate into the underground building foundation pit , the permeable soil layer (1) and the water outlet (2) can also discharge the infiltrated groundwater in time, preventing the groundwater level in the foundation pit of the underground building from rising above the water level of the anti-floating structure, and ensuring the safety of the underground building.

Compared with measures of type a and type b, the anti-floating device of the present invention can reduce uplift piles or ballasts, and the engineering cost is lower. Compared with using the measures of category c alone, the present invention can basically prevent surface seepage water from seeping into the foundation pit of underground buildings by setting the seepage barrier layer (3) and checking its sealing performance, and only needs a small amount of pumping and drainage of groundwater during use, and the maintenance cost is relatively low ; In extreme cases, the seepage barrier layer (3) can completely prevent surface seepage from penetrating into the foundation pit of the underground building, basically does not need to pump and drain groundwater, and the maintenance cost is extremely low; due to the small number of required water outlets (2), only (6) A small number of holes through the wall are arranged, and the use of underground buildings is basically not affected.

Compared with rigid impermeable materials or earth-material mixed impermeable materials, the composite geomembrane seepage isolation device of the present invention has better seepage isolation effect. This is because: rigid impermeable materials are difficult to join together, even if the joints are embedded with flexible water-stop materials, it is difficult to ensure that all joints are tight, so it is not recommended to use; the material selection and construction process of soil-mixed impermeable materials are affected by human factors It is difficult to ensure stable and reliable construction quality; composite geomembrane is widely used in water conservancy projects and port projects as a vertical anti-seepage material. The seepage effect is equally effective.

The groundwater drainage channel inspection device of the present invention can check whether the groundwater drainage channel between the permeable soil layer (1) and the water outlet (2) is unobstructed at any time, so as to prevent potential safety hazards caused by silting and blockage.

Description of drawings

Figure 1 is a cross-sectional view of the backfill area of the underground building foundation pit where the roof elevation of the underground building is higher than the ground elevation

Figure 2 is a cross-sectional view of the backfill area of the underground building foundation pit where the roof elevation of the underground building is lower than the ground elevation

Figure 3 is a detailed diagram of the connection between the flexible seepage barrier layer and the exterior wall of the underground building

Figure 4 is a detailed diagram of the connection between the flexible seepage barrier and the roof of the underground building

Figure 5 is a schematic plan view of the positional relationship between the parallel water collection pipe or the water collector and the water outlet

In the figure: 1--permeable soil layer; 2--water outlet; 3--seepage barrier layer; 4--underground building foundation pit boundary; 5--underground building floor; 6--underground building exterior wall; 7-- Roof of underground building; 8--impermeable soil layer outside foundation pit of underground building; 9-end of seepage barrier layer close to underground building; 10-end of seepage barrier layer far away from underground building; 11-backfill soil at the lower part of foundation pit ; 12-backfill on the upper part of the foundation pit; 13-surface backfill; 14-compact heavy objects; 15-underground building external wall protrusion; 16-outside brick wall or concrete block; water vessel

detailed description

Example 1

The second-floor basement of a building is buried at a depth of 10m, and there are no above-ground buildings in some parts. There is a 1m-thick covering soil above the basement roof, and the soil layer around the foundation pit of the underground building is all clay. In order to prevent the basement from floating, the anti-floating device of this patent invention and anti-floating piles are compared: according to the conventional method, the outdoor ground elevation is used as the anti-floating water level of the basement, and anti-floating piles must be installed; the anti-floating piles of the invention are adopted Floating device, with the absolute altitude of water outlet (2) as basement anti-floating establishment water level, local basement just can not float. After comparison, it is decided to adopt the anti-floating device of the present patent invention. The specific implementation method is: reserve the water outlet (2) wall-piercing conduit at the bottom 2.0m of the underground building outer wall (6); Construction in the following order: Backfill the lower soil layer (11) with the earth excavated from the site to the elevation close to the water outlet (2) conduit---backfill the middle permeable soil layer (1) with medium-coarse sand and distribute to all foundation pits for backfilling During this period, a pair of parallel porous water collection pipes (17, 18) surrounding the underground building are placed in the middle of the permeable soil layer (1) and are respectively connected to the conduits leading to the water outlet (2) --- excavated from the site. Backfill the upper soil layer (12) to the elevation of the seepage barrier layer (3)---during the backfilling process, each soil layer is compacted in layers---lay the flexible seepage barrier layer (3) to cover the entire backfill area of the foundation pit and extend to the ground The impermeable soil layer (8) outside the building foundation pit boundary (4) (see Figure 2)---one end (10) of the flexible seepage barrier layer is inserted into the impermeable soil layer (8) outside the foundation pit of the underground building and compacted Dense sealing --- the other end of the flexible seepage barrier layer (9) is closely attached to the roof of the underground building (7) and sealed with a compaction weight (14) (see Figure 4) --- backfill the surface soil layer (13) and Complete various pipeline installations.

During the use of the underground building, it is observed that water flows out of the water outlet (2), but the amount of water is very small, forming dripping water. No obvious deformation was found in the settlement observation of the building, structural beams, columns and other components were working normally, and no cracks were found, which proves that it is safe and reliable to use the elevation of the water outlet (2) as the water level of the anti-floating construction of the basement.

Example 2

The second-floor basement of a building is buried at a depth of 10m, and some above-ground buildings have only one floor. The roof of the basement is higher than the outdoor ground, and the soil around the foundation pit of the underground building is clay. The device of this patent invention is used to resist floating. Due to the narrow site and the width of the foundation pit of the underground building is less than 1m, it is difficult to ensure the construction quality of the backfill soil. Therefore, it is decided to use a composite geomembrane as the seepage barrier layer (3) to ensure the seepage isolation effect. The specific implementation method is: in the outer wall of the underground building (6 ) to reserve water outlets (2) through-wall conduits and outer wall protrusions (15); foundation pit backfilling shall be constructed in the following order from bottom to top: backfill the lower soil layer (11) with the earth excavated from the site until it is close to the water outlet (2) The elevation of the conduit --- backfill the middle permeable soil layer (1) with medium coarse sand and distribute it to the backfill area of the entire foundation pit, during which a pair of parallel holes surrounding the underground building are placed in the middle of the permeable soil layer (1) The water collection pipes ((17, 18) are respectively connected to the water outlet (2) conduit --- backfill the upper soil layer (12) to the elevation of the seepage barrier layer (3) with the earth excavated from the site --- lay the seepage barrier Layer (3) covers the entire foundation pit backfill area and extends to the impermeable soil layer (8) beyond the boundary (4) of the underground building foundation pit (see Figure 1)---one end (10) of the seepage barrier layer is inserted into the underground building foundation pit The other end of the seepage barrier (9) rises along the exterior wall (6) of the underground building to the bottom of the upper strip of the protrusion (15) of the exterior wall, and then on the outside of the impermeable soil layer (8). The masonry brick wall (16) is compacted and sealed (see Figure 3)---backfill the surface soil layer (13) and complete the installation of various pipelines; all sealing parts of the seepage barrier layer (3) are tested for sealing performance.

During the use of the underground building, it was observed that there was basically no water flowing out of the water outlet (2), and occasionally there was a small amount of dripping water in the heavy rain season, which showed that the composite geomembrane seepage isolation device had a good seepage isolation effect.

Claims (10)

1. A kind of anti-floating device of underground building, underground building comprises underground building outer wall (6), underground building base plate (5), underground building roof (7), underground building outer wall (6) and underground building foundation pit The area between the boundaries (4) is the backfill area of the foundation pit, and the soil layer below the base plate of the underground building (5) and outside the boundary of the foundation pit of the underground building (4) is an impermeable soil layer (8); it is characterized in that: in the foundation pit A horizontal seepage barrier (3) is built on the top of the backfill area, and the seepage barrier (3) covers the entire foundation pit backfill area; a permeable soil layer (1) is constructed in the lower part of the foundation pit backfill area and connected to at least two A water outlet (2), the permeable soil layer (1) fills the entire backfill area of the foundation pit along the horizontal direction. 2. according to the anti-floating device of a kind of underground structure of claim 1, it is characterized in that: described seepage barrier layer (3) is selected by one of following device: a. described seepage barrier layer (3) adopts by composite geotechnical The flexible, continuous seepage barrier material that membrane is made of; b. described seepage barrier layer (3) adopts soil material to mix impermeable material, and soil material mixes water-impermeable material to at least comprise cohesive soil, lime soil or cement soil; The permeable material is layered and compacted or compacted; c. The seepage barrier layer (3) is superimposed with a flexible and continuous seepage barrier material composed of soil mixed impermeable material and composite geomembrane. 3. The anti-floating device of a kind of underground building according to claim 2, characterized in that: the connection between the flexible seepage barrier layer (3) and the outer wall (6) of the underground building or the roof (7) of the underground building is tight Sealing, the flexible seepage barrier layer (3) extends beyond the boundary of the underground building foundation pit (4) and is tightly sealed with the impermeable soil layer (8); when an underground pipeline passes through the flexible seepage barrier layer (3), The flexible seepage barrier layer (3) is tightly sealed with the outer surface of the underground pipeline. 4. The anti-floating device of an underground structure according to claim 1, characterized in that: the permeable soil layer (1) at least includes fine sand, medium sand, gravel sand, breccia, round gravel, gravel, pebbles , blocks or boulders; the at least two water outlets (2) with the same elevation pass through the outer wall (6) of the underground building and lead to the lower ground, pit or pipe trench in the interior of the underground building. 5. The anti-floating device of a kind of underground structure according to claim 1, characterized in that: at least two parallel porous water collection pipes or water collectors (17, 18) are laid in the permeable soil layer (1); The two water collection pipes or water collectors (17, 18) are not directly connected to each other, and the current in the two water collection pipes or water collectors (17, 18) can only pass through two water collection pipes or water collectors ( 17, 18) between the pores of the permeable soil layer (1) to communicate with each other; each water collection pipe or water collector (17, 18) communicates with at least one water outlet (2). 6. The anti-floating device of a kind of underground structure according to claim 5, characterized in that: the outer surface of each water collection pipe or water collector (17, 18) is covered with at least one layer of filter cloth for filtering mud and sand or filter membrane. 7. A groundwater seepage isolation device for an underground building, the underground building comprising an underground building exterior wall (6), an underground building floor (5), an underground building roof (7), an underground building exterior wall (6) and an underground building foundation The area between the pit boundaries (4) is the backfill area of the foundation pit, and the soil layer below the base plate of the underground building (5) and outside the foundation pit boundary (4) of the underground building is an impermeable soil layer (8); it is characterized in that: A horizontal seepage barrier (3) is constructed on the upper part of the pit backfill area, and the seepage barrier (3) covers the entire foundation pit backfill area; the seepage barrier (3) adopts a flexible and continuous barrier made of composite geomembrane seepage material. 8. The groundwater seepage isolation device for an underground building according to claim 7, characterized in that: the flexible seepage isolation layer (3) is connected to the outer wall (6) of the underground building or the roof (7) of the underground building All places are tightly sealed; the flexible seepage barrier layer (3) extends beyond the boundary of the foundation pit of the underground building (4) and is tightly sealed with the impermeable soil layer (8); when an underground pipeline passes through the flexible seepage barrier layer (3 ), the flexible seepage barrier layer (3) is tightly sealed with the outer surface of the underground pipeline. 9. The groundwater seepage isolation device for an underground structure according to claim 7 or 8, characterized in that: the flexible seepage isolation layer (3) is connected to one end (9) of the underground structure and the underground structure using One of the following two ways: a. Two protrusions (15) are set on the exterior wall of the underground building (6), and the flexible seepage barrier layer (3) is close to one end (9) of the underground building along the exterior wall of the underground building (6). Rise to the bottom of the upper strip of the outer wall protrusion (15), and then build a brick wall or pour concrete (16) on the outer side of it to compress and seal; b. The flexible seepage barrier layer (3) is close to the end of the underground building (9) Closely attached to the roof of the underground building (7) and pressed and sealed with a pressing weight (14); The connection of the flexible seepage barrier layer (3) away from the end (10) of the underground building and the impermeable soil layer (8) other than the foundation pit of the underground building adopts the following method: the flexible seepage barrier layer (3) is far away from the underground building One end (10) of the object is inserted into the impermeable soil layer (8) outside the foundation pit of the underground building and is compacted and sealed. 10. A groundwater drainage passage inspection device for an underground structure, characterized in that: lay at least two parallel porous water collection pipes or water collectors (17, 18) in the underground permeable soil layer (1); Water collection pipes or water collectors (17, 18) are not directly connected to each other, and the water flow in two water collection pipes or water collectors (17, 18) can only pass through two water collection pipes or water collectors (17, 18) The pores of the permeable soil layer (1) between them are used for mutual communication; each water collection pipe or water collector (17, 18) communicates with at least one water outlet (2).