CN215948238U

CN215948238U - Be applied to drainage device in excavation supporting

Info

Publication number: CN215948238U
Application number: CN202122095056.8U
Authority: CN
Inventors: 潘有旺; 魏伟; 邸永健; 雒奇奇; 吴爱宏
Original assignee: Gansu Jiantou Geotechnical Technology Co ltd
Current assignee: Gansu Jiantou Geotechnical Technology Co ltd
Priority date: 2021-09-01
Filing date: 2021-09-01
Publication date: 2022-03-04
Anticipated expiration: 2031-09-01

Abstract

The utility model belongs to the technical field of foundation pit support, and discloses a drainage device applied to the junction of a pebble layer and a red sandstone layer, which is used for solving the technical problems existing in foundation pit support precipitation in the prior art, and comprises a gravel layer arranged at the junction of the pebble layer and the red sandstone layer, wherein the bottom of the gravel layer is provided with a water collecting funnel, the bottom of the water collecting funnel is connected with a longitudinal drain pipe, the bottom of the longitudinal drain pipe is connected with a wall-hanging drain pipe, the wall-hanging drain pipe is connected with a water collecting well, the water collecting funnel and the longitudinal drain pipe are arranged close to one side of the red sandstone layer, the side part of the red sandstone layer is provided with a water isolating device, and an external spray anchor support is ensured to be constructed in a dry operation environment by adopting water isolating measures on the junction of the two layers and the surface of sandstone, the water is collected by the water collecting funnel, is discharged by the vertical water discharging pipe and the wall-mounted water discharging pipe, and provides the internal flowing water capability.

Description

Be applied to drainage device in excavation supporting

Technical Field

The utility model relates to the technical field of foundation pit support, in particular to a drainage device applied to the junction of a pebble bed and a red sandstone bed.

Background

In recent years, along with the development of national economy, basements in main urban areas of cities show a deeper and deeper trend, most basements of newly built residences in Lanzhou areas are designed with 2-3 floors, and foundation pit support is particularly important for ensuring the safety of surrounding buildings.

For the deep foundation pit, the support form is various, and the economy, safety and applicability are considered, the deep foundation pit support in Lanzhou area is mainly based on pile anchor support, and the comprehensive support precipitation mode of 'pile anchor + pipe well + catchment open drainage' or 'secant pile water stop + anchor rope + pipe well precipitation' is mainly combined with the underground water level condition.

With the increase of super high-rise buildings and the successful construction of No. 1 line of Lanzhou subway in recent years, in foundation construction, how to deal with the problem of red sandstone support precipitation in the Lanzhou area becomes the difficult point of deep foundation pit support construction in the Lanzhou area. At present, the support of the red sandstone layer is mostly solved by adopting a secant pile support, but the construction speed is slower, the requirement on the construction precision is higher, and the construction cost is higher. The geological structure of Lanzhou city of Gansu province is very complicated, the deep foundation pit of Lanzhou city of Gansu province is in the pebble layer and the sandstone layer because of the water level, part of the basic elevations of the raft, the sump, the elevator shaft and the like of the main building are lower than the elevation of the pebble-sandstone junction layer, the sand content in the strong-differentiation sandy mudstone of the field part is larger, and the area with larger local sand content is fully-differentiation sandstone, a thin-layer structure and argillaceous cementation. Fully-differentiated sandstone with the thickness of about 2-3.5 m is uniformly distributed on the top of the argillaceous sandstone. The permeable coefficient of the pebble layer is large, the permeable coefficient of the fully-differentiated sandstone layer is low, the problem of precipitation under the condition that pebbles and the sandstone layer exist at the same time is often encountered in the excavation and supporting process of a building foundation pit, the permeable coefficient of the pebble layer is large, the permeable coefficient of the sandstone layer is low, the water seepage in the common pipe well precipitation can not be reduced, the water seepage is generally caused at the joint surface of the pebble layer and the sandstone layer, the supporting difficulty of the foundation pit is large, if the sandstone layer is not supported timely enough and the effect is not good enough, the accidents of sand gushing and collapse of the foundation pit can be easily caused, and the technical problem can not be solved in the prior art.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problems in foundation pit supporting precipitation in the prior art, and provides a drainage device which is high in construction speed, convenient and economical to construct and applied to the junction of a pebble bed and a red sandstone bed.

In order to achieve the purpose, the utility model adopts the following technical scheme:

the utility model provides a be applied to drainage device in excavation supporting, is including setting up the metalling in cobble bed and red sandstone layer juncture, the bottom of metalling is equipped with the funnel that catchments, and the bottom of funnel that catchments is connected with the longitudinal drain pipe, and the bottom of longitudinal drain pipe has the sump pit through horizontal drain pipe connection, the one side setting on red sandstone layer that funnel and longitudinal drain pipe of catchmenting are close to, and the lateral part on red sandstone layer is equipped with the water proof device.

Further, the water proof device is including laying the water proof layer on the red sand rock stratum surface course, and the skin of water proof layer is equipped with grass curtain layer, and the outside of grass curtain layer is equipped with the reinforcing bar net piece, and the outside of reinforcing bar net piece is equipped with concrete layer.

Furthermore, a steel bar framework is arranged between the grass curtain layer and the steel bar net piece, and the grass curtain layer is fixed on the inner side of the steel bar framework through binding wires.

Furthermore, a filter screen is laid between the crushed stone layer and the water collecting funnel.

Furthermore, the water collecting funnel is a special-shaped funnel, and one side wall of the special-shaped funnel is parallel to the vertical surface and is close to the waterproof layer.

Further, the longitudinal drain pipe is close to the water barrier.

Furthermore, the longitudinal drain pipe is connected with the wall-hanging drain pipe through an elbow.

Furthermore, the transverse drain pipe is a wall-mounted drain pipe arranged at the bottom of the foundation pit.

Further, the water-proof layer is plastic cloth.

Compared with the prior art, the utility model has the following beneficial effects:

the drainage device applied to the foundation pit support is implemented when earth is excavated to the joint of the pebble bed and the red sandstone bed, and the construction of the external spray anchor support in a dry working environment is ensured by taking water-resisting measures on the joint of the two layers and the sandstone surface. And the spray anchor support under the condition that underground water exists on the surface of the sandstone layer is realized by a mode of artificially additionally arranging a spray anchor construction base layer on the outer side of the waterproof layer. The utility model can effectively ensure the stability of soil quality between the piles supported by the foundation pit pile anchor, so that water between the piles flows into the gravel layer, is collected by the water collecting funnel and is discharged by the longitudinal water discharge pipe and the wall-mounted water discharge pipe, and the internal flowing water capacity is provided.

The utility model can ensure the stability among foundation pit piles, effectively control the water stability of foundation pit engineering, prolong the durability of foundation pit support and ensure the safety of a foundation pit support structure and adjacent buildings.

The utility model forms the water-resisting device by the water-resisting layer, the straw curtain and the like, and ensures that the external spray anchor support is constructed in a dry operation environment. According to the utility model, the filter screen is laid between the crushed stone layer and the water collecting funnel, so that the drained water flows through the water collecting funnel after being filtered. In addition, the drainage device is arranged along one side of the sandstone layer, so the water collecting funnel adopts a special-shaped water collecting funnel.

According to the utility model, flowing water between piles in the pebble layer is filtered through the gravel layer with the height of 100mm and the width of 300mm, small flowing water openings are reserved at the gravel positions every 20mm, and then the gravel layers are filtered through the filter screen, so that the water flows into the water collection funnel, the longitudinal water discharge pipe is connected with the wall-hanging water discharge pipe through the elbow, the water in the longitudinal water discharge pipe is led into the water collection well through the wall-hanging water discharge pipe and is pumped away by the water pump, the structure is simple, and the construction is convenient and economic.

Drawings

FIG. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a top sectional view of the present invention.

Fig. 3 is a side cross-sectional view of the present invention.

Fig. 4 is a partially enlarged schematic view of fig. 1.

The reference numerals have the following meanings: 1. filling piles; 2. a pebble layer; 3. a crushed stone layer; 4. filtering with a screen; 5. a water collection funnel; 6. a longitudinal drain pipe; 7. a red sandstone layer; 8. a wall-hanging drain pipe; 9. bending the pipe; 10. a water barrier layer; 11. a straw curtain layer; 12. a steel reinforcement cage; 13. reinforcing mesh sheets; 14. a concrete layer; 15. a water collecting well.

Detailed Description

The utility model is further described with reference to the following figures and detailed description.

As shown in fig. 1-4, a drainage device applied to foundation pit support comprises a gravel layer 3 arranged at the junction of a pebble layer 2 and a red sandstone layer 7, a water collecting funnel 5 arranged at the bottom of the gravel layer 3, and a filter screen 4 laid between the gravel layer 3 and the water collecting funnel 5. The bottom of funnel 5 that catchments is connected with vertical drain pipe 6, and vertical drain pipe 6's bottom is connected with wall built-up drain pipe 8, is connected through elbow 9 between vertical drain pipe 6 and the wall built-up drain pipe 8. The wall built-up drain pipe 8 is connected with the sump pit 15, and the funnel 5 that catchments and the one side setting of the red sandstone layer 7 that longitudinal drain pipe 6 is close to, and the lateral part of red sandstone layer 7 and the juncture of cobble layer 2 and red sandstone layer 7 are equipped with water stop.

The water-resisting device comprises a water-resisting layer 10 paved on the red sandstone layer 7 surface layer, and the water-resisting layer 10 is plastic cloth. The outer layer of water barrier 10 is equipped with grass curtain layer 11, and the outside of grass curtain layer 11 is equipped with framework of steel reinforcement 12, and grass curtain layer 11 is fixed at framework of steel reinforcement 12 inboard through pricking the silk. The outside of steel reinforcement framework 12 is equipped with reinforcing bar net piece 13, and the outside of reinforcing bar net piece 13 is equipped with concrete layer 14. The water collecting funnel 5 is a special-shaped funnel, one side wall of the special-shaped funnel is parallel to the vertical surface and is close to the waterproof layer 10, and the longitudinal drain pipe 6 is close to the waterproof layer 10.

During operation, firstly, earthwork between cast-in-place piles 1 is excavated according to geological exploration, the junction of a pebble layer 2 and a red sandstone layer 7 is found, a space for installing a drainage device is chiseled, a gravel layer 3 and a filter screen which are 5cm thick around the drainage device are laid firstly, small running water openings are reserved on the gravel layer 3 every 20mm during laying, then a gravel layer (10cm x 30cm) and a filter screen which are arranged on the upper portion of a water collecting funnel 5 are laid, the water collecting funnel 5 is designed in a special shape, the side wall of the water collecting funnel 5 is ensured to be tightly attached to an external water-resisting device with a longitudinal drainage pipe 6(DN50pvc), and the space between piles is ensured to be compact. And finally, the water pipe is connected to the bottom of the foundation pit, is connected to a wall-mounted drain pipe 8(DN50pvc) by adopting a 90-degree elbow, and flows into the water collecting well 15 and then is pumped away by a water pump.

The water-resisting device is laid on the outer side of the drainage device, the plastic cloth water-resisting layer 10, the grass curtain layer 11, the steel bar framework 12, the steel bar net piece 13 and the gunite are laid respectively, the thickness of the selected grass curtain 11 is not smaller than 40mm, the grass curtain 11 is fixed on the inner side of the steel bar framework 12 through the binding wires, and the plastic cloth 10 is pressed and stuck on the sandstone surface layer 7 through the steel bar framework 12 and the grass curtain 11 together. Because the plastic cloth and the straw curtain are inflammable, the installation is carried out after the temperature of the to-be-welded seam is reduced to normal temperature.

Claims

1. The utility model provides a be applied to drainage device in excavation supporting, characterized by: including setting up rubble layer (3) at pebble layer (2) and red sandstone layer (7) juncture, the bottom of rubble layer (3) is equipped with water collection funnel (5), and the bottom of water collection funnel (5) is connected with longitudinal drain pipe (6), and the bottom of longitudinal drain pipe (6) is connected with sump pit (15) through horizontal drain pipe, one side setting of red sandstone layer (7) that water collection funnel (5) and longitudinal drain pipe (6) are close to, and the lateral part of red sandstone layer (7) and the juncture of pebble layer (2) and red sandstone layer (7) are equipped with the water proof device.

2. The drainage device applied to foundation pit support according to claim 1, wherein the water-resisting device comprises a water-resisting layer (10) paved on a surface layer of the red sand rock layer (7), a grass curtain layer (11) is arranged on the outer layer of the water-resisting layer (10), a steel bar mesh (13) is arranged on the outer side of the grass curtain layer (11), and a concrete layer (14) is arranged on the outer side of the steel bar mesh (13).

3. The drainage device applied to foundation pit support according to claim 2, wherein a steel bar framework (12) is arranged between the grass curtain layer (11) and the steel mesh (13), and the grass curtain layer (11) is fixed on the inner side of the steel bar framework (12) through binding wires.

4. A water drainage device applied to foundation pit support according to claim 3, wherein a filter screen (4) is laid between the gravel layer (3) and the water collection funnel (5).

5. A drainage device for use in foundation pit support according to claim 4, wherein the water collection funnel (5) is a shaped funnel having a side wall parallel to the vertical plane and adjacent to the water barrier (10).

6. A drainage arrangement for use in foundation pit support according to claim 5, wherein the longitudinal drainage pipe (6) is adjacent the water barrier (10).

7. A drainage arrangement for use in foundation pit support according to claim 1 or 6, wherein the lateral drainage pipe is a wall built-up drainage pipe (8) arranged at the bottom of the foundation pit.

8. A drainage device for use in foundation pit support according to claim 7, wherein the longitudinal drain pipe (6) is connected with the wall built-up drain pipe (8) by an elbow (9).

9. A drainage device for use in foundation pit support according to claim 6, wherein the water barrier (10) is a plastic cloth.