Tubular pile gushing drainage system in foundation pit
By sealing the upper end of the pipe pile core with concrete and using a water pipe to drain the gushing water, combined with a sump and drainage system, the problem of gushing water from the pile core in foundation pit engineering was solved, achieving both construction safety and economy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANGHAI CHANGKAI GEOTECHN ENG
- Filing Date
- 2025-04-23
- Publication Date
- 2026-05-01
AI Technical Summary
In foundation pit engineering, the core of the engineering pipe pile is prone to sudden heaving during construction, which can lead to adverse effects such as softening of the foundation pit soil and ground settlement.
The upper opening of the pipe pile core is sealed with a concrete sealing body, and the sudden water flow is discharged through a water pipe. Combined with a temporary sump and an external drainage ditch system, the water is discharged outside the foundation pit using a submersible pump.
It effectively prevents the spread of sudden water in the foundation pit, avoiding adverse effects on subsequent construction, and is simple, economical, and environmentally friendly to construct.
Smart Images
Figure CN224186725U_ABST
Abstract
Description
Pipe pile inrush drainage system Technical Field
[0001] This utility model relates to an auxiliary device for pile foundation construction, and more particularly to a system for draining sudden surges of pipe piles in a foundation pit. Background Technology
[0002] Underground space development involves both permanent and temporary underground structures, specifically in the two key areas of foundation engineering and excavation pit engineering. Among these, the construction of engineering piles in foundation engineering presents various challenges. While some solutions have been developed as projects progress, unforeseen problems can arise due to varying construction conditions and environments. For instance, when the bearing stratum of the engineering pile is located in sandy soil with a thin layer of shallow clay, excessively rapid pile driving can result in insufficient cohesive soil penetration into the core (although sandy soil can penetrate, its high permeability allows pressurized water to enter the pit). This weakens the soil plugging effect, increasing the risk of core heave during subsequent excavation. Consequently, this can prevent the proper construction of the nearby pile cap and lead to safety issues related to the retaining structure and surrounding environment caused by softening of the pit bottom soil.
[0003] In summary, the problem that this utility model aims to solve is:
[0004] In foundation pit engineering, the core of the engineering pipe piles driven into the soil is prone to sudden surge, which can adversely affect the subsequent foundation pit construction process, such as softening of the foundation pit soil and ground settlement. Summary of the Invention
[0005] The purpose of this utility model is to provide a drainage system for sudden surges in pipe piles within a foundation pit. This drainage system can effectively prevent sudden surges in pipe piles and drain the surged water.
[0006] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:
[0007] A system for draining sudden surges in pipe piles within a foundation pit, the system comprising a concrete sealing body and a water guide pipe, wherein the concrete sealing body is used to seal the upper opening of the pipe core, and the water guide pipe penetrates through the concrete sealing body.
[0008] Furthermore, a bottom sealing plate is installed near the inlet of the water pipe, and the bottom sealing plate forms a partition inside the pipe core, thereby separating a section at the upper opening of the pipe core as an upper sealing section; the concrete sealing body is constructed within the upper sealing section.
[0009] Furthermore, the surge drainage system also includes a temporary sump, which is constructed at the bottom of the foundation pit; a drainage device is also provided for the temporary sump; the drainage device is used to drain the water in the temporary sump out of the foundation pit.
[0010] Furthermore, the drainage device is a drainage pipe equipped with a submersible pump. The submersible pump is installed at one end of the drainage pipe and placed in a temporary sump. The other end of the drainage pipe extends to a pre-constructed drainage ditch outside the foundation pit.
[0011] Furthermore, the surge drainage system also includes an external drainage ditch for the foundation pit, which is constructed on the outside of the foundation pit; the external drainage ditch is used to: when a surge occurs in the core pipe, discharge the surge water in the core pipe into the foundation pit and discharge it into the external drainage ditch.
[0012] Compared with the prior art, the advantages of this invention's surge drainage system are as follows:
[0013] When a sudden surge occurs inside the core, the surged water can be discharged through the water guide pipe (or an external drainage pipe can be connected), thereby preventing the surged water from spreading uncontrollably in the foundation pit and thus avoiding adverse effects on the subsequent foundation pit construction process. Attached Figure Description
[0014] Figure 1 is a schematic diagram of the structure of the in-situ drainage system for pipe piles in the foundation pit according to this utility model;
[0015] Figure 2 is a schematic diagram of the core of the pipe pile in the surge drainage system of this utility model. Detailed Implementation
[0016] First, to facilitate a clear and accurate description of the technical solution later in the text, the following definitions are made in advance:
[0017] Definition 1: The “designed core filling bottom” mentioned in this article refers to the core filling depth specified in the original pile foundation design.
[0018] The specific embodiments of this utility model are further described below:
[0019] This embodiment relates to a foundation pit project in which the "construction of driven pipe piles 15" has been completed at the bottom of the foundation pit, meaning that pipe piles 15 with completed construction work are already present at the bottom of the foundation pit. In order to resolve potential sudden surges within the core 5 of the pipe piles 15, this embodiment provides a method and system for resolving sudden surges within the foundation pit pipe piles. This method and system can effectively prevent sudden surges in the pipe piles 15.
[0020] It should be noted that, in order to facilitate drainage, an external drainage ditch 4 is usually constructed next to the foundation pit project.
[0021] Referring to Figures 1 and 2, specifically, the surge relief method of this embodiment includes steps S1 to S5.
[0022] S1, Construction preparation work.
[0023] S11, the working environment near the pipe pile 15 at the bottom of the foundation pit is cleared by using an excavator to clean up the loose soil near the pipe pile 15.
[0024] S12, excavate and construct a temporary sump pit 1 at the bottom of the foundation pit 2 near the pipe pile 15.
[0025] The purpose of constructing the temporary sump pit 1 is to ensure that when the pipe pile 15 experiences a sudden surge, the water that surges out to the bottom of the foundation pit 2 can be collected in the temporary sump pit 1 and will not spread everywhere, thereby controlling the area of impact of the surged water on the soil at the bottom of the foundation pit 2 and ensuring the safety of the retaining structure 12.
[0026] S13, A drainage device is provided for the temporary water collection pit 1. The drainage device is used to drain the water in the temporary water collection pit 1 into the pre-constructed drainage ditch 4 outside the foundation pit, so as to avoid excessive sudden water flow causing the temporary water collection pit 1 to overflow.
[0027] More specifically, the drainage device is essentially a drainage pipe 13 equipped with a submersible pump 3. The submersible pump 3 is installed at one end of the drainage pipe 13 and is placed in a temporary sump pit 1. The other end of the drainage pipe 13 extends to the drainage ditch 4 outside the foundation pit.
[0028] S14. Clean the core 5 of the pipe pile 15, removing the soil inside the core 5 to prepare for the subsequent construction of the concrete sealing body 9.
[0029] S2, for the core 5 of the pipe pile 15, a water guide pipe 6 is set. The water guide pipe 6 is actually a steel pipe. One end of the water guide pipe 6 is inserted into the core 5 as the water inlet, and the other end of the water guide pipe 6 is exposed on the outside of the core 5 as the water outlet.
[0030] A water pumping device (vacuum pump water pumping pipeline) is also provided at the outlet of the water guide pipe 6. The water pumping device is used to directly pump the water in the core 5 through the water guide pipe 6 into the drainage ditch 4 outside the foundation pit.
[0031] It should be noted that the depth to which the inlet of the water pipe 6 is inserted into the core 5 should exceed the design filler bottom 10 of the pipe pile 15, preferably by more than two meters (i.e., the position of the inlet of the water pipe 6 is more than two meters below the design filler bottom 10). The purpose of this setting is to ensure that when a water pump is used to pump out the water in the core 5, the water level in the core 5 can be effectively reduced to below the filler bottom.
[0032] It should be noted that a disc-shaped sealing plate 8 is installed near the inlet of the water pipe 6 by welding. The dimensions of the sealing plate 8 are consistent with the inner diameter of the core 5 of the pipe pile 15, and the sealing plate 8 is perpendicular to the water pipe 6.
[0033] When the inlet of the water pipe 6 is inserted into the core 5, the bottom sealing plate 8 forms a partition inside the core 5, dividing the internal space of the core 5 into two sections. For ease of description, the section inside the core 5 below the bottom sealing plate 8 is defined as the lower main core section (as indicated by arrow A2 in the figure), and the section inside the core 5 above the bottom sealing plate 8 is defined as the upper sealing section (as indicated by arrow A1 in the figure).
[0034] The upper sealing section will be used to construct the concrete sealing body 9. In other words, the purpose of setting the bottom sealing plate 8 is to separate an upper sealing section at the upper opening of the core 5, thereby creating conditions for the subsequent construction of the concrete sealing body 9.
[0035] It should be noted that when inserting the water pipe 6 into the core 5, the bottom sealing plate 8 should be below the designed core filling bottom 10. The purpose of this setting is to ensure that the subsequently constructed concrete sealing body 9 can reach below the designed core filling bottom 10, so that when a sudden surge occurs in the core 5, the water level of the surged water will not be higher than the designed core filling bottom 10.
[0036] Preferably, the position of the bottom sealing plate 8 should be at least 0.5 meters lower than the designed core filling bottom 10.
[0037] S3, a pumping device is used to pump water from the lower main core section of the core 5 through the water pipe 6, so that the water level in the core 5 drops below the bottom sealing plate 8.
[0038] S4. The pre-constructed anchoring steel bars 11 are placed in the upper sealing section of the core pipe 5. Then, concrete (rapid-hardening expansive concrete) is poured into the upper sealing section, thereby constructing a reinforced concrete solid structure in the upper sealing section of the core pipe 5. This reinforced concrete solid structure serves to seal the upper opening of the core pipe 5, and is therefore named the concrete sealing body 9. The concrete sealing body 9, like a plug, seals the upper opening of the core pipe 5, leaving only a water guide pipe 6 to pass through. Any sudden surge of water generated inside the core pipe 5 can only leave the core pipe 5 through the water guide pipe 6.
[0039] It should be noted that the anchoring steel bar 11 refers to the main steel bar in the steel cage in the original design structure, which extends a certain length beyond the top of the pipe pile 15 to ensure that it effectively connects the pipe pile 15 to the bottom plate.
[0040] S5. After the concrete sealing body 9 has reached the required strength (80% of the design strength), the pumping device will be removed, leaving the water pipe 6 intact. The water pipe 6 will be completely sealed during the subsequent construction of the base slab.
[0041] This embodiment also provides a surge drainage system, which includes the previously mentioned concrete sealing body 9, water pipe 6, temporary sump 1, external drainage ditch 4, drainage device and pumping device, etc. The surge drainage system is constructed based on the previously mentioned surge drainage method, and for details, please refer to the previous surge drainage method.
[0042] The advantages of the surge drainage method and system of this embodiment are:
[0043] 1) A water guide pipe 6 is installed for the core 5 of the pipe pile 15, and a concrete sealing body 9 is constructed at the upper opening of the core 5 to block the upper opening of the core 5. In this way, when a sudden surge occurs in the core 5, the surge water in the core 5 can be discharged through the water guide pipe 6 (and can also be connected to an external drainage pipe), thereby preventing the surge water from spreading rampantly in the foundation pit and thus avoiding adverse effects on the subsequent foundation pit construction process.
[0044] 2) The surge drainage method and system of this embodiment are economical, convenient, green and environmentally friendly to implement, and the construction process is simpler, with significant overall effects.
[0045] The following is a brief introduction to the initial concept of the surge relief method and system of this utility model:
[0046] 1) First, use an excavator to clear the loose soil near the pipe pile 15. At the same time, dig a temporary sump pit 1 near the pipe pile 15 to ensure that the gushing confined water flows to the temporary sump pit 1 at the bottom of the foundation pit 2, so as to prevent the confined water from spreading everywhere, thereby controlling the area of impact of the confined water on the soil at the bottom of the foundation pit 2, and ensuring the safety of the retaining structure 12.
[0047] 2) The size of the temporary sump pit 1 should be moderate, not too large or too deep, to prevent the temporary sump pit 1 from collapsing or reduce the softening of the soil at the bottom 2 of the surrounding foundation pit; a submersible pump 3 of appropriate power should be installed in the temporary sump pit 1 to effectively discharge the pressurized water in the temporary sump pit 1 into the drainage ditch 4 outside the foundation pit.
[0048] 3) Clean the soil inside the core 5 of the pipe pile 15, insert the water guide pipe 6 into the core 5 of the pipe pile 15, and insert it to a depth of at least 2m below the design fill bottom 10 of the pipe pile 15 to ensure that the water level of the pressurized water head 7 inside the core 5 can be effectively reduced to below the fill bottom.
[0049] The water guide pipe 6 that enters the core 5 is made of steel pipe, and a bottom sealing plate 8 is welded on the steel pipe. The size of the bottom sealing plate 8 is the same as that of the core 5, so that the bottom sealing plate 8 can effectively seal the core 5, thereby ensuring that the subsequent pouring of fast-hardening expansion concrete is retained within a certain range of the designed core filling bottom 10.
[0050] The depth of the bottom slab 8 should be at least 0.5m lower than the design filling bottom 10 of the pipe pile 15 to ensure that the actual filling depth is not less than the design filling depth. The water guide pipe 6 should be connected to the drainage ditch 4 outside the foundation pit.
[0051] 4) After the pressure head 7 in the core 5 drops below the bottom plate 8, insert the anchoring steel bar 11, and then promptly pour the core 5 of the pipe pile 15 with fast-hardening expansion concrete.
[0052] 5) After the rapid-hardening expansion concrete reaches 80% of the design strength, remove the vacuum pump, leaving the water pipe 6 intact, to be sealed during the subsequent foundation slab construction.
[0053] The above are merely preferred embodiments of the present utility model and are not intended to limit the scope of protection of the present utility model. Therefore, any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the scope of protection of the present utility model.
Claims
1. A system for draining sudden water inflow from pipe piles in a foundation pit, characterized in that: The surge drainage system includes a concrete sealing body (9) and a water guide pipe (6). The concrete sealing body (9) is sealed at the upper opening of the core (5) of the pipe pile (15), and the water guide pipe (6) penetrates through the concrete sealing body (9).
2. The inrush drainage system for pipe piles in the foundation pit according to claim 1, characterized in that: A bottom sealing plate (8) is provided near the inlet of the water pipe (6). The bottom sealing plate (8) forms a partition inside the core (5), thereby separating a section at the upper opening of the core (5) as an upper sealing section; the concrete sealing body (9) is constructed in the upper sealing section.
3. The inrush drainage system for pipe piles in the foundation pit according to claim 1, characterized in that: The surge drainage system also includes a temporary sump (1), which is constructed at the bottom (2) of the foundation pit; a drainage device is also provided for the temporary sump (1); the drainage device is used to drain the water in the temporary sump (1) from the foundation pit.
4. The inrush drainage system for pipe piles in the foundation pit according to claim 3, characterized in that: The drainage device is a drainage pipe (13) equipped with a submersible pump (3). The submersible pump (3) is installed at one end of the drainage pipe (13) and is placed in a temporary sump (1). The other end of the drainage pipe (13) extends to a pre-constructed drainage ditch (4) outside the foundation pit.
5. The inrush drainage system for pipe piles in the foundation pit according to claim 1, characterized in that: The surge drainage system also includes an external drainage ditch (4) for the foundation pit, which is constructed on the outside of the foundation pit. The external drainage ditch (4) is used to discharge the surge water in the core (5) into the foundation pit and into the external drainage ditch (4) when a surge occurs in the core (5).