Landscape pier precast pile in waterfront soft soil area and construction method

Abstract

A waterfront soft soil area landscape pier precast pile comprises a concrete precast pile, the concrete precast pile comprises a pile top, a pile body and a pile tip, a steel reinforcement framework is arranged in the concrete precast pile, a drainage system and a grouting reinforcement system are arranged in the concrete precast pile, and the waterfront soft soil area landscape pier precast pile comprises a grouting pipe which longitudinally penetrates through the pile body from the pile top to the position above the pile tip. The top end of the grouting pipe extends out of the surface of the pile top to facilitate later grouting, the surface of the grouting pipe is connected with a grouting pipe branch pipe, the grouting pipe branch pipe extends out of the surface of the pile body in the radial direction, an included angle of 10-20 degrees is downwards formed between the grouting pipe branch pipe and the surface of the grouting pipe, and grout is sprayed along the inclined angle to form a mushroom-shaped reinforcing area to completely wrap the lower middle portion of the pile body. And the reinforcing area and the pile body form an integral collaborative stress body, so that the pile end resistance is further improved, and meanwhile, continuous consolidation settlement caused by excess pore water pressure is inhibited.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of foundation treatment, in particular to a landscape bridge pier precast pile in a waterfront soft soil area and a construction method. BACKGROUND

[0002] Although the traditional reinforced concrete precast pile performs well in general stratum, when applied to the waterfront soft soil area, the pile-soil interface frictional resistance is sharply reduced and the single pile bearing capacity is decreased due to the high natural water content of the soft soil, which is 45% to 85%, so that the load demand of the landscape bridge cannot be met; meanwhile, the excess pore water pressure causes continuous consolidation settlement, and the post-construction settlement is generally large, which causes the bridge pier to be inclined and cracked.

[0003] The existing improvement schemes such as the drainage consolidation method have low drainage efficiency due to the extremely low permeability coefficient of the soft soil; the pile tip grouting technology has a small grout diffusion radius due to the dilution effect of underground water, and the pile side frictional resistance is not obviously improved; the composite foundation treatment is limited by the difficulty of mechanical access in the waterfront area, and the pile quality has large discreteness, and the settlement control compliance rate is only 50% to 60%.

[0004] The existing concrete precast pile lacks the integrated drainage function, cannot actively reduce the water content of the soil around the pile, and the grouting system is separated from the pile body structure, so that the collaborative reinforcement body cannot be formed; these defects directly lead to insufficient bearing capacity and uncontrolled settlement, and become the bottleneck restricting the construction of the waterfront landscape bridge. SUMMARY

[0005] In order to solve the above problems, the application provides a landscape bridge pier precast pile in a waterfront soft soil area and a construction method.

[0006] The landscape bridge pier precast pile in the waterfront soft soil area comprises a concrete precast pile, the concrete precast pile comprises a pile top, a pile body and a pile tip, a steel reinforcement cage is arranged in the concrete precast pile, and a drainage system and a grouting reinforcement system are arranged in the concrete precast pile;

[0007] Further, the grouting reinforcement system comprises a grouting pipe, the grouting pipe longitudinally penetrates the pile body from the pile top to the upper side of the pile tip, the top end of the grouting pipe extends out of the surface of the pile top to facilitate later grouting, a grouting pipe branch pipe is connected to the surface of the grouting pipe, the grouting pipe branch pipe extends radially out of the surface of the pile body, a circular hole is formed in the end of the grouting pipe branch pipe, a one-way valve plate is arranged in the circular hole, and a downward angle of 10° to 20° is formed between the surface of the grouting pipe branch pipe and the surface of the grouting pipe.

[0008] Further, the steel reinforcement cage comprises a plurality of vertical steel bars uniformly distributed along the circumferential direction of the concrete precast pile, the top end of the vertical steel bar extends out of the pile top, the bottom end of the vertical steel bar is bent 40°-50° towards the center line of the pile tip, and then intersects with the center line of the pile tip or the extension line of the center line of the pile tip, and then is connected with the center steel bar inside the pile tip by welding to form a whole, thereby ensuring the structural strength of the tip and the pile body.

[0009] Further, the steel reinforcement cage further comprises a stirrup, the stirrup spirally winds around the vertical steel bar and is fixed by steel wire binding, the spiral stirrup comprises a conventional section and an encryption section, the conventional section is wound around the middle and lower part of the pile body, and the pitch is 150mm-250mm, and the encryption section is wound around the upper part of the pile body, and the pitch is 50mm-150mm.

[0010] Further, the drainage system comprises a water collecting bin arranged inside the pile body, a water pumping pipe is detachably arranged in the water collecting bin, one end of the water pumping pipe extends into the bottom of the water collecting bin, the other end of the water pumping pipe is connected with a water pumping device, the water collecting bin is a steel cylinder, a water level sensor is arranged inside the water collecting bin to detect the water level inside the water collecting bin, thereby reminding the construction personnel to timely drain water and avoiding excessive drainage to cause surrounding settlement.

[0011] Further, the drainage system further comprises a filtering component, the filtering component comprises a water collecting filter pipe arranged inside the concrete precast pile, one end of the water collecting filter pipe extends into the water collecting bin and is flush with the inner wall surface of the water collecting bin, the other end of the water collecting filter pipe penetrates through the outer surface of the pile body and is flush with the end surface of the water collecting filter pipe, and the upper water collecting filter pipe and the lower water collecting filter pipe are respectively arranged on the upper part and the lower part of the pile body.

[0012] Further, the water collecting bin comprises a pipe body, a water outlet and a water collecting opening are respectively arranged at two ends of the pipe body, a water collecting cavity is arranged at one end of the pipe body provided with the water collecting opening, and a water outlet cavity is arranged at one end of the pipe body provided with the water outlet.

[0013] Further, when the concrete precast pile is pressed into the soft soil layer, the water in the soil layer enters the water collecting cavity through the water collecting opening and flows into the water outlet cavity after being filtered, when the water amount in the water outlet cavity is accumulated enough, the water flow pushes away the water stop flap to enter the water collecting bin and is pumped out.

[0014] Further, the water outlet is provided with a water stop flap, the water collecting opening is provided with a filter plate, and the filter plate limits the entry of large-particle impurities.

[0015] Further, filter layers are arranged inside the pipe body in the direction away from the soft soil layer, a partition plate is arranged between the filter layers, and a blocking net is arranged inside the pipe body, the filter layers are arranged according to the specific construction environment to filter the water flow, thereby avoiding that the impurities block the water pumping pipe, and the filter layers are selected according to the specific construction condition, common filter materials are selected, or only a coarse filtering area is arranged in the water collecting cavity and is filled with gravel to block the large-particle impurities.

[0016] Further, the grouting pipes are uniformly distributed along the circumferential direction of the concrete precast pile to ensure uniform grouting.

[0017] A construction method of a waterfront soft soil area landscape bridge pier precast pile, comprising the following steps:

[0018] Step S1: precast pile production, the concrete precast pile is produced in a factory;

[0019] Steel cage binding: C25 vertical reinforcement, spacing 150mm and C10 stirrup, spacing 100mm, reserved grouting pipe, water pump interface.

[0020] Water collecting chamber pouring: in the middle of the pile body, 3-5m below the ground, pre-burying a water collecting chamber with a volume of 0.5m 3 , connecting the water pump.

[0021] Filter pipe installation: installing a water collecting filter pipe in the range of 1-8m above the pile tip, and filling filter materials such as filter cloth, sand and gravel, and activated carbon in the water collecting filter pipe.

[0022] Step S2: preparation before pile sinking, on-site pretreatment;

[0023] Measurement and lofting: GPS positioning, controlling the perpendicularity ≤0.5%.

[0024] Step S3: static pressure pile sinking;

[0025] Pile pressing sequence: advancing from the river to the land to avoid the soil squeezing effect causing the completed pile to float up.

[0026] Dynamic monitoring: through the detachable monitoring device on the pile top, the inclination sensor cooperates with the pressure gauge to adjust the pile pressing force in real time, and the pile pressing force is controlled at 1500-2000kN, and when hard interlayer is encountered, the pile tip vibration auxiliary system is started.

[0027] Key control: when the pile tip enters the aquifer, about 5-8m underground, the specific situation needs to be determined according to the specific construction situation, the water stop flap opens under the water flow pressure, and the groundwater starts to flow into the water collecting cavity.

[0028] Step S4: water collecting and pumping; pumping stage: after the pile sinking is completed, the water pump is connected to the vacuum pump station immediately, the vacuum degree is-0.08MPa, and the pumping is continued for 72h, so that the water content of the soft soil around the pile is reduced to below 40%.

[0029] Intelligent control: when the water level of the water collecting chamber is <0.2m, the water pump is automatically turned off to avoid excessive drainage leading to surrounding settlement.

[0030] Step S5: high pressure grouting;

[0031] Grouting parameters: cement slurry P.O42.5+5% expansion agent, grouting 2.5-3.0 MPa, single pile grouting amount (m 3 ) = pile diameter (m) x pile length (m) x 0.2.

[0032] Sequence: stratified grouting from bottom to top, 1 section every 2 m, after the slurry outlet one-way port breaks through the soil layer, a "mushroom-shaped" slurry diffusion zone is formed.

[0033] Quality control: the grouting amount reaches the design value and the pressure is stable for 5 min, the grouting is terminated, and the one-way port is automatically closed to prevent backflow.

[0034] Step S6: construction of the pile cap and the pier column;

[0035] Pile top treatment: chiseling the pile top to expose the vertical reinforcement, installing the prefabricated pile cap, matching the positioning tenon, and pouring C40 micro-expansion concrete.

[0036] Compared with the prior art, the application has the following beneficial effects:

[0037] The pile body is pre-buried with a water collecting chamber and upper and lower water collecting and filtering pipes to form an active drainage channel. When the pile is sunk, the soft soil pore water enters the water collecting cavity through the multi-layer filtering layer and is pumped and discharged by the vacuum pump, thereby reducing the water content of the soil layer, increasing the effective stress of the soil body after drainage, accelerating the consolidation settlement, improving the pile side friction, and meeting the load demand of the landscape bridge.

[0038] The grouting pipe branch penetrates the pile body at a downward inclination angle of 10°-20°, and realizes directional high-pressure grouting in cooperation with the one-way valve plate. The slurry is sprayed along the inclination angle to form a mushroom-shaped reinforcement zone, which completely wraps the middle and lower parts of the pile body. The reinforcement zone and the pile body form an integral force body, which further improves the pile end resistance and simultaneously suppresses the sustained consolidation settlement caused by the excess pore water pressure. BRIEF DESCRIPTION OF DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or prior art description. Obviously, for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0040] Figure 1 It is a top view of the prefabricated pile;

[0041] Figure 2 It is a schematic view of the prefabricated pile structure;

[0042] Figure 3 It is a schematic view of the reinforcement structure;

[0043] Figure 4 It is a schematic view of the installation position of the drainage pipe;

[0044] Figure 5 is a schematic view of the structure of the grouting pipe;

[0045] Figure 6 is a sectional view of the structure of the drain pipe;

[0046] Figure 7 is a schematic view of the installation state of the precast pile;

[0047] Figure 8 is a schematic view of the structure of the filter pipe.

[0048] In the figure:

[0049] 1, pile top;

[0050] 2, vertical steel bar;

[0051] 3, stirrup;

[0052] 4, grouting pipe;

[0053] 5, water collecting chamber;

[0054] 6, water pumping pipe;

[0055] 7, grouting pipe branch pipe;

[0056] 8, pile body;

[0057] 9, lower water collecting filter pipe;

[0058] 11, pile tip;

[0059] 12, upper water collecting filter pipe;

[0060] 13, one-way grouting outlet;

[0061] 14, water stop flap;

[0062] 15, water outlet;

[0063] 16, water outlet cavity;

[0064] 17, filter layer;

[0065] 21, water collecting cavity;

[0066] 22, water collecting port;

[0067] 23, filter plate;

[0068] 24, intercepting net;

[0069] 25, partition plate;

[0070] 26, pipe body;

[0071] 27, coarse filter area;

[0072] 28, concrete precast pile;

[0073] 29, reinforcement zone;

[0074] 30, soft soil layer. DETAILED DESCRIPTION

[0075] In order to make the objects, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and not used to limit the present application.

[0076] The application principle of the present application will be further described below with reference to the drawings and specific embodiments.

[0077] Embodiment 1

[0078] As shown in Figure 2 , Figure 5 , Figures 6-7 A landscape pile for a waterfront soft soil area bridge pier is provided, which comprises a concrete precast pile 28, the concrete precast pile 28 comprises a pile top 1, a pile body 8 and a pile tip 11, a reinforcing cage is arranged inside the concrete precast pile 28, and a drainage system and a grouting reinforcement system are arranged inside the concrete precast pile 28.

[0079] The grouting reinforcement system comprises a grouting pipe 4, the grouting pipe 4 longitudinally penetrates the pile body 8 from the pile top 1 to a position 1m-2m above the pile tip 11, grouting pipe branch pipes 7 are connected to the surface of the grouting pipe 4, the grouting pipe branch pipes 7 are distributed in a radial manner, so that the reinforcement zone formed during grouting can completely wrap the concrete precast pile 28, the grouting pipe branch pipes 7 radially extend out of the surface of the pile body 8, and a one-way grouting outlet 13 is arranged at the end of the grouting pipe branch pipes 7, the one-way grouting outlet 13 comprises a circular hole arranged at the end of the grouting pipe branch pipes 7, a one-way valve plate is arranged in the circular hole, and a downward angle of 10°-20° is formed between the surface of the grouting pipe branch pipes 7 and the grouting pipe 4, so that the grouting liquid is sprayed along the inclination of the grouting pipe branch pipes 7 during grouting, a mushroom-shaped reinforcement zone 29 is formed, the concrete precast pile 28 is completely wrapped, secondary reinforcement is formed, the pile-soil interface friction is enhanced, the bearing capacity of the landscape pile for the waterfront soft soil area bridge pier is ensured, the construction settlement risk is reduced, and the overall work efficiency is improved.

[0080] Embodiment 2

[0081] As shown in Figures 1-8 A landscape pile for a waterfront soft soil area bridge pier is provided, which comprises a concrete precast pile 28, the concrete precast pile 28 comprises a pile top 1, a pile body 8 and a pile tip 11, a reinforcing cage is arranged inside the concrete precast pile 28, and a drainage system and a grouting reinforcement system are arranged inside the concrete precast pile 28.

[0082] The grouting reinforcement system comprises a grouting pipe 4, which longitudinally penetrates the pile top 1, the pile body 8 and the pile tip 11, and the top end of the grouting pipe 4 extends out of the surface of the pile top 1 to facilitate later grouting, and the surface of the grouting pipe 4 is connected with a grouting pipe branch pipe 7, which extends radially out of the surface of the pile body 8, and the end of the grouting pipe branch pipe 7 is provided with a circular hole, and a one-way valve plate is arranged in the circular hole, and the grouting pipe branch pipe 7 and the surface of the grouting pipe 4 form an angle of 10°-20° downward, and when grouting, the slurry is sprayed along the inclination of the grouting pipe branch pipe 7, and after the slurry is sprayed, part of the slurry moves along the surface of the pile body 8, and the other part of the slurry extends horizontally after encountering the hard soil layer, and finally a mushroom-shaped reinforced area 29 is formed.

[0083] The steel reinforcement cage comprises a plurality of vertical steel bars 2 which are uniformly distributed along the circumferential direction of the concrete precast pile 28, the top end of the vertical steel bar 2 extends out of the pile top 1, the bottom end of the vertical steel bar 2 is bent by 40°-50° towards the center line direction of the pile tip 11, and intersects with the center line of the pile tip 11 or the extension line of the center line of the pile tip 11, and then is connected with the central steel bar inside the pile tip 11 through welding to form a whole, thereby ensuring the structural strength of the pile tip 11 and the pile body 8.

[0084] The steel reinforcement cage further comprises a stirrup 3 which is spirally wound around the vertical steel bar 2 and is fixed through steel wire binding, and the spirally wound stirrup 3 comprises a conventional section and an encryption section, the conventional section is wound on the middle and lower part of the pile body 8, and the pitch thereof is 150mm-250mm, and the encryption section is wound on the upper part of the pile body 8, and the pitch thereof is 50mm-150mm.

[0085] The drainage system comprises a water collecting bin 5 arranged inside the pile body 8, and a water pumping pipe 6 is detachably arranged inside the water collecting bin 5, one end of the water pumping pipe 6 extends into the bottom of the water collecting bin 5, and the other end is connected with a water pumping device, the water collecting bin 5 is a steel cylinder, a water level sensor is arranged inside the water collecting bin 5 to detect the water level inside the water collecting bin 5, thereby reminding the construction personnel to timely drain water and avoiding excessive drainage to cause surrounding settlement.

[0086] Further comprising a filtering component, the filtering component comprises a water collecting filter pipe arranged inside the concrete precast pile 28, one end of the water collecting filter pipe extends into the water collecting bin 5 and is flush with the inner wall surface of the water collecting bin 5, and the other end of the water collecting filter pipe penetrates the outer surface of the pile body 8 and is flush with the end surface of the water collecting filter pipe, and the upper water collecting filter pipe 12 and the lower water collecting filter pipe 9 are respectively arranged on the upper and lower parts of the pile body 8.

[0087] The water collecting bin 5 comprises a pipe body 26, and the pipe body 26 is provided with a water outlet 15 and a water collecting opening 22 at both ends, respectively, one end of the pipe body 26 provided with the water collecting opening 22 is provided with a water collecting cavity 21, and one end of the pipe body 26 provided with the water outlet 15 is provided with a water outlet cavity 16.

[0088] When the concrete precast pile 28 is pressed into the soft soil layer 30, the water in the soil layer enters the water collecting cavity 21 through the water collecting port 22 and flows into the water outlet cavity 16 after being filtered, and when the water in the water outlet cavity 16 accumulates enough, the water flow pushes away the water stop flap 14 to enter the water collecting bin 5 and waits to be pumped out.

[0089] The water outlet 15 is provided with a water stop flap 14, and the water collecting port 22 is provided with a filter plate 22, which limits the entry of large-particle impurities.

[0090] The filter layer 17 is arranged inside the pipe body 26 in a direction away from the soft soil layer 30, and the pipe body 26 is provided with a partition plate 25, and the surface of the partition plate 25 is provided with a blocking net 24. According to the need, the filter layer is arranged to filter the water flow, so as to avoid that the impurities block the water pump 6. The filter layer is selected according to the specific construction condition, or only a coarse filter area 27 is arranged in the water collecting cavity 21, and the coarse filter area 27 is filled with gravel, so as to block large-particle impurities.

[0091] The grouting pipe 4 is uniformly distributed along the circumferential direction of the concrete precast pile 28, so as to ensure uniform grouting.

[0092] Example 3

[0093] A construction method of a waterfront soft soil area landscape bridge pier precast pile, comprising the following steps:

[0094] Step S1: precast pile production, the concrete precast pile 28 is produced in a factory;

[0095] Steel reinforcement cage binding: C25 vertical reinforcement, spacing 150mm and C10 stirrup, spacing 100mm, pre-reserved grouting pipe 4 and water pump 6 interface.

[0096] Water collecting bin pouring: in the middle of the pile body, at the position of 3-5m below the ground, pre-burying a water collecting bin 5 with a volume of 0.5m 3 , and connecting the water pump 6.

[0097] Filter pipe installation: installing a water collecting filter pipe in the range of 1-8m above the pile tip, and filling filter materials such as filter cloth, sandstone and activated carbon in the water collecting filter pipe.

[0098] Step S2: preparation before pile sinking, on-site pretreatment;

[0099] Measurement and lofting: GPS positioning, controlling the perpendicularity to be less than or equal to 0.5%.

[0100] Step S3: static pressure pile sinking;

[0101] Pile pressing sequence: advancing from the river to the land to avoid the soil squeezing effect causing the completed pile to float up.

[0102] Dynamic monitoring: through the detachable monitoring device on the pile top, the inclination sensor cooperates with the pressure gauge to adjust the pile pressing force in real time, and the pile pressing force is controlled at 1500-2000kN, and when the hard interlayer is encountered, the pile tip vibration auxiliary system is started.

[0103] Key control: when the pile tip enters the aquifer, about 5-8m underground, the specific situation needs to be determined according to the specific construction situation, the water stop flap 14 is opened under the water flow pressure, and the groundwater starts to flow into the water collecting cavity 21.

[0104] Step S4: water collection and pumping; pumping stage: immediately after the pile sinking is completed, the water pumping pipe 6 is connected to the vacuum pump station, the vacuum degree is-0.08MPa, and the pumping is continued for 72h, so that the water content of the soft soil around the pile is reduced to below 40%.

[0105] Intelligent control: when the water level in the water collecting bin 5 is less than 0.2m, the water pump is automatically turned off to avoid excessive drainage and cause surrounding settlement.

[0106] Step S5: high-pressure grouting;

[0107] Grouting parameters: cement slurry P.O42.5+5% expansion agent, grouting pressure 2.5-3.0MPa, single pile grouting amount (m 3 ) = pile diameter (m) x pile length (m) x 0.2.

[0108] Sequence: layered grouting from bottom to top, every 2m as a section, after the grouting one-way port 13 breaks through the soil layer, a "mushroom-shaped" grouting diffusion zone is formed.

[0109] Quality control: when the grouting amount reaches the design value and the pressure is stable for 5min, the grouting is terminated, and the one-way port is automatically closed to prevent backflow.

[0110] Step S6: construction of the bearing platform and the pier column;

[0111] Pile top treatment: roughening the pile top 1, exposing the vertical steel bars (2), installing the prefabricated bearing platform, matching the positioning tenon, and pouring C40 micro-expansion concrete.

[0112] It is apparent to those skilled in the art that the present application is not limited to the details of the foregoing exemplary embodiments, but can be implemented in other concrete forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and not restrictive, the scope of the present application being defined by the appended claims rather than the foregoing description, and it is intended to encompass all changes falling within the meaning and scope of the equivalent elements of the claims.

[0113] Furthermore, it should be understood that although the specification is described in terms of embodiments, not every embodiment includes every feature or implementation described herein. The specification can include implicit combinations of explicitly mentioned features and / or implicit combinations of implicitly mentioned features. Such combinations are also expressly included within the scope of the specification and an embodiment.

Claims

1. A prefabricated pile for landscape bridge piers in waterfront soft soil areas, characterized by: The concrete precast pile (28) comprises a pile top (1), a pile body (8) and a pile tip (11); a steel frame is provided inside the concrete precast pile (28); and a drainage system and a grouting reinforcement system are provided inside the concrete precast pile (28); The grouting reinforcement system comprises a grouting pipe (4), wherein the grouting pipe (4) longitudinally penetrates the pile body (8) from the pile top (1) to the top of the pile tip (11), a grouting pipe branch (7) is connected to the surface of the grouting pipe (4), the grouting pipe branch (7) radially extends out of the surface of the pile body (8), a circular hole is opened at the end of the grouting pipe branch (7), a one-way valve plate is arranged in the circular hole, and an angle of 10° to 20° is formed downwardly between the grouting pipe branch (7) and the surface of the grouting pipe (4). During grouting, the slurry is sprayed out along the inclination angle of the grouting pipe branch (7) to form a reinforcement area (29).

2. The precast pile for landscape bridge piers in waterfront soft soil areas according to claim 1 is characterized by: The steel bar skeleton comprises a plurality of vertical steel bars (2) uniformly distributed along the circumference of the precast concrete pile (28), the top ends of the vertical steel bars (2) extending out of the pile top (1), the bottom ends of the vertical steel bars (2) being bent 40° to 50° toward the center line of the pile tip (11) and intersecting at the center line of the pile tip (11) or an extension of the center line of the pile tip (11).

3. The prefabricated piles for landscape bridge piers in waterfront soft soil areas according to claim 2 are characterized by: The steel skeleton further comprises stirrups (3), the stirrups (3) being spirally wound around the vertical steel bars (2), the spiral stirrups (3) comprising a conventional section and a denser section, the conventional section being wound around the middle and lower part of the pile body (8) with a pitch of 150 mm to 250 mm, and the denser section being wound around the upper part of the pile body (8) with a pitch of 50 mm to 150 mm.

4. The prefabricated piles for landscape bridge piers in waterfront soft soil areas according to claim 1 are characterized by: The drainage system comprises a water collection bin (5) arranged inside the pile body (8), a water pumping pipe (6) is detachably installed inside the water collection bin (5), one end of the water pumping pipe (6) extends into the bottom of the water collection bin (5), and the other end is connected to a water pumping device.

5. The prefabricated piles for landscape bridge piers in waterfront soft soil areas according to claim 1 are characterized by: The invention also includes a filtering component, which includes a water collection filter pipe arranged inside the concrete precast pile (28), one end of the water collection filter pipe extends into the water collection bin (5) and is flush with the inner wall surface of the water collection bin (5), and the other end of the water collection filter pipe penetrates the outer surface of the pile body (8), and the end surface of the water collection filter pipe is flush with the outer surface, and is respectively installed on the upper and lower parts of the pile body (8).

6. The prefabricated piles for landscape bridge piers in waterfront soft soil areas according to claim 5 are characterized by: The water collecting bin (5) comprises a tube body (26), and both ends of the tube body (26) are respectively provided with a water outlet (15) and a water collecting port (22); the end of the tube body (26) provided with the water collecting port (22) is provided with a water collecting cavity (21), and the end of the tube body (26) provided with the water outlet (15) is provided with a water outlet cavity (16).

7. The precast pile for landscape bridge piers in waterfront soft soil areas according to claim 6, characterized in that: A water-stop flap (14) is installed at the water outlet (15), and a filter plate (22) is installed at the water collection port (22).

8. The precast piles for landscape bridge piers in waterfront soft soil areas according to claim 6 are characterized by: Filter layers (17) are sequentially arranged inside the tube body (26) in a direction away from the soft soil layer (30), a partition (25) is arranged inside the tube body (26), and an interception net (24) is installed on the surface of the partition (25).

9. The precast piles for landscape bridge piers in waterfront soft soil areas according to claim 1 are characterized by: The grouting pipes (4) are evenly distributed along the circumference of the precast concrete piles (28).

10. A construction method for precast piles of landscape bridge piers in waterfront soft soil areas, comprising the precast piles of landscape bridge piers in waterfront soft soil areas according to any one of claims 1 to 9, characterized in that: Features include: Step S1: Prefabricated pile production: tie the steel skeleton in the prefabrication factory, and reserve the interfaces of the grouting pipe (4) and the pumping pipe (6); pouring the water collection bin: in the middle of the pile body, 3-5m below the ground, pre-buried the water collection bin (5) connected to the pumping pipe 6; filter pipe installation: install the water collection filter pipe in the range of 1-8m above the pile tip, and fill the water collection filter pipe with filter material; Step S2: Preparation before pile sinking: pre-processing on site, measurement and setting out: GPS positioning, control verticality ≤ 0.5%; Step S3: static pressure pile sinking; pile driving sequence: advancing from the river channel to the land to avoid the soil squeezing effect that causes the completed pile to float up; dynamic monitoring: through the detachable monitoring device on the pile top, the inclination sensor and the pressure gauge, the pile driving force is adjusted in real time, and the pile driving force is controlled at 1500-2000kN. When encountering a hard interlayer, it is paused and the pile tip vibration auxiliary system is started; key control: when the pile tip enters the aquifer, 5-8m underground, the water stop flap (14) opens under the water flow pressure, and the groundwater begins to flow into the water collection tank (5); Step S4: water collection and drainage; drainage phase: after the pile is sunk, the water pipe (6) is immediately connected to the vacuum pump station, and the drainage is continued for 72 hours to ensure that the moisture content of the soft soil around the pile is reduced to below 40%; when the water level in the water collection bin (5) is less than 0.2m, the water pump is automatically turned off to avoid excessive drainage and surrounding settlement; Step S5: high pressure grouting; secondary reinforcement; grouting parameters: cement slurry P.O42.5+5% expansion agent, grouting 2.5-3.0MPa, single pile grouting volume (m 3 ) = pile diameter (m) × pile length (m) × 0.2; Sequence: Grouting is carried out in layers from bottom to top, with each 2m as one section. After the grouting outlet breaks through the soil layer, a "slurry diffusion zone" is formed. Quality control: When the grouting volume reaches the designed value and the pressure is stable for 5 minutes, grouting is terminated and the grouting outlet is automatically closed to prevent backflow. Step S6: Construction of the pier and the pier; Pile top treatment: roughening the pile top (1) to expose the vertical reinforcement (2), installing the prefabricated pier, matching the positioning tenon, and pouring concrete.

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