A pouring sleeve and a water permeable concrete pile made of the pouring sleeve and a manufacturing and using method thereof

Abstract

A casting sleeve and the permeable concrete pile made from it, as well as methods for manufacturing and using the pile. This invention discloses a casting sleeve for a permeable concrete pile with combined electro-osmotic drainage, comprising a sleeve and a steel plate. The sleeve is hollow and has a feeding port at the upper end; a cylindrical spiral groove is provided on the outer wall, in which a steel plate slides, with a wire connected to the lower end of the steel plate; a flap-type pile tip is provided at the lower end of the sleeve. A permeable concrete pile includes permeable concrete and a steel plate. A method for manufacturing and using a permeable concrete pile. This invention, through the arrangement of the sleeve and steel plate, forms a permeable concrete pile with combined electro-osmotic drainage. While enhancing the bearing capacity, it can improve drainage efficiency using electro-osmosis; by first energizing the positive and negative electrodes of the permeable group, and then energizing the individual permeable concrete pile in the center, the water in the soil is drained more efficiently due to the electro-osmotic principle; by reducing the interface resistance, the electro-osmotic reinforcement effect is enhanced; and by using the method of translating the positive electrode pile, the problem of drainage blind spots is avoided.

Description

Technical Field

[0001] This invention relates to a casing, specifically to a cast-in-place casing and the permeable concrete piles made from it, as well as the manufacturing and usage methods. Background Technology

[0002] Soft soil is widely distributed along the southern coast of China. As a foundation, it has low strength and large post-construction settlement, which is unfavorable for development and construction. Furthermore, soft soil foundations have a low permeability coefficient, requiring a long drainage consolidation time. In practical engineering, replacement is often used, resulting in high construction costs. If the drainage rate can be accelerated and vertical reinforcements are inserted into the soil to form a composite foundation, the foundation strength can be improved while saving costs.

[0003] Driven cast-in-place piles are constructed using hammer driving or vibratory driving methods. A steel casing with a hinged pile tip or precast reinforced concrete pile shoe is driven into the soil, and then concrete is poured (or a reinforcing cage is placed inside the casing) while the casing is hammered or vibrated and pulled out. Driven cast-in-place pile technology is mature and widely used in engineering applications. Electroosmosis is the phenomenon where a solution flows from the anode to the cathode under the influence of an electric field. The method of treating soft soil foundations using electroosmosis is called electroosmosis. It is very suitable for fine-grained soil layers with a permeability coefficient <0.1 m / d, especially in silt and silty clay. Electroosmosis has strong compatibility, but it has not yet been widely used in practical engineering.

[0004] Among the various methods of electroosmosis, the commonly used energizing mode is the electrode reversal energizing mode, which has many advantages. However, traditional electrode reversal also has two drainage blind zones: the "water flow stagnation zone" and the "zero potential zone." These blind zones increase the drainage path, thereby reducing the efficiency of electroosmosis drainage. The "water flow stagnation zone" occurs before the electrodes are reversed; the water has not yet reached the drainage channel where the cathode is located when the electrodes are reversed, causing the water to return along its original path, resulting in a staggered drainage process that significantly increases the drainage path and reduces the efficiency of electroosmosis drainage. The "zero potential zone" occurs before the electrodes are reversed; even if the soil is very close to the cathode, it is not affected by the electric field, and the potential is essentially zero, so the water in the soil cannot be drained in time. After the electrodes are reversed, the water in this area is affected by the electric field, but it is furthest from the anode.

[0005] Therefore, there is an urgent need for a composite foundation that can combine driven piles with electro-osmosis and avoid the drainage blind spots of electro-osmosis. This would allow the soil and piles to share the load, thereby enhancing the bearing capacity, while the electro-osmosis method can improve drainage efficiency and accelerate soil consolidation. Summary of the Invention

[0006] This invention addresses the shortcomings of existing technologies by providing a cast-in-place casing and the permeable concrete piles made from it, as well as methods for their manufacture and use, to solve the problem of combining driven cast-in-place piles with electro-osmosis for drainage and to avoid drainage blind spots.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A method for manufacturing permeable concrete piles, characterized by comprising the following steps:

[0009] Step 1: Prefabricated sleeve and steel sheet. The outer wall of the sleeve has a cylindrical spiral groove. The steel sheet is screwed into the groove from bottom to top, and a wire is set.

[0010] Step 2: Lower the assembled casing and steel sheet to the designated depth using either hammer piling or vibratory piling.

[0011] Step 3: Pour permeable concrete through the feed port until the mixture inside the casing meets the design requirements of the pile body.

[0012] Step 4: Use the rotating pile pulling device to hold the top of the casing and start the motor. Keep the casing vibrating in place for 10 seconds. Then, while vibrating, use the rotating pipe to pull the casing upwards counterclockwise, leaving the steel sheet in place.

[0013] Step 5: The casing is completely pulled out, completing the pouring of a single permeable concrete pile for combined electro-osmotic drainage.

[0014] To optimize the above technical solution, the specific measures also include:

[0015] Furthermore, the speed of the rotating tube is controlled at 2.2~2.5m / min.

[0016] Furthermore, a method for using permeable concrete piles is characterized by comprising the following steps:

[0017] Step 1: When making permeable concrete piles, six permeable concrete piles are arranged around each permeable concrete pile in the same regular hexagonal ring at equal intervals.

[0018] Step 2: Select seven permeable concrete piles in a regular hexagon as a permeable group, so that the permeable concrete piles form a structure in which multiple permeable groups are connected.

[0019] Step 3: Apply a negative electrode to the steel sheet of each permeable concrete pile located at the center of the regular hexagon, and apply a positive electrode to the six permeable concrete piles around it.

[0020] Step 4: De-energize the permeable concrete pile located at the center of the regular hexagon by connecting the cathode at the upper end and the anode at the lower end through a wire.

[0021] Step 5: Use a water suction device to pump the water that has been drained onto the ground away;

[0022] Step 6, repeat steps 3 to 5 several times;

[0023] Step 7: Taking the permeable concrete pile at the center of the original permeable group's regular hexagon as the target, take the permeable concrete pile at the upper right of the center of the original permeable group's regular hexagon as the center of the new permeable group's regular hexagon, thus completing the reselection of the permeable group.

[0024] Step 8: Repeat steps 3 to 7 until the soil consolidation degree meets the requirements, then stop the power supply.

[0025] Furthermore, step 3 is performed for 2 hours, and step 4 is performed for 1 hour.

[0026] Furthermore, step 5 includes: installing a drainage pipe at the upper end of each permeable concrete pile, and connecting a water pump through the drainage pipe to pump away the water that has been discharged to the ground.

[0027] Furthermore, in step 6, steps 3 to 5 are repeated 6 times.

[0028] The beneficial effects of this invention are:

[0029] This invention forms a permeable concrete pile with combined electro-osmotic drainage by setting up a sleeve and steel sheet. While enhancing the bearing capacity, it can improve drainage efficiency by using electro-osmosis. By first electrifying the positive and negative poles of the permeable group, and then electrifying the central permeable concrete pile individually, the water in the soil is drained more efficiently due to the principle of electro-osmosis. The electro-osmotic reinforcement effect is enhanced by reducing the interface resistance. The problem of drainage blind spots is avoided by using the method of translating the positive pole pile. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of a casting sleeve proposed in this invention;

[0031] Figure 2 This is a partial structural diagram of a casting sleeve proposed in this invention;

[0032] Figure 3 This is a schematic diagram of the groove and steel sheet structure of a casting sleeve proposed in this invention;

[0033] Figure 4 This is a top view of a cross-section of a casting sleeve proposed in this invention;

[0034] Figure 5 This is a flowchart of a method for manufacturing permeable concrete piles proposed in this invention;

[0035] Figure 6 This is a schematic diagram illustrating the energizing principle of the steel sheet in a permeable concrete pile proposed in this invention.

[0036] Figure 7This is a schematic diagram of the pile layout and energization of a permeable concrete pile proposed in this invention;

[0037] Figure 8 This is a schematic diagram of step 7 of a method for using a permeable concrete pile proposed in this invention;

[0038] Figure 9 This is a schematic diagram of the water absorption device for a method of using permeable concrete piles proposed in this invention.

[0039] Reference numerals: 1. Sleeve, 11. Feed port, 12. Wire, 121. Insulation layer, 122. Conductive wire, 13. Groove, 14. Valve-type pile tip, 15. Sleeve wall, 16. Sleeve inner cavity, 2. Steel sheet, 3. Rotary pile pulling device, 4. Water pump, 5. Drainage pipe, 6. Negative pole, 7. Positive pole. Detailed Implementation

[0040] The invention will now be described in further detail with reference to the accompanying drawings.

[0041] It should be noted that the terms such as "upper", "lower", "left", "right", "front", and "back" used in the invention are only for clarity of description and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0042] As attached Figure 1 As shown in the figure, a casting sleeve for a permeable concrete pile with combined electro-osmotic drainage according to an embodiment of the present invention is characterized by: including a sleeve 1 and a steel plate 2; the sleeve 1 is provided with a hollow inner cavity 16; the upper end of the sleeve 1 is provided with a feeding port 11 for pouring concrete into the inner cavity 16; the outer wall of the sleeve wall 15 of the sleeve 1 is provided with a cylindrical spiral groove 13; a cylindrical spiral steel plate 2 that fits the structure of the groove 13 is slidably disposed in the groove 13; the steel plate 2 can only slide within the groove 13 by rotation and cannot be separated horizontally; the lower end of the steel plate 2 is connected to a wire 12 for connecting to a power source; the lower end of the sleeve 1 is provided with a flap-type pile tip 14.

[0043] When the conductive area of ​​the soil is constant, increasing the conductive area of ​​the electrode can reduce the interfacial resistance, increase the soil current, and enhance the electro-osmotic reinforcement effect. The cylindrical spiral steel sheet 2 used in this invention has a smaller interfacial resistance. The permeable concrete pile with combined electro-osmotic drainage cast by the casting sleeve of this invention, as a form of pile foundation, can increase the axial base resistance and improve the axial bearing capacity; and the steel sheet 2 has the additional effects of compressive and tensile resistance.

[0044] In this embodiment, the conductor 12 includes a conductive wire 122, and an insulating layer 121 is sleeved on the outside of the conductive wire 122 to protect the conductive wire 122.

[0045] In this embodiment, the total height of the sleeve 1 can be 1200mm-2000mm higher than the designed permeable concrete pile; the total depth of the groove 13 can be 100mm, wherein the opening of the groove 13 can be 20mm deep and 200mm high, and the inner groove 13 can be 80mm deep and 400mm high; at the same time, the thickness of the steel sheet 2 can be 70mm and the height can be 350mm; the lead of the groove 13 to the cylindrical helix of the steel sheet 2 can be 1500mm; the groove 13 can spiral up from the bottom of the sleeve 1 to a distance of 1200mm from the top, and the conductor 12 is close to the sleeve wall 15 from bottom to a distance of 1400mm from the top of the sleeve 1.

[0046] A permeable concrete pile in this embodiment is characterized by being made using the aforementioned casting sleeve and comprising permeable concrete and steel sheet 2. The permeable concrete pile is a permeable concrete pile combined with electro-osmotic drainage, and is used as a composite foundation.

[0047] In this embodiment, the method for manufacturing a permeable concrete pile described above is characterized by comprising the following steps:

[0048] Step 1: The prefabricated sleeve 1 and steel sheet 2 are screwed into the groove 13 from bottom to top, and the wire 12 is set.

[0049] Step 2: Lower the assembled sleeve 1 and steel sheet 2 to the designated depth using either hammer driving or vibratory driving.

[0050] Step 3: Pour permeable concrete through the feed port 11 until the mixture in the casing 1 meets the design requirements of the pile body.

[0051] Step 4: Use the rotating pile pulling device 3 to hold the top of the casing 1 and start the motor. The casing 1 is left to vibrate in place for 10 seconds. Then, while vibrating, use the rotating pipe pulling device to pull the casing 1 upward counterclockwise, leaving the steel plate 2 in place.

[0052] Step 5: The casing 1 is completely pulled out, completing the pouring of a single permeable concrete pile for combined electro-osmotic drainage.

[0053] In step 4, the speed of rotating the tube to pull it out is controlled at 2.2~2.5 m / min. If silt or silty soil is encountered, the tube pulling speed can be appropriately slowed down. If the material inside the tube sticks and cannot be pulled out during the tube pulling process, the tube wall can be hammered and the tube can be rotated repeatedly.

[0054] The method for using a permeable concrete pile as described above is characterized by the following steps:

[0055] Step 1: When making permeable concrete piles, six permeable concrete piles are set around each permeable concrete pile in the same regular hexagonal ring at equal intervals, and each permeable concrete pile is connected to a power source; in this way, when energized, a structure is formed in which six positive poles 7 surround a negative pole 6 in a ring.

[0056] Step 2: Select seven permeable concrete piles in a regular hexagon as a permeable group, so that the permeable concrete piles form a structure in which multiple permeable groups are connected.

[0057] Step 3: Through conductor 12, negative electricity is applied to the steel sheet 2 of each group of permeable concrete piles located at the center of the regular hexagon, which is called negative pile 6, and positive electricity is applied to the six permeable concrete piles around it, which are called positive piles 7. Since the electric field lines point from the anode to the cathode, and the water flow direction is also the same as the direction of the electric field lines, the water around each group of permeable piles in the soil is diverted to the permeable concrete pile located at the center of the regular hexagon.

[0058] Step 4: De-energize and connect the cathode to the upper end of the permeable concrete pile located at the center of the regular hexagon, and connect the anode to the lower end through the wire 12 to energize it; thereby creating an electric field force from bottom to top inside the steel sheet 2 of the permeable concrete pile. Due to the principle of electroosmosis, the vertical drainage speed of the permeable concrete pile is accelerated, and the permeable concrete pile is used as a vertical drainage channel to drain water to the ground.

[0059] Step 5: Use a water suction device to pump the water that has been drained onto the ground away;

[0060] Step 6, repeat steps 3 to 5 several times;

[0061] Step 7: Using the permeable concrete pile at the center of the original permeable group's hexagon as the target, select the permeable concrete pile to the upper right of the original permeable group's center hexagon as the new permeable group's center hexagon, thus completing the reselection of the permeable group; see attached document for reference. Figure 8 This avoids drainage blind spots caused by a single power supply mode.

[0062] Step 8: Repeat steps 3 to 7 until the soil consolidation degree meets the requirements, then stop the power supply.

[0063] In this process, step 3 lasts for 2 hours, and step 4 lasts for 1 hour. The time ratio of steps 3 to 4 can be 2:1, and the overall time can be extended as needed, ranging from 1 to 4 hours. Considering factors such as electroosmosis energy consumption and electrode corrosion, the required potential gradient is 1.25 V / cm. Steps 3 and 4, being intermittent energization, can slow down electrode corrosion, improve electroosmosis efficiency, and result in superior drainage volume and shear strength compared to conventional electroosmosis.

[0064] Step 5 includes: installing a drainage pipe 5 at the upper end of each permeable concrete pile, and connecting a water pump 4 through the drainage pipe 5 to pump the water discharged to the ground away through the water pump 4.

[0065] In step 6, steps 3 through 5 are repeated six times. This ensures drainage efficiency and effectiveness.

[0066] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A method for manufacturing permeable concrete piles, characterized in that, Includes the following steps: Step 1: Prefabricated sleeve (1) and steel sheet (2). The outer wall of the sleeve wall (15) of the sleeve (1) is provided with a cylindrical spiral groove (13). The steel sheet (2) is screwed into the groove (13) from bottom to top, and a wire (12) is set. Step 2: The assembled casing (1) and steel sheet (2) are lowered to the specified depth by hammer driving or vibratory driving. Step 3: Pour permeable concrete through the feed port (11) until the mixture in the casing (1) meets the design requirements of the pile body; Step 4: Use the rotating pile pulling device (3) to hold the top of the casing (1) and start the motor. The casing (1) is left to vibrate in place for 10 seconds. Then, while vibrating, use the rotating pipe pulling device to pull the casing (1) upward counterclockwise, leaving the steel sheet (2) in place. Step 5: The casing (1) is completely pulled out, completing the pouring of a single permeable concrete pile for combined electro-osmotic drainage.

2. The method for manufacturing a permeable concrete pile according to claim 1, characterized in that: The speed of rotating the tube is controlled at 2.2~2.5m / min.

3. A method for using a permeable concrete pile manufactured according to claim 1, characterized in that, Includes the following steps: Step 1: When making permeable concrete piles, six permeable concrete piles are arranged around each permeable concrete pile in the same regular hexagonal ring at equal intervals. Step 2: Select seven permeable concrete piles in a regular hexagon as a permeable group, so that the permeable concrete piles form a structure in which multiple permeable groups are connected. Step 3: Apply negative electricity to the steel sheet (2) of each group of permeable concrete piles located at the center of the regular hexagon, and apply positive electricity to the six permeable concrete piles around it. Step 4: De-energize and connect the cathode to the upper end of the permeable concrete pile located at the center of the regular hexagon, and connect the anode to the lower end through the wire (12) to energize it; Step 5: Use a water suction device to pump the water that has been drained onto the ground away; Step 6, repeat steps 3 to 5 several times; Step 7: Taking the permeable concrete pile at the center of the original permeable group's regular hexagon as the target, take the permeable concrete pile at the upper right of the center of the original permeable group's regular hexagon as the center of the new permeable group's regular hexagon, thus completing the reselection of the permeable group. Step 8: Repeat steps 3 to 7 until the soil consolidation degree meets the requirements, then stop the power supply.

4. The method of using a permeable concrete pile according to claim 3, characterized in that: Step 3 is performed for 2 hours, and step 4 is performed for 1 hour.

5. The method of using a permeable concrete pile according to claim 3, characterized in that, Step 5 includes: setting a drainage pipe (5) at the upper end of each permeable concrete pile, and connecting a water pump (4) through the drainage pipe (5) to pump the water discharged to the ground away through the water pump (4).

6. The method of using a permeable concrete pile according to claim 3, characterized in that: In step 6, steps 3 to 5 are repeated 6 times.

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