Force conversion device, cast-in-place pile structure with force conversion device and construction method

Abstract

The invention discloses a force conversion device, a cast-in-place pile structure with the force conversion device and a construction method. The force conversion device comprises an outer side interlayer stiffening pipe, an inner side interlayer stiffening pipe and a flexible communicating vessel. The outer side interlayer stiffening pipe is arranged on the periphery of the inner side interlayer stiffening pipe in a sleeving mode, and the bottom of the inner side interlayer stiffening pipe and the bottom of the outer side interlayer stiffening pipe are connected with the flexible communicating vessels. The invention discloses a cast-in-place pile structure with a force conversion device. The outer side wall of a cast-in-place pile is sleeved with the force conversion device. The construction method of the cast-in-place pile structure with the force conversion device comprises the steps that a hole is formed in a pile, and the total thickness of a soil layer capable of generating negative friction resistance on the formed pile side is obtained; and then a force conversion device is manufactured on site, the force conversion device is fixed to a reinforcement cage and then sinks into a pile hole, and then follow-up work is completed according to a conventional pile forming procedure. Compared with the prior art, the device has the beneficial effects that the negative frictional resistance of the soil layer borne by the pile side of the cast-in-place concrete pile is converted through a specific device, and the unfavorable negative frictional resistance is converted into the favorable positive frictional resistance.

Description

Technical Field

[0001] The invention relates to the field of pile foundations, in particular to a force conversion device and a cast-in-place pile structure and a construction method with the device. Background Art

[0002] Negative friction is the downward friction generated when the settlement of the soil around the pile is greater than the settlement of the pile body. It is common in soft soil, loess and other areas and poses great hazards: 1. The stress on the pile body deteriorates; 2. It leads to structural safety risks.

[0003] There are currently several solutions to the above negative friction problem in engineering: 1. Design refinement. Increase the length of the pile so that the pile end penetrates into the stable stratum. 2. Material and structural measures. Apply anti-friction coatings such as asphalt and polyethylene on the pile side; set up isolation sleeves such as steel or PVC sleeves in the easily subsiding soil layer to cut off the transmission of negative friction. 3. Foundation treatment.

[0004] The above-mentioned solution 1 for the negative friction on the pile side increases the engineering investment, but the negative friction on the pile side does not change; the friction reduction measures added in solution 2 reduce the negative friction on the pile side, but it has not yet been reduced to zero; solution 3 improves or changes the soil layer that causes the negative friction. The negative friction on the pile side depends on the specific foundation treatment measures. The actual engineering geological conditions are ever-changing and cannot be completely solved by this method, and the cost is huge. Summary of the invention

[0005] The purpose of the present invention is to provide a force conversion device and a cast-in-place pile structure and construction method with the device, which converts the adverse effect (negative friction resistance) of the soil layer on the pile side of the concrete cast-in-place pile through a specific device, thereby converting the adverse effect into a favorable effect (positive friction resistance).

[0006] The present invention is implemented through the following technical scheme: a force conversion device, including an outer interlayer stiffening tube 31, an inner interlayer stiffening tube 32 and a flexible communicating vessel 33; wherein the inner interlayer stiffening tube 32 is sleeved on the outer wall of the pile structure and is fixedly connected to the pile structure; the outer interlayer stiffening tube 31 is sleeved on the outer periphery of the inner interlayer stiffening tube 32, and a flexible communicating vessel 33 is connected at the bottom of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31 to connect the inner cavity of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31, and liquid 4 is provided in the inner interlayer stiffening tube 32, the outer interlayer stiffening tube 31 and the flexible communicating vessel 33, and the tops of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31 are both blocked;

[0007] The outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 both include an outer tube body and an inner tube body, the outer tube body is sleeved on the outer periphery of the inner tube body and there is a gap between the inner tube body and the outer tube body, and the outer tube body and the inner tube body are connected by a plurality of vertically distributed stiffening plates 35;

[0008] A plurality of wing plates 34 distributed from top to bottom and extending outward are provided on the outer wall surface of the outer sandwich stiffening tube 31 .

[0009] A cast-in-place pile structure with a force conversion device, the main body is a cast-in-place pile 2, the outer wall of the cast-in-place pile 2 is sleeved with a force conversion device 3; the force conversion device 3 mainly comprises an outer interlayer stiffening tube 31, an inner interlayer stiffening tube 32 and a flexible communicating vessel 33; wherein the inner interlayer stiffening tube 32 is sleeved on the outer wall of the cast-in-place pile 2 and is fixedly connected to the cast-in-place pile 2; the outer interlayer stiffening tube 31 is sleeved on the outer periphery of the inner interlayer stiffening tube 32, and the inner tube 32 and the flexible communicating vessel 33 that connect the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31 are connected at the bottom of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31, and liquid 4 is provided in the inner interlayer stiffening tube 32, the outer interlayer stiffening tube 31 and the flexible communicating vessel 33, and the tops of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31 are both blocked;

[0010] The outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 both include an outer tube body and an inner tube body, the outer tube body is sleeved on the outer periphery of the inner tube body and there is a gap between the inner tube body and the outer tube body, and the outer tube body and the inner tube body are connected by a plurality of vertically distributed stiffening plates 35;

[0011] A plurality of wing plates 34 distributed from top to bottom and extending outward are provided on the outer wall surface of the outer interlayer stiffening tube 31 , and the wing plates 34 extend to the surrounding soil layer.

[0012] A construction method of a cast-in-place pile structure with a force conversion device, characterized in that it comprises the following steps:

[0013] Step 1: Complete the drilling of reinforced concrete piles according to the construction process required by the design, and simultaneously grasp the soil layer distribution at each pile position during the drilling process;

[0014] Step 2: Calculate the total thickness of the soil layer that will produce negative friction on the pile side;

[0015] Step 3: Make a force conversion device 3 at the construction site, the length of the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 of which corresponds to the total thickness of the negative friction resistance soil layer in step 2; then connect the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 at the bottom through the flexible connecting vessel 33 to form the force conversion device 3 as a whole; after water is injected into the outer interlayer stiffening tube 31 or the inner interlayer stiffening tube 32 in the force conversion device 3, the tops of the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 are welded and sealed respectively; then, the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 are temporarily tied together as a whole by iron wire;

[0016] Step 4: Welding connecting plates 6 to the top and bottom of the inner wall of the inner sandwich reinforcing tube 32, the connecting plates are symmetrically arranged to the pile body, and the connecting plates 6 are fixed to the steel cage 21 through the fixing parts 5, wherein there is a gap between the top of the outer tube 31 and the pile foundation cap 1 at the top of the cast-in-place pile 2;

[0017] Step 5: sink the steel cage 21 welded with the force conversion device 3 into the pile hole, and then complete the subsequent work according to the conventional pile-making procedure;

[0018] Step 6: Repeat steps 2-5 until the construction of cast-in-place piles 2 in all areas is completed. When the process of cutting the pile heads is completed, the wire tied in step 3 is cut simultaneously.

[0019] Compared with the previous technology, the beneficial effects of the present invention are:

[0020] 1. The present invention utilizes the principle of communicating vessels to convert negative frictional resistance into positive frictional resistance, thereby achieving the purpose of converting unfavorable factors into favorable factors and effectively improving the bearing capacity of the bored piles; 2. Each structure of the force conversion device can be manufactured in a factory and assembled and constructed on site, which is simple and easy; 3. It completely changes the situation in which traditional designs must take various measures to overcome the adverse effects of negative frictional resistance, resulting in high investment, effectively reduces engineering costs, and has significant social and economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a longitudinal section view of a concrete cast-in-place pile and a conversion device of the present invention;

[0022] Figure 2 for Figure 1 Sectional view at AA in the middle;

[0023] Figure 3 for Figure 1 A detailed partial view of point B in the middle.

[0024] Explanation of reference numbers: 1. Capping platform; 2. Cast-in-place pile; 21. Steel cage; 3. Force conversion device; 31. Outer interlayer stiffening pipe; 32. Inner interlayer stiffening pipe; 33. Flexible connecting vessel; 34. Wing plate; 35. Stiffening plate; 4. Liquid; 5. Fixing part; 6. Connecting plate. DETAILED DESCRIPTION

[0025] The present invention is described in detail below in conjunction with the accompanying drawings:

[0026] like Figure 1-3As shown: a force conversion device, comprising an outer interlayer stiffening tube 31, an inner interlayer stiffening tube 32 and a flexible communicating vessel 33; wherein the inner interlayer stiffening tube 32 is sleeved on the outer wall of the pile structure and is fixedly connected to the pile structure; the outer interlayer stiffening tube 31 is sleeved on the outer periphery of the inner interlayer stiffening tube 32, and a flexible communicating vessel 33 is connected at the bottom of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31 to connect the inner cavity of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31, and liquid 4 is provided in the inner interlayer stiffening tube 32, the outer interlayer stiffening tube 31 and the flexible communicating vessel 33, and the tops of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31 are both blocked;

[0027] The outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 both include an outer tube body and an inner tube body, the outer tube body is sleeved on the outer periphery of the inner tube body and there is a gap between the inner tube body and the outer tube body, and the outer tube body and the inner tube body are connected by a plurality of vertically distributed stiffening plates 35;

[0028] A plurality of wing plates 34 distributed from top to bottom and extending outward are provided on the outer wall surface of the outer sandwich stiffening tube 31 .

[0029] The entire force conversion device can be understood as a U-shaped communicating vessel. When the port of the communicating vessel is blocked, the vertical pipe on one side moves downward, and the liquid inside it will also move downward. Correspondingly, the liquid in the vertical pipe on the other side will move upward, thereby driving the vertical pipe on the other side to move upward.

[0030] The inner wall surface of the outer interlayer stiffening tube 31 and the outer wall surface of the inner interlayer stiffening tube 32 are both smooth surfaces, and the outer wall surface of the outer interlayer stiffening tube 31 is subjected to anti-corrosion treatment.

[0031] The extended length of the wing plate 34 is in the range of 5-15 cm, and the distance between any two adjacent wing plates 34 is twice the extended length of the wing plate 34 .

[0032] The liquid is water, which has a high cost-effectiveness ratio. Oil can also be used to prevent the force conversion device from rusting.

[0033] A cast-in-place pile structure with a force conversion device, the main body is a cast-in-place pile 2, the outer wall of the cast-in-place pile 2 is sleeved with a force conversion device 3; the force conversion device 3 mainly comprises an outer interlayer stiffening tube 31, an inner interlayer stiffening tube 32 and a flexible communicating vessel 33; wherein the inner interlayer stiffening tube 32 is sleeved on the outer wall of the cast-in-place pile 2 and is fixedly connected to the cast-in-place pile 2; the outer interlayer stiffening tube 31 is sleeved on the outer periphery of the inner interlayer stiffening tube 32, and the inner tube 32 and the flexible communicating vessel 33 that connect the inner interlayer stiffening tube 31 and the outer interlayer stiffening tube 31 are connected at the bottom of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31, and liquid 4 is provided in the inner interlayer stiffening tube 32, the outer interlayer stiffening tube 31 and the flexible communicating vessel 33, and the tops of the inner interlayer stiffening tube 32 and the outer interlayer stiffening tube 31 are both blocked;

[0034] The outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 both include an outer tube body and an inner tube body, the outer tube body is sleeved on the outer periphery of the inner tube body and there is a gap between the inner tube body and the outer tube body, and the outer tube body and the inner tube body are connected by a plurality of vertically distributed stiffening plates 35;

[0035] A plurality of wing plates 34 distributed from top to bottom and extending outward are provided on the outer wall surface of the outer interlayer stiffening tube 31 , and the wing plates 34 extend to the surrounding soil layer.

[0036] The cast-in-place pile 2 includes a steel cage 21, on which two groups of upper and lower fixing members 5 are connected, each of which is fixed with a connecting plate 6, and the top and bottom of the inner wall of the inner sandwich stiffening tube 32 are fixedly connected to the corresponding connecting plates 6 respectively.

[0037] Here, the bored pile 2 needs to be cast in situ concrete, so the force conversion device 3 is not directly fixed to the bored pile 3, but first fixed to the steel cage 21 of the bored pile 2. Here, a plurality of wing plates 34 distributed from top to bottom and extending outward are provided on the outer wall of the outer interlayer stiffening tube 31, so that the outer interlayer stiffening tube 31 can be connected to the negative friction resistance soil layer to form a whole, so that when the negative friction resistance soil layer sinks, it can drive the outer interlayer stiffening tube 31 to sink; because the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 are connected at the bottom by a flexible connecting vessel 33, the compensation of the internal liquid can ensure that the inner interlayer stiffening tube 32 is subjected to the upward force generated by the liquid in the tube, thereby realizing the conversion of negative friction resistance to positive friction resistance.

[0038] The flexible communicating vessel 33 is essentially a U-shaped communicating vessel, which allows the bottom of the outer sandwich stiffening pipe 31 to communicate with the bottom of the inner sandwich stiffening pipe 32. The communicating vessel 33 is made of flexible material so as not to prevent the outer sandwich stiffening pipe 31 from sinking with the soil around the pile. The material can be a stainless steel hose or an engineering plastic hose.

[0039] Specifically, when the outer interlayer stiffening tube 31 sinks, the water inside it will sink accordingly. Since the outer interlayer stiffening tube 31 and the bottom of the inner interlayer stiffening tube 32 are interconnected, the water in the inner interlayer stiffening tube 32 will rise accordingly, thereby causing the inner interlayer stiffening tube 32 to have an upward movement tendency, forming a positive friction resistance.

[0040] The inner wall surface of the outer interlayer stiffening tube 31 and the outer wall surface of the inner interlayer stiffening tube 32 are both smooth surfaces, and the outer wall surface of the outer interlayer stiffening tube 31 is treated with anti-corrosion. Since the outer interlayer stiffening tube 31 needs to contact the soil layer, in order to avoid rust and corrosion, the material needs to be treated with anti-corrosion.

[0041] The extension length of the wing plate 34 is in the range of 5-15 cm, and the distance between any two adjacent wing plates 34 is twice the extension length of the wing plate 34. It is ensured that the outer sandwich stiffening pipe can be reliably connected to the negative friction resistance soil layer, and that the negative friction resistance soil layer can drive the outer sandwich stiffening pipe 31 to sink, and correspondingly make the inner sandwich stiffening pipe 32 form positive friction resistance upward.

[0042] The liquid is water, which has a high cost performance ratio, and oil can also be used to prevent the force conversion device from rusting.

[0043] Considering that the bored piles are cast on site, it is necessary to consider the combination of the bored piles and the force conversion device 3. The specific construction method is as follows:

[0044] A construction method for a cast-in-place pile structure for converting negative frictional resistance into positive frictional resistance comprises the following steps:

[0045] Step 1: Complete the drilling of reinforced concrete piles according to the construction process required by the design, and simultaneously grasp the soil layer distribution at each pile position during the drilling process;

[0046] Step 2: Calculate the total thickness of the soil layer that will produce negative friction on the pile side;

[0047] Step 3: Make a force conversion device 3 at the construction site, the length of the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 of which corresponds to the total thickness of the negative friction resistance soil layer in step 2; then connect the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 at the bottom through the flexible connecting vessel 33 to form the force conversion device 3 as a whole; after water is injected into the outer interlayer stiffening tube 31 or the inner interlayer stiffening tube 32 in the force conversion device 3, the tops of the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 are welded and sealed respectively; then, the outer interlayer stiffening tube 31 and the inner interlayer stiffening tube 32 are temporarily tied together as a whole by iron wire;

[0048] Step 4: Welding connecting plates 6 to the top and bottom of the inner wall of the inner sandwich reinforcing tube 32, the connecting plates are symmetrically arranged to the pile body, and the connecting plates 6 are fixed to the steel cage 21 through the fixing parts 5, wherein there is a gap between the top of the outer tube 31 and the pile foundation cap 1 at the top of the cast-in-place pile 2;

[0049] Step 5: sink the steel cage 21 welded with the force conversion device 3 into the pile hole, and then complete the subsequent work according to the conventional pile-making procedure;

[0050] Step 6: Repeat steps 2-5 until the construction of cast-in-place piles 2 in all areas is completed. When the process of cutting the pile heads is completed, the wire tied in step 3 is cut simultaneously.

[0051] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A force conversion device, characterized in that: The invention comprises an outer interlayer stiffening tube (31), an inner interlayer stiffening tube (32) and a flexible communicating tube (33); wherein the inner interlayer stiffening tube (32) is sleeved on the outer wall surface of the pile structure and is fixedly connected to the pile structure; the outer interlayer stiffening tube (31) is sleeved on the outer periphery of the inner interlayer stiffening tube (32); the bottoms of the inner interlayer stiffening tube (32) and the outer interlayer stiffening tube (31) are connected with a flexible communicating tube (33) for communicating the inner cavities of the inner interlayer stiffening tube (32) and the outer interlayer stiffening tube (31); liquid (4) is provided in the inner interlayer stiffening tube (32), the outer interlayer stiffening tube (31) and the flexible communicating tube (33); and the tops of the inner interlayer stiffening tube (32) and the outer interlayer stiffening tube (31) are both sealed; The outer interlayer stiffening tube (31) and the inner interlayer stiffening tube (32) both comprise an outer tube body and an inner tube body, the outer tube body is sleeved on the circumference of the inner tube body and a gap exists between the inner tube body and the outer tube body, and the outer tube body and the inner tube body are connected via a plurality of vertically distributed stiffening plates (35); A plurality of wing plates (34) distributed from top to bottom and extending outwards are provided on the outer wall surface of the outer sandwich stiffening tube (31).

2. A force conversion device according to claim 1, characterized in that: The inner wall surface of the outer interlayer stiffening tube (31) and the outer wall surface of the inner interlayer stiffening tube (32) are both smooth surfaces, and the outer wall surface of the outer interlayer stiffening tube (31) is subjected to anti-corrosion treatment.

3. A force conversion device according to claim 1, characterized in that: The outward extension length of the wing plate (34) is in the range of 5-15 cm, and the distance between any two vertically adjacent wing plates (34) is twice the outward extension length of the wing plate (34).

4. A force conversion device according to claim 1, characterized in that: The liquid is water.

5. A cast-in-place pile structure with a force conversion device, characterized in that: The main body is a cast-in-place pile (2), and the outer wall of the cast-in-place pile (2) is sleeved with a force conversion device (3); the force conversion device (3) mainly comprises an outer sandwich stiffening pipe (31), an inner sandwich stiffening pipe (32) and a flexible communicating vessel (33); wherein the inner sandwich stiffening pipe (32) is sleeved on the outer wall of the cast-in-place pile (2) and is fixedly connected to the cast-in-place pile (2); the outer sandwich stiffening pipe (31) is sleeved on the outer wall of the inner sandwich stiffening pipe (32); A flexible communicating vessel (33) is connected at the bottom of the inner interlayer stiffening tube (32) and the outer interlayer stiffening tube (31) to communicate the inner cavities of the inner interlayer stiffening tube (32) and the outer interlayer stiffening tube (31); a liquid (4) is provided in the inner interlayer stiffening tube (32), the outer interlayer stiffening tube (31) and the flexible communicating vessel (33); and the tops of the inner interlayer stiffening tube (32) and the outer interlayer stiffening tube (31) are both blocked; The outer interlayer stiffening tube (31) and the inner interlayer stiffening tube (32) both comprise an outer tube body and an inner tube body, the outer tube body is sleeved on the circumference of the inner tube body and a gap exists between the inner tube body and the outer tube body, and the outer tube body and the inner tube body are connected via a plurality of vertically distributed stiffening plates (35); A plurality of wing plates (34) distributed from top to bottom and extending outward are provided on the outer wall surface of the outer sandwich stiffening tube (31), and the wing plates (34) extend to the surrounding soil layer.

6. A cast-in-place pile structure with a force conversion device according to claim 5, characterized in that: The cast-in-place pile (2) includes a steel cage (21) provided therein, two sets of upper and lower fixing members (5) being fixedly connected to the steel cage (21), the two sets of fixing members (5) each being fixed with a connecting plate (6), and the top and bottom of the inner wall surface of the inner sandwich stiffening tube (32) are respectively fixedly connected to the corresponding connecting plates (6).

7. A cast-in-place pile structure with a force conversion device according to claim 5, characterized in that: The inner wall surface of the outer interlayer stiffening tube (31) and the outer wall surface of the inner interlayer stiffening tube (32) are both smooth surfaces, and the outer wall surface of the outer interlayer stiffening tube (31) is subjected to anti-corrosion treatment.

8. A cast-in-place pile structure with a force conversion device according to claim 5, characterized in that: The outward extension length of the wing plate (34) is in the range of 5-15 cm, and the distance between any two vertically adjacent wing plates (34) is twice the outward extension length of the wing plate (34).

9. A cast-in-place pile structure with a force conversion device according to claim 5, characterized in that: The liquid is water.

10. A construction method of a cast-in-place pile structure with a force conversion device, characterized in that: The following steps are involved: Step 1: Complete the drilling of reinforced concrete piles according to the construction process required by the design, and simultaneously grasp the soil layer distribution at each pile position during the drilling process; Step 2: Calculate the total thickness of the soil layer that will produce negative friction on the pile side; Step 3: manufacturing a force conversion device (3) at a construction site, wherein the lengths of the outer interlayer stiffening tube (31) and the inner interlayer stiffening tube (32) thereof correspond to the total thickness of the negative friction resistance soil layer in step (2); then, the outer interlayer stiffening tube (31) and the inner interlayer stiffening tube (32) are connected at the bottom by a flexible connecting vessel (33) to form the force conversion device (3) as a whole; after water is injected into the outer interlayer stiffening tube (31) or the inner interlayer stiffening tube (32) in the force conversion device (3), the tops of the outer interlayer stiffening tube (31) and the inner interlayer stiffening tube (32) are welded and sealed respectively; and then, the outer interlayer stiffening tube (31) and the inner interlayer stiffening tube (32) are temporarily tied together as a whole by iron wire; Step 4: Connecting plates (6) are welded to the top and bottom of the inner wall of the inner sandwich reinforcing tube (32), respectively. The connecting plates are arranged symmetrically with the pile body, and the connecting plates (6) are fixed to the steel cage (21) through fixing members (5), wherein a gap exists between the top of the outer tube (31) and the pile foundation cap (1) at the top of the cast-in-place pile (2); Step 5: sink the steel cage (21) welded with the force conversion device (3) into the pile hole, and then complete the subsequent work according to the conventional pile-making procedure; Step 6: Repeat steps 2-5 until the construction of cast-in-place piles (2) in all areas is completed. When the process of cutting the pile heads is completed, the wire tied in step 3 is cut simultaneously.

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