CN204475337U - A kind of hole pressure counter-force steel pipe pile pile pulling device - Google Patents

Abstract

The utility model relates to a pile pulling device for pore pressure reaction force steel pipe piles in the field of foundation pit enclosure and pile foundation engineering in the field of geotechnical engineering. The pile pulling device uses the side wall and seal of the steel pipe pile (1). The pile plug (3), the soil body (2) in the steel pipe pile, forms a fluid storage chamber (9) in the steel pipe pile (1), and continuously injects gas or liquid into the fluid storage chamber (9), increasing the fluid The pressure of the gas or liquid in the storage cavity (9) increases the pore water pressure or pore air pressure of the soil body (2) in the steel pipe pile; and transmits it to the sealed pile plug (3), thereby generating pile pulling force or as a pulling force. A part of the pile force is used to pull out the steel pipe pile (1). This device can also be used for the pullout bearing capacity test of the steel pipe pile (1). The pile pullout equipment is small, the cost is low, and it can solve the problem The problem of the influence of the surrounding environment.

Description

A pile pulling device for pore pressure reaction force steel pipe piles

technical field

The invention relates to the field of foundation pit enclosure and pile foundation engineering in the field of geotechnical engineering.

Background technique

The pulling out of steel pipe piles is one of the key technologies in the field of foundation pit enclosure and pile foundation engineering in the field of geotechnical engineering. The pulling out construction of steel pipe piles can realize the recycling and reuse of steel pipe piles, which is beneficial to saving engineering costs, Reducing the consumption of building materials has very important engineering value. At present, the commonly used steel pipe pile extraction methods mainly include static pile extraction method and vibration pile extraction method. The two methods of pile extraction are high in cost and accompanied by soil extraction, which has a certain impact on the surrounding environment. In addition, the current vertical pullout bearing capacity test of steel pipe piles mainly uses the static load test method or the balance method for pile pullout, and the test cost is high. For large-scale steel pipe piles and steel pipe piles used in offshore engineering, the test cost is very expensive.

Utility model content

The first object of the present invention is to provide the first pile pulling method of pore pressure reaction force steel pipe pile, which can fully mobilize the soil inside the pile to provide reaction force during the pile pulling process , and can solve the problem of pile pulling with soil, has little impact on the surrounding environment, uses small machinery, and has low cost of pulling piles.

The first method for extracting steel pipe piles with pore pressure reaction comprises the following steps:

a) Locate the steel pipe pile to be pulled out, and complete the installation of the sealing pile plug on the steel pipe pile;

b) Using the side wall of the steel pipe pile, the sealed pile plug, and the soil inside the steel pipe pile to form a fluid storage cavity in the steel pipe pile;

c) Injecting one or both of gas and liquid into the fluid storage cavity;

d) increasing the pressure of the gas or liquid in the fluid storage cavity by continuously injecting gas or liquid into the fluid storage cavity;

e) increasing the pore water pressure or pore air pressure of the soil in the steel pipe pile;

f) Using the gas or liquid injected into the fluid storage cavity, the pore water pressure or pore air pressure of the soil in the steel pipe pile is transmitted to the sealing pile plug located on the steel pipe pile;

g) Utilize the gas or liquid pressure acting on the sealed pile plug as the pile pulling force or as a part of the pile pulling force to pull out the steel pipe pile.

In the above method for pulling steel pipe piles with pore pressure reaction force, in the above step g), a vibratory hammer can be installed on the top of the steel pipe pile, and the pile pulling resistance can be reduced through the vibration of the vibratory hammer.

In the above method for pulling steel pipe piles with pore pressure reaction force, in the above step g), an uplifting force can be applied to the steel pipe piles to assist the pile pulling construction.

In the above method for pulling steel pipe piles with pore pressure reaction force, in step g) above, while pulling out piles, the surrounding ground of steel pipe piles can be used to provide reaction force to assist in pile pulling construction, and at the same time reduce the size of the steel pipe piles. Pull out piles with soil on the outside.

In the above-mentioned method for pulling steel pipe piles with pore pressure reaction force, in the above step f), the pressure of the gas or liquid in the fluid storage chamber can be increased to the point where the pressure of the gas or liquid can be formed between the side wall of the steel pipe pile and the soil body. A thin layer of air film or water film reduces the pulling force of the steel pipe pile and the influence of the soil on the pile.

The second object of the present invention is to provide a pile pulling device used in the hole pressure reaction force steel pipe pile pulling method. The pile pulling device can quickly and smoothly implement the hole pressure reaction force steel pipe pile pulling method, and can solve the problem of pulling out The problem of piles with soil has little impact on the surrounding environment, the machinery used is small, and the cost of pulling piles is low.

The pile pulling device includes six parts: a sealed pile plug, a steel pipe pile, the soil inside the steel pipe pile, a fluid storage chamber, a fluid delivery pipeline, and a fluid injector. The sealed pile plug is firmly connected to the side wall of the steel pipe pile and can The structure of sealing the inner cavity of the steel pipe pile. The steel pipe pile is a member with a hollow tubular structure located in the rock and soil body. The fluid storage cavity is composed of a sealed pile plug, the side wall of the steel pipe pile, and the soil inside the steel pipe pile. The enclosed space, the fluid delivery pipeline is a tubular structure for injecting gas or liquid into the fluid storage cavity, and the fluid injector is a device for injecting the fluid into the fluid storage cavity through the fluid delivery pipeline after pressurization.

In the above-mentioned pile pulling device, the above-mentioned fluid injector may be one or a combination of an air compressor, a water pump, and an oil pump.

In the above-mentioned pile pulling device, mechanical equipment capable of providing upward pulling force can be added to assist pile pulling.

In the above-mentioned pile pulling device, a vibratory hammer can be installed on the steel pipe pile to reduce pile pulling resistance.

In the above-mentioned pile pulling device, the above-mentioned sealed pile plug is composed of three parts: a baffle plate, a cover plate and a cushion.

In the above-mentioned pile pulling device, a reinforcing bolt for improving the bearing capacity of the sealed pile plug can be installed in the side wall opening of the steel pipe pile.

In the above-mentioned pile pulling device, a connection bolt can be used between the baffle plate and the cover plate.

The third object of the present invention is to provide the second pile pulling method for steel pipe piles with pore pressure reaction force. This pile pulling method can measure the ultimate pull-out bearing capacity of steel pipe piles. Compared with the traditional pull-out pile bearing capacity test method, The test cost is greatly reduced.

The second hole pressure reaction force steel pipe pile pulling method comprises the following steps:

a) Locate the steel pipe pile to be pulled out, and complete the installation of the sealing pile plug on the steel pipe pile;

b) Using the side wall of the steel pipe pile, the sealed pile plug, and the soil inside the steel pipe pile to form a fluid storage cavity in the steel pipe pile;

c) Injecting one or both of gas and liquid into the fluid storage cavity;

d) increasing the pressure of the gas or liquid in the fluid storage cavity by continuously injecting gas or liquid into the fluid storage cavity;

e) increasing the pore water pressure or pore air pressure of the soil in the steel pipe pile;

f) Using the gas or liquid injected into the fluid storage cavity, the pore water pressure or pore air pressure of the soil in the steel pipe pile is transmitted to the sealing pile plug located on the steel pipe pile;

g) Use the gas or liquid pressure acting on the sealed pile plug as the pile pulling force or as a part of the pile pulling force to pull out the pile, and measure the pressure of the gas or liquid in the fluid storage chamber at the same time, and measure the uplift of the steel pipe pile displacement;

h) Repeat step g) until the steel pipe pile reaches uplift failure;

i) record the data recorded in the finishing step g), and convert the pile pulling force according to the pressure;

j) According to the relationship between the pile pullout force and the uplift displacement of the steel pipe pile, calculate the ultimate pullout bearing capacity of the single pile;

In the above-mentioned second pile pulling method for steel pipe piles with pore pressure reaction force, in the above step j), the ultimate equilibrium equation of the uplift pile can be combined to calculate the pulling-out time of the steel pipe pile according to the gas or liquid pressure during the pile pulling process. The radial deformation during the pile process is analyzed, and the ultimate uplift bearing capacity of the single pile is corrected.

In the above-mentioned second pile pulling method for steel pipe piles with pore pressure reaction force, in the above step j), the ultimate pullout bearing capacity of a single pile can be calculated based on the total pile pulling force minus the internal frictional resistance of the steel pipe pile.

In the above-mentioned second pore pressure reaction force steel pipe pile pulling method, in the above step j), when calculating the soil friction resistance inside the steel pipe pile, the pore water pressure or the soil pore water pressure in the steel pipe pile can be ignored Effect of an increase in pore gas pressure on side friction.

The fourth object of the present invention is to provide a pile pulling device used in the two hole pressure reaction force steel pipe pile pulling methods, the pile pulling device can smoothly implement the second hole pressure reaction force steel pipe pile pulling method, and can Measuring the ultimate pull-out capacity of a single pile with low cost and high speed.

The pile pulling device includes eight parts: sealed pile plug, steel pipe pile, soil inside the steel pipe pile, fluid storage chamber, fluid delivery pipeline, fluid injector, pressure measuring instrument, and pile top displacement measuring instrument. The side wall of the steel pipe pile is firmly connected and can seal the structure of the inner cavity of the steel pipe pile. The steel pipe pile is a member with a hollow tubular structure located in the rock and soil body. The space enclosed by the side wall of the steel pipe pile and the soil inside the steel pipe pile. The fluid delivery pipeline is a tubular structure that injects gas or liquid into the fluid storage cavity. The fluid injector is used to inject the fluid into the fluid storage cavity through the fluid delivery pipeline after pressurization. The pile top displacement measuring instrument is an instrument for measuring the displacement change of the steel pipe pile pile top during the pile pulling process, and the pressure measuring instrument is an instrument for measuring the fluid pressure in the fluid storage cavity.

The hole pressure reaction force steel pipe pile pulling method and the pile pulling device of the present invention can fully mobilize the hole pressure reaction force of the soil in the steel pipe pile to provide the pile pulling reaction force, the pile pulling equipment is small, the cost is low, and it can Solve the problem of the impact of pile pulling with soil on the surrounding environment.

Description of drawings

Fig. 1 is a schematic structural view of the pile pulling device structure used in the first embodiment of the present invention and the second embodiment of the used hole pressure reaction force steel pipe pile pulling method;

Fig. 2 is the schematic cross-sectional view of the steel pipe pile used in the first embodiment and the second embodiment of the present invention used in the hole pressure reaction force steel pipe pile pulling method;

Fig. 3 is a kind of sealing stake plug structure structure diagram that the first embodiment of the present invention and the second embodiment are used;

Detailed ways

As an embodiment of the present invention as shown in Fig. 1 and Fig. 2, the main purpose is to introduce the first pile pulling method of pore pressure reaction force steel pipe pile and the working principle and implementation method of the pile pulling device used therein. Firstly, the structure and working principle of the pore pressure reaction force pile pulling device of the present invention will be introduced with reference to FIG. 1 and FIG. 2 . The pile pulling device uses the steel pipe pile (1) as one of the important components of the pile pulling device. During the insertion of the steel pipe pile (1) into the soil, part of the soil will enter into the steel pipe pile to form the inner soil (2) of the steel pipe pile as shown in Figure 1. For example, before the pile is pulled out, the steel pipe pile The soil body (2) in the pile is less, so it can be backfilled to replenish enough, and then the pile can be pulled out. The soil body (2) in the steel pipe pile can also be flowable mud. A sealing pile plug (3) can be arranged on the top of the steel pipe pile (1), and the sealing pile plug (3) can be a steel plate welded or bolted to the top of the steel pipe pile (1), or a stiffening plate can be welded on the steel pipe pile (1) To improve the bearing capacity of the sealing pile plug (3). The sealing pile plug (3) can also be made like this: first, a steel plate with a certain width is firmly connected (as welded) on the inner side of the steel pipe pile (1) as a baffle (4), and the cover slightly smaller than the cross section of the steel pipe pile (1) The plate (5) is placed below or above the baffle (4), so that the cover (5) and the baffle (4) are closely connected, and a cushion ( 6) In order to improve the sealing ability of the joint between the cover plate (5) and the baffle (4), materials such as rubber pads and plastic pads can be used as the cushion (6), and the baffle (4), the cushion (6) Together with the cover plate (5) to form a sealing pile plug (3), in order to improve the connection strength between the baffle plate (4) and the cover plate (5), a connecting bolt ( 7), the baffle (4) is firmly connected with the cover (5) through the connecting bolt (7), after the pile pulling is completed, the cover (5) can be separated from the baffle (4) through the connecting bolt (7). The cushion (6) and cover plate (5) and connecting bolts (7) can be reused. It is also possible to perforate the side wall of the steel pipe pile (1), set a reinforcing bolt (8) passing through the hole above the sealing pile plug (3) or weld a stiffening plate on the side wall of the steel pipe pile to improve the sealing pile plug (3) The connection strength with the steel pipe pile (1). The space formed by the steel pipe pile (1), the soil body inside the steel pipe pile (2) and the sealed pile plug (3) is the fluid storage chamber (9). Fluid delivery pipeline (12) can be installed on the side wall of sealing pile plug (3) or steel pipe pile (1), and fluid delivery pipeline (12) can be the ventilation pipe that is connected with air compressor, also can be with The water pipe or oil pipe connected to the water pump or the oil pump, and the fluid delivery pipeline (12) need to have a certain pressure bearing capacity, and generally the pressure bearing capacity of 0.5～10MPa gets final product. The fluid injector (11) is a device for injecting fluid into the fluid storage cavity (9) through the fluid delivery pipeline (12) after pressurization. Fluid injector (11) can be one or more combination in air compressor, water pump, oil pump, when pile pulling force is bigger, can adopt high-pressure water pump or high-pressure oil pump as fluid injector (11). In the following part of this embodiment, with reference to Fig. 1 and Fig. 2, the pile pulling method of the steel pipe pile with pore pressure reaction force and the working principle of the above-mentioned pile pulling device are introduced. The pile pulling method of the pore pressure reaction force steel pipe pile can be completed according to the following steps: the first step is to locate the steel pipe pile to be pulled out, find the steel pipe pile (1) to be pulled out, and check the soil filling of the steel pipe pile (1) If the soil body is less, the soil body can be backfilled in an appropriate amount, and the situation of the sealed pile plug (3) on the steel pipe pile (1) can be checked. If there is no sealed pile plug (3) to be reinstalled, then the Install the sealing pile plug (3) in the method of the previous section. If prior to this, when the steel pipe pile (1) is inserted for construction, the installation and construction of the sealing pile plug (3) has been partially completed, then the installation and construction of the remaining part of the sealing pile plug (3) is carried out. If before this, sealing pile plug (3) construction is finished, then can directly utilize and get final product. Complete the first step and go to the second step. In the second step, a fluid storage cavity (9) is formed in the steel pipe pile (1) by using the side wall of the steel pipe pile (1), the sealing pile plug (3), and the soil body (2) inside the steel pipe pile (2). The fluid delivery pipeline (12) can be installed with openings on the side wall of the steel pipe pile (1) or the sealed pile plug (3). Complete the second step and go to the third step. In the third step, one or a combination of gas and liquid is injected into the fluid storage chamber (9) through the fluid delivery pipeline (12), and the gas can be the air injected by the air compressor or the The water injected by the water pump may also be the mud injected by the mud pump, or the oil fluid injected by the oil pump. Complete the third step and go to the fourth step. In this step, the pressure of the gas or liquid in the fluid storage chamber (9) is increased by continuously injecting gas or liquid into the fluid storage chamber (9). In this step, after the gas or liquid injected into the fluid storage chamber (9) is full, the pressure of the gas or liquid in the fluid storage chamber (9) will increase rapidly as the amount of gas or liquid injected increases. Complete step four and go to step five. In this step, with the injection of gas or liquid in the fluid storage cavity (9), the pore water pressure or pore air pressure of the soil body (2) in the steel pipe pile will increase, because the time is relatively short, and the gas or liquid Continuous injection, the increased pore water pressure or pore air pressure of the soil (2) in the steel pipe pile can accumulate. Complete step five and go to step six. In this step, the liquid or gas in the fluid storage chamber (9) is filled, and the gas or liquid injected into the fluid storage chamber (9) can be used as a force transmission medium to move the soil (2) in the steel pipe pile The pore water pressure or pore air pressure is transmitted to the sealing pile plug (3) located on the upper part of the steel pipe pile (1). Complete step six and go to step seven. In this step, since the sealing pile plug (3) has a certain area, the product of the pressure acting on the sealing pile plug (3) is the force acting on the sealing pile plug (3). The direction of this force is in the same direction as the pull-out direction of the steel pipe pile (1), so the gas or liquid pressure acting on the sealed pile plug (3) can be used as the pile pulling force or as a part of the pile pulling force to pull out the steel pipe pile. Pile (1) pulls out construction. The larger the diameter of the steel pipe pile (1), the larger the pore pressure reaction force. In this step, a vibrating hammer (14) can be installed on the top of the steel pipe pile (1), and the pile pulling resistance can be reduced through the vibration of the vibrating hammer (14). Under the situation that vibration hammer (14) is installed, it is more appropriate to adopt gas pressurization. Because the compressibility of the gas is better, the vibration energy of the vibratory hammer (14) can be used for pile extraction with high efficiency. In this step, it is also possible to apply an uplifting force on the steel pipe pile (1) to assist the pile pulling construction, such as laying a crane (13), which can provide part of the pile pulling force during the pile pulling process on the one hand, and on the other hand After the steel pipe pile (1) is pulled out, the stability of the steel pipe pile (1) is maintained, and the steel pipe pile (1) can be properly placed or transported in time. In this step, while the pile is being pulled out, the surrounding ground of the steel pipe pile (1) can be used to provide a reaction force to assist the pile pulling construction, and at the same time, the soil on the outside of the steel pipe pile (1) can be reduced. In the present invention, the greatest advantage of adopting the reaction force produced by the pore water pressure or pore air pressure of the soil body (2) in the steel pipe pile as the pile pulling force is that, during the pile pulling process, the soil body (2) in the steel pipe pile ) and the side wall of the steel pipe pile (1) basically does not increase. Although the compressive stress on the side wall of the steel pipe pile (1) increases, it is mainly fluid pressure such as water pressure or air pressure. Due to the shear strength of the fluid is zero, so the accumulated fluid pressure will not increase the frictional resistance between the soil body (2) in the steel pipe pile and the side wall of the steel pipe pile (1). In addition, the contact surface between the side wall of the steel pipe pile (1) and the soil is a weak link in the strength of the soil. After the air pressure or liquid pressure in the fluid storage chamber (9) reaches a certain level, some gas or liquid will flow along the steel pipe pile. The side wall of the pipe pile (1) overflows. In this case, there will be a water film or an air cushion layer between the soil and the side wall of the steel pipe pile (1), which can achieve the effect of a lubricant and at the same time form a fluid pressure The stress balances the soil pressure around the pile, so that the friction force between the steel pipe pile (1) and the soil is greatly reduced, the difficulty of pulling out the pile is reduced, and the influence of the soil surrounding the steel pipe pile on the surrounding environment can be greatly reduced. On the other hand, due to the fluid pressure inside the steel pipe pile (1) during the pile pulling process, the steel pipe pile (1) expands radially during the pile pulling process, making the soil inside the steel pipe pile (2) The frictional resistance to the steel pipe pile (1) is reduced. The steel pipe pile (1) described in this embodiment is a structure that has a closed cross section and can form a fluid storage chamber (9), including steel pipe piles, structures that include steel pipe pile connections in the continuous wall of steel pipe piles, And other structures in which ancillary components are installed on steel pipe piles (1).

As the second embodiment of the present invention, the main purpose is to introduce the second hole pressure reaction force steel pipe pile pulling method and the working principle and implementation method of the pile pulling device used in conjunction with FIGS. 1 to 3 . This embodiment is very similar to the first embodiment, the difference is that the fluid pressure (i.e. gas or liquid pressure) in the fluid storage chamber (9) and the pile top displacement of the steel pipe pile (1) are measured during the pile pulling process. The content and the method of using these data to calculate the ultimate bearing capacity of single pile uplift. According to the characteristics of the fluid pressure, the fluid pressure in the fluid storage cavity (9) can be calculated by measuring the fluid pressure in the fluid delivery pipeline (12), and a pressure measuring instrument (15) can be installed on the fluid delivery pipeline (12) to calculate the fluid storage. The pressure in chamber (9). It is also possible to directly measure the fluid pressure in the fluid storage cavity. The pile top displacement of the steel pipe pile (1) can be measured by a pile top displacement measuring instrument (16) such as a dial indicator, a displacement sensor or a level. The loading classification and time can be determined according to the current code requirements for relevant pile foundations to carry out the single pile pull-out bearing capacity test, and then according to the current code method, according to the relationship between the pile pull-out force, pile top displacement and time during the pile pull-out process, determine Ultimate pile pulling force. According to the ratio of the internal and external frictional resistance of the steel pipe pile (1) in the pile pulling process of this method, the internal soil frictional resistance of the steel pipe pile (1) is deducted, and the external frictional resistance of the steel pipe pile (1) is calculated, which is the pullout resistance of the single pile. ultimate carrying capacity. The influence of factors such as pile length, pile diameter, and wall thickness on the ultimate uplift bearing capacity of a single pile can also be calculated and analyzed by using the ultimate equilibrium equation of the uplift pile, and can be corrected.

This patent includes but is not limited to other construction methods that can be used by professionals in this field.

Claims (8)

1. a hole pressure counter-force steel pipe pile pile pulling device, it is characterized in that comprising sealing stake plug (3), steel pipe pile (1), the soil body (2) in steel pipe pile, fluid storage chamber (9), fluid-transporting tubing (12), fluid injector (11) six part, wherein sealing stake plug (3) is firmly to be connected with the sidewall of steel pipe pile (1) and can the structure of shutoff steel pipe pile (1) internal cavity, steel pipe pile (1) is for being arranged in the component of Rock And Soil with hollow tubular structure, fluid storage chamber (9) is by sealing stake plug (3), the sidewall of steel pipe pile (1), the space that in steel pipe pile, the soil body (2) encloses, fluid-transporting tubing (12) is tubular structure gas or liquid being injected fluid storage chamber (9), fluid injector (11) is the utensil by being injected fluid storage chamber (9) after pressurized with fluid by fluid-transporting tubing (12).

2. pile pulling device according to claim 1, is characterized in that above-mentioned fluid injector (11) is the one or more combination in air compressor, water pump, oil pump.

3. pile pulling device according to claim 1, it is characterized in that increasing to provide the plant equipment of uplift force to assist pile pulling.

4. pile pulling device according to claim 2, is characterized in that installing on steel pipe pile reducing pile extraction resistance vibrating hammer (14).

5. pile pulling device according to claim 1, is characterized in that above-mentioned sealing stake plug (3) is made up of baffle plate (4), cover plate (5), cushion (6) three part.

6. pile pulling device according to claim 1, is characterized in that installing for improving the reinforcement bolt (8) sealing stake plug (3) supporting capacity at the side-wall hole of steel pipe pile (1).

7. pile pulling device according to claim 1, is characterized in that being connected with connecting bolt (7) between baffle plate (4) with cover plate (5).

8. a hole pressure counter-force steel pipe pile pile pulling device, it is characterized in that comprising sealing stake plug (3), steel pipe pile (1), the soil body (2) in steel pipe pile, fluid storage chamber (9), fluid-transporting tubing (12), fluid injector (11), pressure measuring set (15), displacement at pile top measuring instrument (16) eight part, wherein sealing stake plug (3) is firmly to be connected with the sidewall of steel pipe pile (1) and can the structure of shutoff steel pipe pile (1) internal cavity, steel pipe pile (1) is for being arranged in the component of Rock And Soil with hollow tubular structure, fluid storage chamber (9) is by sealing stake plug (3), the sidewall of steel pipe pile (1), the space that in steel pipe pile, the soil body (2) encloses, fluid-transporting tubing (12) is tubular structure gas or liquid being injected fluid storage chamber (9), fluid injector (11) is the utensil by being injected fluid storage chamber (9) after pressurized with fluid by fluid-transporting tubing (12), displacement at pile top measuring instrument (16) is the instrument measuring steel pipe pile (1) displacement at pile top change in pile pulling process, pressure measuring set (15) is the instrument measuring fluid storage chamber (9) inner fluid pressure.