CN211285602U

CN211285602U - Concrete pipe pile offshore pile sinking construction system

Info

Publication number: CN211285602U
Application number: CN201921807280.1U
Authority: CN
Inventors: 刁钰; 朱鹏宇; 郑刚
Original assignee: Tianjin University
Current assignee: Tianjin University
Priority date: 2019-10-25
Filing date: 2019-10-25
Publication date: 2020-08-18
Anticipated expiration: 2029-10-25

Abstract

The utility model belongs to the technical field of offshore pile sinking, and discloses a concrete pipe pile offshore pile sinking construction system, which comprises a pile gripper and a grouting rotary spray pipe which are matched for use, wherein the pile gripper is sleeved outside the grouting rotary spray pipe and is arranged coaxially with the grouting rotary spray pipe; the bottom of the grouting rotary spray pipe is provided with a rotary nozzle and a drill bit, and the drill bit is positioned below the rotary nozzle; the pile gripper comprises a plurality of rollers which are uniformly distributed in the radial direction, and the diameters of inscribed circles of the rollers are the same as the outer diameter of the concrete pipe pile; the maximum outer diameters of the drill bit, the rotary nozzle and the grouting rotary nozzle are all smaller than the inner diameter of the concrete pipe pile. The utility model can realize one-time construction of offshore pile sinking, thereby saving construction period; the problem of difficult pile sinking of the concrete tubular pile caused by high frictional resistance of high-stress state sand to the pile wall is effectively solved, the connection strength of the sand and the pile interface is effectively improved, the effective pile diameter of the concrete tubular pile is enlarged, and the bearing capacity is improved.

Description

Concrete pipe pile offshore pile sinking construction system

Technical Field

The utility model belongs to the technical field of marine pile sinking, specific theory relates to a concrete pipe pile marine pile sinking construction system, is particularly suitable for the following dense sand soil environment of sea surface.

Background

When the platform is operated on the sea, the platform foundation needs to be driven into a soil layer below seawater. Compared with land construction, the sea water pressure action exists above the soil layer of the marine pile foundation, so that the compactness of the soil body is higher, and a stronger stress field exists, so that the pile sinking of the marine concrete pipe pile is more difficult. The sandy soil has rough surface, and can generate great friction resistance in the pile sinking process of the precast pile under a high stress field, so that the problem is more obvious in the sandy soil layer. Therefore, the offshore pile foundation generally adopts steel piles, and compared with concrete pipe piles, the offshore pile foundation can reduce pile sinking frictional resistance as much as possible. However, how to finish pile sinking of the concrete pipe pile in the offshore high-stress sandy soil is not well solved, and the stress level of the sandy soil and the friction coefficient between the sandy soil and the pile side should be reduced by successfully finishing pile sinking of the concrete pipe pile in the undersea sandy soil.

The high-pressure rotary spraying method is a foundation treatment method commonly used in onshore construction, and is a chemical reinforcing method which adopts high-pressure cement slurry to form a jet flow by spraying through a nozzle, so as to cut soil and prefabricate and mix the soil with cement reinforcing bodies. The high-pressure rotary spraying technology on land is generally used for reinforcing and treating soft foundation soil.

SUMMERY OF THE UTILITY MODEL

The utility model discloses the technical problem who puts the effort in the foundation soil of solving marine concrete pipe pile below the sea water, pile sinking difficulty in especially the sand provides a concrete pipe pile marine pile sinking construction system, is applied to marine concrete pipe pile construction with high-pressure jet grouting technique, reduces concrete pipe pile's pile sinking injection resistance to realize once only sinking, save the time limit for a project.

In order to solve the technical problem, the utility model discloses a following technical scheme realizes:

a concrete pipe pile offshore pile sinking construction system comprises a pile gripper and a grouting rotary spray pipe which are matched, wherein the pile gripper is sleeved outside the grouting rotary spray pipe and is arranged coaxially with the grouting rotary spray pipe; the bottom of the grouting rotary spray pipe is provided with a rotary nozzle and a drill bit, and the drill bit is positioned below the rotary nozzle.

Further, pile gripper includes the gyro wheel of a plurality of radial equipartitions, and is a plurality of the inscribe circle diameter of gyro wheel is the same with concrete pipe pile's external diameter.

Further, the drill bit, the rotary nozzle and the maximum outer diameter of the grouting rotary nozzle are all smaller than the inner diameter of the concrete pipe pile.

Furthermore, the rotary nozzles are uniformly distributed on the wall surface of the grouting rotary spray pipe in the radial direction.

Further, the surface of the drill bit is provided with a plurality of bulges.

The utility model has the advantages that:

firstly, the high-pressure rotary spraying slurry is sprayed out to treat sandy soil with high stress level and high compactness, so that the original soil body structure is damaged, and a more loose soil body structure is formed; the cement paste and the sandy soil are fully mixed to form cement sandy soil with lower stress level, and the roughness of the surface of sandy soil particles is reduced; after treatment, the filling resistance of the concrete pile during pile sinking is obviously reduced, and the sinking of the concrete pipe pile in a sand soil body in a seawater environment can be smoothly realized.

(two) this utility model can realize the disposable pile sinking of concrete pipe pile marine construction, saves the time limit for a project, has reduced manpower and materials cost.

After the guniting treatment of the utility model is utilized, the sandy soil and the cement grout are mixed into the cement sandy soil, compared with the contact surface of the untreated sandy soil and the pile body, the contact surface of the cement sandy soil and the pile body has obvious improvement on the mechanical connection effect; after the cement sand is cured, the cement sand is effectively connected with the outer wall of the concrete pipe pile, the effective stress range of the concrete pipe pile is enlarged, and the bearing capacity of the concrete pipe pile is obviously improved.

Drawings

Fig. 1 is a schematic structural diagram of a concrete pipe pile offshore pile sinking construction system provided by the present invention;

fig. 2 is a schematic view of a construction operation state of the concrete pipe pile offshore pile sinking construction system provided by the present invention;

fig. 3 is a horizontal sectional view of a concrete pipe pile and cement sand mixed structure.

In the above figures: 1-pile gripper; 2-grouting rotary spray pipe; 3-rotating the nozzle; 4-a drill bit; 5-a roller; 6-concrete pipe pile; 7-cement sand soil.

Detailed Description

In order to further understand the contents, features and effects of the present invention, the following embodiments are illustrated and described in detail with reference to the accompanying drawings:

as shown in fig. 1, the embodiment provides a concrete pipe pile offshore pile sinking construction device, including embracing pile ware 1 and slip casting rotary spraying pipe 2 that the cooperation was used, the outside of slip casting rotary spraying pipe 2 is located to embracing pile ware 1 cover to with slip casting rotary spraying pipe 2 coaxial line setting.

Pile gripper 1 includes a plurality of radial equipartitions and inwardly extending's gyro wheel 5, and a plurality of gyro wheels 5 distribute on same circular on the plane, and the inscribe circle diameter of a plurality of gyro wheels 5 is the same with concrete pipe pile 6's external diameter (diameter). The pile gripper 1 is used for righting the concrete pipe pile 6 on one hand and ensuring that the concrete pipe pile 6 keeps a vertical state in the pile sinking process; on the other hand, the pile gripper 1 slides downwards through a plurality of rollers 5 to realize the downward release of the concrete pipe pile 6.

Grouting rotary spray pipe 8 is made of steel, rotary spray port 3 and drill bit 4 which are integrally connected are arranged at the bottom of the grouting rotary spray pipe, drill bit 4 is located below rotary spray port 3, and the maximum outer diameters of grouting rotary spray pipe 2, rotary spray port 3 and drill bit 4 are all smaller than the inner diameter of concrete pipe pile 6, so that the grouting rotary spray pipe, the rotary spray port 3 and the drill bit can freely move independently of concrete pipe pile 6, and high-pressure rotary spray operation is performed while drilling. The grouting rotary spray pipe 2 not only conveys rotary spraying slurry for the lower rotary spray nozzle 3, but also drives the drill bit 4 to rotate through the rotation of the grouting rotary spray pipe 2, so as to provide torque for the drill bit 3.

Spout 3 is revolved in the slip casting radially evenly distributed on the wall of spout 2 is revolved in the slip casting, and drill bit 4 revolves the bottom of spout 2 through bolt or screw thread fixed connection in the slip casting, or drill bit 4 revolves spout 2 integrated into one piece with the slip casting. The drill bit 4 makes the sandy soil on the lower part of the concrete pipe pile 6 soft by drilling downwards, and reduces the pile end resistance in the pile sinking process. The surface of the drill bit 4 is provided with a plurality of bulges so as to facilitate smooth downward drilling in soil.

The utility model discloses in, utilize high pressure to spout the sandy soil of the high stress state in the technique processing sea water soon, not in order to form high pressure and spout the stake soon, but utilize and spout the method soon and make the sandy soil become soft, reduce the closely knit degree of disposal area sandy soil to make the stake soil contact surface lubricated, pile end resistance and stake side resistance when reducing the pile sinking.

As shown in fig. 2, the utility model discloses a concrete pipe pile marine pile sinking construction equipment, its working process is as follows:

the method comprises the following steps: and (5) positioning the pile sinking position, and vertically placing the grouting rotary spray pipe 2 right above the pile sinking position. And (3) placing the prefabricated concrete pipe pile 6 outside the grouting rotary spray pipe 2 in a sleeving manner, clamping the concrete pipe pile 6 by using the pile gripper 1, and fixing the concrete pipe pile 6 right above the pile sinking position. The axial line of the grouting rotary spray pipe 2 and the axial line of the concrete pipe pile 6 are on the same straight line with the pile sinking position.

The concrete pipe pile 6 is prefabricated before the pile sinking operation of offshore construction, the impervious grade of the cement adopted by the concrete pipe pile 6 is not less than P8, and the concrete grade is determined according to the seawater pressure on the pile top. In addition, the concrete pipe pile 6 can be prefabricated and maintained in advance to form a pile by adopting impervious and corrosion-resistant concrete, concrete maintenance is not needed to be carried out under the sea water, higher pile forming quality is ensured, and adverse effects of various harmful ions in the sea water on the durability of the concrete pipe pile 6 during maintenance of the bored pile in an underwater environment can be avoided.

Step two: and (3) performing drilling and high-pressure rotary spraying operation, drilling while performing rotary spraying in the process of lowering the grouting rotary spray pipe 2, vertically drilling the sand downwards by using a drill bit 4, and simultaneously pumping the prepared high-concentration cement slurry into the grouting rotary spray pipe 2 through a grouting pump to fully stir and mix the prepared high-concentration cement slurry and the sand at the position of the pile to be sunk, so that the sand is changed into a loose state from a high-stress tight state to form cement sand 7 with a lower stress level.

Wherein, the water-cement ratio of the high-concentration cement slurry used for the rotary spraying is not more than 0.4 in consideration of the dilution effect of seawater on the slurry. The pressure value of the grouting pump for high-pressure rotary spraying is determined according to the strength of effective stress in the sandy soil, and generally should not be lower than the water and soil pressure value of the sandy soil below seawater.

The grouting rotary spraying pipe 2 is controlled to rotate and descend, cement slurry is sprayed and stirred from top to bottom in a rotary mode, and the rotary spraying speed can be adjusted and the cement slurry can ascend and descend at any time during the process. Dividing the grouting rotary jet pipe into a plurality of same or different section depths according to the designed elevation, and after the grouting rotary jet pipe 2 descends by one section depth, utilizing the pile gripper 1 to downwards deliver the concrete pipe pile 6 by the same section depth (the pile sinking depth of the concrete pipe pile 6 is not more than the depth of the position of the drill bit 4), and repeating the operation until the concrete pipe pile 6 reaches the designed elevation position.

Step three: and lifting the grouting rotary spraying pipe 2 with the rotary nozzle 3 and the drill bit 4 upwards from the concrete pipe pile 6.

Step four: and standing and curing the cement sand 7 until the strength of the cement sand 7 reaches the requirement.

After standing and curing, as shown in fig. 3, an effective connection with sufficient strength is formed between the cement sand 7 and the concrete pipe pile 6, so that a stressed working whole is formed, and the bearing capacity of the concrete pipe pile 6 is increased.

Although the preferred embodiments of the present invention have been described with reference to the accompanying drawings, the present invention is not limited to the above embodiments, which are only illustrative and not restrictive, and those skilled in the art can make various changes without departing from the spirit and the scope of the invention as claimed.

Claims

1. A concrete pipe pile offshore pile sinking construction system is characterized by comprising a pile gripper and a grouting rotary spray pipe which are matched with each other, wherein the pile gripper is sleeved outside the grouting rotary spray pipe and is arranged coaxially with the grouting rotary spray pipe; the bottom of the grouting rotary spray pipe is provided with a rotary nozzle and a drill bit, and the drill bit is positioned below the rotary nozzle.

2. The concrete pipe pile offshore pile sinking construction system of claim 1, wherein the pile gripper comprises a plurality of radially and uniformly distributed rollers, and the diameters of inscribed circles of the plurality of rollers are the same as the outer diameter of the concrete pipe pile.

3. The system of claim 1, wherein the drill bit, the rotary nozzle and the grouting rotary nozzle are all smaller than the inner diameter of the concrete pipe pile in maximum outer diameter.

4. The concrete pipe pile offshore pile sinking construction system of claim 1, wherein the rotary nozzles are radially and uniformly distributed on the wall surface of the grouting rotary nozzle pipe.

5. The system of claim 1, wherein the drill bit surface is provided with a plurality of protrusions.