CN113915412A

CN113915412A - Biological protection and reinforcement device for marine pipeline and application method thereof

Info

Publication number: CN113915412A
Application number: CN202111514179.9A
Authority: CN
Inventors: 张凤鹏; 陈旭光; 高兴政; 魏佳康
Original assignee: Ocean University of China
Current assignee: Ocean University of China
Priority date: 2021-12-13
Filing date: 2021-12-13
Publication date: 2022-01-11
Anticipated expiration: 2041-12-13
Also published as: CN113915412B

Abstract

The invention discloses a biological protection and reinforcement device for an ocean pipeline and a using method thereof, and belongs to the technical field of ocean pipeline protection. The grouting anchor comprises a fixed cable and a grouting anchor, wherein the fixed cable comprises a biological culture rope and a chain; the grouting anchor is integrally of a flat plate structure and comprises a four-way grouting pipe and an anchor box; the four-way grouting pipe comprises a main grouting pipe and an auxiliary grouting pipe; anchor legs are arranged in the anchor box and slide back and forth in a sliding cavity of the anchor box; a sliding groove is formed in the upper surface of the anchor box; a pin plate is fixed in the middle of the anchor leg and slides back and forth in the sliding groove; and a spring is arranged at the rear end of the anchor leg. The invention can effectively prevent and treat the scouring disaster of the marine pipeline while reinforcing the marine pipeline, and realizes the combination of the pipeline base protection and the aquaculture measures.

Description

Biological protection and reinforcement device for marine pipeline and application method thereof

Technical Field

The invention relates to the technical field of marine pipeline protection, in particular to a biological protection and reinforcement device for a marine pipeline and a use method thereof.

Background

A large number of various resources are stored in the ocean, and the ocean comprises a large number of material resources such as ocean petroleum and natural gas and ocean energy sources such as wave energy, ocean current energy, wind energy and the like. The marine pipeline transportation plays an irreplaceable important role in marine oil and gas exploitation, marine wind power generation, tidal power generation and the like, has the advantages of continuous transportation, large transportation volume, convenient management and the like, is widely applied to marine oil and gas transportation and power transmission, and is known as a marine lifeline. The marine pipeline is usually placed in parallel, semi-buried or fully buried in a seabed, the soil body around the pipeline is subjected to the action of downflow and horseshoe vortex under the action of wave current, particles migrate, scouring pits are formed around the bottom of the pipeline, and the marine pipeline is in long-distance suspension span.

Traditional marine pipeline scour protection methods can be divided into two main categories: active protection and passive protection. The active protection means reduces the energy of wave current scouring around the marine pipeline, reduces the down-flow and horseshoe vortex for scouring the seabed, and realizes the protection of the marine pipeline scouring. The current common marine pipeline erodees initiative safeguard means includes that it is extremely poor in order to guide rivers to set up the guide plate in the pipeline side of meeting a current, cuts down wave current energy, and this kind of means flow direction adaptability because marine environment is complicated, unrestrained flow direction is changeable, leads to it very easily to lose efficacy, and it is big to use the guide plate to carry out the construction degree of difficulty that the pipeline erodeed the protection, and engineering cost is high, can't use widely by a large scale. The passive protection is a protection means for improving the scouring resistance by changing the foundation material at the periphery of the marine pipeline, the traditional passive protection means is mainly stone throwing protection, and stone or sand bags are thrown at the periphery of the pipeline to improve the scouring resistance at the periphery of the pipeline in the stone throwing protection direction.

Aiming at the occurrence of the current instability condition of the marine pipeline, an effective method for scouring protection and instability reinforcement of the marine pipeline needs to be provided urgently. The applicant has found that although patent applications in the prior art propose solutions, they all have drawbacks.

The Chinese invention patent application with the application number of CN201811482395 discloses a seabed bearing mechanism for ocean engineering and a construction method, and the seabed bearing mechanism comprises a supporting substrate, fixing piles are fixedly arranged at the bottom of the supporting substrate, side surrounding plates are fixedly arranged on two sides of the top of the supporting substrate, a water flowing channel is formed between the fixing piles, a groove is formed in the top of each side surrounding plate, a hoisting hanging ring is arranged inside the groove, shock absorbing pads are fixedly arranged on the inner side walls of the side surrounding plates, ocean pipelines are arranged on the inner sides of the two shock absorbing pads, an installation extension plate is arranged at the top of each shock absorbing pad, an installation screw hole is formed in the installation extension plate, and an upper movable plate is arranged at the top of the installation extension plate. The marine pipeline suspension device has the defects that the marine pipeline is used when suspended, the marine pipeline needs to be firstly hoisted for construction, and the difficulty of seabed operation is high.

Chinese patent application No. CN201811482395 discloses an anti-impact vibration marine pipeline protection device, which comprises a pipe foundation, a weight layer, a vibration attenuation ring and an inner coating, wherein the steel concrete member in the weight layer comprises an upper steel concrete and two lower steel concretes, a joint of the upper steel concrete and the lower steel concrete is a bump structure, a bump of the upper steel concrete is arranged below the bump of the lower steel concrete, an outer ring and an inner ring are arranged in the vibration attenuation ring, a spring is arranged in the outer ring, a first damping member is arranged on one side of the inner ring close to the outer ring, a second damping member is arranged on one side of the inner ring close to the pipe foundation, and a roller is arranged between the first damping member and the second damping member. The external impact load and vibration load are resisted through the arranged steel concrete piece and the vibration damping ring, but the problem of instability of the pipeline cannot be solved.

The Chinese patent application with the application number of CN202010740870 discloses an offshore oil gas marine pipeline protection device, which comprises a trapezoidal long frame, bionic aquatic weeds, U-shaped piles, a rolling assembly and a cathode protection assembly, wherein the top of the trapezoidal long frame is fixedly connected with the U-shaped piles through a second cross frame, a pillow plate is arranged in the trapezoidal long frame, a group of guide rails are installed on the pillow plate, an arch-shaped plate is fixedly connected onto the guide rails, the bionic aquatic weeds are installed on a seabed, first cross frames are installed on two sides of each U-shaped pile, and the first cross frames are fixedly connected with two side edges of the arch-shaped plate through damping pieces. The pipeline is fixedly connected with each other through a flexible pipe, a pair of rolling assemblies are arranged in the flexible pipe, each rolling assembly comprises a ball and a sleeve, the sleeves are rotatably connected with the inner cavity of the pipe and the flexible pipe through the balls, and the cathode protection assemblies are fixed in the pipeline through mounting plates. It prevents the washing away effect of rivers to the seabed through the bionical pasture and water that sets up, and the damping piece absorbs vibration and crooked energy, and the spoiler reduces the vibration that the vortex caused, prevents that the pipeline from taking place the drastic change bucking, and rolling assembly carries out corresponding rotation to the thermal effect in the pipeline, reduces the influence that the thermal effect brought, and cathodic protection subassembly is used for protecting the pipeline to resist marine corrosion environment. The disadvantage is that the ball sleeve and the like have complex structures and are easy to damage and difficult to maintain in a long-term seabed environment.

The present application seeks to address the drawbacks of the conventional marine pipeline protection methods in the prior art, and to provide a new solution.

Disclosure of Invention

The invention aims to provide a biological protection and reinforcement device for an ocean pipeline and a using method thereof, which can solve the problems of poor effect, high construction difficulty and high possibility of failure of the traditional ocean pipeline protection scheme.

On one hand, in order to solve the problems in the prior art, the invention provides a biological protection and reinforcement device for an ocean pipeline, which comprises a fixed cable and grouting anchors, wherein the two ends of the fixed cable are respectively connected with the grouting anchors, and the biological protection and reinforcement device is characterized in that:

the fixed cable comprises a biological culture rope and a chain; the chain is connected with the biological growth rope and the grouting anchor;

the grouting anchor is integrally of a flat plate structure and comprises a four-way grouting pipe and an anchor box; the four-way grouting pipe comprises a main grouting pipe and an auxiliary grouting pipe, wherein the main grouting pipe and the auxiliary grouting pipe are arranged in a crossed mode and welded to the upper surface of the anchor box;

and anchor legs are arranged in the anchor box and slide back and forth in the sliding cavity of the anchor box. A sliding groove is formed in the upper surface of the anchor box at a position corresponding to the intersection part of the grouting main pipe and the anchor leg; a pin plate is fixed in the middle of the anchor leg and slides back and forth in the sliding groove; the rear ends of the anchor legs are provided with springs, and the front ends of the anchor legs are sharp parts.

Preferably, the chain, the biological growth rope and the grouting anchor are connected through retaining rings. In order to facilitate replacement and adjustment of the length of the fixing cable, the retaining ring is a movable and detachable retaining ring.

Preferably, the biological culture rope is formed by twisting two strands of rubber strips with the width of 3-10 cm, and fine shellfish seedlings of clustered shellfish can be clamped in a twisted rope seam to provide fine shellfish seeds for later propagation and growth of shellfish.

Preferably, the shellfish is mussel, scallop, oyster or barnacle.

Preferably, the grouting anchorage device and the chain are made of stainless steel materials resisting seawater corrosion, and the surface of the grouting anchorage device and the chain is provided with a biological adhesion preventing coating. Preventing the shellfish on the biological culture rope from spreading and propagating towards the grouting anchorage device and the chain and attenuating the material performance of the shellfish.

Preferably, the cross sections of the main grouting pipe and the auxiliary grouting pipe are semicircular.

On the other hand, in order to solve the problems in the prior art, the invention also provides a using method of the biological protection and reinforcement device for the marine pipeline, which is characterized by comprising the following steps:

A. prefabricating a fixed cable and a grouting anchor with proper sizes, and connecting the fixed cable with the grouting anchor;

B. determining the laying position of the marine pipeline by an underwater positioning technology, and arranging grooves parallel to the pipeline on two sides of the marine pipeline;

C. applying thrust to the anchor legs to further compress the pre-compressed springs, enabling the rigid grouting pipes to respectively penetrate through main grouting pipes on a plurality of grouting anchors arranged at intervals, and tightly clamping the rigid grouting pipes by pin plates; the rigid grouting pipe is connected with the construction ship and used for fixing a grouting anchor and conveying grouting slurry;

D. preliminarily fixing a plurality of anchor boxes connected in series by rigid grouting pipes in a groove on one side of an ocean pipeline;

E. grouting through the rigid grouting pipe, and simultaneously drawing out the rigid grouting pipe from a grouting main pipe of the grouting anchor, wherein the clamping force of the rigid grouting pipe on the pin plate disappears when the rigid grouting pipe is drawn out, and the anchor leg is popped out under the thrust of the spring so as to insert the anchor leg into a seabed; the grouting slurry is consolidated with the seabed, so that the grouting anchor is further fixed in the seabed;

F. the same is done in a groove on the other side of the marine pipeline, with the guy cable pressed against the top area of the marine pipeline.

To prevent the guy wires from shifting, snaps, detents or location pads are provided between the guy wires and the marine pipeline.

Preferably, the grouting slurry is cement-water glass slurry, the ratio of cement to water glass is 1:1, and the slurry can be rapidly solidified under the condition of running water.

Preferably, the distance between adjacent fixed cables is 0.5-3 m, and the design depends on the hydrological conditions at the pipeline to be protected, so that the arrangement is dense due to larger wave flow.

Preferably, adjacent fixing cable is connected through biological growing rope, forms network structure, can further improve whole reinforcement and scour prevention's effect.

The invention has the characteristics and beneficial effects that:

1. the fixing cable can effectively fix the marine pipeline through the inclined pulling structure, so that the marine pipeline is tightly attached to the seabed.

2. The fixed cable comprises a biological growing rope, the energy dissipation and impact reduction effects are achieved through flexible oscillation and water flow decomposition in the early stage, shellfish is propagated in large quantities in the later stage to form a 'biological water retaining wall' with high rigidity, the protection of basic scouring is achieved by weakening the downflow and the horseshoe vortex which scour the seabed, the protection is adaptive to the water flow effect in each direction, when the water flow changes, the energy dissipation and impact reduction effects are guaranteed to be unchanged, and incoming flows in multiple directions are effectively blocked.

3. The invention fully combines the biological culture technology with the grouting anchoring technology, can reinforce the marine pipeline and effectively prevent and treat the scouring disaster of the marine pipeline at the same time, and has strong flow direction adaptability and better active protection effect compared with the traditional sacrificial pile protection; compared with the traditional riprap protection, the invention has strong integrity and long passive protection period. Meanwhile, the invention is based on the marine environment, adopts marine organisms as the protective material, has strong ecological friendliness, can be repeatedly recycled for cultivation, has better economic benefit, and can realize the combination of tube-based protection and aquaculture.

Drawings

FIG. 1 is a schematic view of the overall structure of the present invention;

FIG. 2 is a schematic side view of the overall structure of the present invention;

FIG. 3 is a schematic view of a biological growing rope structure;

FIG. 4 is a schematic view of an overall grouting anchor structure;

FIG. 5 is a schematic view of a grouting anchor with springs in a compressed state;

FIG. 6 is a schematic view of a grouting anchor with a spring in an elastically-opened state;

FIG. 7 is a schematic structural view of an anchor box portion of a grouting anchor;

FIG. 8 is a schematic view of the anchor leg and pin plate configuration;

fig. 9 is a schematic view of the structure of an anchor box and a four-way grouting pipe in a grouting anchor.

List of reference numerals: 1. a fixed cable; 2. an offshore pipeline; 3. grouting an anchorage device; 4. a seabed; 5. biologically growing the rope; 6. shellfish; 7. a chain; 8. grouting a main pipe; 9. grouting an auxiliary pipe; 10. a rigid grouting pipe; 11. an anchor box; 12. anchor legs; 13. a pin plate; 14. a spring; 15. a chute; 16. a retaining ring; 17. four-way grouting pipe.

Detailed Description

In order that the present invention may be more effectively carried out with the intended purpose and function, the structure, features and embodiments of the present invention will be further described with reference to the accompanying drawings. The detailed description is as follows:

example 1

As shown in fig. 1-9, the biological protection and reinforcement device for the marine pipeline comprises a fixed cable 1 and a grouting anchor 3, wherein the grouting anchor 3 is respectively connected to two ends of the fixed cable 1. The fixed cable 1 covers the top of the marine pipeline 2 in a direction perpendicular to the marine pipeline, and the grouting anchor 3 is anchored in seabed on two sides of the marine pipeline 2, so that the fixed cable 1 is tensioned and fixed on the marine pipeline.

The fixing rope 1 comprises a biological culture rope 5 and a chain 7. The chain 7 connects the biological growth rope 5 and the grouting anchor 3. The chain 7, the biological growth rope 5 and the grouting anchor 3 are connected through a retaining ring 16.

The biological culture rope 5 is formed by twisting two strands of rubber strips with the width of 3 cm, and can clamp fine shellfish seedlings of clustered shellfish 6 into twisted rope seams to provide fine shellfish seeds for later propagation and growth. The shellfish 6 is mussel. Mussels belong to attached offshore bivalve organisms and are distributed in the yellow sea, Bohai sea, east sea and south sea areas in China. The mussel has the advantages of extremely high viability, water temperature of-2-28 ℃, 1.5-30 m of survival water depth, 18-32 per mill of applicable salinity, extremely high pollution resistance, wind resistance and dryness resistance, and extremely high reproductive capacity, and the clustered mussel is firmly adsorbed by secreting byssus and survives on attachments.

The grouting anchor device 3 is integrally of a flat plate structure and comprises a four-way grouting pipe 17 and an anchor box 11. For convenience of description, for the grouting anchor, one end close to the fixed cable is used as a rear end, one end far away from the fixed cable is used as a front end, and the direction perpendicular to the front end and the rear end in the plane of the flat plate is used as a left-right direction. The four-way grouting pipe 17 comprises a grouting main pipe 8 and a grouting auxiliary pipe 9, the grouting main pipe 8 and the grouting auxiliary pipe 9 are arranged in a crossed mode and welded to the upper surface of the anchor box 11, the grouting main pipe 8 extends in the left-right direction, the grouting main pipe 8 is perpendicular to the grouting auxiliary pipe 9, the cross section of the grouting main pipe 8 and the cross section of the grouting auxiliary pipe 9 are semicircular, and the grouting main pipe 8 and the grouting auxiliary pipe 9 form a communicated grouting channel.

Anchor leg 12 is equipped with in the anchor case 11, anchor leg 12 has 2, anchor leg 12 can slide back and forth in the sliding chamber of anchor case 11. A sliding groove 15 is arranged on the upper surface of the anchor box at the corresponding position of the intersection part of the main grouting pipe 8 and the anchor leg 12. A pin plate 13 is fixed in the middle of the anchor leg 12, and the pin plate 13 slides back and forth in the sliding groove 15.

The rear end of the anchor leg 12 is provided with a spring 14, the spring 14 is pre-compressed and arranged in a sliding cavity where the anchor leg is located to provide outward thrust for the anchor leg, and the front end of the anchor leg 12 is a sharp part.

When in use, the method comprises the following steps:

A. prefabricating a fixed cable 1 and an anchor box 3 with proper sizes according to the factors such as the thickness of a pipeline and the like, and connecting the anchor box 3 at two ends of the fixed cable 1;

B. determining the laying position of the marine pipeline 2 by an underwater positioning technology, and arranging grooves parallel to the pipeline on two sides of the marine pipeline 2;

C. applying thrust to the anchor leg 12 to further compress the pre-compressed spring 14, enabling the rigid grouting pipes 10 to respectively penetrate through a plurality of grouting main pipes 8 arranged on the anchor box 3 at intervals, and tightly clamping the rigid grouting pipes 10 by the pin plates 13; the distance between the adjacent fixed cables 1 is 0.6 m;

D. a plurality of anchor boxes connected in series by rigid grouting pipes 10 are preliminarily fixed in a groove on one side of the marine pipeline 2;

E. grouting is carried out through the rigid grouting pipe 10, meanwhile, the rigid grouting pipe 10 is pulled out from the grouting main pipe 8 of the grouting anchor device 3, the clamping force of the rigid grouting pipe 10 on the pin plate 13 disappears when the rigid grouting pipe is pulled out, and the anchor leg is popped out under the thrust of the spring 14, so that the anchor leg 12 is inserted into the seabed; grouting slurry flows out of the main grouting pipe 8 and the auxiliary grouting pipe 9 through the rigid grouting pipe 10 and is fixedly connected with the seabed 4, so that the grouting anchor is further fixed in the seabed 4;

F. the same is done in a groove on the other side of the marine pipeline 2, compressing the cable 1 in the top area of the marine pipeline 2.

Example 2

The fixing rope 1 comprises a biological culture rope 5 and a chain 7. The chain 7 connects the biological growth rope 5 and the grouting anchor 3. The chain 7, the biological growth rope 5 and the grouting anchor 3 are connected through a retaining ring 16. In order to facilitate replacement and adjustment of the length of the fixing cable, the retaining ring 16 is a movable and detachable retaining ring.

The biological culture rope 5 is formed by twisting two strands of rubber strips with the width of 10 cm, and can clamp fine shellfish seedlings of clustered shellfish 6 into twisted rope seams to provide fine shellfish seeds for later propagation and growth. The shellfish 6 is oyster.

The grouting anchorage device 3 and the chain 7 are made of stainless steel materials resisting seawater corrosion, and the surfaces of the grouting anchorage device and the chain 7 are provided with biological adhesion preventing coatings, so that shellfish 6 on the biological culture rope 5 is prevented from spreading and propagating towards the grouting anchorage device 3 and the chain 7 and attenuating the material performance of the grouting anchorage device and the chain.

The grouting anchor device 3 is integrally of a flat plate structure and comprises a four-way grouting pipe 17 and an anchor box 11. The cross-joint grouting pipe 17 comprises a grouting main pipe 8 and a grouting auxiliary pipe 9, the grouting main pipe 8 and the grouting auxiliary pipe 9 are arranged in a crossed mode and welded to the upper surface of the anchor box 11, the grouting main pipe 8 extends along the left-right direction, the grouting main pipe 8 is perpendicular to the grouting auxiliary pipe 9, the cross section of the grouting main pipe 8 and the grouting auxiliary pipe 9 is semi-oval, and the grouting main pipe 8 and the grouting auxiliary pipe 9 form a communicated grouting channel.

The rear end of the anchor leg 12 is provided with a spring 14, and the front end of the anchor leg 12 is a sharp part.

When in use, the method comprises the following steps:

A. prefabricating a fixed cable 1 and a grouting anchor 3 with proper sizes according to the factors such as the thickness of a pipeline and the like, and connecting the fixed cable 1 with the grouting anchor 3;

C. applying thrust to the anchor legs 12 to further compress the pre-compressed springs 14, enabling the rigid grouting pipes 10 to respectively penetrate through the grouting main pipes 8 on the grouting anchors 3 arranged at intervals, and tightly clamping the rigid grouting pipes 10 by the pin plates 13; the rigid grouting pipe 10 is connected with a construction ship and used for fixing a grouting anchor and conveying grouting slurry; the distance between the adjacent fixed cables 1 is 3 meters;

E. grouting is carried out through the rigid grouting pipe 10, meanwhile, the rigid grouting pipe 10 is pulled out from the grouting main pipe 8 of the grouting anchor device 3, the clamping force of the rigid grouting pipe 10 on the pin plate 13 disappears when the rigid grouting pipe is pulled out, and the anchor leg is popped out under the thrust of the spring 14, so that the anchor leg 12 is inserted into the seabed; the grouting slurry is consolidated with the seabed so that the grouting anchor 3 is further fixed in the seabed 4; the grouting slurry is cement-water glass slurry, the ratio of cement to water glass is 1:1, and the slurry can be rapidly solidified under the condition of running water by the preparation ratio of the slurry.

F. The same is done in a groove on the other side of the marine pipeline 2, with the retainer cable 1 pressed against the top area of the marine pipeline 2, and in order to prevent the retainer cable from shifting, a catch, detent or spacer is provided between the retainer cable 1 and the marine pipeline 2.

G. The adjacent fixing cables 1 are connected through a biological cultivation rope 5 to form a net structure, so that the overall reinforcement and anti-scouring effects can be further improved.

On one hand, the formed bilateral cable-stayed fixing cable can effectively attach the submarine pipeline to the seabed so as to play a role in fixing; on the other hand, the earlier-stage biological culture ropes form bilateral biological sacrificial piles, the later-stage shellfish is propagated in a large quantity, and continuous biological water retaining walls are formed between the adjacent biological culture ropes, so that the erosion and corrosion of water flow to the sediment at the bottom of the submarine pipeline can be effectively inhibited.

Compared with the prior art, the invention fully combines the biological culture technology with the grouting anchoring technology, can reinforce the marine pipeline and effectively prevent and treat the scouring disaster of the marine pipeline at the same time, and has strong flow direction adaptability and better active protection effect compared with the traditional sacrificial pile protection; compared with the traditional riprap protection, the invention has strong integrity and long passive protection period. Meanwhile, the invention is based on the marine environment, the marine organism mussel is used as the protective material, the ecological friendliness is extremely strong, the cultivation can be repeatedly recycled, the economic benefit is better, and the combination of the tube-based protection and the aquaculture can be realized.

The invention has been described above with reference to a preferred embodiment, but the scope of protection of the invention is not limited thereto, and various modifications can be made and equivalents can be substituted for elements thereof without departing from the scope of the invention, and features mentioned in the various embodiments can be combined in any way as long as there is no structural conflict, and any reference sign in the claims should not be construed as limiting the claim concerned, from which the embodiment is to be regarded as being exemplary and non-limiting in any way. Therefore, all technical solutions that fall within the scope of the claims are within the scope of the present invention.

Claims

1. The utility model provides a biological protection reinforcing apparatus of marine pipeline, includes fixed cable (1), slip casting ground tackle (3), fixed cable (1) both ends are connected with slip casting ground tackle (3) respectively, its characterized in that:

the fixed rope (1) comprises a biological culture rope (5) and a chain (7); the chain (7) is connected with the biological growth rope (5) and the grouting anchor (3);

the grouting anchor (3) is integrally of a flat plate structure and comprises a four-way grouting pipe (17) and an anchor box (11); the four-way grouting pipe (17) comprises a main grouting pipe (8) and an auxiliary grouting pipe (9), the main grouting pipe (8) and the auxiliary grouting pipe (9) are arranged in a crossed mode and welded to the upper surface of the anchor box (11), the main grouting pipe (8) extends in the left-right direction, the main grouting pipe (8) is perpendicular to the auxiliary grouting pipe (9), and the main grouting pipe (8) and the auxiliary grouting pipe (9) form a communicated grouting channel; anchor legs (12) are arranged in the anchor box (11), and the anchor legs (12) slide back and forth in a sliding cavity of the anchor box (11); a sliding groove (15) is formed in the upper surface of the anchor box at the corresponding position of the intersection part of the grouting main pipe (8) and the anchor leg (12); a pin plate (13) is fixed in the middle of the anchor leg (12), and the pin plate (13) slides forwards and backwards in the sliding groove (15); the rear end of each anchor leg (12) is provided with a spring (14), and the front end of each anchor leg (12) is a sharp part.

2. The biological protection and reinforcement device for marine pipelines according to claim 1, wherein the chain (7), the biological growth rope (5) and the grouting anchor (3) are connected through a retaining ring (16), and the retaining ring (16) is a movable and detachable retaining ring.

3. The device for the biological protection and reinforcement of marine pipelines according to any one of claims 1-2, wherein the biological growth rope (5) is formed by twisting two 3-10 cm wide strips of rubber skin for sandwiching elite shellfish seedlings of clustered shellfish (6) into the twisted rope gaps.

4. A biological protection and reinforcement device for marine pipelines according to claim 3, characterized in that said shellfish (6) is mussel, scallop, oyster or barnacle.

5. The biological protection and reinforcement device for marine pipelines according to any one of claims 1-2, wherein the grouting anchors (3) and the chain (7) are made of stainless steel materials resistant to seawater corrosion, and the surface of the grouting anchors is provided with a biological adhesion prevention coating.

6. The biological protection and reinforcement device for marine pipelines according to any one of claims 1-2, characterized in that the cross sections of the main grouting pipe (8) and the auxiliary grouting pipe (9) are semicircular or semielliptical.

7. The use method of the biological protection and reinforcement device for the marine pipeline according to any one of claims 1-6, characterized by comprising the following steps:

A. prefabricating a fixed cable (1) and a grouting anchor (3) with proper sizes, and connecting the fixed cable (1) and the grouting anchor (3);

B. determining the laying position of the marine pipeline (2) by an underwater positioning technology, and arranging grooves parallel to the pipeline on two sides of the marine pipeline (2);

C. applying thrust to the anchor legs (12) to further compress the pre-compressed springs (14), enabling the rigid grouting pipes (10) to respectively penetrate through grouting main pipes (8) on a plurality of grouting anchors (3) arranged at intervals, and clamping the rigid grouting pipes (10) by pin plates (13); the rigid grouting pipe (10) is connected with a construction ship and used for fixing a grouting anchor and conveying grouting slurry;

D. a plurality of anchor boxes connected in series by rigid grouting pipes (10) are preliminarily fixed in a groove on one side of an ocean pipeline (2);

E. grouting is carried out through the rigid grouting pipe (10), the rigid grouting pipe (10) is pulled out from a grouting main pipe (8) of the grouting anchor (3), the clamping force of the rigid grouting pipe (10) on the pin plate (13) disappears when the rigid grouting pipe is pulled out, the anchor leg is popped out under the thrust of the spring (14), and the anchor leg (12) is inserted into the seabed; the grouting slurry is consolidated with the seabed, so that the grouting anchor (3) is further fixed in the seabed (4);

F. the same is done in the groove on the other side of the marine pipeline (2) so that the fixing cable (1) is pressed against the top area of the marine pipeline (2).

8. The use method of the biological protection and reinforcement device for the marine pipeline according to claim 7, wherein the grouting slurry is cement water glass slurry, and the ratio of cement to water glass is 1: 1.

9. The use method of the biological protection and reinforcement device for the marine pipeline according to claim 7, wherein the distance between the adjacent fixing cables (1) is 0.5-3 m.

10. The method for using the biological protection and reinforcement device for the marine pipeline according to claim 7, further comprising a step G of connecting the adjacent fixing cables (1) through biological growing ropes (5) to form a net structure.