Cable laying and burying construction method for seabed reef section

Abstract

The invention discloses a cable laying and burying construction method for a seabed reef section, and the method comprises the following steps: 1, recovering a burying machine: when a cable is laid and buried to the outer edge of the seabed reef section, throwing a positioning mooring ship by a workboat to open an anchor in a splayed manner so as to fix a ship position, and recovering the burying machine; step 2, mounting a joint sleeve; 3, laying a cable on the seabed reef section; step 4, paving the concrete interlocking row; and step 5, diving inspection: the diver enters the water for inspection, after confirming that the diver passes through the reef area, putting the burying machine again, withdrawing the ship stabilizing anchor, and continuing to carry out normal laying and burying construction along the advancing direction of the route. According to the invention, a throwing laying construction mode of joint sleeve protection is adopted for the submarine cable, the problem that the submarine cable is damaged or damaged due to long-term scouring of seabed seawater is solved, particularly, the joint sleeve is firmly pressed and fixed on the seabed surface by using the concrete interlocking row, the submarine cable cannot be pulled due to the action of the seawater, and the submarine cable is prevented from being damaged. Therefore, the service life of the submarine cable is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of submarine cable installation construction, in particular to a cable burying construction method in a submarine reef section. Background Art

[0002] Submarine cables are the most important equipment in submarine power transmission projects. They can cross straits and rivers to connect regional power grids. With the vigorous development of wind power, the demand for submarine cables is increasing. There are two existing methods for constructing submarine cables: throwing and laying, and deep burial. The throwing method uses the weight of the submarine cable to sink to the seabed. It is simple to construct, but its safety is poor. It is very easy to be damaged by fishing and anchors in shallow fishing areas. The deep burial method uses burial equipment, i.e., burial machines, to bury the submarine cable at a certain depth under the seabed to avoid damage caused by human operations. It is safer. At present, affected by the marine regional environment, marine hydrology, construction equipment and technology, submarine cables are currently mainly constructed using deep burial methods.

[0003] However, in the laying route of the cable route track, if there is a reef area on the seabed, it is difficult to use a seabed trenching tool to dig a trench in the reef in the reef laying section of the submarine cable due to the hard reef, so as to bury the submarine cable deeply in the trench. At this time, the only construction method is to use the throwing laying method. The submarine cable will be damaged or damaged due to the long-term scouring of the seawater on the seabed, thereby shortening the service life of the submarine cable. Summary of the invention

[0004] The purpose of the present invention is to provide a cable burying construction method in a submarine reef section, which can effectively protect the submarine cable and solve the problem of submarine cables being destroyed or damaged due to long-term scouring by seawater on the seabed, thereby extending the service life of the submarine cable.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: A cable burying construction method in a submarine reef section comprises the following steps: Step 1: Recover the burying machine: When the cable is buried to the outer edge of the seabed reef section, the construction ship drops the positioning mooring ship and opens the anchor to fix the ship's position, and recovers the burying machine; Step 2: Install the joint sleeve: On the deck of the construction vessel, install the joint sleeve on the cable and fix it with a self-locking fastener; Step 3, laying cables in the submarine reef section: using the DGPS navigation and positioning system for positioning, the construction vessel is moved along the route direction by adjusting the length of the anchor cable, and the cable installed with the joint casing is laid to the seabed surface of the submarine reef section. The casing is installed while the construction vessel is moved until the cable installed with the joint casing is laid in the entire submarine reef section; Step 4: Paving of concrete interlocking rows: hoisting the concrete interlocking rows to the seabed and making the concrete interlocking rows cover the surface of the submarine cable installed with the joint casing; Step 5: Diving inspection: Divers enter the water to check and confirm that the reef area has been passed. Then, they re-deploy the burying machine, retrieve the anchor, and continue the normal burying construction along the route.

[0006] Further, in step 4, the center line of the concrete interlocking row is consistent with the axis of the submarine cable.

[0007] Furthermore, in step 4, during the laying process of the concrete interlocking rows, they are laid one by one according to the route and direction of the submarine cable laying, and the overlapping method is adopted between two adjacent concrete interlocking rows. The laying process is carried out in a smooth manner to avoid wrinkles.

[0008] Furthermore, in step 2, the joint sleeve is a ductile iron Hough joint sleeve.

[0009] Furthermore, the pipe section length of the ductile iron Hough joint is 0.5-1.0m, the allowable deviation of the wall thickness is +1.5mm, the inner diameter deviation does not exceed ±5mm, the allowable length deviation is ±50mm, the straightness deviation does not exceed 0.125% of the length, and the ovality does not exceed 1%; the self-anchoring interface is a Hough ball joint, which allows unimpeded rotation within the range of motion, and the strength of the ball joint is not lower than the strength of the casing body section.

[0010] Furthermore, the self-locking fasteners are rust-proof bolts, the tensile strength of the bolts is not lower than the material strength of the ductile iron pipe itself, and the service life is not less than the design service life of this project.

[0011] Further, in step 2, the method for installing the joint sleeve on the cable is as follows: step 2.1, clean the surface of the joint sleeve, check whether the joint sleeve has casting defects that affect the performance of the ductile iron pipe, if found, replace it in time, and withdraw the pipe fittings that do not meet the requirements; step 2.2, the two halves of the joint sleeve symmetrically clamp the cable, and the semicircular saddles on the two halves of the joint sleeve are aligned; step 2.3, tighten the stainless steel bolts to fix it.

[0012] Furthermore, in step 4, the installation method of the concrete interlocking bar is as follows: Step 4.1, Transportation of concrete interlocking bars: The crane on the crane ship hoists the concrete interlocking bars from the car box at the dock to the crane ship, and the crane ship travels to the construction area; Step 4.2, ship positioning: under the command of the crane ship captain and positioning personnel, the anchoring boat transports the engineering anchor to the designated anchoring point in turn to anchor and position the crane ship; Step 4.3, cable exploration: Divers explore the submarine cables that need gland construction and accurately locate the submarine cables; Step 4.4, hoisting concrete interlocking row: install the automatic release hanger on the crane, hang the concrete interlocking row on the hook of the automatic release hanger and close the hook; Step 4.5, laying concrete interlocking row: After the crane moves the concrete interlocking row to the top of the designed installation position of the submarine cable, the crane starts to lower the concrete interlocking row underwater, and adjusts the position and posture of the concrete interlocking row according to the USBL positioning data until the concrete interlocking row touches the seabed; Step 4.6, check the laying position: Divers monitor the underwater position and status of the concrete interlocking row throughout the process. If the position of the concrete interlocking row is not ideal, the crane will pull it up and readjust it before lowering it to the bottom; Step 4.7, release the concrete interlocking row and proceed to lay the next concrete interlocking row: open the hook, wait until the hook is fully opened, lift the crane, observe whether there is weight on the crane dynamometer, separate the concrete interlocking row from the automatic release hanger, and use the crane to drive the automatic release hanger to reset, and proceed to lay the next concrete interlocking row until all the concrete interlocking rows are laid.

[0013] Furthermore, in step 4.2, the crane vessel uses the DGPS positioning system as a navigation and positioning system. The positioning personnel input the coordinate data of the anchor point into the navigation and positioning system. The navigation and positioning system displays the actual position of the crane vessel and the position of the submarine cable in the construction area in real time and displays them on the computer screen to ensure that the crane vessel can operate safely and accurately above the submarine cable.

[0014] Furthermore, in step 4.5, the tidal current and wave strength and direction during the construction period should be detected before construction, and the entry position of the concrete interlocking drainage pipe into the water is determined by the specific water flow direction and flow rate.

[0015] The beneficial effects of the present invention are: The invention adopts a joint sleeve protection throwing and laying construction method for the submarine cable, which solves the problem of the submarine cable being destroyed or damaged due to long-term scouring of seawater on the seabed. In particular, the joint sleeve is firmly pressed and fixed on the seabed surface by using concrete interlocking rows, so that the submarine cable will not be pulled by the action of seawater, thereby extending the service life of the submarine cable.

[0016] The present invention adopts a construction method of installing the casing while moving the construction ship, and the installation can be completed on board without underwater construction. Not only is the construction efficiency high, but the risk of personal injury caused by underwater operations is also avoided.

[0017] The present invention also provides an installation construction method for the concrete interlocking row, which not only makes the submarine installation construction of the concrete interlocking row safer and more efficient, but also improves the installation accuracy of the concrete interlocking row. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flow chart of the cable laying and burying construction method of the submarine reef section of the present invention; Figure 2 This is a construction status diagram after the concrete interlocking row of the present invention is paved; Figure 3 for Figure 2 Side view shown; Figure 4 The figure is a flow chart of the concrete interlocking bar installation method of the present invention. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other without conflict.

[0020] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper surface", "lower surface", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "forward", "reverse", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0021] like Figure 1 As shown, a cable burying construction method in a submarine reef section includes the following steps: Step 1: Recover the burying machine: When the cable is buried to the outer edge of the seabed reef section, the construction vessel drops the positioning mooring and opens the anchor to fix the ship's position and retrieve the burying machine.

[0022] Step 2: Install the joint sleeve: On the deck of the construction ship, the joint sleeve is installed on the cable and fixed with a self-locking fastener; the joint sleeve adopts a ductile iron half joint sleeve. The pipe section length of the ductile iron half joint is 0.5-1.0m, the allowable deviation of the wall thickness is +1.5mm, the inner diameter deviation does not exceed ±5mm, the allowable deviation of the length is ±50mm, the straightness deviation does not exceed 0.125% of the length, and the ovality does not exceed 1%; the self-anchoring interface is a half ball joint, which allows unimpeded rotation within the range of motion, and the strength at the ball joint is not lower than the strength of the sleeve body section. The self-locking fasteners adopt rust-proof bolts, the tensile strength of the bolts is not lower than the material strength of the ductile iron pipe itself, and the service life is not less than the design service life of this project.

[0023] The method for installing the joint sleeve on the cable is as follows: Step 2.1, clean the surface of the joint sleeve, check whether the joint sleeve has casting defects that affect the performance of the ductile iron pipe, if found, replace it in time, and remove the pipe fittings that do not meet the requirements; Step 2.2, the two halves of the joint sleeve clamp the cable symmetrically, and align the semicircular saddles on the two halves of the joint sleeve; Step 2.3, tighten the stainless steel bolts to fix it.

[0024] Step 3: Laying cables on the seabed reef section: The DGPS navigation and positioning system is used for positioning. The construction vessel is moved along the route direction by adjusting the length of the anchor cable, and the cable installed with the joint casing is laid to the seabed surface of the submarine reef section. The casing is installed while the construction vessel is moved until the cable installed with the joint casing is laid throughout the submarine reef section. The present invention adopts a construction method of moving the construction vessel while installing the casing. The installation can be completed on board without underwater construction. Not only is the construction efficiency high, but the risk of personal injury caused by underwater operations is also avoided.

[0025] Step 4: Paving of interlocking concrete rows: like Figure 2 , 3 As shown, the concrete interlocking row is hoisted to the seabed, and the concrete interlocking row 3 is covered on the surface of the submarine cable 1 installed with the joint sleeve 2, and the center line of the concrete interlocking row is consistent with the axis of the submarine cable; during the laying process of the concrete interlocking row, it is laid piece by piece according to the route and direction of the submarine cable laying, and the overlapping method is adopted between two adjacent concrete interlocking rows, and the laying is made to be flat to avoid wrinkles.

[0026] The concrete interlocking row 3 is composed of a plurality of cement precast blocks arranged in an array, and adjacent cement precast blocks are connected by ropes. The cement precast blocks at the edge of the concrete interlocking row 3 are provided with lifting rings for connecting with the hooks of the automatic release hanger on the crane.

[0027] The invention adopts a joint sleeve protection throwing and laying construction method for the submarine cable, which solves the problem of the submarine cable being destroyed or damaged due to long-term scouring of seawater on the seabed. In particular, the joint sleeve is firmly pressed and fixed on the seabed surface by using concrete interlocking rows, so that the submarine cable will not be pulled by the action of seawater, thereby extending the service life of the submarine cable.

[0028] like Figure 4 As shown, the installation method of the concrete interlocking bar is as follows: Step 4.1, Transportation of concrete interlocking bars: The crane on the crane ship lifts the concrete interlocking bars from the car box at the dock to the crane ship, and the crane ship travels to the construction area.

[0029] Step 4.2, ship positioning: Under the command of the crane ship captain and positioning personnel, the anchoring boat transports the engineering anchor to the designated anchoring point in turn to anchor the crane ship; the crane ship uses the DGPS positioning system as the navigation and positioning system, and the positioning personnel enter the anchor point coordinate data into the navigation and positioning system. The navigation and positioning system displays the actual position of the crane ship and the position of the submarine cable in the construction area in real time, and displays it on the computer screen to ensure the crane ship's safe operation and accurate positioning above the submarine cable.

[0030] Step 4.3, cable exploration: Divers explore the submarine cables that need gland construction and accurately locate the submarine cables; Step 4.4, hoisting concrete interlocking bar: install the automatic release hanger on the crane, hang the lifting ring on the concrete interlocking bar to the hook of the automatic release hanger and close the hook; Step 4.5, laying concrete interlocking rows: After the crane moves the concrete interlocking rows to the top of the designed installation position of the submarine cable, the crane begins to lower the concrete interlocking rows underwater, and adjusts the position and posture of the concrete interlocking rows according to the USBL positioning data until the concrete interlocking rows touch the seabed; before construction, the tidal current and wave intensity and direction during the construction period should be tested, and the entry position of the concrete interlocking rows underwater is determined by the specific water flow direction and flow rate.

[0031] Step 4.6, check the laying position: Divers monitor the underwater position and status of the concrete interlocking row throughout the process. If the position of the concrete interlocking row is not ideal, the crane will pull it up and readjust it before lowering it to the bottom; Step 4.7, release the concrete interlocking row and proceed to lay the next concrete interlocking row: open the hook, wait until the hook is fully opened, lift the crane, observe whether there is weight on the crane dynamometer, separate the concrete interlocking row from the automatic release hanger, and use the crane to drive the automatic release hanger to reset, and proceed to lay the next concrete interlocking row until all the concrete interlocking rows are laid.

[0032] Step 5: Diving inspection: Divers enter the water to check and confirm that the reef area has been passed. Then, they re-deploy the burying machine, retrieve the anchor, and continue the normal burying construction along the route.

[0033] The above-mentioned installation construction method of the concrete interlocking row of the present invention not only makes the submarine installation construction of the concrete interlocking row safer and more efficient, but also improves the installation accuracy of the concrete interlocking row.

[0034] In addition, those skilled in the art may combine and combine the different embodiments or examples and the features of the different embodiments or examples described in this specification without contradiction. Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A cable laying construction method for a submarine reef section, characterized in that: The following steps are involved: Step 1: Recover the burying machine: When the cable is buried to the outer edge of the seabed reef section, the construction ship drops the positioning mooring ship and opens the anchor to fix the ship's position, and recovers the burying machine; Step 2: Install the joint sleeve: On the deck of the construction vessel, install the joint sleeve on the cable and fix it with a self-locking fastener; Step 3, laying cables in the submarine reef section: using the DGPS navigation and positioning system for positioning, the construction vessel is moved along the route direction by adjusting the length of the anchor cable, and the cable installed with the joint casing is laid to the seabed surface of the submarine reef section. The casing is installed while the construction vessel is moved until the cable installed with the joint casing is laid in the entire submarine reef section; Step 4: Paving of concrete interlocking rows: hoisting the concrete interlocking rows to the seabed and making the concrete interlocking rows cover the surface of the submarine cable installed with the joint casing; Step 5: Diving inspection: Divers enter the water to check and confirm that the reef area has been passed. Then, they re-deploy the burying machine, retrieve the anchor, and continue the normal burying construction along the route.

2. The cable laying and burying construction method of the submarine reef section according to claim 1 is characterized by: In step 4, the center line of the concrete interlocking row is consistent with the axis of the submarine cable.

3. The cable laying and burying construction method in the submarine reef section according to claim 1 is characterized by: In step 4, during the laying process of the concrete interlocking rows, they are laid one by one according to the route and direction of the submarine cable laying, and the overlapping method is adopted between two adjacent concrete interlocking rows. When laying, it is strived to be flat and avoid wrinkles.

4. The cable laying and burying construction method in the submarine reef section according to claim 1 is characterized in that: In step 2, the joint sleeve is a ductile iron Hough joint sleeve.

5. The cable laying and burying construction method in the submarine reef section according to claim 3 is characterized by: The pipe section length of the ductile iron Hough joint is 0.5-1.0m, the allowable deviation of wall thickness is +1.5mm, the inner diameter deviation does not exceed ±5mm, the allowable length deviation is ±50mm, the straightness deviation does not exceed 0.125% of the length, and the ovality does not exceed 1%; the self-anchoring interface is a Hough ball joint, which allows unimpeded rotation within the range of motion, and the strength of the ball joint is not lower than the strength of the casing body section.

6. The cable laying and burying construction method in the submarine reef section according to claim 1 is characterized by: In step 2, the self-locking fasteners are rust-proof bolts, the tensile strength of the bolts is not less than the material strength of the ductile iron pipe itself, and the service life is not less than the design service life of this project.

7. The cable laying and burying construction method of the submarine reef section according to claim 1 is characterized in that: In step 2, the method for installing the joint sleeve on the cable is as follows: Step 2.1, clean the surface of the joint sleeve, check whether the joint sleeve has casting defects that affect the performance of the ductile iron pipe, if found, replace it in time, and remove the pipe fittings that do not meet the requirements; Step 2.2, the two halves of the joint sleeve clamp the cable symmetrically, and the semicircular saddles on the two halves of the joint sleeve are aligned; Step 2.3, tighten the stainless steel bolts to fix it.

8. The cable burying construction method in the submarine reef section according to claim 1 is characterized in that: In step 4, the installation method of the concrete interlocking bar is as follows: Step 4.1, Transportation of concrete interlocking bars: The crane on the crane ship hoists the concrete interlocking bars from the car box at the dock to the crane ship, and the crane ship travels to the construction area; Step 4.2, ship positioning: under the command of the crane ship captain and positioning personnel, the anchoring boat transports the engineering anchor to the designated anchoring point in turn and anchors the crane ship; Step 4.3, cable exploration: Divers explore the submarine cables that need gland construction and accurately locate the submarine cables; Step 4.4, hoisting concrete interlocking row: install the automatic release hanger on the crane, hang the concrete interlocking row on the hook of the automatic release hanger and close the hook; Step 4.5, laying concrete interlocking row: After the crane moves the concrete interlocking row to the top of the designed installation position of the submarine cable, the crane starts to lower the concrete interlocking row underwater, and adjusts the position and posture of the concrete interlocking row according to the USBL positioning data until the concrete interlocking row touches the seabed; Step 4.6, check the laying position: Divers monitor the underwater position and status of the concrete interlocking row throughout the process. If the position of the concrete interlocking row is not ideal, the crane will pull it up and readjust it before lowering it to the bottom; Step 4.7, release the concrete interlocking row and proceed to lay the next concrete interlocking row: open the hook, wait until the hook is fully opened, lift the crane, observe whether there is weight on the crane dynamometer, separate the concrete interlocking row from the automatic release hanger, and use the crane to drive the automatic release hanger to reset, and proceed to lay the next concrete interlocking row until all the concrete interlocking rows are laid.

9. The cable laying and burying construction method in the submarine reef section according to claim 8 is characterized by: In step 4.2, the crane vessel uses the DGPS positioning system as the navigation and positioning system. The positioning personnel input the coordinate data of the anchor point into the navigation and positioning system. The navigation and positioning system displays the actual position of the crane vessel and the position of the submarine cable in the construction area in real time and displays them on the computer screen to ensure that the crane vessel can operate safely and accurately above the submarine cable.

10. The cable laying and burying construction method in the submarine reef section according to claim 8 is characterized by: In step 4.5, the tidal current and wave strength and direction during the construction period should be tested before construction, and the entry position of the concrete interlocking drainage pipe into the water is determined by the specific water flow direction and flow rate.

Images