Construction method for underwater butt joint of steel casings

Abstract

According to the construction method, a circle of inner side guide blocks and a circle of outer side guide blocks are arranged on the inner side and the outer side of a lower opening of a to-be-lengthened steel casing correspondingly, and the to-be-lengthened steel casing is hoisted through a crane; the middle gap between the inner side guide block and the outer side guide block of the to-be-lengthened steel casing is inserted into the upper opening of the underwater steel casing, underwater butt joint of the to-be-lengthened steel casing and the underwater steel casing is completed, underwater welding or arrangement of a connecting flange in advance is not needed, construction is easy and convenient, limitation is small, the underwater butt joint problem of the steel casing can be rapidly and effectively solved, and the construction efficiency is improved. The construction efficiency is improved, the construction period is shortened and the construction cost is reduced; joint sealing is completed through double protection of cotton and a plugging agent, the sealing effect is good, a water head in a hole can be guaranteed during drilling construction, and the drilling progress is recovered. The welding operation of the inner side guide block and the outer side guide block of the lower opening of the steel casing to be lengthened is carried out on the shore, the underwater operation time is short, and the construction difficulty and the construction safety risk are greatly reduced.

Description

Technical Field

[0001] The invention relates to the fields of wind power and bridge pile foundation construction, and in particular to a construction method for underwater docking of steel casings. Background Art

[0002] In the construction of bridge foundations and offshore wind power rock-embedded foundations, pile foundation construction is an extremely critical link, and steel casing, as an important component of pile foundation construction, plays an indispensable role. Due to water level changes, local deformation of steel casing underwater after cutting, and other special circumstances, underwater docking and extension construction of steel casing is required. Conventional underwater steel casing connection usually adopts underwater electric welding technology, but there are problems such as high construction difficulty, high safety risk, and unstable welding quality; or it is necessary to set a connecting flange at the upper end of the steel casing in advance and use bolt connection method to extend it, which has great limitations.

[0003] With the continuous expansion of engineering construction scale and the improvement of technical requirements, more efficient underwater steel casing docking technology is urgently needed to shorten the construction period, reduce costs and ensure the smooth progress of drilling construction. Summary of the invention

[0004] The purpose of the present invention is to provide a construction method for underwater docking of steel casings, which can quickly and effectively solve the problem of underwater docking of steel casings, does not require underwater welding or pre-setting of connecting flanges, is simple to construct and has few limitations, improves construction efficiency, and shortens construction period.

[0005] The object of the present invention is achieved in that: A construction method for underwater docking of steel casings, characterized by the following specific steps: A. Before the steel casing to be connected, first weld a circle of several slightly spaced inner guide blocks and several slightly spaced outer guide blocks on the inner and outer sides of the lower end of the steel casing to be connected on land or on the deck of the ship, with hf ≥ 10mm; the curvature of the inner guide block and the outer guide block are consistent with the steel casing to be connected, and they are close to the steel casing to be connected; the inner guide block and the outer guide block are staggered, with one inner guide block facing the gap between the two outer guide blocks, and one outer guide block facing the gap between the two inner guide blocks; B. After the inner guide block and the outer guide block are welded, cotton is stuffed into the gap between the inner guide block and the outer guide block and filled tightly; C. Bend the inner guide plate of the inner guide block toward the center of the steel casing to be connected, so that the inner guide plate forms an angle of 15°-45° with the vertical inner guide block, and the outer guide plate of the outer guide block remains unchanged for subsequent docking; D. Use a crane to lift the steel casing to be connected. The diver commands the crane at the top of the underwater steel casing to be connected and accurately adjusts the position so that the gap between the inner guide block and the outer guide block of the steel casing to be connected is inserted into the upper end of the underwater steel casing to complete the underwater connection between the steel casing to be connected and the underwater steel casing; E. After the steel casing is connected, a vibrating hammer is used to vibrate the steel casing to be connected, and the steel casing to be connected is vibrated and sunk. After the steel casing to be connected is stable, the diver enters the interior of the steel casing to be connected and cuts off the inner guide plate bent upward by the inner guide block; F. Divers go into the water and evenly apply the Leak-proof King on both sides of the inner and outer joints of the steel casing to be connected and the underwater steel casing to complete further sealing.

[0006] Furthermore, in step A, an inner guide plate is provided downward in the middle of the bottom of the inner guide block, and its width is smaller than that of the inner guide block; an outer guide plate is provided downward in the middle of the bottom of the outer guide block, and its width is smaller than that of the outer guide block.

[0007] Furthermore, in step A, the bottom end of the lower opening of the steel casing to be extended is clamped between the middle parts of the inner guide block and the outer guide block.

[0008] Compared with the prior art, the advantages of the present invention are: 1. The present invention arranges a circle of inner guide blocks and outer guide blocks on both sides of the inner and outer sides of the lower end of the steel casing to be connected, and uses a crane to lift the steel casing to be connected, so that the gap between the inner guide block and the outer guide block of the steel casing to be connected is inserted into the upper end of the underwater steel casing, and the underwater docking of the steel casing to be connected and the underwater steel casing is completed, without underwater welding or setting a connecting flange in advance. The construction is simple and has little limitation. The problem of underwater docking of steel casings can be quickly and effectively handled, the construction efficiency is improved, the construction period is shortened, the investment in machinery and equipment is reduced, and the construction cost is reduced; 2. The joint is sealed through the double protection of cotton and leak-proof king, with good sealing effect. During drilling construction, the water head in the hole can be guaranteed and the drilling progress can be restored; 3. The welding work of the inner guide block and the outer guide block of the lower end of the steel casing to be connected is carried out on shore, and the underwater operation time is short, which greatly reduces the construction difficulty and construction safety risks; 4. Only one layer of outer guide block is welded on the outer side of the lower end of the steel casing to be connected, and the outer diameter of the lower end of the steel casing to be connected does not change much, so that the construction method of underwater docking of the steel casing has a wider application range; 5. Several inner guide blocks and several outer guide blocks are slightly spaced apart to facilitate welding and ensure welding quality, and to ensure that the inner and outer guide blocks remain stable when the steel casing is butted and vibrated by a vibrating hammer. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 The construction drawing of the underwater docking step A of the steel casing (excluding the inner guide block and inner guide plate); Figure 2 This is the construction drawing of the underwater docking step B of the steel casing; Figure 3 for Figure 2 A magnified image of area A; Figure 4 It is a top view of the underwater docking of the steel casing; Figure 5 It is a side view of the underwater docking of steel casing. DETAILED DESCRIPTION

[0010] The present invention will be further described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0011] Combined with Figure 1-4 , a construction method for underwater docking of steel casing, the specific steps are as follows: A. Before the steel casing 1 to be connected is butted, a circle of several slightly spaced inner guide blocks 4 and several slightly spaced outer guide blocks 2 are welded on the inner and outer sides of the lower opening of the steel casing 1 to be connected on land or on the deck of a ship, with hf ≥ 10 mm; the inner guide block 4 and the outer guide block 2 have the same curvature as the steel casing 1 to be connected, and are close to the steel casing 1 to be connected; the inner guide block 4 and the outer guide block 2 are staggered, one inner guide block 4 faces the gap between the two outer guide blocks 2, and one outer guide block 2 faces the gap between the two inner guide blocks 4; an inner guide plate 3 with a width smaller than that of the inner guide block 4 is provided in the middle of the bottom of the inner guide block 4, and an outer guide plate 5 with a width smaller than that of the outer guide block 2 is provided in the middle of the bottom of the outer guide block 2; the bottom end of the lower opening of the steel casing 1 to be connected is clamped between the middle of the inner guide block 4 and the outer guide block 2; B. After the inner guide block 4 and the outer guide block 2 are welded, cotton 6 is stuffed into the gap between the inner guide block 4 and the outer guide block 2 and filled tightly; C. Bend the inner guide plate 3 of the inner guide block 4 toward the center of the steel casing 1 to be connected, so that the inner guide plate 3 forms an angle of 15° to 45° with the vertical inner guide block 4, and the outer guide plate 5 of the outer guide block 2 remains unchanged for subsequent docking; D. Use a crane to lift the steel casing 1 to be connected. The diver commands the crane at the top of the underwater steel casing 8 to be connected, and accurately adjusts the position so that the gap between the inner guide block 4 and the outer guide block 2 of the steel casing 1 to be connected is inserted into the upper mouth of the underwater steel casing 8, completing the underwater docking of the steel casing 1 to be connected and the underwater steel casing 8; E. After the steel casing is connected, the steel casing 1 to be connected is vibrated by a vibrating hammer to sink the steel casing 1 to be connected. After the steel casing 1 to be connected is stable, the diver enters the interior of the steel casing 1 to be connected and cuts off the inner guide plate 3 bent upward by the inner guide block 4; F. Divers go into the water and evenly apply the leak-proof sealant 7 on both sides of the butt joint between the steel casing 1 to be connected and the underwater steel casing 8 to complete further sealing.

[0012] The present invention is not limited to the above-mentioned optimal implementation mode. Anyone should be aware that any structural changes made under the inspiration of the present invention, and any technical solutions that are the same or similar to the present invention, fall within the protection scope of the present invention.

Claims

1. A construction method for underwater docking of steel casings, characterized in that: The specific steps are as follows: A. Before the steel casing to be connected, first weld a circle of several slightly spaced inner guide blocks and several slightly spaced outer guide blocks on the inner and outer sides of the lower end of the steel casing to be connected on land or on the deck of the ship, with hf ≥ 10mm; the curvature of the inner guide block and the outer guide block are consistent with the steel casing to be connected, and they are close to the steel casing to be connected; the inner guide block and the outer guide block are staggered, with one inner guide block facing the gap between the two outer guide blocks, and one outer guide block facing the gap between the two inner guide blocks; B. After the inner guide block and the outer guide block are welded, cotton is stuffed into the gap between the inner guide block and the outer guide block and filled tightly; C. Bend the inner guide plate of the inner guide block toward the center of the steel casing to be connected, so that the inner guide plate forms an angle of 15°-45° with the vertical inner guide block, and the outer guide plate of the outer guide block remains unchanged for subsequent docking; D. Use a crane to lift the steel casing to be connected. The diver commands the crane at the top of the underwater steel casing to be connected and accurately adjusts the position so that the gap between the inner guide block and the outer guide block of the steel casing to be connected is inserted into the upper end of the underwater steel casing to complete the underwater connection between the steel casing to be connected and the underwater steel casing; E. After the steel casing is connected, a vibrating hammer is used to vibrate the steel casing to be connected, and the steel casing to be connected is vibrated and sunk. After the steel casing to be connected is stable, the diver enters the interior of the steel casing to be connected and cuts off the inner guide plate bent upward by the inner guide block; F. Divers go into the water and evenly apply the Leak-proof King on both sides of the inner and outer joints of the steel casing to be connected and the underwater steel casing to complete further sealing.

2. The construction method for underwater docking of steel casing according to claim 1 is characterized in that: In step A, an inner guide plate is provided downward in the middle of the bottom of the inner guide block, and its width is smaller than that of the inner guide block. An outer guide plate is provided downward in the middle of the bottom of the outer guide block, and its width is smaller than that of the outer guide block.

3. The construction method for underwater docking of steel casings according to claim 2 is characterized in that: In step A, the bottom end of the lower opening of the steel casing to be extended is clamped between the middle parts of the inner guide block and the outer guide block.

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