CN106926989A - A kind of combined simple ocean platform and its construction method - Google Patents

Abstract

The invention discloses a kind of combined simple ocean platform and its construction method, including square steel framework, steel plate, piling bar and top job platform, top job platform is welded by four hollow pillar stands with landing slab, transverse direction is welded between four root posts, oblique strut forms space net rack system, the bottom sides of four root posts are by the symmetrical soldering sleeve of steel pipe, four piling bars are first set during construction, based on sleeve first square steel frame hub on four piling bars, bar hole is then based on to entangle on piling bar steel plate, again second square steel frame hub on four piling bars, then lifting top job platform entangles four piling bar blending bolts and fixes based on four sleeve pipes, ground is depressed into stable state using seawater weight, thus simple ocean platform is constituted.Carried offshore platform structure is simple, and construction weight is small, and foundation's bottom area is big, and preconsolidation is carried out to ground using seawater weight, adapts to mud, the construction environment of intertidal zone, economical and practicality.

Description

A combined simple offshore platform and its construction method

Technical field:

The invention relates to an offshore platform structure, in particular to a combined simple offshore platform and a construction method thereof.

Background technique:

my country's marine tidal flats and intertidal zone are rich in land resources, which are characterized by large area, concentrated distribution, good location conditions, and great potential for comprehensive development of agriculture, animal husbandry and fishery. The intertidal zone is an important base for aquaculture and the development of agricultural production, and a valuable asset for developing the ocean and marine industry.

Generally, simple offshore platforms need to be built in tidal flats and intertidal zones for marine operations. The soil layer in tidal flats and intertidal zones is soft and the bearing capacity is low, and the intertidal zone is affected by tidal fluctuations, the duration of high water levels in a day is short, and the water level height is limited, so the construction environment is poor.

Generally, pile foundation or barrel foundation can be used as the foundation type of the simple offshore platform in the intertidal zone. However, if the length and weight of the pile foundation are large, large-scale lifting and piling equipment are required, but the water level in the intertidal zone cannot be used by large construction ships; Under the action of pressure difference, it is difficult for the barrel foundation to penetrate the seabed to the design depth. It can be seen that designing a foundation type suitable for the construction environment in tidal flats and intertidal zones is one of the key technologies for simple offshore platforms in silt areas.

Although tidal flats and intertidal zones are mostly silt and silty soils with low bearing capacity, if the area of the foundation is large enough, it is even possible to assemble the foundation with multiple steel plates and pre-compress the silt to a certain extent. It can make the offshore platform meet the deformation and stability requirements. It can be seen that it is necessary to explore the structure type and construction method of simple offshore platforms suitable for silt areas, and promote the innovation and progress of existing technologies.

Invention content:

In order to make up for the deficiencies of the existing technical problems, the object of the present invention is to provide a combined simple offshore platform and its construction method, which adopts the foundation form of a combination of piles and steel plates, and uses the weight of seawater for pre-compression settlement, and the construction is simple.

Technical scheme of the present invention is as follows:

The combined simple offshore platform is characterized in that it includes two square steel frames, steel plates, steel piles and the upper working platform, and four steel piles are driven vertically in the sea area specified in the design, and the four steel piles are sequentially inserted into the first A square steel frame, steel plates, a second square steel frame, the upper ends of four steel piles protrude from the second square steel frame and an upper working platform is installed.

The combined simple offshore platform is characterized in that the square steel frame is welded in a grid shape by a plurality of vertical square steels criss-crossed, and the whole is in a square shape, and four sides are welded symmetrically and uniformly inside it. There are two sleeves, and the connecting lines of the four sleeves are also in a square shape, and the two diagonally positioned sleeves are also connected by oblique welding with square steel.

The combined simple offshore platform is characterized in that the upper working platform is composed of four uprights welded to the platform plate, and the four uprights are distributed at four inflection points of a square and vertically erected, and the adjacent two of the four uprights are Horizontal and oblique struts are welded between them to form a space grid system. The bottom of the four columns is welded with a mouth-shaped expansion plate. The bottom side of each column is symmetrically welded with a sleeve through steel pipes. The side wall of the sleeve is welded and fixed to the expansion plate. .

The combined simple offshore platform is characterized in that the center distance of the four casings on the upper working platform is equal to the center distance of the four casings on the square steel frame, and the inner diameter of the casing is equal to the inner diameter of the casing. The inner diameter of the pipe is 1~2cm larger than the outer diameter of the steel pile.

The combined simple offshore platform is characterized in that there are two steel plates, and the two plates are relatively arranged between the first square steel frame and the second square steel frame, and the width of the strip hole on the steel plate is slightly Greater than the outer diameter of the steel pile, the length of the strip hole is more than three times the outer diameter of the steel pile, and the center distance between the two strip holes on each steel plate is equal to the center distance between two adjacent sleeves on the square steel frame.

A construction method for a combined simple offshore platform is characterized in that it comprises the following steps:

1) Drive in four steel piles:

According to the design parameters, drive four steel piles vertically in the sea area specified by the design, and finally make the parameters such as the center distance, plumbness, and soil penetration depth of the four steel piles meet the design requirements;

2) Leveling the seabed:

Level the seabed around the four steel piles that is larger than the outer contour of the square steel frame, so that the maximum height difference of the seabed soil within the leveling range is less than 10cm;

3) The first square steel frame covers the steel pile:

Lift the first square steel frame so that the four sleeves on the square steel frame cover the corresponding four steel piles and sink until it touches the seabed;

4), the steel plate covers the steel pile:

Lift the two steel plates one by one, so that the two strip holes on the steel plates cover the two adjacent steel piles to sink and press on the first square steel frame;

5) The second square steel frame covers the steel pile:

Lift the second square steel frame so that the four sleeves on the square steel frame cover the corresponding four steel piles to sink and press on the steel plate;

6) Connect the upper working platform:

Lift the upper working platform and sink it to the position of the pile foundation, make the four casings of the upper working platform cover the four steel piles, sink and press on the second square steel frame, and fix the bolt holes on the steel piles with bolts , to realize the interconnection between the upper working platform and the steel pile;

7) Water tank preloaded offshore platform:

The water tanks are evenly and symmetrically placed on the platform of the upper working platform, and the water tanks are gradually and symmetrically filled with seawater pumped by water pumps, so that the offshore platform compresses the seabed along the steel piles to a stable state under the gravity of the water tanks;

8) Remove the water tank and complete the construction:

After the preloading of the seabed soil at the bottom of the offshore platform meets the design requirements and the offshore platform reaches a stable state, the water tank is gradually and symmetrically removed, and the simple offshore platform is subjected to necessary inspection and verification, and the construction of the simple offshore platform is finally completed.

The beneficial effects of the present invention are:

1. The components of the present invention are independent of each other. This method of breaking them into parts makes the weight of each individual component smaller, reduces the requirements for transportation, lifting and other construction equipment for offshore operations, and is suitable for mud, intertidal zones construction environment;

2. The connection method between the components of the present invention is simple, without complicated connection methods and construction requirements. If it needs to be disassembled in the future, the removal can be completed according to the opposite steps of the installation method. The operation is simple and the construction is convenient;

3. The invention is composed of a square steel frame and a steel plate. Its contact area with the seabed soil is very large, which can reach more than twice the area of the platform plate. It can adapt to the geological conditions of the muddy seabed, and is simple to manufacture and convenient to construct. , is a simple, practical and economical design;

4. During the construction process of the present invention, a series of water tanks are placed on the platform plate and filled with seawater, and the foundation soil of the offshore platform is pre-compressed and consolidated by using the weight of seawater, so that the strength and post-construction settlement of the foundation soil meet the use requirements. It is economical, practical and rational to use the offshore platform structure itself for seabed foundation treatment.

Description of drawings:

Fig. 1 is a schematic diagram of the square steel frame structure of the present invention.

Fig. 2 is a structural schematic diagram of the stressed steel plate of the present invention.

Fig. 3 is a top view of the upper working platform of the present invention.

Fig. 4 is a bottom view of the upper working platform of the present invention.

Fig. 5 is a schematic diagram of four steel piles of the present invention after construction.

Fig. 6 is a schematic diagram of the first square steel frame inserted into steel piles according to the present invention.

Fig. 7 is a schematic diagram of a steel pile inserted into a stressed steel sheet according to the present invention.

Fig. 8 is a schematic diagram of a second square steel frame inserted into a steel pile according to the present invention.

Fig. 9 is a schematic diagram of the upper working platform inserted into the steel pile according to the present invention.

Fig. 10 is a schematic diagram of the water tank auxiliary ocean platform pressed into the seabed according to the present invention.

Fig. 11 is a three-dimensional schematic diagram of the constructed offshore platform of the present invention.

Fig. 12 is a front view of the offshore platform of the present invention after construction.

Explanation of reference signs: 1. Square steel frame; 2. Sleeve; 3. Steel plate; 4. Strip hole; 5. Column; 6. Platform plate; 7. Sleeve; 10. Conical pile tip; 11. Bolt hole; 12. Bolt; 13. Water tank; A, sea level; B, seabed surface; C, compression settlement.

detailed description:

See attached picture:

A combined simple offshore platform, including a square steel frame 1, steel plates 3, steel piles 9 and an upper operating platform, the upper operating platform is welded by four hollow columns 5 and a platform plate 6, and the four columns 5 are welded with Horizontal and oblique struts form a space grid system. The bottom sides of the four columns 5 pass through the symmetrical welded sleeves 7 of steel pipes. During construction, four steel piles 9 are first laid, and the first square steel The frame 1 is set on the four steel piles 9, and then the steel plate 3 is put on the four steel piles 9 based on the strip hole 4 and pressed on the first square steel frame 1, and then the second square steel is put on the second square steel frame based on the sleeve 2 The frame 1 is set on four steel piles 9 and pressed on the steel plate 3, and then the upper work platform is lifted based on the four casings 7 to cover the four steel piles 9, pressed on the second square steel frame 1 and fixed with bolts, using seawater The weight presses the seabed foundation to a stable state, thereby forming a simple ocean platform.

The square steel frame 1 is welded by multiple square steels perpendicular to each other, and has a square shape as a whole. Four sleeves 2 are welded symmetrically and evenly inside it. Square steel is also used for oblique welding connection between the sleeves 2 at the diagonal positions, as shown in FIG. 1 .

The upper and lower surfaces of the square steel frame 1 are planes, which can be in close contact with the steel plate 3 . The proposed simple offshore platform uses two square steel frames 1 in total, and a steel plate 3 is added between the two square steel frames 1 to form a foundation floor, and the load of the offshore platform is transmitted to the seabed through the steel plates 3 . The square steel frame 1 plays the role of restraint and control on the steel plate 3. The upper load is evenly transmitted to the steel plate 3 through the square steel frame 1. The square steel frame 1 makes the stress on the steel plate 3 basically uniform everywhere, and plays the role of load diffusion.

Because the bearing capacity of silt and silty soil is low, the size of the square steel frame 1 and the steel plate 3 can be increased to achieve the purpose of increasing the base area. Generally, the area of the square steel frame 1 can reach more than twice the area of the platform plate 6 . The foundation form formed by the combination of the square steel frame 1 and the steel plate 3 has a very large contact area with the seabed soil, can adapt to the geological conditions of the muddy seabed, and is simple to manufacture and convenient to construct. It is a simple and practical design scheme.

The upper working platform is welded by four uprights 5 and platform plate 6, the four uprights 5 form a square shape, the four uprights 5 are welded with horizontal and oblique struts to form a space grid system, the four uprights 5 The bottom is welded with a closed mouth-shaped expansion plate 8, and the bottom side of each column 5 passes through a steel pipe symmetrical welding sleeve 7, as shown in Figures 3 and 4.

A circle of expansion plates 8 is set on the upper work platform to increase the contact area between the upper work platform and the square steel frame 1, so that the upper load can be effectively spread to the steel plate 3 through the square steel frame 1, and avoid excessive deformation due to stress concentration .

The distance between the central axes of the four sleeves 7 on the upper working platform is equal to the distance between the central axes of the four sleeves 2 on the square steel frame 1, and the hollow inner diameter of the sleeves 7 is equal to the hollow inner diameter of the sleeve 2. Finally, the four sleeves 7 and the four sleeves 2 are all sleeved on the steel pile 9, so the positional relationship between the sleeves 7 and the sleeves 2 must be consistent.

The inner diameter of the casing 7 is 1-2 cm greater than the outer diameter of the steel pile 9, the width of the strip hole 4 on the steel plate 3 is slightly greater than the outer diameter of the steel pile 9, and the length of the strip hole 4 is more than three times greater than the outer diameter of the steel pile 9, The distance between the center points of two bar-shaped holes 4 on the steel plate 3 is equal to the distance between the central axes of two adjacent sleeves 2 on the square steel frame 1 .

A steel plate 3 is provided with two strip holes 4, and the two steel plates 3 can be assembled to cover the square steel frame 1, as shown in FIG. 7 . The length of the strip hole 4 is more than three times greater than the outer diameter of the steel pile 9, so that the steel plate 3 is sleeved on the steel pile 9 for convenience.

When the verticality of the four steel piles 9 meets the requirements, the square steel frame 1 and the steel plate 3 are set behind the steel piles 9, and they can only settle vertically downward along the steel piles 9, but not in the horizontal direction. displacement. That is, the steel pile 9 plays the role of positioning, restraint and control on the other steel frame 1 and the steel plate 3, and the steel pile 9 itself does not bear the vertical load of the offshore platform. Therefore, the cross-sectional size of the steel pile 9 does not need to be too large, as long as it can be driven into a compact soil layer and maintain stability under external loads.

The horizontal load on the offshore platform is jointly borne by the structural system composed of four steel piles 9, square steel frame 1 and steel plate 3, so the steel pile 9 must have sufficient depth to maintain its vertical degree and stability.

The steel pile 9, the square steel frame 1, and the upper working platform are all welded by steel. The strength of each component, weld and the overall structure should meet the combined load requirements under complex working conditions without yielding, and each component should meet the stress Concentration is required without excessive deformation beyond that permitted by the specification.

A construction method for a combined simple offshore platform is characterized in that it comprises the following steps:

1) Drive in four steel piles:

According to the design parameters, four steel piles 9 are driven vertically in the sea area specified by the design, and finally the parameters such as the center distance, plumbness, and soil penetration depth of the four steel piles 9 meet the design requirements, as shown in Fig. 5 .

The distance between the central axes of the four steel piles 9, the distance between the central axes of the four casings 7, and the distance between the central axes of the four sleeves 2 on the square steel frame 1 are all equal, that is, the square steel frame 1 is based on The four sleeves 2 can be sleeved on the four steel piles 9 and slide into the seabed, and the upper working platform can be sleeved on the four steel piles 9 and slide into the seabed based on the sleeves 7 .

2) Leveling the seabed:

Leveling the seabed around the four steel piles 9 that is larger than the outer contour of the square steel frame 1, so that the maximum height difference of the seabed soil within the leveling range is less than 10cm.

Subsequent square steel frame 1 and steel plate 3 are set on the four steel piles 9 to contact the seabed. If the surface of the seabed is uneven and the height difference is too large, the sinking of the steel plate 3 will cause inclination and torsion. Therefore, leveling the seabed is conducive to improving the stability of the offshore platform.

3) The first square steel frame covers the steel pile:

The first square steel frame 1 is hoisted so that the four sleeves 2 on the square steel frame 1 cover the corresponding four steel piles 9 and sink until they touch the seabed, as shown in Figure 6 .

Since the sleeve 2 has a certain length, it sinks along the steel pile 9. When the plumbness of the steel pile 9 meets the requirements, it can only settle vertically without horizontal displacement.

The function of the first square steel frame 1 is to restrain and control the uniform settlement of the steel plate 3 above it, and maintain the steel plate 3 in a horizontal state after being loaded.

4), the steel plate covers the steel pile:

Lift the two steel plates 3 one by one, so that the two strip holes 4 on the steel plates 3 cover the two adjacent steel piles 9 to sink and press on the first square steel frame 1, as shown in Figure 7 .

The combined area of the two steel plates 3 is the outer contour area of the square steel frame 1 . The role of the steel plate 3 is to transmit the upper load of the offshore platform to the larger area of seabed soil. Since the area of the steel plate 3 can take a larger value, the base pressure of the seabed soil at the bottom of the steel plate 3 is relatively small, which is suitable for the characteristics of low strength and high compressibility of the seabed soil such as silt and silty soil.

5) The second square steel frame covers the steel pile:

Lift the second square steel frame 1 so that the four sleeves 2 on the square steel frame 1 cover the corresponding four steel piles 9 to sink and press on the steel plate 3, as shown in FIG. 8 .

The function of the second square steel frame 1 is to effectively and evenly transmit the load on the offshore platform to the steel plate 3, so as to avoid uneven deformation of the steel plate 3 due to excessive local stress.

6) Connect the upper working platform:

Lift the upper working platform and sink it to the position of the pile foundation, make the four casings 7 of the upper working platform cover the four steel piles 9, sink and press on the second square steel frame 1, and fix the steel piles 9 with bolts Bolt holes on the upper part realize the mutual connection between the upper working platform and the steel piles, as shown in Figure 9.

The expansion plate 8 of the upper working platform is in close contact with the square steel frame 1 directly below. Since the square steel frame 1 has sufficient strength and rigidity, it can effectively and evenly transfer the load transmitted by the expansion plate 8 to the lower one. The steel plate 3 realizes the effective diffusion of stress.

Under the subsequent use load, the upper work platform is pressed on the square steel frame, so the bolts in the bolt holes on the steel pile 9 only play a role of bolting, preventing the separation and separation between the upper work platform and the steel pile 9 under special circumstances. fall off. The horizontal load on the upper working platform will be transmitted to the steel pile 9 through the casing 7, so the casing 7 should have sufficient strength and stiffness to withstand the combined load under complex working conditions without buckling and deformation.

When the verticality of the four steel piles 9 meets the requirements, the square steel frame 1, the steel plate 3 and the upper working platform vertically compress the seabed soil along the four steel piles 9, so that the square steel frame 1, the steel plate 3 and the The upper work platform can only undergo vertical settlement without horizontal displacement, and the steel pile 9 plays the role of guiding, restraining and controlling the square steel frame 1, the steel plate 3 and the upper work platform. The vertical load is transmitted to the seabed by the steel plate 3, and the steel pile 9 itself does not bear the vertical load.

7) Water tank preloaded offshore platform:

Place water tanks 13 evenly and symmetrically on the platform plate 6 of the upper working platform, and pump seawater to fill each water tank 13 gradually and symmetrically, so that the offshore platform compresses the seabed along the steel pile 9 to a stable state under the gravity of the water tank.

The density of seawater is generally 1.025g/cm ³ , that is, 1m ³ of seawater weighs about 1 ton. If a large number of water tanks are accumulatively filled to 10m ³ , a vertical load of 10t can be applied to the seabed soil; if the accumulative water tanks are filled with water of 15m ³ , a vertical load of 15t can be applied to the seabed soil; If the water tank is accumulatively filled with 20m ³ of water, a vertical load of 20t can be applied to the seabed soil. The water tank is generally made of plastic, its cost is low, and it can be used repeatedly. It can be seen that pumping seawater according to local conditions to preload and consolidate seabed soil is a cheap and efficient construction method. In particular, during the loading process, the total weight of the water tank can exceed the subsequent use load, so that vertical settlement will no longer occur during the subsequent use of the offshore platform, and the overall stability of the offshore platform will be improved.

The filling of the water tank should be carried out symmetrically and evenly along the central axis of the platform plate 6 to avoid uneven loads. And the water tank itself should have sufficient strength. When multi-layer water tanks are stacked, the bottom water tank should be able to bear the upper load without damage.

The overall weight of the water tank should be gradually and slowly increased, and the loading and loading time of each level should be reasonably designed so that the seabed soil is gradually compressed and consolidated during the slow loading process from small to large. The sinking attitude of the upper working platform should be observed and checked at all times to ensure the verticality of the sinking of the upper working platform. If the upper working platform is tilted to a certain extent, more water tanks can be added in the opposite direction of the tilt, and the bending moment formed by uneven loading can correct the tilted offshore platform, so as to ensure that the verticality of the offshore platform meets the requirements.

During the construction process, the water tank at the bottom should be prevented from being soaked in seawater. If the water tank is immersed in seawater, it will be subjected to upward buoyancy, which offsets the weight of the water tank, which is obviously unfavorable for pre-compression consolidation.

The final loading load, that is, the total weight of the water tank can exceed the subsequent use load of the offshore platform, causing the offshore platform to generate a large compression settlement C, as shown in Figure 12, which can prevent the vertical settlement of the offshore platform from occurring during use. Improve the overall stability of the offshore platform. It can be seen that pumping seawater according to local conditions to apply vertical loads to offshore platforms is a cheap and efficient construction method.

8) Remove the water tank and complete the construction:

After the preloading of the seabed soil at the bottom of the offshore platform meets the design requirements and the offshore platform reaches a stable state, the water tank 13 is gradually and symmetrically removed, and necessary inspections and verifications are carried out on the simple offshore platform, and the construction of the simple offshore platform is finally completed.

In the process of removing the water tank, the uniformity and symmetry of the load on the remaining water tank should be maintained, and uneven load should not be generated, and the offshore platform should not be tilted and shifted.

The present invention is not limited to the above-mentioned specific implementation methods. According to the above-mentioned content, according to the common technical knowledge and conventional means in this field, without departing from the above-mentioned basic technical idea of the present invention, the present invention can also make other equivalents in various forms. Modifications, substitutions or alterations all fall within the protection scope of the present invention.

Claims (6)

1. a kind of combined simple ocean platform, it is characterised in that including two square steel frameworks, steel plate, piling bar and top operation Platform and the marine site specified of design it is vertical squeeze into four piling bars, first square steel framework, steel are inserted on four piling bars successively Plate, second square steel framework, four piling bar upper ends stretch out second square steel framework and are provided with top job platform.

2. combined simple ocean platform according to claim 1, it is characterised in that described square steel framework is by mutually hanging down Crisscross latticed, the overall square shape that is welded of many straight square steel, in its internal symmetry, uniformly welds four Individual sleeve, four sleeve lines also square shape, also oblique welding is carried out between two sleeves of diagonal position with square steel Connection.

3. combined simple ocean platform according to claim 1, it is characterised in that described top job platform is by four Root post is formed by welding with landing slab, and four root posts are distributed in four flex points of square and longitudinally erect, adjacent two in four root posts Horizontal, oblique strut Special composition rack system is welded between root, the bottom welding of four root posts has the expansion board of hollow, Each column bottom side is symmetrically welded with sleeve pipe by steel pipe, and sleeve side walls are welded and fixed with expansion board.

4. combined simple ocean platform according to claim 1, it is characterised in that four on described top job platform Individual cannula center is away from away from equal, casing inner diameter is equal with the internal diameter of sleeve, casing inner diameter with four bushing cores on square steel framework More than 1 ~ 2cm of piling bar external diameter.

5. combined simple ocean platform according to claim 1, it is characterised in that described steel plate has two pieces, two pieces It is oppositely arranged and is laid between first square steel framework and second square steel framework, bar shaped hole width is slightly larger than outside piling bar on steel plate Footpath, bar shaped hole length is more than more than the three times of piling bar external diameter, two bar hole centre-to-centre spacing and phase on square steel framework on every block of steel plate Adjacent two bushing cores are away from equal.

6. a kind of construction method of combined simple ocean platform, it is characterised in that comprise the following steps：

1）, squeeze into four piling bars：

According to design parameter, the marine site specified in design it is vertical squeeze into four piling bars, finally make four centre-to-centre spacing of piling bar, lead The parameters such as sag, embedded depth meet design requirement；

2）, smooth sea bed：

Four piling bar peripheries are carried out more than the sea bed in the range of square steel framework outline smooth, make the seabed soil in smooth scope The body maximum discrepancy in elevation is less than 10cm；

3）, first square steel framework entangle piling bar：

First square steel framework of lifting, makes on square steel framework four sleeves entangle corresponding four piling bars and sink until contact Sea bed；

4）, steel plate entangle piling bar：

Lift by crane two blocks of steel plates one by one successively, on steel plate two bar holes is entangled two adjacent piling bars and sink and be pressed in first On individual square steel framework；

5）, second square steel framework entangle piling bar：

Second square steel framework of lifting, makes on square steel framework four sleeves entangle corresponding four piling bars and sinks and be pressed in steel plate On；

6）, connection top job platform：

Lifting top job platform is simultaneously sunk down at pile foundation position, four sleeve pipes of top job platform is entangled four piling bars Sink and be pressed on second square steel framework, the bolt hole that blending bolt is fixed on piling bar realizes top job platform and piling bar Between interconnection；

7）, water tank precompressed ocean platform：

Uniform, symmetrical placement water tank on the landing slab of top job platform, is filled up with water pump extracting seawater is progressively symmetrical Each water tank, makes ocean platform compress sea bed to stable state along piling bar under water tank Action of Gravity Field；

8）, remove water tank, complete construction：

The seabed soil precompressed of ocean platform bottom meets design requirement and after ocean platform reaches stable state, progressively symmetrical Water tank is removed, and necessary detection and verification are carried out to simple ocean platform, be finally completed the construction of simple ocean platform.