CN-122013739-A - Offshore installation method for pile foundation jacket of ultra-large converter station

CN122013739ACN 122013739 ACN122013739 ACN 122013739ACN-122013739-A

Abstract

The invention provides an offshore installation method of a pile foundation jacket of an oversized converter station, and relates to the technical field of offshore heavy-duty structure installation. The method comprises the steps of taking a floating pontoon, a semi-submersible barge and a jacket in a pile foundation hoisting scene of an oversized convertor station as a core multi-floating-body system, establishing a 'hydrodynamic parameter-motion response-load distribution' linkage control logic by combining fine detection on the seabed and quantitative screening of sea condition windows and hydrodynamic interference analysis under a double-ship typical arrangement mode, and realizing cooperative matching of the submerged semi-submersible barge, the loading of the floating pontoon and the motion response of the multi-floating-body by depending on a multi-floating-body coupling hydrodynamic model, so that the technical problems of poor cooperation and high safety risk caused by neglecting the hydrodynamic interference of the multi-floating-body in the traditional installation method are solved, and the method is suitable for offshore installation operation of the pile foundation jacket of the oversized convertor station.

Inventors

WANG JINGFENG
CAO XIAOJI
LIN CHUANWEI
WANG YONGTIAN
SU MING
CAO FENGLI
CHEN XIAOXIANG
ZHU YAOJIE
SHI HAOJIE
ZHAO ZHIGE

Assignees

南通振华重型装备制造有限公司
中国电建集团福建省电力勘测设计院有限公司
上海振华重工(集团)股份有限公司

Dates

Publication Date: 20260512
Application Date: 20251219

Claims (10)

1. The marine installation method of the pile foundation jacket of the ultra-large converter station is characterized by comprising the following steps of, S1, sweeping the seabed of a jacket installation area, acquiring a response amplitude operator of a multi-floating body system by a frequency domain hydrodynamic force calculation method in combination with installation sea state statistical data of a sea area, and screening an adaptive operation window; s2, carrying an oversized converter station pile foundation jacket of a preassembled floating box to a construction sea area by a semi-submersible barge, and fixing a ship position by throwing a fixing anchor; S3, enabling the floating crane ship to enter a construction sea area, and realizing centering positioning with the semi-submersible barge to ensure span conditions required by hoisting operation; S4, a rigging and wind wave compensation device is hung between the floating crane vessel and the conduit frame, a collision protection assembly is installed, a multi-floating body monitoring device is deployed, and the relative position of the two vessels, the motion state of the floating bodies and the stress data of the slings are collected in real time; s5, unbinding the sea binding between the jacket and the semi-submersible barge, and detecting the tightness of the buoyancy tank and the coupling response baseline state of the multi-floating body system; S6, calculating the additional mass and the radiation damping of the double-ship system based on the frequency domain hydrodynamic model, deducing the structural buoyancy of the double-ship system by combining the water depth of the jacket, substituting the structural buoyancy into a load linkage logic formula, and cooperatively controlling the submergence of the semi-submersible barge and the hoisting load of the floating crane until the jacket is completely separated from the semi-submersible barge; and S7, lifting the jacket to the installation position by the floating crane, fine-adjusting the posture of the jacket through the posture adjusting assembly, and then removing the operation equipment after the jacket is fixed, wherein the coupling response control of the multi-floating body system is based on a double-ship coupling hydrodynamic model based on a face element method, so that the risk of motion amplification caused by the double-ship gap resonance phenomenon is avoided.
2. The method for installing a pile foundation jacket on a sea of an oversized converter station according to claim 1, wherein the logic formula in the step S6 is a semi-submersible real-time load = total weight of jacket and pontoon-total buoyancy of jacket-real-time sling weight of floating vessel.
3. The method for installing a jacket on the sea of a pile foundation of an oversized converter station according to claim 2, wherein the step S1 uses a multi-beam detection device to sweep the sea floor in the jacket installation area.
4. The method for installing the pile foundation jacket of the ultra-large type convertor station on the sea according to claim 3, wherein the operation window screening in the step S1 is combined with the stormy waves, the flow velocity characteristics and the motion threshold of the multi-floating body system of the installation sea area, and the condition of sea conditions which are easy to cause resonance is avoided by responding to the analysis of amplitude operator, so that the motion state of the floating body is ensured to meet the installation operation requirement.
5. The offshore installation method of pile foundation jacket of ultra-large converter station according to claim 4, wherein the floating pontoon and semi-submersible barge in step S3 are arranged in series or in a t-shape to realize centering.
6. The method of installing a pile jacket for an oversized converter station offshore according to claim 5, wherein the double vessel arrangement is selected based on hydrodynamic disturbance analysis, the series arrangement being for sea conditions with wave orientation coincident with the long axis of the hull, and the tee arrangement being for beam sea or oblique wave sea conditions.
7. The method for installing a pile foundation jacket of an oversized converter station on the sea according to claim 6, wherein the multi-floating body monitoring device in the step S4 comprises a GNSS positioner, a six-degree-of-freedom attitude sensor and a sling tension sensor, the device data update frequency is required to meet the real-time control requirement, the timely feedback of the relative motion state of the double vessels is ensured, and the adjustment mechanism is triggered when the relative motion amplitude exceeds the preset range.
8. The method for installing a jacket on a pile foundation of an oversized converter station according to claim 7, wherein the buoyancy of the jacket structure in the step S6 is obtained by combining the water depth of the jacket and the buoyancy characteristics of the jacket, the total buoyancy is the sum of the buoyancy of the structure and the buoyancy of the buoyancy tank, and the load linkage logic is required to synchronously correlate the influence of the additional mass and the radiation damping of the double ships on the load transfer.
9. The offshore installation method of the pile foundation jacket of the oversized converter station of claim 8, wherein the submerging speed of the semi-submersible barge and the loading speed of the floating pontoon in the step S6 are required to be dynamically adjusted based on the relative motion state of the double vessels, the submerging speed is controlled to be 0.3-0.5m/min, the loading speed is controlled to be 30-50t/min, and the stability of the multi-floating body system is ensured.
10. The method of marine installation of a super large converter station pile jacket according to claim 9, wherein said attitude adjustment assembly of step S7 comprises a level and an altimeter.

Description

Offshore installation method for pile foundation jacket of ultra-large converter station Technical Field The invention relates to the technical field of installation of offshore heavy structures, in particular to an offshore installation method of a pile foundation jacket of an oversized converter station. Background With the large-scale development of offshore flexible direct current transmission engineering, an ultra-large converter station pile foundation jacket is used as an engineering core bearing structure, and a plurality of floating bodies which depend on a floating crane and a semi-submersible barge are installed at sea to cooperatively operate. The existing jacket offshore installation technology has significant limitations. The hydrodynamic interference effect of the multiple floating bodies is ignored, the hydrodynamic calculation is carried out based on the isolated working condition of the single floating body in the prior art, and the wave-making interference and flow field interaction of the floating crane and the semi-submersible barge under serial connection or T-shaped arrangement are not considered. When the distance between the two vessels is 30-50m, the wave-making interference can lead the prediction error of the motion response of the single vessel to exceed 20%, but the interference is not quantized in the prior art, and the jacket collision or the abnormal stress of the sling is easily caused. Lack of coupled response and quantitative association of operation-the prior art mostly uses empirical operation to control the semi-submersible barge submergence and floating vessel loading, and does not establish a linkage mechanism of 'additional mass-radiation damping-motion response'. If the loading time is optimized without combining the pitching RAO peak value of the double-ship, the stress fluctuation of the sling exceeds 15%, and the mounting precision requirement of the pile foundation jacket of the ultra-large converter station cannot be met. The sea condition adaptation lacks theoretical support, the prior art screens the operation window by using a fixed wave height and a wind speed threshold value, and the logic of 'sea area actual measurement sea condition and multi-floating body RAO calculation' is not combined. If the influence of the difference of the constant wave direction and the strong wave direction of the installation sea area on the double-ship interference is not considered, the utilization rate of the operation window period is low, and the danger caused by gap resonance (wave number kL=npi) cannot be avoided. The load calculation is separated from hydrodynamic parameters, namely the load distribution in the prior art is simply reduced to total weight-buoyancy, and the influence of the additional mass of the double ship and the radiation damping on the load transfer is not associated. If the semi-submersible barge is submerged to the maximum depth, the additional mass change can cause the calculation deviation of the real-time load to be 100-200t, and the overload or the dip of the single ship load easily occurs. In conclusion, the technical problems of large cooperative difficulty and high safety risk caused by the motion interference of multiple floating bodies in the installation process of the ultra-large structure exist in the prior art. Disclosure of Invention The invention provides an offshore installation method of pile foundation jackets of an oversized convertor station, which aims to solve the problems, and achieves three core targets based on the coupling response characteristics of multiple floating bodies, namely, quantifying the coupling response of a floating crane, a semi-submersible barge, and a jacket multiple floating body system, defining the hydrodynamic interference law under the typical arrangement of double ships, establishing a hydrodynamic parameter-operation-load distribution linkage mechanism, improving the cooperative stability of the multiple floating bodies, optimizing sea condition screening based on the motion characteristics of the multiple floating bodies, and improving the suitability and installation safety of an operation window period. The invention provides a marine installation method of a pile foundation jacket of an oversized converter station, which mainly comprises the following steps: S1, scanning the seabed of a jacket installation area by adopting multi-beam detection equipment, acquiring a Response Amplitude Operator (RAO) of a multi-floating body system (comprising a floating crane, a semi-submersible vessel and a jacket) by a frequency domain hydrodynamic calculation method in combination with sea state statistical data of an installation sea area, and screening an adaptive operation window; s2, carrying an oversized converter station pile foundation jacket of a preassembled floating box to a construction sea area by a semi-submersible barge, and fixing a ship position by throwing a fixing anchor; S3, enabling the