59 results about "Tidal range" patented technology

The invention provides a reservoir pressure salinity scheduling method based on a physical information neural network (PINN). The reservoir pressure salinity scheduling method comprises the following steps: Step 1, salinity prediction based on a physical information neural network (PINN) model; the method comprises the following steps: in a PINN model framework, embedding a physical law of salinity conservation into a multi-layer perceptron (MLP) artificial neural network for training so as to carry out salinity prediction; step 2, establishing an estuary water-salt model based on a three-dimensional ocean numerical FVCOM model; step 3, carrying out upstream reservoir salty water pressing and light water supplementing emergency scheduling based on salinity forecast; comprising the following steps: Step3.1, establishing a multi-objective function; and Step3.2, solving a scheduling model. According to the method, the salinity momentum conservation constraint can be considered, the salinity prediction accuracy under the influence of different upstream flows and downstream tidal ranges can be improved, and the emergency scheduling of the reservoir for the salt tide invasion of the estuary drinking water source can be carried out in combination with the scheduling model, so that the water supply safety is ensured.

The invention provides a floating photovoltaic split mooring platform, and belongs to the technical field of ocean engineering. The platform mainly comprises at least one floating body, and the floating body is provided with a first floating frame and a second floating frame. Wherein a photovoltaic panel is mounted on the first floating frame; the first floating frame is in sliding connection with the second floating frame, and a damper is arranged between the first floating frame and the second floating frame; and the second floating frame is connected with the berth. The floating body is designed to be of a split type structure, through sliding connection, heaving displacement generated by tide level changes is absorbed by the first floating frame in a self-adaptive mode, the stress state of the second floating frame is not obviously changed, tidal range input is prevented from directly acting on the whole, then forced coupling of the tidal range to the mooring system is weakened, and the mooring effect is improved. The mooring peak tension and the cyclic fatigue risk are obviously reduced; furthermore, the second floating frame can be moored and deloaded through the split design, safety protection is enhanced, and the safety, reliability and applicability of the platform in a large-tidal-range shallow sea area are remarkably improved.

The invention relates to the technical field of breakwaters, in particular to a breakwater embedded with an oscillating water column type wave energy power generation device adapting to tidal range variation, which comprises a breakwater body, a plurality of mounting grooves are formed in the head wave surface of the breakwater body and are respectively arranged at intervals in the horizontal direction, and a driving system is arranged in each mounting groove. The driving system is connected with an oscillating water column type wave energy power generation device, and the oscillating water column type wave energy power generation device is driven by the driving system to ascend and descend in the vertical direction. A plurality of oscillating water column type wave energy power generation devices are embedded in the head wave face of the breakwater body at intervals, and the heights and opening orientations of the oscillating water column type wave energy power generation devices are flexibly adjusted through the driving system so as to adapt to and be matched with tidal range changes and incoming wave direction changes of a service sea area; on the basis of maintaining stable mooring conditions in the harbor, energy absorption and capture of waves with different tide levels and incoming wave directions are achieved in an efficient mode, and the capture efficiency is improved to the maximum extent.

The invention provides a tidal reach water level prediction method, device, equipment and medium, and the prediction method comprises the following steps: collecting historical data and current time period data, the historical data and the current time period data comprising actually measured runoff data, actually measured water level data and actually measured tidal range data; lagging adjustment is conducted on the actually measured runoff data and the actually measured tidal range data with the actually measured water level data as the benchmark through a cross-correlation analysis method; performing EEMD decomposition to obtain respective intrinsic mode functions and residual errors; and outputting the eigenmode function of the water level data of the analysis station in the future time period and the predicted value of the residual error through the LSTM model, and carrying out superposition to obtain the predicted value of the water level of the tidal reach. According to the method, the water level data, the runoff data and the tidal range data of the tidal reach are subjected to conjoint analysis, the problems of nonlinear signal processing and low precision of the water level of the tidal reach are effectively solved through EEMD decomposition and the LSTM model, and the prediction accuracy of the water level of the tidal reach is greatly improved.

The invention provides a device for ice load measurement and ice-induced vibration suppression and an ocean structure. The device for ice load measurement and ice-induced vibration suppression is characterized by comprising a fixed strut beam structure (2) which is arranged on the outer surface of an upright or nearly upright ocean structure and is axially parallel to the ocean structure, and a steel plate (1) covering the range of a tidal range zone is arranged on the outer side of the strut beam structure (2) in a sleeving mode. And a stress measuring device (3) is mounted on the inner side of the strut beam structure (2). The fixed strut beams and the steel plates are installed on the outer surface of the ocean structure, the contact form of sea ice and the structure is changed, the crushing mechanism of the sea ice is disturbed, the energy of the sea ice is absorbed, the vibration amplitude is reduced, meanwhile, real-time monitoring of the ice load is achieved, frequency locking vibration is eliminated, and the safety and stability of the structure are ensured.

The invention provides an ice-thorn-resistant structure, and relates to the technical field of offshore wind power ice-resistant structures, the ice-thorn-resistant structure comprises a pile column mechanism, a cage sleeve mechanism, a driving mechanism and a plurality of ice-thorn mechanisms, the cage sleeve mechanism is slidably connected with the pile column mechanism, and the cage sleeve mechanism is sequentially provided with the plurality of ice-thorn mechanisms in the circumferential direction of the cage sleeve mechanism; the driving mechanism is connected with the pile column mechanism and the cage sleeve mechanism, and the driving mechanism is used for driving the cage sleeve mechanism and the multiple ice thorn mechanisms to move in the extending direction of the pile column mechanism. The technical problems that in the prior art, an existing ice-resistant structure is large in weight, complex to mount and dismount and incapable of adapting to tidal range changes are solved.

The present application relates to the technical field of material performance testing, and discloses a material corrosion testing device and testing method for simulating ocean acidification environment, comprising: a closed simulation testing cabin, which is internally divided into a top-down salt mist simulation cabin, a wet heat simulation cabin and a high-pressure immersion simulation cabin by horizontally arranging openable and closable upper and lower insulation boards, and is provided with a cabin door with a sealing structure at the top; through the independent modular design of the salt mist simulation cabin, the wet heat simulation cabin and the high-pressure immersion simulation cabin, and the automatic switching function of the rotatable lifting sample holder, the present device realizes precise coupling and seamless switching of corrosion environments such as salt mist spraying, high temperature and high humidity, and deep sea high pressure, and the sample can complete the whole cycle corrosion behavior research of the marine atmospheric zone, the splash zone, the tidal zone and the full immersion zone on the same platform, and eliminates the interface effect caused by the traditional multiple equipment series connection testing.

The invention discloses an efficient dredging device in an underwater limited space and a construction method of the efficient dredging device, and belongs to the technical field of underwater sludge cleaning. The desilting device comprises a vertical steel frame, a horizontal cross arm, RTK measuring equipment, a bottom device, a water suction opening, a flushing opening, a balancing weight, a molten steel pipe, a transparent rubber steel wire hose and a foam buoy. Wherein the vertical steel frame is horizontally welded with the horizontal cross brace; the bottom device is welded to the bottom of the vertical steel frame, a water suction opening is formed in the top of the bottom device, and a water suction opening and a water outlet are correspondingly formed in the bottom. According to the method, channel steel, steel pipes, steel plates, slurry pumps, RTK measuring equipment and other conventional materials and equipment are adopted, the desilting construction conditions of the underwater limited space can be met, construction is not affected by tide fluctuation, wind power and other natural factors, the construction period can be shortened, the underwater desilting quality can be guaranteed, an original revetment cannot be damaged in the construction process, and the construction period is shortened. And the overall construction cost is greatly reduced.

This invention relates to a self-buoyant gravity-driven positioning pile and a stake-type aquaculture cage, comprising a pile body, a pile tip fixed at the bottom end of the pile body, a pile lifting eye plate fixed at the top end of the pile body, and three watertight baffles arranged vertically within the pile body. This self-buoyant gravity-driven positioning pile and stake-type aquaculture cage features a simple and low-cost pile construction. It utilizes the cage's own buoyancy to achieve autonomous pile driving and lifting, which is significantly cheaper than traditional methods using lifting systems. Therefore, it greatly reduces the cost of the aquaculture cage. The cage is easy to operate, freely lifting and lowering using its own ballast system to assist in fish harvesting, maintenance, adapting to tidal changes, and providing full-submersion typhoon resistance. Through the balance between its own buoyancy and gravity, and with the adjustment of the float's weight and the ballast system, it achieves pile driving, lifting, and float raising / lowering operations, greatly reducing construction and operating costs.

The invention provides a method for quantifying tidal non-stationarity, and belongs to the technical field of natural science research based on nonlinear data analysis. Firstly, hour-by-hour tide observation data with the observation duration not less than one month in a target sea area are obtained; separating non-tidal low-frequency and high-frequency tidal changes in the data by using an empirical mode decomposition method, and extracting a tidal component; returning the tide component through a classical harmonic analysis CHA model to obtain CHA return tide; then calculating a correlation coefficient, a mean absolute error and a root-mean-square error of the tidal component and the CHA, and respectively dividing the mean absolute error and the root-mean-square error by an average value of the observation absolute values to obtain a normalized index; finally, (1, 0, 0) is used as a reference point, (CC, NMAE, NRMSE) is used as an observation point, and the tidal non-stationarity index NS is calculated according to a two-point distance formula. The device can be widely applied to global sea areas and is suitable for sea areas of different tide types and sea areas of different tidal ranges.

The application discloses a kind of tidal river network sluice operation data model processing method, system and terminal, it is related to sluice operation analysis technical field, and its technical scheme main points are: initial outer river tidal level is carried out noise reduction pretreatment, and sliding average is carried out;Select the smooth result of the highest matching degree of rising and falling tide trend, and carry out abnormal fluctuation elimination processing;The rising and falling tide trend in standard smooth result is analyzed;Rising and falling tide trend result and water level difference threshold are loaded in Infoworks RTC module;Different water level difference threshold is tried, and the optimal water level difference threshold of sluice opening and closing is determined, to obtain final Infoworks RTC module.The application is carried out to the smooth processing of outer river tidal level data, and the outer river tidal drop process is judged, according to the inner and outer river tidal difference to control the opening and closing of sluice, reach water quality model operation working condition and actual engineering working condition consistent, provide strong support for later water power water quality model rating.

The application provides an anti-ice self-climbing floating offshore photovoltaic structure, which comprises a floating structure unit and a photovoltaic array arranged above the floating structure unit; the floating structure unit comprises a floating foundation and a truss structure, and an anchoring system flexibly connecting the floating structure unit and a mud surface of the seabed; a supporting leg part is arranged at the bottom of the truss structure, and the supporting leg part is connected with the upper part of the floating foundation, so that an external part surrounded by the floating foundation forms an anti-ice space, and the cross-sectional area of the top of the floating foundation is larger than the cross-sectional area of the bottom submerged in the sea; the floating offshore photovoltaic structure provided by the application has the characteristics of strong anti-wind and anti-wave and anti-ice capabilities in severe sea conditions, and has the bottom sitting capability, so as to be suitable for shallow water areas with large tidal range and easy beach sitting, improve the reliability of the structure, ensure the stability of the structure movement, and further reduce the risk.

A concave hermetic air / brine encapsulating vessel, or cap 10, positioned in the sea at a chosen area according to tidal range. Wherein the open underside of the vessel allows brine / sea water to freely enter or exit the vessel and the tide rises and falls respectively. This rise and fall of the brine within the vessel will result in changes to the air pressure within the vessel, as the air because pressurised as the brine rises, and forms a vacuum with the vessel as the brine falls. These changes in pressure are used to operate a pneumatic actuator 60, via a suitable system of valves 50,52 coupled to the inlets and / or outlets of a pipe couple to a vent 30 on the upper portion of the vessel, or within a plurality of pipes couple to a manifold 40 coupled to the vent 30. Wherein the operation of the pneumatic actuator 60 powers a generator 62 for producing and storing power.

The purpose of the present invention is to provide a wave power generation device capable of dealing with tidal fluctuations. That is, the present invention comprises: a foundation structure (10) that is installed upright on the seabed and has a pile member driven therein; leveling structures (20A, 20B) that are installed on the foundation structure (10) and are adjusted in height in response to changes in sea level caused by tidal fluctuations; and a seawater guide pipe (30) which is installed on the leveling structures (20A, 20B) and has an inclined flow path (31) having one end submerged in seawater and the other end exposed outside the surface of the seawater, and which drives a wave power generator (100) by collectively utilizing the longitudinal and transverse wave energy of seawater moving at an inclined angle along the inclined flow path (31). The wave power generation device has an improved structure in which the height of the seawater guide pipe changes in response to changes in sea level, and thus can uniformly sustain wave power generation even in environments with significant tidal fluctuations.

This invention relates to a smart forecasting method for saltwater intrusion in the Yangtze River Estuary based on multi-source data fusion and machine learning. The method includes: acquiring hydrological monitoring data, including flow rate, tidal level, wind vector, and reservoir salinity; constructing an input feature set by performing physical feature derivation processing on the data: calculating tidal range features based on tidal level to characterize tidal dynamics, calculating regional average features based on wind vector to characterize wind field driving, and performing phase correction on the flow rate data according to the runoff-salinity lag relationship; combining the above-mentioned derived features with basic tidal level features and historical salinity features, and inputting them into a pre-trained neural network model. This model uses a bidirectional long short-term memory network layer to capture temporal dependencies and utilizes a multi-head attention mechanism layer to dynamically focus on key information, outputting the future salinity prediction value of the target reservoir. This invention can ensure rapid response and high computational efficiency while possessing excellent prediction accuracy and stability, and ensuring that the prediction results conform to hydrophysical laws.

The invention relates to the technical field of corrosion tests and equipment, in particular to a tidal range natural acceleration device and a test method.Seawater liquid level changes are monitored in real time through a liquid level sensor, the natural rising tide frequency a and falling tide frequency b of the previous day are obtained, a sample frame is controlled to execute up-down reciprocating motion at N times of frequency, and N is the acceleration rate; and after a plurality of test periods, respectively measuring the corrosion rates of the accelerated test and the naturally exposed sample, calculating the acceleration ratio, and constructing a gray prediction model based on the relationship between the acceleration ratio and time for extrapolating and predicting the natural corrosion behavior of the material in a longer period. According to the invention, a mechanical lifting system capable of being accurately controlled is constructed in a natural seawater tidal range region, so that the frequency of a material drying and wetting alternation process is enhanced, and the corrosion process is obviously accelerated on the premise of not changing the authenticity of a marine environment; the double problems that a traditional indoor acceleration test is poor in correlation with the actual service environment and the natural exposure test period is too long are solved.

This invention discloses a method for estimating long-duration design tidal process lines, comprising: preprocessing and frequency analysis of historical tidal data to obtain the design high tide level, design flood tide range, and design ebb tide range; selecting a typical long-duration tidal process containing the highest tide level, and selecting a "one flood, one ebb" process at a later position as the main tidal type according to the principle of "high tide level - long duration - later high tide level", with the rest being secondary tidal types; using the design high tide level, design flood tide range, and design ebb tide range to perform same-frequency combination design on the main tidal type to obtain the design main tidal type process; using the scaling ratio of the corresponding phase points of the design main tidal type and the measured main tidal type as a benchmark, scaling the secondary tidal types accordingly to obtain the design secondary tidal type processes; and splicing the results to obtain the complete long-duration design tidal process. This invention overcomes the limitation of existing methods that can only deduce "one flood, one ebb" processes and is applicable to the calculation of any long-duration design tidal process.

The invention relates to a large tidal range strong back-silting sea area steel pipe pile construction method based on harbor basin desilting, which comprises the following steps: S1, arranging a plurality of harbor basins at the upstream of a bridge along the axis direction of the bridge, and enabling the water depth of the tide level where the harbor basins are located to be not lower than a first preset value through desilting; s2, the pile driving barge sails to the position of the harbor basin and is anchored and positioned; s3, when the tide level is lowered to be lower than the first tide level, the pile driving barge conducts construction preparation operation of the steel pipe piles in the harbor basin; s4, when the tide level rises to be larger than the second tide level, the pile driving barge moves to the target pier, steel pipe piles are inserted and driven, and returning is completed and the pile driving barge stops in the harbor basin before the tide level is lowered to be lower than the first tide level; and S5, according to the tide period, the pile driving barge is moved, and the step S3 and the step S4 are repeated till construction of all the steel pipe piles on the upstream of the bridge is completed. A harbor basin point is used as a construction operation preparation area, so that the back-and-forth navigation time between a construction area and an anchoring ground caused by insufficient tide level is effectively shortened, and the pile pitching efficiency is improved.

The invention discloses a sacrificial anode device of a steel structure and a preparation method thereof, the sacrificial anode device comprises a fixing device, a plurality of sacrificial anodes and a filler, the fixing device is arranged on the outer side of the steel structure, the plurality of sacrificial anodes are arranged between the fixing device and the steel structure, and the filler is suitable for filling the peripheral sides of the plurality of sacrificial anodes. The sacrificial anodes are connected to the steel structure through wires, and the sacrificial anodes are formed by wrapping active metal in long-acting activation mortar. According to the method, the problem that traditional coating protection, underwater sacrificial anode protection and impressed current cathode protection cannot fully protect the steel structure in a tidal range zone and a splash zone can be effectively solved.

The invention discloses a modularized tidal range self-adaption efficient transduction wave energy power generation device, and belongs to the technical field of ocean renewable energy source development and utilization. The device comprises a tidal range self-adaptive mechanism which is fixedly arranged on the breakwater and used for adjusting the position of a floater; the swing arm bracket is arranged at the bottom of the tidal range self-adaptive mechanism and is used for connecting the floater with the tidal range self-adaptive mechanism; the floater is arranged at the front end of the swing arm bracket and is fixedly connected with the swing arm bracket; the easy-to-replace hydraulic cylinder assembly is arranged on the swing arm bracket, and the upper end of the easy-to-replace hydraulic cylinder assembly is adjustably connected with the tidal range self-adaptive mechanism through an angle adjusting assembly; the hydraulic linkage mechanism comprises a linkage hydraulic station and a hydraulic pipeline and is used for achieving energy complementation of the multiple power generation units. Tidal range self-adaption, angle adjustment, hydraulic joint compensation and an easily-replaced hydraulic cylinder are integrated, a modular framework is adopted, parameters can be adjusted according to tidal ranges and wave intensity of different sea areas, the energy capturing efficiency is improved, and commercialized application of wave energy is promoted.

The invention discloses a concrete microbial corrosion simulation device and a microbial corrosion simulation method in a marine environment, and relates to a concrete microbial corrosion simulation device and a simulation method. The problems that existing concrete microbial corrosion can only simulate a single corrosion zone and only a single acid-producing microorganism is selected for simulation, so that the simulation result is inaccurate are solved. The device disclosed by the invention realizes laboratory in-situ simulation of three typical microbial corrosion areas, namely an atmospheric area, a tidal range area and a total immersion area of a marine environment, and has the advantages of good simulation effect and high automation degree. According to the experimental method for corroding the concrete through the synergistic corrosion microorganisms, a solution is provided for the experimental method for subsequently exploring the effect and mechanism of corroding the concrete through the synergistic acid-producing microorganisms in different corrosion zones in the marine environment, the actual situation is better met, and subsequent research on the mechanism of corroding the concrete through the microorganisms is facilitated.

The application discloses a design water level calculation method and device for an unobserved sea area. The method comprises the following steps: acquiring measured data of a marine station adjacent to a target unobserved sea area, wherein the measured data of the marine station comprises a measured mean tidal range and a measured design water level; constructing a correction formula according to the measured data of the marine station, wherein the correction formula comprises a corresponding relationship between the mean tidal range and the design water level; training a numerical model with a tide level simulation function by using the measured data of the marine station to obtain a calibration model; calculating a simulated mean tidal range by using the calibration model; and obtaining a design water level of the target sea area according to the simulated mean tidal range and the correction formula. The design water level calculation method and device for the unobserved sea area can accurately calculate the design water level of the unobserved sea area, and have high flexibility and applicability, and can adapt to different sea area engineering layout requirements.

This invention relates to the field of testing equipment technology, specifically to a stainless steel corrosion performance testing equipment for a full-zone simulated seawater environment. The equipment includes: a test chamber, which is vertically arranged along the interior of the chamber via multiple partitions, sequentially from top to bottom, comprising an atmospheric test zone, a splash test zone, a tidal range test zone, a full immersion test zone, and a sea mud test zone; and a simulation unit, including a sea breeze simulation component and a wave simulation component respectively connected and installed on the side wall of the test chamber, for providing a simulated seawater environment. By separately setting the atmospheric test zone, splash test zone, tidal range test zone, full immersion test zone, and sea mud test zone inside the test chamber, the equipment can work with the sea breeze simulation component and the wave simulation component to simulate a full-zone seawater environment. This allows for convenient testing of the corrosion resistance of stainless steel pipes in different zones of a simulated real marine environment, improving the accuracy of the test, reducing the manpower and material resources consumed in the test, and reducing the workload of the personnel involved in the test.

The invention belongs to the field of marine antifouling, and particularly relates to a composite material (CeO2-MOF / C) with halogenated peroxide mimic enzyme catalytic activity and preparation and application thereof. The specific method comprises the following steps: adding activated carbon black into a CeO2-MOF precursor, and calcining an obtained sample in a muffle furnace at 350 DEG C for 2 hours to prepare a CeO2-MOF / C composite material; wherein the precursor of the CeO2-MOF is 4, 4-diphenyldicarboxylic acid and ceric ammonium nitrate; the mass ratio of the precursor 4, 4-diphenyldicarboxylic acid to the ceric ammonium nitrate is 1: (1-1.5). The antifouling coating is constructed on the basis of cerium-based halogenated peroxide bionic enzyme, the prepared antifouling coating is used for antifouling application in real sea environments, and the real sea environments comprise a sea total immersion zone and a tidal range zone. The antifouling coating has no pollution to the marine environment, is green and environment-friendly, and has a wide application prospect in marine fouling protection.

The invention relates to an anti-corrosion construction method for an offshore wind power foundation, belongs to the technical field of ocean engineering anti-corrosion, and solves the technical problem that the anti-corrosion service life of a foundation structure cannot meet the design requirement of a wind power plant due to the fact that a traditional single coating system is prone to early failure, pitting corrosion and stripping in a severe ocean environment, especially in a splash zone and a tidal range zone. The method comprises the following steps: carrying out sand blasting treatment on the outer surface of the steel structure until the cleanliness is Sa2.5 level and the roughness Ry is 60-100 microns; spraying a zinc-aluminum alloy bottom layer containing repairing microcapsules in the splash zone and the total immersion zone in an electric arc manner; coating an epoxy micaceous iron interlayer added with 0.5-1.5% of functionalized graphene oxide, wherein the thickness of the epoxy micaceous iron interlayer is 300-450 [mu] m; and finally, coating a fluorocarbon resin or polysiloxane surface layer, and scanning and curing by adopting intense pulsed light at the energy density of 5-15J / cm and the pulse width of 1-5ms. The method is mainly used for improving the long-term protection performance and prolonging the service life of the offshore wind power foundation structure in the corrosion environment.

The invention discloses an offshore photovoltaic system adapting to tidal range and an installation method thereof, and belongs to the technical field of offshore photovoltaic power generation. The system comprises a plurality of fixed pile foundations, the bottoms of the fixed pile foundations are fixedly arranged on the seabed, the tops of the fixed pile foundations are exposed out of the sea surface, sliding rings are arranged on the fixed pile foundations in a sliding mode, the sliding rings are connected with a photovoltaic module supporting platform through flexible fixing devices, and photovoltaic modules are arranged on the photovoltaic module supporting platform; the buoyancy of the photovoltaic module supporting platform and the slip ring is greater than the dead weight; and a plurality of buoy structures are arranged below the photovoltaic module supporting platform. According to the invention, a closed loop of'dynamic adaptation and load buffering 'is formed through structural innovation, the dependence of traditional fixed offshore photovoltaic on sea areas with small tidal range and weak waves is broken through, a reliable solution is provided for a complex marine environment with high tidal range and strong waves, large-scale popularization of offshore photovoltaic to wider sea areas is promoted, and economic and environmental benefits are both achieved.

The invention discloses an overall rapid construction method for a pouring jacket cofferdam under the condition of a strong tidal range sea area, which comprises the following steps: building a construction platform, and inserting and hitting a steel casing and a positioning column on a riverbed; a single-wall steel cofferdam is built on the construction platform, and limiting profile steel corresponding to the positioning columns is arranged on the periphery of the single-wall steel cofferdam; the single-wall steel cofferdam is lowered, and meanwhile, the limiting profile steel penetrates through the positioning columns till the single-wall steel cofferdam falls to a riverbed; pushing mechanisms are arranged on the positioning columns, and the single-wall steel cofferdam is pushed downwards through the pushing mechanisms until the single-wall steel cofferdam reaches the preset depth; desilting, bottom sealing concrete pouring and water pumping are conducted on the interior of the single-wall steel cofferdam; pier construction is conducted; hoisting mechanisms are installed on the positioning columns to lift the single-wall steel cofferdam until the single-wall steel cofferdam is separated from the riverbed; and the single-wall steel cofferdam is integrally hoisted and then dismantled. Compared with the prior art, the stability of the single-wall steel cofferdam under the high-tidal-range and high-storm sea condition environment condition is improved through the positioning columns.

The utility model relates to the related technical field of ship charging, in particular to an electric tug charging device which comprises a supporting frame and a force arm rotationally installed on the supporting frame, and a conveying arm is fixedly installed on the force arm. One end of the cable is connected with a control box, the other end of the cable sequentially bypasses a first guide part installed on the force arm and a second guide part installed at one end of the conveying arm and is provided with a connecting plug, and the winding directions of the cable on the first guide part and the second guide part are opposite. Rotation and stretching of the conveying arm can be remotely operated and controlled through the control box so as to be suitable for charging work of electric tugs of different sizes, the influence of large tidal range between ships and shores is avoided, the number of needed personnel is small, personnel on the ships and the shores are easy to cooperate, and safety is high; and meanwhile, under the cooperation of a guide plate and a limiting wheel, the movement of the cable is guided and limited, and the cable can automatically contract when charging is stopped.