Abstract:Pinglu Canal project construction scale is huge,involving many specialties,integration and coordination are difficult.On the basis of the canal waterway route demonstration,plane layout optimization and other key content,applications of building information modeling(BIM),geographic information system(GIS),oblique photography and other digital technology means in the project planning stage are explored.In addition,some technical difficulties such as multi-scale and multi-precision data matching and coordinate system transformation of spatial data are studied,and multi-source data fusion and information model construction are realized.At the same time,the application of the digital technology is dug deep into the planning scheme selection,information integration browsing,simulation,virtual roaming etc,and project pre-stage decision optimization and quality effect are assigned.

Abstract:The canal route and cascade scheme are major technical schemes for a canal project,and it is necessary to make multi-factor comparison and selection,dimensional demonstration,and multi-objective decision-making research.In view of Pinglu Canal channel route and cascade layout quantity problems,during the preliminary research and demonstration process of the project,extreme optimization research is conducted on the cascade scheme from aspects of guarantee of water resource and comprehensive utilization,comprehensive development adaptability,flood control safety and along-the-way leakage,traffic efficiency and capacity,land occupation and ecological environmental protection,engineering technical difficulty,engineering investment,etc.After research and demonstration,the extreme optimized cascade scheme and route is not recommended,and the recommended scheme is a three-tier ladder scheme.

Abstract:The horizontal twin-plate breakwater is an advanced permeable structure.Since the wave energy is mainly concentrated on the surface of water body,the breakwater structure can be designed accordingly to realize the function of wave reduction.Based on FLUENT platform,the numerical simulation method is used to compare the action results of five kinds of wave with different incident period,and the wave reduction characteristics and wave pressure distribution of horizontal twin-plate structure are studied.The results demonstrate the structure's effective wave reduction within the tested range,revealing the relationship between the structure's wave reduction efficiency and the relative plate width.Additionally,the wave pressure distribution on the structure's surface at representative time points is analyzed,establishing a connection with the relative plate width.The study of the flow field morphology around the structure provides insights into the wave reduction mechanisms at play.

Abstract:To address the issues of accelerating the formation and improvement of the overall layout of the national high-grade waterway and building a golden waterway for the whole basin,this paper analyzes the development logic of the Yangtze River shipping communication project,summarizes the experience of canal development and construction at home and abroad,and comprehensively analyzes the development ideas of the Yangtze River shipping communication project.The research indicates that promoting the Yangtze River shipping communication project should adhere to the principles of watershed perspective,overall planning,based on the current and long-term,geographical proximity,safety and reliability,moderate advancement,and economic applicability.Ten navigation communication projects are proposed to create an overall waterway pattern of “three horizontal，five vertical and two rings”in the Yangtze River system,which is conducive to maximizing the value of shipping and sharing water resources across time and space.Relevant work suggestions are proposed from the aspects of orderly promotion of classification,factor resource guarantee,major technology reserve,pilot demonstration and so on.

Abstract:Aiming at the impact of waves passing over submerged breakwater on the wave height behind the breakwater,the physical model experiment method is employed to investigate the effects of relative submergence depth,relative crest width,slope gradients of the front and back slopes,and wave steepness on the transmission coefficient of the submerged breakwater under irregular wave action.Based on the experimental data,a formula for calculating the transmission coefficient of submerged breakwater under irregular wave conditions is fitted.The results show that the transmission coefficient decreases with increasing relative submergence depth,relative crest width,or wave steepness.When the slope gradients are within the range of 1:1.0 to 1:2.5,the front and back slope gradients have almost no effect on the transmission coefficient of the submerged breakwater.A comparison between the fitted formula and commonly used empirical formulas shows that the fitted formula can calculate the transmission coefficient of submerged breakwater well.

Abstract:Aiming at the lack of temporary wharf in the assembly and transportation of hydraulic lifting drilling platforms in the port exploration stage in remote overseas areas,this paper takes a port project in West Africa as an example.Through on-site survey and market survey,a gravity-type temporary wharf design scheme with old containers as the main structure is proposed according to local conditions.The article expounds its design ideas and structural characteristics,and uses the finite element model to calculate and analyze the strength of the container structure,ensuring its safety and reliability.Through engineering practice,the construction of temporary wharf is convenient,simple and practical.It successfully solves the problem of drilling platform transportation,and achieves the expected purpose,which has certain reference value.

Abstract:The riverbanks of mountainous rivers are steep,the river cross-section is narrow,and the water level fluctuates greatly.In view of problems such as long shoreline,large amount of earthwork and high project investment,we propose a wharf planar layout type combined steps with S-shaped ramp,which can meet the daily travel needs of mountainous residents and the transportation of production and living materials,and overcome the shortcomings of conventional car-driven ramp wharf.The comparison of engineering examples shows that the wharf layout with steps combined with S-shaped ramp is more adaptable to the terrain characteristics of mountainous rivers.The wharf layout can effectively reduce the occupation of shoreline and the amount of excavation and backfill of earth,reduce the difficulty of construction,and save project investment.

Abstract:The high-piled wharf can accommodate the feature of large water level differences in inland rivers by establishing multiple levels of mooring platforms,which usually adopts steel structures.To the problems of susceptibility to corrosion and high construction and maintenance costs of steel structures,this paper takes the mooring platform structure of the high-piled wharf as the research object and conducts a comparative study of steel structures and optimized concrete structures.By using finite element analysis software for three-dimensional modeling,the stress conditions of the beams and pile foundations are analyzed,and the investments of the two structures are compared.The results show that the optimized concrete structures can increase the integrity of the mooring structure at the front edge of the wharf platform,effectively reduce the maximum bending moment of the pile foundations,and the structure is more favorable.However,the bending moment and shear force of the beams have increased to a certain extent.The optimized concrete structure can significantly lower the project cost and reduce the subsequent maintenance efforts.

Abstract:In China,the existing liquefied natural gas（LNG）terminals in coastal areas mainly meet the loading and unloading requirements for imported LNG carriers,and rarely have the function of reverse loading and unloading of bunkering ships.In order to make intensive use of shoreline resources and reduce project investment,we transform the existing large LNG terminal to meet the berthing and bunkering operation of small bunkering ships,as a scientific and reasonable solution.Taking the transformation of a LNG terminal in Zhejiang Province to increase the bunkering function as an example,we study the center distance of the berthing pier,the applicability of the operation range of the loading and unloading arm joint,and the arrangement of the mooring line,compare the relevant process parameters of the hull with the calculated values of the code,and analyze and verify the adaptability of the unloading arm operation envelope to the hull and wharf structures under different working conditions.Then we use the OPTIMOOR mooring software to simulate the degree of freedom and mooring force of different tonnage ships under different working conditions and environmental conditions.Finally,we propose a solution which adds a berthing facility with a spacing of 32 m,adds a variable diameter pipe assembly,a shore guide cable,a number of cables and other facilities,and appropriately raises the wind and wave height berthing standard according to different wind directions.

Abstract:Based on the classification and statistical analysis of the water traffic accidents in the upper reaches of the Yangtze River trunk line over the years,and in response to the frequent occurrence of water traffic accidents in the Three Gorges Reservoir area and the reach near the dam,multiple factors such as traffic conditions,shoreline conditions,planning conditions and land use conditions are analyzed.Fuguang Wharf in Zigui County is selected to build the first emergency salvage base in the Three Gorges Reservoir area.The water terminal adopts the vertical type to meet the needs of the large water level difference in the reservoir area and the berthing of ships at different water levels.The land area is equipped with training sites and supporting buildings for easy standby of rescue personnel.Modular salvage equipment is used to provide equipment and technical support for fast and professional rescue and salvage.After the completion of the project,the shipping safety of the Three Gorges Reservoir area can be guaranteed,and the emergency handling capacity and the rapid response capacity of emergency salvage can be improved.

Abstract:In view of problems of making full use of the irregular terrain of the project to meet the multifunctional demands and optimize the project investment etc.,a study on coal yard design for bulk cargo wharf in Huanghua Port is carried out.Through the analysis for whole project function needs,the full use of irregular terrain is realized by adopting the same-side access to the yard;the two-way operation of the belt conveyor connected with the bucket wheel stacker and reclaimer is realized by adopting the cross double-tailed vehicle;the demand for different conveying capacity of the belt conveyor is realized by adopting the intelligent control of frequency conversion drive technology;the function of coal screening is realized by adopting the stockpiling machine with the roller screen.All needs are effectively met.The project achieves the expected results.

Abstract:Spur dikes are widely used as regulating structures in inland waterway regulation projects,but their damage phenomenon is very common.Natural water flow is basically unsteady,and different unsteady conditions have different impacts on local scour around spur dikes.The RNGk-ε turbulence model and VOF (volume of fluid) model in FLOW-3D are used to study the effect of unsteady water flow on local scour around spur dikes.The results show that increasing flow variability increases the length and width of the scour hole and the maximum scour depth at the head of the dam,and will also causes the scour width to reach the critical width more quickly.The number of flood peaks affects the formation process of the maximum depth of the scour hole,and the later the flood peak appears,the smaller the development rate of the maximum scour depth.The length and area of the scour hole are not significantly related to the number of flood peaks,but the greater the number of flood peaks,the faster the scour hole width will reach the critical value.The longer the duration of the flood,the slower the rate of increase of the maximum depth of the scour hole,which eventually reaches the critical value.The longer the flood duration,the larger the length and area of the washout pit,and the later the width of the washout pit reaches the critical value.The research results can provide technical support for maintaining the stability of spur dikes during flooding.

Abstract:Aiming at the problems such as uneven distribution of the approach channel along the lateral and heavy load on ships in the berthing section when the downstream approach channel of ship lock is arranged asymmetrically,the water level fluctuation characteristics,surface flow field structure and ship stress characteristics in the downstream approach channel during the unsteady flow of ship lock are studied.Based on a typical ship lock project,the whole hydraulic physical model of ship lock with a scale of 1:30 is studied.The test results show that,in view of the overall layout of the asymmetric approach channel,the combined arrangement of the sill in the discharge channel should also be asymmetric,so as to adjust the transverse shunt ratio in the approach channel,and the sill should not be too close to the drainage outlet,so as to avoid the flow blocking effect.Under the premise of not producing backflow,appropriate reduction of the side flow of the berthing section can significantly improve the conditions of the ship's berthing stability.The research results can provide reference for the design and research of energy dissipator of ship lock approach channel and outlet.

Abstract:During the construction period of west sluice of Suzhou River in the Wusong River project,a open diversion channel navigation method is adopted.There are many unfavorable factors such as bridge with piers in water,pump gates,high voltage iron tower,and bends in the upstream and downstream of the channel,making the navigation conditions complex.To ensure the safety of ship navigation and analyze the adaptability of water flow conditions in open diversion channel to ship navigation,a two-dimensional hydrodynamic numerical model is established using numerical simulation calculation methods.The flow state of water flow under various working conditions during construction is analyzed and calculated,with a focus on verifying the navigation water flow conditions in open diversion channel,upstream and downstream bridge areas,bends and other high-risk navigation sections.The results show that the flow conditions of the open diversion channel meet the regulatory requirements and are feasible for navigation.The relevant analysis provides a basis for the layout of open channel routes,determination of navigation technical parameters,and setting of navigation support facilities.The research results can provide reference for similar projects.

Abstract:Since the Three Gorges Reservoir was impounded to 175 meters,the conditions of the navigation channel in the upper reservoir section of the Yangtze River have been greatly improved.However,the navigation channel in the tail section of the reservoir still has many reef obstruction problems during the flood season.Remedial measures need to be taken to improve navigation conditions.Taking Heshangtan,a staggered rapids in the upper reaches of the Yangtze River from Fuling to Fengdu,as an example,aiming at the problem of navigation obstruction during the flood season,the causes and characteristics of navigation obstruction are analyzed by collecting actual measurement data and combining it with a two-dimensional water flow mathematical model.On this basis,corresponding rectification plans are proposed and the rectification effects are analyzed.The results show that by taking remedial measures to remove the reefs at Heshangtan on the right bank and Guojiazui on the left bank,adverse flow pattern problems such as rapid flow speed in the flood season at Heshangtan strong cross currents at the front of the reefs,and strong backflow behind the reefs can be effectively improved.The research results can provide technical support for the improvement of the staggered-mouth rapids in the tail section of the Three Gorges Reservoir.

Abstract:The Three Gorges Reservoir's water storage operation has led to a riverbed reshaping process in the Jingjiang River section of the middle reaches of the Yangtze River,resulting in significant scouring and silting adjustments of the riverbed.The Majiazhai Waterway,as one of key waterways,requires a comprehensive analysis of its riverbed evolution to understand changes in navigation conditions.We utilize the prototype observation data from the Majiazhai Waterway over the years to conduct a comprehensive analysis.The results indicate that the waterway has a single channel with a relatively narrow main channel,offering favorable navigation conditions.The scouring caused by the clear water discharge from the Three Gorges Reservoir is continuously developing.For the foreseeable future,this river section will continue to exhibit characteristics of scouring as the main change.Under normal hydrological years,the scouring will be slow,and during years with major floods,the right bank beach may experience scouring and downstream movement,with the tail end being dispersed.However,due to the limited river width and the limited scale of the beach,the impact of scouring on the river channel and navigation is generally controllable.

Abstract:To the problem of excessive water level variation in the upstream approach channel during the irrigation time of the Three Gorges ship lock when the upstream water level of the Three Gorges ship lift is below 150 m,this paper studies the relationship between the water level of the upper lock of the Three Gorges ship lift and the irrigation time of the Three Gorges ship lock.Theoretical analysis and numerical calculation methods are used to study the variation law of the water level at the upper lock of the Three Gorges ship lift after the wave superposition in the irrigation approach channel of the north and south lines of the Three Gorges ship lock.The mathematical relationship between the maximum water level change at the upper lock head of the Three Gorges ship lift and the double-line irrigation time of the Three Gorges ship lock is obtained,and the early warning method for the upstream water level of the ship lift is proposed.By comparing the actual data with the theoretical prediction and calculating the error value,the accuracy results of the prediction model are obtained.The results show that the early warning method of upstream water level of the ship lift established by the prediction model can provide reference for the safe operation of the ship lift.

Abstract:To constraints of the existing double line ship locks on the third-line ship lock of Changsha hub,and complex boundary conditions (roads,existing ship locks,control buildings,etc.),this study conducts comprehensive comparisons including dam site selection,ship lock axis arrangement,and layout optimization.The navigation conditions at entrance areas and connecting segments are validated through experiments.By comparing straight entrance-curved exit layout with curved entrance-straight exit layout,the straight entrance-curved exit scheme is identified as optimal.It is proposed that the layout selection should integrate multiple factors:land utilization,surrounding constraints,hydraulic conditions,implementation feasibility,lock transit efficiency,interference with existing ship locks,and investment costs.The existing resources should be fully utilized in combination with the engineering practice to reduce the engineering investment and give consideration to the convenience of engineering construction and operation management.The general layout scheme and related technical measures of the ship lock have reference significance for the layout of multi-line ship locks with complex surrounding environment.

Abstract:Based on the foundation construction of an approach bridge for a coastal wharf project in Zhoushan Port area of Ningbo,this study focuses on the construction challenges of pile foundations for the approach bridge in areas with weak overburden layers,an in-depth study is conducted on the pile stabilization technology of artificial crushed stone bedding layers.By constructing an artificial crushed stone bedding layer,the bearing capacity of the weak foundation can be improved,the stability of the pile foundations can be enhanced，and the safety and reliability of the approach bridge structure can be ensured.The bearing capacity of artificial crushed stone bedding layers with varying thicknesses under different loading conditions is analyzed by combining field tests and numerical simulations,and the feasibility of this process is verified through engineering examples.The results show that the artificial crushed stone bedding layer can effectively improve the bearing capacity of weak foundations,significantly enhance the stability of pile foundations,meet engineering design requirements,and provide valuable references for similar projects.

Abstract:This study focuses on the vibro-replacement stone columns composite foundation treatment scheme adopted for the Jiangxi Xinjiang Shuanggang navigation lock due to limited excavation scope.Numerical simulations are conducted using the finite element method based on the elastoplastic constitutive model,and a comparative analysis is performed with actual observation data.The research investigates the application of vibro-replacement stone columns composite foundation in navigation lock engineering,with emphasis on analyzing the settlement control effect of the stone columns composite foundation.Through the finite element model calculations,the settlement of the composite foundation is obtained and compared with field observation data.The research conclusions indicate that the settlement calculated using the finite element method has a linear negative correlation with the elastic modulus of the composite foundation soil.Increasing the elastic modulus of the composite foundation soil can effectively reduce the settlement.The measured settlement is in good agreement with the model calculated using the field plate load modulus.

Abstract:For the design of the section and structure of the sloping breakwater,the calculation formulas and methods recommended by the current industry code mainly come from the actual project investigation and statistical data,the related model test data,and the foreign related research results,etc.,which are universal and instructive.However,there are no detailed provisions on the relevant contents such as sea-floor gradient and sudden change of water depth in front of the sloping breakwater,and the offshore wave elements are greatly affected by terrain and water depth,especially in the complex seabed terrain such as reef-plate,because of the complexity of wave motion,the conventional design method is not applicable.In this paper,the design cross sections of sloping levees in different seabed topography are verified by physical model tests,the differences between the design code and the model test results are compared and analyzed from the aspects of the structure of the protective face,the prisms of the protective feet,the overtopping volume and the stability of the breast wall,and relevant suggestions are given,which can provide references for similar projects.

Abstract:The long-distance flotation of large-scale immersed tubes has consistently posed a substantial challenge in the construction of immersed tube tunnel projects.The Shenzhen-Zhongshan Link's immersed tube,for instance,necessitates a flotation distance of 50 km,which involves multiple channel transitions and faces huge construction risks.Physical model tests are carried out to examine the floating posture of the immersed tube under high-speed conditions.The in-situ measurement of immersed tubes' trim attitude is carried out in the construction of Shenzhen-Zhongshan Link.The results show that the maximum pitch angle of immersed tube can reach 0.27° at a floating speed of 5.12 kn in physical model tests.When following waves,the maximum pitch angle at the same floating speed decreases to 0.16°,and a notable water uplift phenomenon occurs at the top of the immersed tube during this phase.The actual measurement data align generally with the trends observed in the physical model tests.At an actual ship speed of 4.25 kn on-site,the measured maximum pitch angle of the immersed tube is 0.19°,affirming the conclusions derived from physical model tests.

Abstract:n the installation of superstructure of high-piled wharf,the traditional floating lifting process has problems such as poor adaptability to harsh sea conditions and low level of equipment intelligence.Relying on the berth 3 project of Dafeng Port Phase III General Wharf in Yancheng Port,Jiangsu Province,the rapid installation technology for superstructure of high-piled wharf based on intelligent installation platform has been developed.The application results show that the installation platform has high wave resistance in open sea areas,and has the functions of quickly installing prefabricated longitudinal and transverse beams,berthing components,prefabricated panels,and assisting cast-in-place pile caps.The automation level of component installation is improved,with a plane accuracy of ±1 cm,the installation efficiency is improved by 42% on average,the number of operators is reduced by 58%,and the full-coverage and streaming installation of prefabricated components is realised.This technology promotes the superstructure installation of high-piled wharf to industrialisation,intelligence,green and low-carbon progress,and the application effect is remarkable.

Abstract:In response to the problem of large errors in traditional cutter positioning methods,a high-precision cutter positioning method is studied taking the channel slope construction of a dredging project abroad as an example.The high requirements for slopes in foreign dredging projects have made it difficult for the traditional cutter positioning method to continue,resulting in a significant decrease in construction efficiency and an increase in labor and material costs.By using the methods of the error analysis of the cutter plane system and the verification of ship plane positioning,error analysis and verification of cutter excavation depth system,and cutter envelope digging correction,through theoretical calculations and effectiveness verification,a high-precision cutter positioning method for a cutter suction dredger based on channel slope excavation is summarized,which greatly improves the accuracy and quality of slope construction.The results can accelerate the implementation and popularization of automatic dredging systems,providing reference for high-precision construction of similar cutter suction dredgers.

Abstract:In view of problems of low breaking efficiency and serious wear of hammer head when using drilling + rock drilling (DRD) rock breaking process to deal with extremely solid rock on the seabed of a certain anchorage,simulation and engineering tests on the effect of rock breaking on extremely solid rock under different drilling spacing are carried out.The development process of internal stress damage and the breaking effect under different pore placement parameters are analyzed.The results show that when DRD removes extremely solid rock from the seabed,the best rock breaking effect is achieved by using a 35 t axe type rock drill hammer to break the rock mass at a 0.4 m×0.5 m（width×length）drilling spacing.Influenced by the shape of the hammer head and the airspace,the internal stress of the rock mass spreads to the two sides of the parallel hammer head,the side of the airspace,and the deep part,forming a damage area dominated by tensile and tension-shear damages.Compared with the square hole placement scheme,the rectangular hole placement scheme significantly enlarges the damage range and has better rock-breaking effect.

Abstract:In view of the accuracy and reliability of control points of provincial continuously operating reference stations(CORS) network in long-distance canal control network,a comparative analysis is carried out.On the basis of the Pinglu Canal project and control points established by the provincial CORS network,we use the traditional global navigation satellite system(GNSS) static networking method to test the plane coordinate accuracy of control points calculated by the provincial CORS network,and use the third-class leveling results to test the precision of the quasi-geoid elevation results calculated by the CORS network.The results show that the precision of plane coordinates calculated by the CORS network is accurate and reliable,and the precision of quasi-geoid elevation can reach the root level.This method not only has high operating efficiency,but also has good economic benefits,and has guiding significance for follow-up control network measurement methods in similar long-distance canal construction.

Abstract:The excavation of hard clay has long been a challenging issue in the dredging industry.To address the problem of low dredging efficiency of hard clay in Lianyungang area,this paper employs discrete element-based fluid-solid coupling numerical simulation to study the cutting characteristics of clay grab heads,examining the dredging process for clays with different cohesion levels.The results show that the conventional high-pressure water jets are effective for dredging soft clay,but when dredging hard clay,high-pressure water cannot penetrate the soil,leading to a series of issues such as high cutting resistance and drag head blockage.Therefore,when excavating hard clay,it is necessary to increase the high-pressure water jet pressure to increase dredging efficiency.

Abstract:Due to the invisibility of underwater operations,the dredging construction of cutter suction dredgers not only affects the construction quality of the project,but also affects the accurate determination of production performance to a certain extent.Accurately grasping the production efficiency of cutter suction dredger rock excavation is an urgent problem that needs to be solved in current engineering construction.Taking the rock excavation test project of a cutter suction ship in the offshore section of the Western Land Sea New Channel (Pinglu) Canal estuary as an example,based on three-dimensional graphics software,a dredging model of the channel is constructed.The construction quality and excavation efficiency of rock excavation by cutter suction dredger are analyzed based on the statistical data of ship monitoring system.The results show that the analysis method combining three-dimensional models with monitoring system statistical data is more accurate in soil category discrimination and statistics,more precise in mining production efficiency calculation,and more intuitive in construction quality analysis.The research results can provide references for ship construction in the later stage of engineering.

Abstract:A dredging project in Iraq uses large cutter suction dredger to construct foundation trench slope,and the construction period is only three months.To solve the problem that the slope accuracy is high and the cohesive soil is not easy to collapse into slope,we decide to study the high-precision one-time forming technology of large cutter suction dredger for foundation trench cohesive soil slope.By correcting the transverse speed of the cutter and the lifting speed of the cutter,the matching control of the transverse speed of the cutter and the speed of the bridge frame is realized.By carrying out typical construction and a large number of field experiments,the optimal cutter traverse speed of four construction methods under different excavation depths is determined,which includes uphill normal cutter excavation,uphill reverse cutter excavation,downhill reverse cutter excavation and downhill normal cutter excavation,and the quality of the slope is guaranteed.The results show that this technology can meet the requirements of high precision and short construction period,and reduce the production cost.The average super width is reduced from 2.0 m to about 0.5 m,and the slope repair effect is remarkable.

Abstract:Soil disturbance has long been a significant challenge in the engineering field,particularly when it comes to evaluating the degree of soil disturbance and the quality of samples taken by soil sampling equipment.These situations are more difficult problems in engineering practice.Due to numerous factors that contribute to soil disturbance,traditional disturbance evaluation indices fail to adequately reflect the effects of human-induced disturbance,factors that contribute to soil disturbance are analyzed in this paper,and the unavoidable unloading disturbance is separated from the overall disturbance evaluation.A theoretical formula for unloading disturbance is proposed and validated through multiple sampling tests with different soil samplers.Finally,an improved method for evaluating soil disturbance is presented,and can better evaluate the technical level of soil sampling.