Abstract:A three-dimensional dynamic pressure model NHWAVE was used to simulate the wave transmission experiment of a slope breakwater without overtopping,and validated by the experiment data.The effects of wave non-linearity on the wave transmission characteristics of the rubble mound breakwater were investigated using the Ursell number and wave steepness,and relative length(relative breakwater width B/L)was insteaded of absolute length(B)to indicate the width of the breakwater at the calm water surface.On this basis,a new wave permeability coefficient KL was calculated,and the relationship between the wave transmission coefficient and wave non-linearity was discussed.It is suggested that the non-linearity character of waves has a strong influence on the wave transmission coefficient. Finally,based on the results of numerical modeling,an empirical formula of wave transmission coefficient was developed，which provided the reference for breakwater construction and scientific research.

Abstract:By means of numerical simulation and physical experiment,the energy capture and wave elimination performance of two types of arrangement of savonius type paddles for a new type of energy capture and wave attenuation floating breakwater are studied.By using STAR-CCM+numerical simulation software,the three-dimensional hydrodynamic model of floating breakwater is established and numerical simulation is carried out by calling overlapping grid,second-order time discretization and adding numerical iteration method.The physical experiment system of the breakwater is developed,and the energy absorption and wave elimination performance of the floating breakwater is tested.The results of numerical simulation and physical experiment are analyzed.The results show that the new type of floating breakwater has the largest energy harvesting power when the rotating frequency of the blades is close to the wave frequency,and the wave elimination performance of the parallel arrangement of the blades is better than that of the vertical arrangement of the blades.

Abstract:According to the horizontal plate-type breakwater and inclined plate-type breakwater,we propose a“厂”-type breakwater and study the wave dissipation performance of it by numerical simulation method. At first,we establish the two-dimensional regular wave numerical model based on the software FLUENT,and verify the effectiveness of the water tank. Then,we obtain the variation of wave height behind the breakwater-time relationship through simulation,analyze the transmission coefficient,and discuss the relationship between the transmission coefficient of new breakwater and the wave height,wave period,opening rate of the breakwater,relatively plate width,wave steepness,angle between inclined plate and horizontal plate and the distance from still water level to the structure top. The results show that within the simulation scope,the breakwater has a transmission coefficient and wave absorption performance,especially for the long-period wave.The research result may serve as reference for the design of new-type breakwater.

Abstract:Grasping the law of sediment movement in Guanhe estuary sea area is the basis for studying of waterway regulation.Taking the sediment collected on site as the research object,we study the suspension law of sediment in Guanhe estuary under different water depths,wave periods and wave heights by large wave flume test,and research the sediment settlement characteristics under different initial concentrations and water depths by static water settlement test.The results show that the sediment concentration in the upper part of the water body is small and vary little along the vertical line under the limiting wave height,but the sediment concentration near the bottom is large.Overall,the sediment concentration near the bottom is 0.25 kg/m3 to 0.96 kg/m3 higher than that in the upper water.The range of sediment settling velocity is 0.08 cm/s to 0.20 cm/s under different water depths and initial sediment concentrations,which is the same order of magnitude as that of single sediment.The flocculation of sediment is weak in Guanhe estuary sea area.

Abstract:The location of the closure gap belongs to the area where the velocity increases suddenly and the flow field is complex,so it is of great significance to accurately predict the scour pattern for the structural design and safe operation of closure gap.Relying on a large-scale overseas reclamation port project,with the aid of CFD software,we carried out the 3D numerical calculation of local scour characteristics of closure gap of different structures under strong overtopping waves during the construction period,and obtained the distribution regularities of flow field and local scour pattern around closure gap respectively,thus provided some suggestions on erosion protection.The results show that the flow field around closure gap is complex,but there is a certain law,and its characteristics have a certain corresponding relationship with the local scour factors of the closure gap.If a sand retaining structure is set in the closure gap area,there is a risk of scouring below it,which is easy to form a scouring channel.When scour develops to a certain extent,it will disturb the original flow field behind the closure gap and aggravate the scour degree at the bottom and back of the closure gap.

Abstract:The annual variation of temperature will cause the uniform change of temperature in the structure,which will cause the deformation and internal force in the structure,and the effect of temperature will often cause adverse influence in high-piled wharf projects.In order to analyze the temperature effect of beamless-slab high-piled wharf,on account of the heat conduction law of infinite slab,we establish the finite mesh model with ABAQUS based on the real engineering projects.Based on the hourly meteorological data in Hangzhou,the variation characteristics of temperature,the temperature difference field of slab,the structural deformation and displacement were studied,and the selection of basic temperature was discussed.The results show that air temperature presents one-dimensional heat transfer characteristics mainly in thickness direction in beamless slab and temperature field is uniformly distributed in horizontal direction.The annual variation of air temperature hardly attenuates in the panel,and the influence of daily variation on the panel temperature can not be neglected.Temperature response of foundation piles of beamless-slab wharf is controlled by the overall temperature difference of the slab,and the two changes are simultaneous.

Abstract:In view of the problem that the structural safety risk is caused by the serious corrosion at the lower chord of steel approach bridge of Qingdao Port phase I oil-wharf,we study the design of temporary strengthen,apply the strengthen method of load shedding with pre-stress to the steel strand of lower chord,ensure the structural safety in the process of comprehensive strengthen,and form the strengthening technology of unload steel truss bridge.The key technology includes the arrangement plan of steel strand,end anchorage,steering block and damping measure etc.The results show that the strengthen technology has the advantages of light-load and high-speed,which can be used for temporary structure and permanent stressed member.This technology can provide the references for the similar projects.

Abstract:In order to improve the berthing stability condition of continuous wharf under the influence of long period wave,combined with an engineering project,this paper analyzes the characteristics of the line tension and the movement of the ships moored by the continuous wharfs under the influence of long-period waves by using the numerical analysis software,and puts forward the key factors to improve the berthing stability under the influence of long-period waves.The results show that the mooring lines tension force and moored ships movements will increase significantly as the period of the wave increases,and the key of mooring optimization is to improve the elasticity of the mooring system so as to absorb the motion energy of the ships.The mooring optimization measures include adding the mooring line’s length,using the non-rigid mooring line or increasing the nylon tail’s length.After the mooring optimization measures being adopted,the mooring lines tension force can be reduced significantly under the influence of long period wave and the purpose of mooring layout optimization can be achieved.

Abstract:Aiming at the problem that there are large quantity of precast concrete and underwater construction inconvenient in traditional gravity wharf,we optimize the wharf structure based on the port engineering in Panama,develop a new type of steel frame gravity wharf structure combining with the concept of Gabion net cage applied in the inland river wharf,and analyze and evaluate its performance.The results show that this structure type is novel and clear mechanical behavior,it can effectively reduce the concrete quantity and the construction process,improve the underwater construction efficiency and shorten the construction period.This structure also has achieved good social and economic benefits,which can provide references for the similar projects.

Abstract:Based on the current situation of port construction along the sea leading to the coastal and land ecosystem degeneration of environment,we take the container port as an example to research the low impact development of docklands,incorporate the sponge city low impact development concept into the construction,and propose the runoff of low impact development control requirements of each functional area in the port area by introducing a reasonable analysis model of hydrological runoff.At the same time,we apply the innovative design of plane and structure to satisfy the control requirement of low impact,and promote the recycling area of rain flood resources.The results show that the main ones suitable for low impact development are general cargo and container yards among all kinds of wharfs,and sponge port area needs to focus on low impact development of yard and road.

Abstract:Crossflow is one of the key technical problems in the construction of Dongying Port and channel.Aiming at the flow conditions of the channel with different arrangements of breakwater and sand barrier in Dongying Port,we carry out the physical model test on the tidal current to analyze and study.The results show that after formation of the south and north breakwaters,the flow velocity at the entrance channel is relatively high,so it is necessary to build a breakwater to retain sand from the point of view of improving navigation conditions.When the submerged dike of the breakwaters keeps the same slope and the lifts are constructed to -12 m and -14 m respectively,the flow velocity at the entrance channel decreases gradually,and the cross flow at the entrance decreases accordingly.With the increase of the breakwater’s top elevation breakwater,the overflow velocity at the head of the breakwater will increase to a certain extent.It is suitable to build the head of the embankment to -14 m and the elevation of the top of the breakwater to -8 m.

Abstract:Considering the interaction between the Yangtze waterway transport and the ecological environment,the carrying capacity concept of resources and environment discipline is introduced,and the connotation of carrying capacity of water transportation of the Yangtze waterway is defined.The algorithm of carrying capacity of water transportation of the Yangtze waterway is constructed,which is related to many factors such as freight volume,waterway capacity,shipping density and ship pollutant discharge.Based on the premise that the total amount of pollutants discharged from ships does not increase,the carrying capacity of the Yangtze waterway in 2035 is obtained.The conclusion shows that if the environmental capacity is allowed to increase moderately,or the transportation organization is further optimized,the technical performance of ships is improved,clean energy is widely applied in ship，and pollutant discharge is controlled,there is still a large space for improving the water transport capacity of the Yangtze waterway.

Abstract:Dredging is one of the most important measures of the waterway improvement,which always produces tons of dredged materials while improving the waterway.For a long time,the dredged materials produced by the waterway improvement projects have not been re-utilized.The simple and rough disposal of the dredged materials is not only a waste of soil resources,but also a pollution to the ecological environment.Based on the analysis of the characteristics of dredged materials and the actual conditions of the waterway improvement project of the Chuanjiang River,this paper explores two ways of utilization of dredged materials for improving the environment and engineering utilization of dredged materials,and puts forward a plan for the utilization of surface sand pebble dredged materials as building materials,bottom sand pebble and block dredged materials for constructing ecological conservation areas,which has received good investment profits and ecological effects,and may serve as reference for the utilization of dredged materials and the construction of inland ecological waterways.

Abstract:Taking the typical curve channels in the Yangtze River Three Gorges Reservoir area as the prototype,we conceptualize it into a model of curve river-type reservoir to simulate the landslide mass in terms of the geometric size of the landslide,the structure of the inner granular structure and the physical indicators.Taking the water depth,angle of slipping surface,thickness and width of the landslide mass,by-water status and the slope of the riverbed at the site where the landslide mass entered the water as the testing parameters,and letting the landslide mass enter the water from the inner bank,we carry out physical model tests to analyze the features of the head wave’s form,determine the head wave height,and explore the distribution of the head wave’s line of crest through the contour map. Following the flow of the wave energy and based on the wave energy theory,we analyze the wave’s kinetic energy,potential energy and work of pressure,and deduce the total wave energy formula theoretically.

Abstract:The reach below Longxikou junction in the trunk stream of Minjiang River is a natural waterway，which has typical mountain river characteristics and is extremely complex in navigation obstruction.In addition,the waterway has been seriously deteriorated due to the influence of sand excavation and stone quarrying over the years.The two-dimensional flow mathematical model of long river is used to analyze and optimize the regulation scheme of 11 rapids in the proposed Longxikou junction of Minjiang River to Minjiang River Bridge section at Pingshan Town.Based on the analysis of the characteristics of navigation obstruction and the causes of rapids,three typical rapids,Ganlongzi rapid,Baijia rapid and Xinkai River rapid,are selected.The comparison and selection of several schemes are carried out from the aspects of the improvement of navigation flow,the stability of trenching and the self navigation of ships on the beach,and the regulation technology of typical representative rapids in the lower section of Minjiang River is summarized.

Abstract:Being one of the key shallow dangerous watercourses in the lower reaches of the Yangtze River,the Dongliu waterway is characterized by multiple channels in the watercourse,dramatic changes of the beach trough,and frequent change of the main and branch channels.After continuous regulations,the conditions of the waterway improved gradually,but it is still difficult to reach the planned standard of 6 m water depth.To provide a technical support for the 6 m deep water project of the Dongliu waterway,we put forward the regulation ideas and schemes by analyzing the characteristics of the river bed evolution and obstruction characteristics of the Dongliu waterway.A physical model was established to analyze the effects of the 6-metre depth engineering scheme.The study shows that after the implementation of the remediation plan,the east waterway can realize the designed scale of 6.0 m×110 m×1 050 m,and a small amount of maintenance dredging is required in unfavorable hydrological years.At the same time,under the engineering effect and with the natural evolution of the river channel,the conditions of the West Harbor waterway will be further improved,which will further enhance the waterway scale.

Abstract:In order to analyze and evaluate the engineering effect of different regulation schemes for the Liutaizi bend reach,a two-dimensional sediment mathematical model was built on SIMHYD-2D platform to simulate the hydrodynamic and bed deformation of the two regulation schemes from Linhuaigang sluice to Lutaizi reach in the main stream of the Huaihe River.The results show that the two-dimensional water and sediment mathematical model can well simulate the hydraulic factors and the distribution of scouring and silting under natural conditions,and can be used to predict the evolution of scouring and silting in the engineering reach.After 10 years of adjustment of scouring and silting,the main channel in Linlu reach is still scouring under the two regulation schemes.The speed of scouring slows down,the beach is still mainly silted,and the whole river channel is scoured.By comparing and analyzing the influence of two kinds of regulation schemes on the movement of water and sediment in the upper and lower reaches,navigation flow conditions and future scouring and silting in the new and old reaches,the second scheme is recommended as the regulation scheme.

Abstract:In view of the influence of seepage and unfavorable geologic condition on the stability of riverbank slope,we analyze the variation law of soil permeability coefficient with confining pressure,saturation density with confining pressure,shear strength of soil with water content and immersion time,construct an unstable numerical model of seepage damage,and probe into the effects of bank cracks,river water softening on the bank slope and rainfall infiltration on safety factor of bank slope.The results show that under the influence of single factor,rainfall infiltration has the greatest influence on bank slope stability,and the safety factor can be reduced by 9.9%,followed by softening effect of river water(2.8%)and bank slope cracks(1.9%).The results of soil-water coupling calculation show that the safety factor of bank slope decreases by 11.3%~21.5% under the combined influence of three factors.

Abstract:The fluctuating backwater area of cascade hydropower station is affected by the discharge of upstream hydropower station and the water level in front of downstream dam,thus the determination of the designed lowest navigable water level is very complicated.Traditionally,the guaranteed rate of designed lowest navigable water level mainly carries on the statistics to the discharge,but the index is not comprehensive enough;moreover,there is certain contingency in the selection of the cases combination for the calculation of designed lowest navigable water level,and the operability is not strong in the actual design process.This paper presents a method for calculating the combined guaranteed rate of inflow volume and water level in front of the dam,which takes into account the probability of the combination of inflow volume and water level in front of the dam.By using this method,the designed lowest navigable water level in the variable backwater area of cascade hydropower stations can be reasonably determined.At the same time,combined with the dispatching scheme of the power station,the channel could be regulated with the least investment in order to achieve the optimal effect.

Abstract:In order to verify whether Daoyunhai waterway regulation project satisfies the navigation requirements of the regulation standards,we select the Doulang-Chuancha Bridge section as the experimental section,apply the 500 tons full load ship designed for this section as the trial ship to carry out the actual seaworthiness test.We measure the depth and topography,surface velocity and direction,navigation mark distribution and water level of the experimental section.We also measure the navigation indexes and navigation status of the test ship in real time,such as the navigation track,the speed of the opposite bank,the rudder angle,the drift angle,the safe distance between the ship and the bank when the test ship navigates up and down the designed route.According to the navigation rules and standards,we analyze and evaluate the rationality of the technical parameters and the distribution of navigation marks after the regulation.The results show that the regulation effect of this test section satisfies the navigation requirements of the regulation standard.The achievement can provide references for the similar projects.

Abstract:Due to limited factors such as existing buildings,land use index,anchorage-free land in outer rivers and bridge-crossing in inland rivers,the layout conditions for the second lock project of western Dazhi River are relatively complex.Considering the factors of flow condition,navigation condition of ship lock,particularity of design ship type,berthing conditions,safety of adjacent buildings and construction conditions comprehensive,this paper determines the reasonable layout scheme of lateral and longitudinal axes of ship lock,obtains the appropriate design dimensions of lock head,lock chamber and approach channel,arranges the internal and external approaching channels asymmetrically,avoids the influence on navigation safety of ship lock when the controlling lock diverts and discharges,satisfies the mooring demand of ships getting in and out of the lock without anchorage in outer river,and achieves the goals of saving land and reducing construction impacts.

Abstract:To analyze the traffic performance of partial constricted section in inland waterway,we design a simulation model according to the channel characteristics of single-line alternating navigation and analyze the traffic performance and capacity of constricted section under different conditions.The results indicate that the size and directional distribution of vessel traffic flow affect the traffic performance:centralized dispatching of vessels when the difference of traffic flow between two directions is large，is beneficial to the improvement of the traffic efficiency，but will increase the delay of some vessels;the traffic capacity decreases with the increase of the length of the constricted section,and approximates a minimum value when the length increases to a certain value.In practice,traffic organization and waterway regulation schemes can be arranged reasonably according to shipping demands.

Abstract:At present,the creation of rebar model of slab-beam wharf on high-piles is difficult and low cost-effective,and cannot satisfy the drawing requirements.It is impossible to realize the delivery requirements based on rebar model in the design stage.We study component-level rebar model technology in design stage,including the creation,drawing,quantity calculation,parametric design and delivery of rebar model etc.Based on the method of combining Revit software and Revit API technology,we propose a parameterized integrated technology of rebar model creation and drawing,and apply it to the actual project.The results show that the technology can quickly create the required rebar model and drawings,which can provide references for the similar projects.

Abstract:In order to solve the problems of the BIM application in deepwater channel,such as the difficulty of unification of multi-source data file format,coexistence of large-scale scenes and small components,and inefficient delivery of results,we carry out a research on the delivery platform of BIM design results in deepwater channel engineering.Adopting the unified modeling standard,lightweight BIM model and development application platform,we solve the problem of difficult delivery of the project results.Research results show that deepwater channel is unique and more professionally complicated than other projects.It is necessary to customize the BIM application platform suitable for its own characteristics and display mode to achieve effective delivery of deepwater channel BIM design results in the infrastructure field.The research results have been applied to Lianyungang Port 300,000 DWT waterway Phase II project and achieved good results.The conclusions of this paper lay a theoretical foundation for the follow-up application of BIM process in the industry.

Abstract:To deal with the floating stability calculation problem of asymmetrical special shaped caisson,firstly,the floating center of arbitrary floating body is theoretically deduced;secondly,according to the structural characteristics of the special shaped caisson,the ballast of the caisson is adjusted so that the projection of the floating center on the immersed surface coincides with the centroid of the immersed surface;thirdly,by using the formula of rotation axis,the principal moment of inertia of the center of gravity of the immersed water surface is found.At this time,the theory of floating stability of symmetrical caissons can be extended to that of asymmetrical special caissons.Through a series of analysis and field operation,it is proved that the theoretical calculation is basically consistent with the actual results,which provides a general method for the floating stability calculation of asymmetric special-shaped caissons.

Abstract:The calculation of compressive bearing capacity of single filling pile is an important part of high-piled wharf and highway bridge design.With the trend of domestic engineering enterprises expanding overseas markets,the engineers are required to master and exercise design codes of different countries in a short time.By comparing Chinese Design Code for Wharf Structures,Design Code for Ground Base and Foundation of Highway Bridges and Culverts,and American AASHTO LRFD Bridge Design Specifications,we obtain the differences and similarities in side resistance and end resistance calculation details and reserve of safety factor.Based on the local drilling geological data of practical engineering,we compare the vertical compressive bearing capacity of single filling pile corresponding to the three codes,and evaluate the advantages and disadvantages of each code.The results show that the two Chinese codes are relatively simple but limited when encountering special soil.The American code has a clear concept and a wider scope of application,but the calculation process is relatively complex.

Abstract:Aiming at the influence of pile foundation on bank slope stability,we analyze the influence of pile spacing,pile edge length and pile length on bank slope stability by means of numerical simulation.The results show that the ratio of pile edge length(pile diameter) to pile spacing determines the effect of pile foundation on bank slope stability based on conditions of the same bank slope and the freedom of pile top.For a specific soil layer,there is a margin ratio(diameter-distance ratio) value,which makes the pile foundation play an optimal role in the stability of bank slope.With the same size and spacing of piles,simply increasing the length of piles in the embedded soil layer cannot improve the effect of pile foundation on bank slope stability.

Abstract:In recent years,during the construction of many bridges,obvious changes have taken place in the channel of the project reach.In order to solve this problem,taking Jingyue Yangtze River Highway bridge pier foundation construction stage as an example,the measured hydrology and topography before and after construction are compared.The results show that the trestle and water construction platform set up during pile foundation construction have caused great changes in Dingjiazhou beach and Nanyangzhou head zone,and has accelerated the development trend of channel conditions in some reaches to the adverse direction,which shows that bridge foundation construction has a great impact on channel evolution.In order to avoid the adverse effect as far as possible,the influence of the possible construction scheme on the channel should be considered in advance in the early stage of span study.If it is difficult to eliminate or reduce the impact by adjusting the construction scheme,the layout scheme of bridge span and pier must be optimized.The analysis results can provide reference for subsequent bridge construction management.

Abstract:In view of the problems occurred in throwing of the tetrahedron-like penetrating frame,such as low efficiency,high cost,poor accuracy and potential safety hazard,we establish theoretical model of the drift distance for the tetrahedron-like penetrating frame during throwing,and obtain the influences of the throwing height,the depth of water,the flow rate,the blocking water area of the tetrahedron-like penetrating frame on the drift distance.We propose an automatic synchronous throwing lifting gear with a large frame and multiple-rotors,increase the number of the permeable tetrahedron frames,anchor the throwing ship precisely by GPS,and monitor the throwing action timely.The results show that the throwing equipment can enhance the throwing precision of the penetrating frame and increase the efficiency of construction.

Abstract:Aiming at the difficulty in predicting the production of the cutter suction dredger,we study the data of the real-time feedback of dredger operations,extract the main process parameters affecting the production of the dredger by the Relief weight algorithm,apply the partial least squares regression to establish a mathematical model between the main process parameters and the production,and achieve the purpose of dredger production prediction.The results show that the mathematical model established by partial least squares regression can predict the production well and provide an effective method for predicting the production of dredger.

Abstract:Domestic dredging projects tend to be large-scale and refined,and the requirement of bedding planeness is higher and higher.For the 50,000-ton waterway project of Laizhou Port,we analyze the hydrodynamic performance of the ship in different wave directions when the ship- borne frame leveling device works based on a small leveling ship named “Hang Gong 301” and establishes a CFD simulation model.We also analyze the economic effects of different construction techniques adopted for the isolated shallow area and shallow concentrated areas,and carry out marine test.The results show that under the action of the leveling device,the motion amplitude response operator of the ship is generally small and the ship has high stability.It is better for the ship to pass through the independent shallow areas in two directions and to pass the shallow areas in multiple directions when the single side is stressed.In the shallow concentration area,the ship passes in S-line and multiple directions,and the spot dredging is carried out from the shallow area to the deep area.Within the construction period,about 103 tons of fuel and 112.5 tons of fresh water are saved,and the shallow sweep rate is 100%.The effect is remarkable.