Abstract:Aiming at the problem of cutting hard clay for submerged high pressure water jet,based on the coupled Eulerian-Lagrangian method,the law of velocity decay of the jet through the submerged water is introduced,and a finite element model is established to analyze the cutting effect,which is finally verified by laboratory test.The method combines the advantages of Euler algorithm and Lagrange algorithm,and is suitable for the analysis and calculation of fluid-solid coupling between jet and soil.The water body adopts the Euler algorithm,and the soil body adopts the Lagrange algorithm.The contact surface of soil and water can be accurately captured.The numerical results show that under the action of high pressure jet,the cutting depth of hard clay decreases with the increase of cutting speed and increases with the increase of jet pressure.Compared with the experimental results quantitatively,the results agree well with each other.The model can well simulate the cutting behavior of high-pressure jet on hard clay under submerged condition,which provides a new research idea for this problem.

Abstract:Coastal vegetation has received widespread attention as a new way of emerging ecological revetment.Aiming at the effect of hydrodynamic factors on the coast evolution,we study the influence of wave and water depth on the quasi-static equilibrium profile of vegetation coast.By means of physical model experiment,we obtain the influence laws of different wave heights and different periodic regular waves on the equilibrium profiles of vegetation coast by qualitative and quantitative analysis,and get the power function relationship between the wave steepness and the dimensionless size of the coast and the variation trend of dimensionless index under different water depth conditions.The results show that the effect of wave height on the equilibrium profile is obvious,and the influence of wave period and water depth is relatively weak.Wave steepness fits well with the dimensionless size of shore-beach,and the fitting result of relative deposition scale is better than erosion size,and the result of wavelet steep region is better than that of large wave steepness region.

Abstract:Aiming at the maximum bearing pressure of the high pressure water tank at the trailing suction hopper dredge is 2.2 MPa，and the high-pressure flushing pressure of the drag head is 38 MPa,it is necessary to design the water intake scheme of the header drag again,so as to provide a mechanism for studying the efficient scour of mud and sand by the high pressure water flushing drag head.Using k-ε in the turbulence model,the mixed grid is used to describe the high pressure flushing state,and three numerical models with different intake modes are established.Results show that the three schemes meet the effect of equable flow at the nozzle outlet,and the average velocity of the three sections is approximately the same.However,the flow field in scheme two of the scheme is quite different,and the velocity of each outlet section of the header is symmetrical along the center of the header.The inflow velocity of the elbow in scheme three varies greatly,which can easily cause damage to the elbow.

Abstract:Based on the physical model experiment,we study the wave run-up and mean overtopping of vertical breakwaters with the wave return wall under irregular wave,and analyze the influence of main factors such as the levee free-board,horizontal extension of wave return wall and wave evenness.The results show that the main factor affecting the wave run-up is wave height,but wave period has little effect on it.Furthermore,the levee free board,horizontal extension of wave return wall and wave evenness are important determinants of the mean overtopping of vertical breakwaters.It is noteworthy that the extent of influence of horizontal extension of wave return wall is related to the levee free-board.On the basis of the physical model experiment,the new calculation formulas on the wave run-up and mean overtopping of vertical breakwaters are set out,which can serve as a reference for the engineering design.

Abstract:The wave run-up is a key factor for determining the crest level of sloping dike and influences the engineering security and cost directly while a big deference existing between the calculating formulas in domestic and international codes and standards.With more and more Chinese enterprises participating in overseas projects,it is necessary for engineering designers to master different calculation methods of domestic and international design standards.This paper introduces the foreign commonly used standard American Coastal Engineering Manual(CEM),the European standard Wave Overtopping of Sea Defences Structures and Related Structures Assessment Manual(EurOtop) and domestic Code of Hydrology for Harbor and Waterway.By comparing the calculation methods of wave climbing and summarizing the differences among the calculation methods,the conclusion that the influence factors of wave climbing calculation taken into account by CEM and EurOtop are relatively comprehensive and practical is obtained.It provides some reference for the selection of wave climbing method in the design of slope seawall.

Abstract:As a kind of non-renewable resource,coastline zone plays a key role in promoting regional economy.Therefore,the study of intensive use of coastline is of great significance for coastline resource management.This paper analyzes the layout pattern of alongside,excavated and jetty wharves,establishes an index model that evaluates the intensive use of coastline for three types to discuss the measures of intensive utilization.The results of the study show that the intensity of coastline use of excavated and jetty wharves are ideally at roughly equal levels,accounting for greater than 1.0,but the alongside wharf reaches the minimum values,accounting for approximate to 1.0.Applicability of various layouts of coastline is affected by factors such as hydrological condition,sedimentation status,topography,storage yard arrangement and handling technology，the coastline planning should be undertaken under restraints of these factors and targeted utilization intensity,and the layout that enables algebraic sum of positive incremental and negative constraining value of shoreline strength to reach maximum value should be given greater emphasis.The coastline-utilization level range of from 2 to 6 is recommended for excavated and jetty wharves.

Abstract:For the complexity of traffic management under the bidirectional free path environment in container terminal,on the basis of considering the AGV physical size,trajectory and driving rules of the vehicle,we set up an environmental map of reasonable grid units,establish a traffic control model of multi-vehicle and multi-task paths,propose an adaptive traffic control method based on path characteristics,and apply the genetic algorithm of rolling scheduling and heuristic strategy to carry out an example test.The results show that compared with the fixed reservation method,the proposed method takes smaller extents as the scheduling interval and forms an adaptive planning period,and the number of reserved raster is more flexible,which realizes the adaptive reservation schedule and blocking avoidance under the flexible section definition,and improves the utilization rate of road resources.

Abstract:Through physical model experiment,we study the influence of the change of embankment top elevation and the wave periodic on the stability of the front,the top and the back sections of the sloping dike under irregular wave and when the slope embankment is randomly arranged with the accropode blocks.The test results show that with the increase of wave period,the stability of the former slope is increasing and the stability of the crown and the back slope is reduced,and the damage position of the slope dike is shifted from the front slope to the dike top and the back slope.Meanwhile,the stability of accropode blocks of the front slope decreases with the increase of the height of the dike roof,and the crown and the back slope reduce firstly and then increase with the increase of the super height of the dike roof.

Abstract:PHC piles with a design life of 60 years were designed for Dares Salaam Port，Tanzania.The differences between Chinese standards and European standards on the structural durability design are compared.Since both Chinese and foreign standards have no structural durability design methods for 60 years of design service life,we use typical concrete structural durability calculation models proposed by researchers at home and abroad,such as the European Duracrete model and the Hongkong-Zhuhai-Macau Bridge model,and take the application environment of PHC piles into account to calculate two control indices for the structure durability,i.e.the thickness of concrete cover and the chloride ion diffusion coefficient of concrete for 60 years’design service life,and propose the control indices of the durability of PHC pile,which obtain the approval.The Chinese standard PHC piles are exported to the international market and a large amount of transformation costs of PHC pile mold are saved.

Abstract:Aiming at the dust pollution problem of coal port,through the analysis research of the present situation of domestic coal port equipment,we put forward a series of technical innovation,such as wet electrostatic precipitator for coal transport system,accurate watering of stacker,equipment modification of the ship loader boom to avoid coal spilling pollution,coal dust collecting device for belt conveyor,return belt cleaning device.The problem of coal dust pollution during loading and unloading process is effectively solved by these technological improvements,and the unorganized coal dust pollution has been transformed into a reasonable and orderly recycling system.The coal dust treatment workshop is designed to avoid secondary pollution,and it has realized scientific and environmental recycling of coal dust.

Abstract:The thin-walled reinforced concrete-filled steel tube composite overhead-vertical structure,as a new type of wharf structure,is applied to practical engineering.However,most of the composite members are in eccentric compression state.At present,there are few researches about the eccentric compressive bearing capacity of thin-walled steel sheath-reinforced concrete composite structures applied to wharf structures,and the final conclusion is still unknown.We make an experiment of the bearing capacity of thin-walled steel tube-reinforced concrete columns under unidirectional eccentric compression,obtain the load-strain curves by failure state and test data of each specimen,and analyze the failure mechanism.The results show that the increase of wall thickness and the decrease of eccentricity have a direct impact on the improvement of bearing capacity of the structure,which can provide reference for the structure design in practical engineering.

Abstract:To explore the influence of the collecting and dispatching ratio of container water-water transshipment on the layout pattern of automated container stacking yard in the automated container terminal project with berths arranging perpendicularly to the shoreline,on the basis of the typical handling process model and layout applied generally in the domestic automated container terminals,we carry out a 3D simulation on two kinds of layout patterns by the software Flexterm,i.e.，the container stacking yard being perpendicular or parallel to the wharf shoreline.By analyzing the horizontal distance of the transport equipment and the influence on the operation efficiency under the two kinds of layout patterns of the container stacking yard,we summarize the adaptability of the two layout patterns for the automated container terminal project which is arranged perpendicularly to the wharf shoreline,to provide a theoretical basis for the design of similar automated container terminal engineering.

Abstract:Navigation lamp is usually set at offshore breakwater head to ensure the safe navigation of ship,however,as the basic structure of navigation lamp pile,there is no code or handbook can be referred for the design of foundation and maintenance channel.In this paper,design of navigation lamp pile foundation and maintenance channel for offshore breakwater is adjusted and optimized gradually based on the actual project.Then,a reasonable and feasible composite structure of navigation lamp pile foundation and maintenance channel for offshore breakwater is put forward.The composite structure comprehensively considers the overall stability of the structure under the action of wave,the influence to the artificial armor block installation due to navigation lamp pile foundation,the convenience of maintenance channel using,and the feasibility for the site construction.The composite structure of navigation lamp pile foundation and maintenance channel for offshore breakwater in this paper can provide a certain reference for the design of other similar port projects.

Abstract:Based on the present situation and development requirements of Xinhai Harbor，we establish the simulation model of the ro-ro dock harbor system to deal with the problems that whether the actual capacity of the ro-ro dock can meet the transportation demand,especially the adaptability of the pier capacity during the peak period.By simulating the operation process of ro-ro dock and the operation of it during peak hours under different working conditions,we explore the factors affecting the wharf’s throughout capacity.According to the research,insufficient consideration of the impact of the water area condition and the vessel operation on the wharf capacity will result in that the capacity of some newly added terminals cannot be fully utilized.It is suggested that in the similar project planning and construction,the research on the coordination of the channel capacity,the port capacity,the terminal capacity and the onshore supporting facilities should be strengthened to ensure that the capabilities of each system can be fully utilized.

Abstract:At present,China’s port engineering construction has entered a new period.The scale and the investment of the project are large.At the same time,it also faces problems such as complex natural conditions,tight construction period,and complex construction procedures.In the case of diversified construction mode,ensuring the smooth implementation of the project is the fundamental requirement of the construction unit.Aiming at the problem of how to effectively carry out risk control in port construction,this paper makes a comparative analysis of the different construction modes,uses the analytic hierarchy process to establish a quantitative analysis model,and constructs the judgment matrix and consistency check,finally gets the optimal choice which meets the requirements of the construction unit for system target decision and risk control.

Abstract:Bank collapse caused by scouring occurs frequently in the middle and lower reaches of the Yangtze River and leads to huge damages.In order to search the mechanism of bank collapse happening in the straight river section,we carry out the observation and analysis by means of simulation experiment.There are five main kinds of currents with different movement characteristics in the process of bank collapse.Crescent sand waves，lying near the surface of water，are important transport carriers for sediments and may lead to sustained and formative of bank collapse.The aboved opinions are approved by slope protection simulation experiment.Comparing to protecting the toe area,protecting the area near the surface of water is more conducive to effectively controlling bank collapse from the engineering point of view.Meanwhile,reasonable protection of toe area is necessary to avoid continuous erosion of unfavorable influence to slopes in the future.

Abstract:Concerning the layout of culverts,outlets and energy dissipation facilities of the filling-emptying system of longitudinal culvert in lock floor,we carry out a lot of theoretical analyses and physical model tests based on the lock engineering.According to relevant research results,we analyze the main characteristics and applicability of the filling-emptying system of longitudinal culvert in lock floor,and put forward the improved layout of energy dissipation system for promoting the efficiency of ship lock and optimizing the force of mooring ship.We also give suggestions on the application of the filling-emptying system of longitudinal culvert in lock floor in the medium & high-head lock project.

Abstract:The water damage of riprap spur dike in waterway regulation buildings is very serious and its reliability and service life are difficult to predict accurately.In order to solve this problem,the combination of flow process and maximum impact depth is studied experimentally and numerically through flume physical model test with unsteady flow process as control condition.The failure criterion of riprap groves is defined and the probabilistic model calculation method of the combination of flow process and maximum impact depth is obtained by using basic statistical theory.This method can be used for reference to improve the reliability of waterway regulation buildings,and can also be used as a reference for waterway management departments.

Abstract:Aiming at the problem of landslide collapse in the foundation pit slope of the bank protecting structure in the waterway regulation engineering,taking the waterway regulation engineering of a route in northern Zhejiang Province as an example,the stability of the slope of this project is compared and analyzed by using the traditional article points method based on the traditional limit equilibrium theory and the numerical simulation FLAC3D method.The FLAC3D method is more perfect than the article points method in terms of analysis conditions and more reliable in theory.It can also analyze area of the slope in detail for targeted prevention.The calculation theory of article points method is ideal,and the result is conservative.

Abstract:If the Baima junction lock for resuming navigation project in Xiujiang River is designed as the conventional single-step lock,the flow supplied by the river will be less than the water consumption of a navigation lock during the dry season,and cannot meet the water demand for lockage.Based on the research achievements and experiences at home and abroad,we propose a layout scheme of filling and emptying system with two open water saving basins,calculate and analyze the corresponding hydraulic characteristics with various valve opening and closing schemes by one-dimensional mathematical model,and obtain reasonable valve opening and closing schemes,water saving rate and hydraulic characteristics of lock chamber.The results show that,in the case of an optimized valve scheme,the filling and emptying time is controlled within the range of 12 minutes,and the water saving rate is at least 49%.The proposed schemes of water saving lock can deal with the lack of water during the dry season.

Abstract:During long-term operation,the natural branching channels appear some problems frequently such as sediment accumulation,channel deformation and shoal scouring in the rear area of the mouth area etc.Taking the natural branching channel as the object,we design a kind of channel regulation structure innovatively named wild goose-shaped diversion dam with the idea of ecological water conservancy,and carry out the experimental research and analytic demonstration about the feasibility of the wild goose-shaped diversion dam.Compared with the traditional fish-bone dam,wild goose-shaped diversion dam has better performance in water diversion and sediment discharge.Through a series of calibration experiments of position arrangement and structure,the application of wild goose-shaped diversion dam in practical engineering is optimized.The channel regulation scheme of wild goose-shaped diversion dam is feasible in technology,economy and stability by demonstrating,and the wild goose-shaped diversion dam can also be applied to river and lake renovation works,and the same to the landscape engineering with relevant requirements.

Abstract:Aiming at the problem that the large ship lock is easy to generate temperature cracks due to improper temperature control and destroy the overall structure,we apply the method of temperature stress simulation to research the problem.Taking comprehensive factors such as the influence of concrete performance,boundary conditions into account,combined with the APDL language of ANSYS for secondary development,we write the thermodynamic parameter command flow to analyze the transient temperature field and stress fields of the lower gate of the Honghua second ship lock.The results show that the temperature can be effectively controlled by reducing the pouring temperature and the water passing measures.The process framework for calculating and controlling the large volume coagulation temperature stress is summarized,which can be used in actual engineering.

Abstract:If the dam-front water level of the open junction is adopted in the design of the upstream lowest water level of the medium & low-head canalized junction,the following problems easily arise:the lower bottom elevations of the upstream approach channel and threshold on ship-lock not only enlarge the wall section and increase the cost,but also easily lead to siltation;the flow pattern of the upstream and downstream channel entrance area is poor,so it is difficult to satisfy the requirements of ships’ safety entry and exit.Based on several engineering examples and according to the results of integral hydraulic model test,this article analyzes the rationality of using the dead water level of the junction as the upstream design lowest navigable stage through hydrological calculation and comparison of the navigation flow conditions,the navigation guarantee rate and the project investment.At the same time,combining with the backwater analysis of different operation modes of the junction,it is concluded that the water level connection between the upstream and downstream cascade of canalized river can meet the requirements when the junction run with dead water level and it is feasible to use the dead water level of the junction as the upstream design lowest navigable stage.

Abstract:The condition of the flow at the lock entrance area affects directly the safety of the ship in navigation.To counter the problems such as the poor flow condition and the big transverse velocity at the entrance area and connection segment in Likou hydro-junction,we put forward optimization measures including setting shallow dam on the upstream of the dam axis,adjusting the river regime and building guiding dikes for flow diversion based on the establishment of the integral hydraulic model test.The result shows that the flow regimes of the entrance area and connection segment are obviously improved by optimization measures,and the navigation flow condition meets the requirement of the specification.The ship model navigation experiment shows that the maximum navigable flow Q20%=4 661 m3s.The feasibility of engineering and safety of navigation under this plan is also demonstrated.

Abstract:The evolution characteristic of long-straight section channel often appears the unsteadiness of the beaches and the thalweg in the changeover portion,which causes the change of navigation channel.Taking a typical long-straight section channel named Mayangtan in the downstream of the Hanjiang River as an example,and based on the analysis of river evolution,model test and regulation effect before and after the regulation project,we summarize the experience of the long-straight section channel regulation project in the downstream of the Hanjiang River.The results show that,for the unsteadiness of the beaches and the thalweg in the long-straight channel,we shall plan reasonably the channel axis and take engineering measures to create micro-bend regulation lines,so as to stabilize effectively the navigation channel.When a lower regulation water level is adopted,by narrowing the width of regulation lines and the distance between regulating structures,the purpose of improving the channel scale of the transition section can be achieved.

Abstract:In order to improve design efficiency and statistical accuracy of excavation volume in dredging design of waterway engineering,we develop a 3D aided dredging design system for waterway engineering based on partial achievements of harbor investigation and design application system(HIDAS).The system combines 3D geological model and 3D CAD technology,and provides multiple functions including parametric intelligent modeling,automatic statistics of excavation volume,generating batch excavation section drawings and so on.We apply this system to the dredging design process in the expansion project of east channel of Qinzhou port,and achieve that the design sections can be generated automatically with different excavation slope ratios and different extra-deep and wide parameters according to different soil quality,excavation volume,extra-deep and wide excavation volume of different sections and different soil classification can be calculated separately,excavation section drawings with CAD format of different sections can be generated batch automatically.The system can greatly improve the design efficiency and quality.

Abstract:In the view of the lack of experimental verification of the 3D imaging sonar-related detection indicators,we carry out an indoor model experiment to explore the effects of different-sized cube and cylinder test blocks,different boundary media and defective cylindrical stakes on 3D imaging sonar.The reseult shows that the 3D imaging sonar system can effectively identify objects of different shapes in centimeters;when scanning for smooth and hard objects,the acoustic signal will be specularly reflected and the effective data cannot be obtained;the defects of 5 cm and above can be effectively identified.The research result may serve as reference for the practical engineering applications.

Abstract:Aiming at the car-dumper system’s difficulties in complexity of loading and unloading process,interference between equipment and pipeline,compact indoor layout and narrow construction work surface of the railway-river combined transportation in the upper Yangtze River,we carry out the application research of collaborative design of multi-profession,interference checking,simulation analysis,dynamic delivery and construction control application by the BIM technology,explore the technical route of the BIM implementation in the large bulk cargo project and put it into practice to provide a reference for the BIM application of similar projects.The analysis shows that the BIM technology can be closely integrated with complex engineering projects to improve the efficiency and quality of the design and construction and guide the project implementation and cost control.The potential in the water transportation industry is worth exploring in depth.

Abstract:Pile bearing stratum is one of the key factors affecting the bearing capacity of foundation pile.Coral reef limestone is hard and brittle with uneven distribution of soft and hard,which is quite different from the traditional rock and soil types,and brings great uncertainty to the design and construction of pile foundation.It is not reliable to use the traditional pile foundation design theory to determine the construction pile length and bearing layer plan.Therefore,in the stage of pile test,the bearing characteristics of steel pipe piles in different bearing stratum are studied by means of high strain dynamic test and static load test.The results show intuitively that highly weathered coral-reef limestone of which the SPT numbers are up to 80~＞ 100 should be selected as the pile end bearing stratum in this kind of engineering geology.

Abstract:The large sand bag embankment,as a new technology for the construction of the embankment on soft soil foundation,has improved the cohesive force and integrity of the embankment and can better adapt to the deformation of the soft soil foundation.The whole mechanics and engineering characteristics of the large sand bag embankment have been changed greatly under the action of bag body.It is the basis of embankment simulation and design calculation to reasonably determine the mechanical and engineering characteristics of the sand bag and determine its influence on the overall stability of the embankment.This paper analyzes the research status of the function of bag body in large sand bag embankment,and summarizes the research results and progress of three aspects of model test,numerical analysis and theoretical deduction.At last,the pertinence suggestion is put forward to the engineering application and the future research direction.

Abstract:Aiming at the problem that the time limit of reinforcing fresh hydraulic reclaimed mud with secondary treatment technology is short but the construction cost is high,a new one-time treatment technology of vacuum preloading for dredged silt foundation is put forward.Three key technologies are introduced in detail from the aspects of construction process,technical parameters,material performance parameters and key points of construction:new type of large-area sand bedding,new type of vacuum preloading drainage system and graded vacuum preloading technology.Based on the general analysis of the reinforcement effect and the direct construction cost of the technique,the results show that the reinforcement effect of the technique is better and the relative cost of the secondary treatment technology is significantly reduced.

Abstract:The proposed construction site of heavy cargo wharf of Xiapu nuclear power plant in Fujian Province has an ultra-thick soft soil layer of 40~50 m.The pile-soil interaction of ultra-long friction piles used in wharf foundation is more complex than that of short piles and middle long piles,and many problems belong to the critical fuzzy range of the design code.The displacement,internal force and side friction of ultra-long piles under horizontal and vertical loads are calculated and analyzed by finite element method.The distribution trend of horizontal displacement and internal force of ultra-long friction piles in ultra-thick soft soil is summarized.For ultra-long friction piles,it is more reasonable to provide layered side friction for the same soil layer,and the side friction under 50 m mud surface will continue to increase with the depth of soil layer,and the growth rate is faster than that above 50 m.

Abstract:The final set,bearing stratum and ultimate pile capacity of the driven pile are critical for the quality control of piling works.Carrying out the whole highstrain dynamic testing to study the driving behavior of open steel pipe piles with different wall thickness in coralreef limestone,including significant parameters such as the pile capacity,set,driving stress and energy transfer in pile driving and analyzing the characteristics of 480 driven piles,we draw the conclusion as follows:the bearing stratum shall be highly weathered coralreef limestone and the final criterion shall be controlled by the final set and embedment depth of piles in the highly weathered rock.

Abstract:For the design and application of the jet grouting pile in stabilizing the slope,combining with the upgrading of a wharf using the jet grouting pile reinforcement,we compare the PLAXIS based on the strength reduction method and the GEO-SLOPE calculation method,and propose the PLAXIS for the slope strengthening by the jet grouting pile,which is more adaptable.According to the results of on-site sampling test,the average compressive strength of the jet grouting pile in silty clay can reach 6 MPa,the average internal friction angle is about 30°,and the average value of the cohesive force is about 0.5 MPa,which meets the design requirements.Therefore,the application of the jet grouting pile in the upgrading of the wharf is reasonable.

Abstract:As a cause of special marine geotechnical medium,the frame work structure of coral-reef limestone is in stratum soft and hard interacted,of which the breakable particles are more porosity and irregular in shape.These characteristics of coral-reef limestone cause significant difference compared to the conventional geomaterial,and steel pipe pile driving is lack of practical experience in this ground condition.When and how to stop the hammer is difficulty in the construction of steel pipe piles under reef limestone geological conditions,so we discuss the key control points of pile driving from some aspects,such as the standard penetration test,soil laboratory test,pile driving parameters and high strain pile test.We propose that embedded depth in limestone should be added as dominant control factor,and driving in sub-regional strategy can improve the work efficiency.Standard pile length of each region can be determined by high strain pile test,which is used as guidance for this region.

Abstract:In view of the common quality problems of precast core column rock-socketed steel pipe pile,such as rolled edge of steel pipe pile,stuck drill and eccentric reinforcement cage,the causes and effects are discussed.We adopt methods for quality control which includes reasonable control of steel pipe pile penetration degree and other standards for pile sinking,pile tip using external reinforcement,improved hammer and other methods.The quality of precast core column rock-socketed steel pipe piles before and after construction improvement in the first phase of Wuhan Xingang Sanjiang port area integrated wharf project is compared and verified.The results show that the control standards for precast core column rock-socketed steel pipe piles should not be too strict.At the same time,it is suggested that the external reinforced steel pipe pile tip should be adopted in the design,and the cylindrical punching hammer should be used in the construction to effectively solve the problem of drill sticking in the construction process of pile foundation.The improved hammer or the hydraulic drilling method can effectively improve the quality of precast core column rock-socketed steel pipe pile (inclined pile）.

Abstract:Aiming at the construction cofferdam standard of ship lock expansion project,we analyze double functions of the cofferdam based on Zhuzhou second ship lock project.The standard of cofferdam should be determined for different regions.Based on fully balancing the construction cost of diversion facilities and the loss caused by reducing standards,the flood control and storm water drainage are appropriately implemented to minimize the impact on the duration of the project.Meanwhile,we summarize the characteristics of construction diversion,the design targets of the cofferdam and the flood control measures,which can provide references to new arrangement schemes and cofferdam design for ship lock expansion project.