Abstract:To compare and analyze the wave-eliminating performance of the flat-arc-plate and the twin-flat-plate permeable breakwater structure under different incident wave conditions，we carry out an experimental study of the wave and its interaction based on the physical model test. The results show that the transmission coefficients of the flat-arc-plate and the twin-flat-plate transparent breakwater both fluctuate and decrease with the increase of the relative plate width，while the energy consumption coefficient is opposite. Under different diving depth conditions，the transmission coefficient and reflection coefficient of the flat-arc-plate transparent breakwater are both smaller than that of the twin-flat-plate transparent breakwater，and the transmission coefficient can be reduced by up to 22%. When the relative board width W/L=0.103，the maximum reduction in reflection coefficient is 82%. The energy consumption coefficient of flat-arc-plate permeable breakwater is greater than that of twin-flat-plate permeable breakwater. The relative W/L between the plates is in the range of 0.103 to 0.212，and the average increase in dissipation coefficient is about 22%. The research results r can provide necessary theoretical guidance for the application of the two permeable breakwater structures in engineering. It is recommended to choose the flat arc slab permeable dike in the actual project.

Abstract:We carry out the ground penetrating radar forward modeling for three layers of air，cofferdam and silt on the basis of finite difference time domain，and analyze the radar wave propagation process and typical receiving patterns.The results show that the radar wave propagates in the form of spherical wave in the medium，and the energy disperses gradually with the propagation distance. When it encounters the interface with different electrical properties，reflection and transmission will be generated.The interface between the riprap layer and the soil layer can be inferred according to the radar reflection and the continuous characteristics of the in-phase axis，and the weak abnormal areas such as suspected mud impregnation can be delimited according to the abnormal reflection of the waveform，reversal waveform and the slow wave velocity. However，the receiving graph is distorted by multiple echoes，which is easy to cause misjudgment.By applying the ground penetrating radar to the actual riprap cofferdam project and combining with the borehole survey，the distribution of riprap layer thickness and the anomaly in riprap body are found out.

Abstract:Aiming at the huge wave energy generated by wave motion，we design a wave energy conversion model composed of Savonius rotor and a double-buoy floating breakwater. In order to study the energy capturing and wave elimination performance of the new type of breakwater，we optimize the parameters of the model structure，obtain the optimal water penetration depth of the model by data interpolation on the basis of the experimental data，then test the model under different incident wave heights and different wave periods，analyze the measured capture power coefficient，transmission coefficient and other data，apply the STAR-CCM+ software for numerical simulation on the basis of the theory of viscous fluids，and compare with the physical experiment results for verification.The results show that the model has the best wave elimination performance when the energy capture performance of the model is in the best range，which means that the model successfully captures and transforms wave energy. The variation trend of the simulated data is basically consistent with the experimental data，and the differences of data are within the error allowable range.

Abstract:In the estuary area with heavy wind waves，polyurethane bonded aggregate（PBA）revetment is applied to the dams. By theoretical research，on-site monitoring，and physical model test，this paper studies structural stability，wave force distribution，and wave damping of PBA revetment. The results show：1）Under significant wave height of 2.0-3.0 m，PBA revetment with thickness of 20-30 cm remains stable when the slope ratio is 1:2. 2）PBA revetment can effectively reduce wave run-up with a designed roughness coefficient of 0.80-0.85. 3）The maximum wave pressure is not less than 0.5ρgH（the product of seawater density，gravitational acceleration，and wave height）.

Abstract:In view of the problems of land occupation and environmental pollution for Chaohu slit treatment，as well as the impact of engineering construction on the environment，we study the dewatering，solidification and tube filling of Chaohu silt using the geotextile tube technology. Taking the volume，density and supernatant of the flocculant as the evaluation indices，we use the single factor analysis method to conduct the flocculant pilot tests design and result analysis. The results show that the flocculant based on cationic polyacrylamide is suitable for the treatment of Chaohu Lake silt dewatering effect，the optimal dosage of 0.5% concentration of flocculant is 1 mL/100 mL mud in Chaohu，and the optimal dosage of curing agent is 10% of the dry weight of Chaohu Lake silt；the Chaohu Lake silt filling rate is 0.8-1.0 m3/h，the flocculant filling rate is 1.0-1.2 m3/h，and the curing agent filling rate is 0.08-0.10 m3/h. The test results show that the total phosphorus（TP）in the filtered water is significantly reduced，the dewatering and solidification treatment of silt will not cause extra pollution to the surrounding environment，and the use of geotechnical pipe bags for sludge dewatering is safe for environmental protection.

Abstract:In view of the deep stirring treatment of soft foundation mucky soil in a certain waterway engineering，we study the effects of geopolymer with fly ash（FA）and slag（S）on the properties of mucky soil. Geopolymer and conventional amendments of 10%，20%，and 30% are added into field mucky soil，and specimens of different moisture contents are prepared. Unconfined compressive strength（UCS）tests，flexural-tensile modulus tests，and scanning electron microscope（SEM）imaging tests are carried out to evaluate the characteristics of mechanical property and microstructure changes of the improved soil and thereby obtain a reasonable amendment amount. The following observations can be drawn from the results：1）Geopolymer improvement with FA+S and alkali activation solution contributes to a more compact soil microstructure and significantly improves the strength and stiffness of the mucky soil. 2）Considering the economic cost，the desirable amount of geopolymer amendment is 20%（5%FA+15%S），and its applicable moisture content range is wide，specifically 0.75 WL-1.25 WL.

Abstract:The “14th Five-Year Plan” period is a key strategic opportunity for Guangxi Beibu Gulf Ports to help build a new pattern of all-round opening and development from all directions and support the accelerated construction of a new development paradigm，in which the domestic and international circulations reinforce each other with the domestic circulation as the mainstay. The construction of the New Western Land-Sea Corridor，the integrated development of Beihai，Qinzhou，and Fangchenggang cities，and other national and regional strategies all put forward higher requirements on the development directions and construction priorities of Guangxi Beibu Gulf Ports during the “14th Five-Year Plan” period. In accordance with the overall deployment of the Outline for Building a Leading Transportation Nation，this paper focuses on a better integration into the national three-dimensional transportation network，greater support for the implementation of major national strategies，and superior services for the economic and social development of the hinterland and large-scale port-based industries. Attending to the general trend，taking a long-term view，obtaining a picture of the overall situation，and grasping the opportunities，it summarizes the current development characteristics and main problems of Guangxi Beibu Gulf Ports and puts forward overall thoughts and orientations for their development during the “14th Five-Year Plan” period.

Abstract:The mechanical characteristics of the large cylindrical structure with unloading plates are complex in practical engineering，and thus it is difficult to calculate by codes. Therefore，we build a model for this structure by finite element software to study its vertical tension，circumferential tension，vertical bending moment，circumferential bending moment，and the load distribution positions under the action of the quay crane load，wave force，and loading earth pressure. The results show that the load of a quay crane has little influence on the stress distribution of the whole structure of a large cylinder but has a significant impact on the bending moment at the top of the cylinder. The top of the cylinder is greatly affected by the vertical bending moment，while the lower cylinder is greatly influenced by the circumferential bending moment. Under the three kinds of loads，the maximum vertical and circumferential bending moments occur at the joint between cylinders，and the lower cylinder is under tension on the wave side and compression on the soil side.

Abstract:In view of the structural design of a small emergency berth engineering wharf in Panjin，we consider the natural conditions of the area where the project is located and the characteristics of the design ship types for the wharf，and determine the wharf structure and pile foundation suitable for the project according to the domestic codes and previous engineering experience. We also summarize the key structural design points for small wharves in areas with large tidal ranges，various ship types，large seismic inertia forces，and severe ice conditions. The results show that the high-piled beam-slab wharf has better adaptability to shallow sandy geology. The steel pipe pile foundation with multiple fork piles can meet the requirements of wharves for load-bearing capacity and seismic and ice resistance. The double-layer mooring platform is equipped for the safe mooring of different types of ships in the case of large water level differences. The ice load can be effectively withstood by an angular shape on the ice-facing surface of the prefabricated walkway slab of the lower mooring platform.

Abstract:The development status and existing problems of the Beibu Gulf Port in recent years are evaluated. The implementation of the “One Belt，One Road”，the Western Development Drive，and other strategies is investigated. Then，we center around the “three major positioning” given by the state to Guangxi Autonomous Region and summarize the great strategic significance of building an international hub seaport and an international gateway for the new western land-sea corridor in the Beibu Gulf Port in the new development stage. According to the economic development situation of the hinterland，we analyze the future development demands of the Beibu Gulf Port and predict the future transportation demand scale of the port with the combined forecasting model. From the national strategic perspective，we put forward a development idea of “strengthening the hub，unblocking the corridor，cutting costs，improving services，and gathering factors” and build a functional system of “1 hub，2 networks，and 3 districts” for the Beibu Gulf International Gateway Port. Finally，we sort out the key tasks and relevant suggestions for the construction of the port in the near future，focusing on facility construction，improvement of collection and distribution channels，promotion of logistics services，and port industrial agglomeration. This research holds important guiding significance for the construction of international gateway ports in the future.

Abstract:Karachi Port is the largest seaport in Pakistan which is located on the southwest of Karachi City and it is the east end of the China-Pakistan Economic Corridor. The Karachi Port development is facing problems such as prominent port-city contradictions and busy transportation channels. Based on the analysis of current situation of Karachi Port transportation channels，we predict the volume of collection and distribution through Karachi City，and propose four channel options of port access road，coastal railways，coastal roads，ML-1 railways and port railways. Different combination solutions are discussed combined with Karachi Port and Karachi City development：1）port access road + ML-1 railway and port railway reconstruction；2）port access road + coastal road；3）coastal road + ML-1 railway and port railway reconstruction；4）coastal railway；5）coastal railway + coastal road. After comparing and selecting each combination option，the comprehensive solution is proposed，which may serve as reference for similar projects.

Abstract:For swell dominated sea areas，no matured and detailed general layout design method for sea port engineering exists in domestic and foreign codes. Taking a specific sea port in Gulf of Guinea as an example，based on the owner’s requirement of the project’s downtime ratio shall be less than 1%，we investigate the 23 years hindcast time series data of concurrent wind，wave，tide，and current following the basic principles of layout arrangement in the international codes and guidelines，and optimize the general layout arrangement by the means of numerical wave model，ship maneuvering and mooring analysis，under keel clearance analysis for the main design vessels. The results show that the optimized layout scheme has the advantages of user friendly，short construction period and low cost，which can be used as a reference for the similar projects.

Abstract:Due to the particularity of the goods，the collection of wastewater in the container yards of dangerous goods has attracted much attention from all parties. Taking the dangerous goods container yard of a port in the Middle East as the background，we determine standards for the initial rainwater volume，the fire accident sewage volume，and the effective volume of the wastewater tank under different standard systems for the dangerous goods container yard. The design ideas in China and abroad are compared. The wastewater tank adopts the intercepting mode of overflow weir and is equipped with pH meter，thermometer，as well as VOC and HAL concentration detector. It realizes the intercepting mode with an automatic alarm. At the same time，suggestions for improvement are also put forward for the deficiencies of the project.

Abstract:Regarding the relocation and site selection of Karachi Fishing Port，this paper adopts a multi-factor comprehensive evaluation method to analyze and evaluate four alternative port sites for port site recommendation. In view of the characteristics of fishing ports，we should consider the convenience of transportation between a fishing port and the concentrated residential area of fishery workers as well as the impact of the fishing port on the surrounding environment when analyzing the location of the fishing port. Moreover，the relationship with the planned land use and the environmental impact on the planned area must be involved for the consideration of coordination between site selection and planning of a fishing port. Finally，this paper provides methods for the quantification of all factors involved in site selection for reference.

Abstract:With the latest river section data，we build a one-dimensional unsteady flow model of the Xiangjiaba-Luzhou reach，and analyze quantitatively the scheme of the minimum navigable flow and corresponding daily-regulated outflow for the Xiangjiaba Hydropower Station under ensured normal navigation during the impoundment period of the Baihetan Reservoir. Specifically，with assumed steady lateral inflow from Hengjiang River（70 m3/s）and Minjiang River（700 m3/s），we simulate the outflow from the Xiangjiaba Hydropower Station at different orders of magnitude and calculate the water level at each section along the way. The lowest navigable water level in the downstream below Xiangjiaba obtained is 265.8 m，and the corresponding flow is about 1 520 m3/s. Then，according to the daily peak shaving operation law of the station，the discharge flow is increased to a steady outflow of 1 700 m3/s during the day and reduced to 1 520 m3/s at night. As a result，the maximum water level variation is 0.31 m，which has little impact on the downstream ships. When the discharge flow is 1 700 m3/s，the width of 2.5 m water depth can be widened by about 20 m on that under the discharge flow of 1 520 m3/s. This method can alleviate the load reduction pressure on cross-dam transportation ships.

Abstract:The river shipping demand forecast is the core issue of shipping planning and construction. This paper introduces the concepts of industrial structure coefficient and freight intensity，and analyzes the correlation between freight volume and economic industrial structure of the three golden waterways of the Yangtze River，Rhine River and Mississippi River. The results show that the correlation between freight volume and elasticity coefficient and GDP decreases with the optimization and adjustment of economic structure. The growth rate of elasticity coefficient and freight volume tends to decrease with the increase of industrial structure coefficient，but the correlation is poor；the freight intensity is larger when the industrial structure coefficient is smaller，and the freight intensity decreases with the increase of industrial structure coefficient. The regression analysis method is used to establish the exponential function relationship between freight intensity and industry structure coefficient. Therefore，the correlation between freight intensity and industrial structure coefficient can be used for river shipping demand forecasting，and the influence of industrial structure coefficient can also be considered in selection of economic indicators. The research results provide a support for the forecast of inland river shipping demand growth such as the Yangtze River.

Abstract:The gear-type mixture embankment is a new concrete structure adopted in the first phase of the deep-water channel project on the Yangtze River，and the relevant study is still in an early stage. To analyze its mechanical features and expand its application in later engineering，we numerically analyze the impacting factors for the current force over the gear-type mixture embankment by the CFX software. The results show that the current force over the gear-type mixture embankment is composed of the hydrodynamic pressure and the hydrostatic pressure difference between the front and the back of the embankment body. The current force grows as the incident velocity，incident angle，and relative embankment height increase. The force and the incident velocity manifest an approximate square relationship when the velocity is small. When the incident velocity exceeds a certain limit，the current force and the velocity are in an approximate proportional relationship. A sensitive value is observed for the impact of the relative embankment height on the current force whereby the height has a larger impact on the current force when it is near the sensitive value.

Abstract:To solve the layout and height adjustment of shore beacon suitable for large variation of water level in the Three Gorges reservoir area，a novel type of self-floating lift navigation mark is proposed. Aiming at the influence of structural design and environmental load on motion characteristics of this navigation mark，a 3-D hydrodynamic model based on MOSES（multi-operational structural engineering simulator）is developed，and the heave responses of the structure under wave action and combined action of wind，wave and current are studied with different drafts and depths. The results show：1）Improving the motion responses by the increase of draft is limited. The motion characteristics of the structure are optimal at 1.0 m draft.2）The greater the water depth，the better the motion characteristics. 3）The motion characteristics under the combined action of wind，wave and current are better than those under the action of wave.

Abstract:Nangang industrial zone in Tianjin is located on a typical muddy coast in Bohai Bay，and an inner branch channel connecting to the Dagang channel is proposed to be built in its eastern basin. To predict the siltation of the channel，we establish a numerical model of sediment transport coupling with wave-current interaction，choose the spring tide data measured at the site as the representative tidal and the energy-weighted average of measured wave data from nearby observation station as the representative wave，and verify the model by the annual siltation data of the adjacent 150，000-ton waterway of Tianjin Port. On the basis，we apply the numerical model to calculate the sediment transport of the sea area of Nangang industrial zone，and predict the annual sedimentation along the branch channel of the east basin. The results show that the siltation mainly occurs in the entrance section of Nangang industrial zone and the first half part of the branch channel in the east basin.

Abstract:A junction lock is the main control project for the navigation engineering of the involved reach，and its construction plays an important role in the channelization of the river. Due to the large scale of the lock chamber，the high working head，and the high water delivery energy，solving hydraulic problems in water delivery is the key link of lock design. To ensure that the ships and locks meet relevant requirements in water delivery，we probe into the hydraulic characteristics，berthing conditions，and flow conditions of approach channels during water delivery on the basis of tests by a physical model with a scale of 1:30. The results show that under the recommended arrangement of the water delivery system and valve opening mode，all hydraulic indexes can meet the requirements of the codes and design.

Abstract:The second-line ship lock of the Xiangqi Junction on the Xiangjiang River is an additional second-line ship lock on the shore of existing buildings，resulting in a curved connection between the approach channel of the second-line ship lock and the main channel. Due to the limitation of the approach channel of the first-line ship lock and the short wheelbase between the first-line ship lock and the second-line ship lock，the navigable flow conditions in the upstream and downstream entrance areas and connecting sections of the proposed second-line ship lock are relatively complicated. Therefore，relying on the expansion project of the second-line ship lock of the Xiangqi Junction，we conduct a 1:100 fixed-bed physical model test on flow to analyze the navigable flow conditions at the entrance area of the downstream approach channel of ship locks. A series of experimental studies are carried out on the optimization of the opening method of the sluice lock，the optimization of the dike of the downstream approach channel of the second-line ship lock，the optimization of the embankment on the right bank downstream of the power station，and the local dredging of the river channel downstream of the outlet of the power station. Moreover，optimization measures are proposed to improve the navigable flow conditions.

Abstract:Longmen port area of Taizhou Port is an important part of Taizhou Port “One-Port Six District”. In the scale and level restriction of the approach channel，most of in-and-out port ships need to wait for the tide. Therefore，when setting up anchorages in the Longmen Port Area，both of the number of anchoring points for waiting berth and the number of waiting for the tide need to take into consideration. There is no recommended method to calculate the number of tide anchorage and anchoring points in the industry. This paper studies the anchoring points in Longmen Port Area according to the relevant research and standard. Using the theoretical analysis method of queuing theory，the number of tide anchorage and the number of anchoring points in Longmen Port Area are comprehensively measured，and the setting scheme of the number of tide anchorages （waiting for tide or waiting for tide+waiting berth）is obtained. That is to say，under the condition of consistent assurance rate，the number of anchoring points can take the larger of the number of waiting berth and waiting for the tide.

Abstract:The Qingshan hydro-junction reconstruction project on the Lishui River is mainly to build ship locks and structures for water retaining and discharge after demolishing the original buildings on the left branch. To tackle the problems in flood discharge capacity and navigation of the hydro-junction involved in the general layout plan of the Qingshan hydro-junction reconstruction project，the paper studies the general layout and flood discharge capacity of the hydro-junction and the navigation conditions of the entrance area in the ship lock. A general physical model is adopted for tests，and a comparative analysis is carried out on the discharge capacity and navigation conditions of the current situation and the design scheme of the hydro-junction. In this way，the original design scheme is optimized. The results show that the discharge capacity of the hydro-junction is close to the current situation；when the main flow of the left branch deflects to the middle and right part，the navigation flow conditions in the entrance area of the ship lock are improved. Therefore，we recommend demolishing the original left branch buildings，moving the axis down 300 m，building a sluice with eleven holes，reducing one-hole sluices to connect the dam section，and changing the left two-hole sluice to a two-hole spillway dam. The recommended scheme is feasible，and the navigation conditions in the entrance area are significantly improved.

Abstract:In view of the substantial increase of beach risks needing regulation in the upstream channel of the Datengxia hydro-junction due to the change of the operation mode of the hydro-junction in the project proposal and feasibility study stage，we analyze comparatively the lowest navigable stage under the two operation modes and the construction water level before and after the first-stage impoundment，and obtain the lowest navigable stage and the decline caused by excavation，the influence on the channel design scheme and investment，and the construction water level results before and after the first impoundment of Datengxia. The conclusion is that the channel regulation scheme in the reservoir area is greatly affected by the operation mode of the hydro-junction. In the design，the influence of dispatching operation mode on the design water level and design scheme should be analyzed emphatically. Combined with the water storage plan of the hydro-junction，the land reef blasting operation should be reasonably arranged before the water storage to control the investment.

Abstract:Qingfeng hub is located in the middle reaches of the Cao’e River. In order to meet the needs of upstream water transportation，it is necessary to rebuild the existing Qingfeng hub and build a new ship lock. The discharge direction of the sluice gate of the hub is oblique to the downstream approach channel of the new ship lock，which makes the downstream flow conditions of the ship lock more complex and the navigation conditions relatively poor. In order to ensure the normal navigation of the downstream approach channel of the ship lock，a plane two-dimensional mathematical model of the middle reaches of the Cao’e River is established and calculated，and its improvement effect on the navigation flow conditions is studied by arranging different diversion walls. The results show：1）The training wall parallel to downstream approach channel can better improve the flow conditions in the channel，and the improvement effect is 70%~90%. 2）Extending the length of the training wall can further improve the navigable flow conditions of the approach channel，and the improvement effect can reach 100%. 3）By diversion pier，the improvement of longitudinal velocity is more effective than that of transverse velocity，and the improvement effect of longitudinal velocity is 100%，while the improvement effect of transverse velocity is less than 2%.

Abstract:The river channel of the sharp-bend compartment corridor is sharp bend and the river surface is narrow. The turning angle of the channel at the top of the curve is large，and the mainstream flow velocity at the turning section is high. To counter the problem that ships cannot pass the turning section of the corridor，we carry out a study on channel regulation at the sharp bend section. By the method of normal fixed bed physical model test and combining with the ship model test，we obtain the optimal regulation scheme which combines dredging with adjusting course based on the analysis of the indices such as the water level along the course，the velocity of the midcourse，the transverse velocity of the channel and the ship model sailing parameters. The experimental results show that，in the navigable water area with the maximum navigable flow of 2 010 m3/s，the navigable flow conditions，such as longitudinal and transverse velocity，are improved，the ship’s curved track zone is reduced，and the two-way navigable ships can pass through the sharp bend section of the corridor smoothly. This study can provide reference for the regulation of waterway in similar sharp curve sections.

Abstract:Considering the problems of low data utilization rate，low management efficiency，and slow response to distress in traditional waterway engineering，we conduct research on the integration technology for multi-source time-varying heterogeneous data，build a public data model with unified javascript object notation（JSON），and optimize the problem of high redundancy in the traditional data processing method to improve the efficiency of waterway engineering data integration. A building information modeling（BIM）early-warning platform for waterway engineering is developed with the data integration technology so that the current waterway engineering status portrayed by real-time data can be displayed visually on the BIM platform. Data integration，BIM early warning，and other functions are implemented and verified by the 6 m-deep waterway regulation project（part I）in the Wuhan-Anqing section of the Yangtze River trunk line. The results show that the BIM early-warning platform for waterway engineering based on the data integration technology provides a solid guarantee for relevant personnel to predict distresses and issue timely early warnings and thereby contributes to more efficient and convenient waterway engineering management.

Abstract:Airborne lidar surveying and mapping technology has the advantages of vegetation penetration，strong flexibility，high precision，and safe operation. Unmanned aerial vehicle（UAV）needs no special take-off and landing field and features flexible operation，convenient transfer，and low cost. The combination of such technologies can quickly obtain the surface 3D point cloud data，which is widely used in many fields. In Phase II of the Heishazhou waterway regulation project，the UAV airborne lidar surveying and mapping technology is conducted multiple times in key local areas in different stages to obtain high-precision surface information. Combined with the underwater topographic data obtained from multibeam bathymetric surveying，the data of filling，siltation，collapse and scour are comprehensively analyzed and evaluated before，during，and after regulation. It guides the engineering design，construction，monitoring，and acceptance，which provides a technical example for similar engineering practices.

Abstract:In view of the problem that the reflected wave curve is complicated when a variable impedance pile is under vertical transient non-free end excitation，we build a simplified mathematical pile-soil vertical vibration model on the basis of the longitudinal vibration theory of one-dimensional viscoelastic rods and the soil plane strain model. We adopt the raised-cosine function to simulate the transient excitation force，obtain a semi-analytical solution to the dynamic response at an arbitrary position on the pile stem through matrix operation and integral transform，and compare with the measured low-strain data about offshore bored piles with long steel casings. The results show that the proposed method demonstrates the characteristics of the reflected signal at the end of the steel casing above the concrete top. Furthermore，combining the above method with the simulation of similar working conditions under design and construction parameters is conducive to analyzing complicated reflected wave curves produced by non-free end excitation applied to variable impedance piles and identifying the pile stem defects.

Abstract:Under the action of saturated water，the rock foundation of the port in the red bed area weakens in the anti-deformation and bearing capacity，which affects the stability of the port foundation. To explore the influence of water saturation on mechanical properties of rocks in red bed area，we take sandstone，argillaceous sandstone，and mudstone as research objects to conduct the water absorption measurement，Brazilian splitting，as well as uniaxial and triaxial compression tests. The results show that mudstone has the strongest water absorption，with an average of 0.505%. The average water absorption of argillaceous sandstone and sandstone is 0.435% and 0.414% respectively. The Poisson’s ratio of the three kinds of rocks increases after water saturation，indicating that the circumferential deformation is more sensitive than the axial deformation，and the volume expansion is more significant after water saturation. The tensile strength and the uniaxial and triaxial compressive strength of rock show different degrees of attenuation after saturation. The research results may serve as reference for the study on mechanical properties of water saturated rock and the bearing capacity of port foundation in the red bed area.

Abstract:At present，the formula for discriminating seismic liquefaction in foreign countries is mainly based on the simplified method proposed by Seed and Idriss，which compares the relationship between cyclic stress ratio（CSR）and cyclic resistance ratio（CRR）to determine whether liquefaction is possible. Historical seismic liquefaction data of in-situ tests are mostly utilized for fitting in the calculation of CRR，which makes the fitting formula of different scholars quite different. In view of the above differences，the in-situ test data of a foreign port project are selected in this paper，and a comparative analysis is conducted between the liquefaction discrimination method recommended by the US National Center for Earthquake Engineering Research（NCEER）and the discrimination method of Boulanger and Idriss. The following conclusions are drawn：1）The standard penetration test（SPT）reveals that the two methods have little difference in safety factors. The results of the cone penetration test（CPT）indicate that the method of Boulanger and Idriss is conservative. 2）The NCEER method has high reliability for predicting seismic liquefaction，while the method of Boulanger and Idriss has strong engineering adaptability. 3）In the design of relevant foreign projects，two or more methods should be used for calculation and mutual verification.

Abstract:As a new type of thin-walled prefabricated component applied in ecological environment improvement，the fish nest row can maintain the connection between the water body and the riverbed on the basis of sand protection and locally improve the underwater microbial environment，thereby playing an important role in protecting the Yangtze River. The fish nest row is constructed in the ecological conservation pilot area of the waterway regulation project（Section Ⅲ）in the Wuhan-Anqing section of the main line of the Yangtze River. Combined with the precise control of the construction，on-site observation of the drift of the fish nest row in water flow is carried out. It is compared and estimated based on the numerical model of the Morison equation and the empirical formula of drift distance. Finally，the numerical correction is made to the throwing construction of the fish nest row.

Abstract:Bottom mud of environmental dredging will be mixed with harmful pollutants. The disturbance effect produced by the traditional dredging cutters will lead to the diffusion of pollution sources and the poor dredging effect，so domestic environmental dredging projects urgently need dredging equipment suitable for construction requirements. Using the method of combining theoretical research and finite element technology，an environmental-friendly dredging equipment is designed. The finite element method is used to simulate and analyze the structural deformation and stress of the equipment under different working conditions，and the lightweight optimization of the machine tool is carried out. The research shows that：1）The wing gates and reamer sets of the new dredging cutter bear greater forces，so their strength and rigidity need to be strengthened. 2）The supporting parts are in better stress condition and can be lightweight design. 3）The force of the base part is relatively bad，and the base part needs to be strengthened.

Abstract:According to the working condition of super long spacing in the first stage construction project of Xiaomiaohong waterway extension project in Nantong Port，we analyze the the hydraulic characteristics of the ship and pipeline，such as the pressure head of mud pump，transmission resistance loss and etc，verify that the “2 pumps + 2 pumps” series construction technology adopted by the “Xinhaijiao” and “Hangjiaojie No.1” can ensure the construction demand of the super long spacing，and deduce the optimal construction position of “Hangjiaojie No.1”，which can solve the problem that the local discharge pressure is too high after the multi-stage mud pump series connection. We apply the results of process calculation and optimization measures to the follow-up engineering practice. The results show that the optimization improves the hourly interest rate and production rate of ship group，and achieves good construction effect.

Abstract:The floating regasification unit （FRU）of liquefied natural gas （LNG）adopts a mooring method with steel pipe piles and hoops to restrict its horizontal displacement and sustain waving force. The steel pipe piles are socketed into the seabed. This pile type is characterized by a thick pipe shaft，a great rock-socketed depth，a large diameter and hard construction. According to comparison and study on special programs，we propose the construction technology including building offshore construction platforms，enlarging piling holes，inserting integral steel pipe piles，presetting holes at the lower part of the steel pipes and casting underwater concrete. The technology helps well solve the problem regarding the integrity of concrete inside and outside the socketed pile and ensures the quality of the structure. It may serve as reference for similar projects.

Abstract:In view of the selection of anti-impurity equipments in the construction debris concentration area of the cutter suction dredger，this paper studies the structural designs，applicable conditions and construction process parameters of anti-impurity equipments，carries out the detailed designs of the structure of the anti-impurity equipments according to the type，the characteristics of the distribution area，and the size of debris，and obtain the application scopes of three kinds of anti-impurity equipments through the statistics of the construction parameters and production efficiency. The results show that when the cutter suction dredger constructions in the debris concentration area，choosing a reasonable anti-impurity equipment can minimize the impact of debris on ship construction and improve the economic benefits of the project.