Abstract:

Abstract:A 2D vertical finite volume model of tidal flow and sediment transport is established by laterally integrating Navier-Stokes equation. The orthogonal curvilinear grid is used, and actual topographic forms are generalized by jam technology of mesh, numerical equations is discreted using finite volume method, coupled equations of pressure force and velocity is solved by SIMPLER numerical modality.

Abstract:Two-dimensional tidal numerical model of tidal river in Yangtze River is built with unstructured grid, and the generalization of hydraulic structures is discussed to get precise result. Three tidal numerical models with different boundary condition (dry, water, flood) are built to test the conversation of flow, and the results indicate that the flow conversation of the tidal numerical model is favorable. In short, the tidal numerical model can simulate the tidal current effectively.

Abstract:In recent years, the toe-shooting method is widely applied to handling soft foundation of many offshore engineering projects such as building breakwaters, shore protections and reclamation of land from the sea as a commonly method. We analyze the impact on adjacent waters resulting from the blasting in the foundation of simulating the transport and diffusion process of the suspended sediment caused by toe-shooting method applied to the promotion and reclamation project located in Daishan. The result shows that the transport and diffusion of suspended sediment are predominantly affected by the current movement, the direction and scope of the former are determined to a great extent by the direction and dynamics of the latter. The content of suspended sediment rapidly decreases as a result of diffusion and silting. The content increment could basically reach the level below 10 mg/L within 3 hours after the blasting. The blasting has some impact on water environment of neighboring waters, but the duration is limited and the incidence is limited too.

Abstract:For the shipway exceeding the design service life, we shall carry out safety assessment to analyze the ship-building and repairing ability of the shipway. The assessment is to conduct checking calculation of the structural members under present working load, including the stress, reinforcement or displacement of the structure,combining with the site investigation and detection to carry out a comprehensive analysis. This paper expounds the safety assessment of shipway based on an example of shipway engineering, which may serve as a reference for the assessment of other structures.

Abstract:The tensile strength of an anchor system buried under the surface of the seabed mud increases gradually with the increase of backfill strength. In order to guarantee the safety of ship’s mooring, it is necessary to determine the tensile capacity growth of anchor system in the pit backfill. Using the calculating method of ABAQUS finite element software, we study the quantitative relationships between them combining with engineering examples.Adopting the temperature-controlling parameters’ reduction method and “three-step calculation” thinking, we obtain the formulae for the relationship between the two. With the actual strength of the backfill and undisturbed soil, we can calculate the tensile strength of the anchor system in a given period.

Abstract:This paper studies the existing prestressed concrete pipe’s stress measurement method using the mechanical stress release principle, and obtains relationship curves between drilling depth & diameter and different stress release levels by mathematical modeling. Furthermore, it presents the method for choosing reasonable drilling depth and diameter according to the structural characteristics and without injuring the internal main reinforcement,which is verified by corresponding site experiments.

Abstract:In construction of a wharf located in the Yangtze River in Wuhan, a vertical pile at the front row near water deviated 1.4 m, the part of which above the mud course had to be cut off for the follow-up construction,and another steel pipe pile with the same geometric dimensions was supplemented on the same site. The calculation was rather difficult and we solved the problem by CAD graphical method, which was proved feasible in practice.

Abstract:This paper studies the protection current distribution of impressed current cathodic protection (ICCP) for chloride contaminated reinforced concrete in the atmosphere zone. It seeks to master the main technical parameters of ICCP and applied to practical engineering. The layers and spacing of electrical connection steel rebar effect on the current distribution have studied in this paper. The results indicate that for the ICCP system which is applied to the chloride contaminated concrete of atmosphere zone, the first and second layers of reinforcement adjacent to the auxiliary anode absorbe more than 70% of total current, and their spacing has a great impact on the current dispersion in the steel reinforced bars.

Abstract:A comparative study is made on seismic design of port and harbor structures based on Chinese code, US guidelines and Japanese standards as well as guideline of International navigation association. This is the third of the series papers and the method for classification of site, evaluation of subgrade liquefaction, calculation of dynamic active and passive earth pressure acting on the structure in these codes are analyzed. It is shown that the methods for classification of site in these codes are similar but with different numbers. For evaluation of subgrade liquefaction,two step methods are used based on geological time, clay content and SPT counts in Chinese code. Soil shear stress method under earthquake excitation is adopted in US guideline. In Japanese code, a set of parameters based on uniformity coefficient, SPT, equivalent peak acceleration of ground motion and triaxial test are used for evaluation of subgrade liquefaction. For calculation of dynamic earth pressure, the Mononobe-Okabe equation or its modified formats are used in these codes.

Abstract:The current design code for dry docks was published early and it is not suitable for many modern large ships, so it is in an urgent need of revising. In view of the 300 000 DWT crude oil tanker，finite element models of standard section of hull and piers are built by ANSYS. This paper analyzes the distributional coefficient of lateral load in different conditions of gravity and ballast, makes a comparison with dry dock design specification.There are different characteristics on distributional coefficient of lateral load to reference for revising of dry dock design specification.

Abstract:Some structure design optimization measures for the gravity quay under special conditions are presented, such as setting special tail structure for the caisson, making the caisson overturn backward, adding strengthening the structure against overturning of the large cylinder, installing the slab against sliding at the bottom of the quay and setting the anchor structure for the gravity quay, etc., which have good adaptability and high application value.

Abstract:This paper gives a definition of high-piled wharf’s residual life intruded by chloride ions through an analysis on its whole process. Critical value of chloride ions in components is made sure based on the research at home and abroad. According to the theory of chloride ions’intrusion, we establish a prediction model of residual life about main components of high-piled wharf, and verify the effectiveness of the model by a practical example.

Abstract:Based on the analysis to the design of approach trestle for the large oil jetty in Daya bay in Guangdong province and similar practices, we research the forces on the trestle abutment, steel consumption, constructability and cost of a large oil jetty under different trestle spans, and summarize design characteristics of various trestle types, which may serve as a reference for similar engineering design.

Abstract:The management of the stack yard of bit dry bulk terminal is an important issue. Based on the stochastic service theory, we carry out a study on the dynamic changes of yard pile-bit, analyze the theory of the dynamic change of yard pile-bit, and establishe a yard pile-bit dynamic mathematical model by gridding the continuous space of the yard. On this basis, we establish a simulation model of the coal terminal logistics system which has a fine description of the dynamic change of the yard pile-bit. Moreover, we make a simulation test of an actual professional coal terminal, which verify the accuracy and applicability of the model.

Abstract:This paper introduces the design of steel frame for overhanging cone fender in Dalian port specialized ore terminal berth reconstruction project. In domestic port upgrading project, this structure is still the first utilized. According to the mechanical characteristics of steel frame for fender, we compared the two design schemes of steel frame for fender, and chose the radiation vertical board and top floor plan. The design method of steel frame for fender problems with solutions in installation process are also presented.

Abstract:Taking the 0.3 million DWT crude oil terminal and associated storage and transportation facilities project in Yangpu harbor of Hainan province as an example, this paper studies two throughout-life-cycle cathodic protection methods including sacrificial anode protection and impressed current protection from design, construction,latter maintenance and the whole life cycle cost.

Abstract:The circumferential variability of chloride penetration is analyzed based on the powder inspection collected from circular concrete column in Zhapu port. Then, the cumulative wind velocity, the cumulative wind pressure and wave pressure circumferential distribution at each direction of the circular concrete column are calculated according to the wind regime and wave conditions of Zhapu port. Also, using a grey analysis method, the correlations among the cumulative wind velocity, the cumulative wind pressure, the wave pressure and the surface chloride content, as well as the chloride diffusion coefficient are obtained. Finally, the research highlights the cumulative wind pressure which considers the Bernoulli effect and reflects a much real situation than cumulative wind velocity. The result of this research has a significant contribution to the similarity theory and durability evaluation system of seaport wharf.

Abstract:This paper summarizes the design idea of land general layout of Dachan bay container terminal phase I project, and discusses the key points of land layout design of large specialized container terminal based on the analysis of the detail design of the storage yard, gate, external roads and elevation, which provides a reference for the intensive use of land with minimal land cost to meet the needs of the port development.

Abstract:There are always noticeable problems in the port low-voltage distribution design. For example, instantaneous protection of the incoming circuit-breaker for the transformer can’t meet protection selective requirements, cable sections of L.V switchgears are too small, distribution circuits violate the mandatory provisions,error selections of residual current operated protective devices, and etc. Taking engineering projects as study cases,this paper analyzes the reasons for the design errors, and puts forward train of thought and countermeasures, serving as a reference for port electrical designers.

Abstract:Based on the diversity and randomness of arriving vessels, a navigation operation system simulation model of coastal bulk cargo port area is establishe d to analyze the impact of vessel combination pattern on waterway capacity. The simulation result shows that vessel combination pattern has significant effect on waterway capacity. The weighted mean of arriving vessels DWT is defined as characteristic DWT in this paper. There is an exponential relationship between waterway capacity and characteristic DWT; and the longer the navigation duration, the higher the sensitivity of waterway capacity to vessel combination pattern.

Abstract:Based on the analysis of the fluvial process and characteristics of the shallow area of Quangang waterway in the Ganjiang river, this paper carries out a model experiment for determining the waterway regulation scheme for the lower shallower area Quangang. After implementation of the engineering during 2005—2007, the shallow area disappeared and the waterway condition was improved obviously: The waterway not only reaches the present maintenance dimensions, but also satisfies the construction standard stipulated in the development planning of the waterway.

Abstract:The hydrological and sediment conditions are complex and morphology is highly varied in the Yangtze estuary. The temporal and spatial distribution of siltation is also complex in the deepwater navigation channel of the Yangtze estuary. The shallow spots can inevitably take place at the edge of the navigation channel.This paper analyzes the distribution characteristics of shallow spots at the edge of the navigation channel during the periods of 10.0 m-water-depth maintenance and 12.5 m-water-depth trial navigation, as well as the factors that influence the occurrence of shallow spots. The quality control standard of shallow spots at the edge of the deepwater navigation channel in the Yangtze estuary is proposed and adopted, which has obtained favorable application effect.

Abstract:Based on the study of Wanquan river navigation channel first phase construction, we established the orthogonal curve 2D current mathematical model for the reach from Jiaji to Bo’ao in Wanquan river. Firstly, the model was verified with the nature current materials, and the calculated result was consistent with the nature data by adjusting some parameters. Using results of simulation the spring tide and neap tide in dry season as well as spring tide flood season, we analyzed the variation characteristics of underwater topography, water level and gradient ratio along the river reach. The variations of the tidal limit and tidal current limit were displayed. The specific location of tidal reach was given. Finally, 2D plane flow field about Bo’ao reach was analyzed. The results provides a technical support for the navigation channel construction of Wanquan river.

Abstract:The navigation structure of the Changzhou hydro-junction adopts a four-paralleling-lane type,and the flow conditions in the approach channels are quite complicated due to its arrangement and the lock filling & emptying courses. By physical model tests and numerical computations, we study the influence of lock emptying under different downstream water levels on the flow conditions in the downstream approach channels. Considering the lock features, we propose the currently most convenient and effective non-structural measure, i.e. to optimize the locks’ operation modes so as to solve the hydraulic problems. Finally, we determine the suggested controlling downstream water levels and their relating lock operation modes based on the study, which can be used for the lock design and management.

Abstract:Based on the analysis of the bed ev olution and navigation-obstructing characteristics of Wuxue waterway in the midstream of the Changjiang River, we determine the new regulation idea for the waterway which is coordinated with the sand winning plan of the locality and solve the contradiction between the regulation engineering and san winning based on the river model experiment. Meanwhile, we adjust timely the scheme and staged implementation of engineering based on the principle of dynamic management and according to the topographic variation of the engineering site during construction. After the implementation of the project during 2006 and 2008,the waterway evolution trend was basically the same as the model experiment result, the waterway condition was improved obviously, and the san winning activity was regulated.

Abstract:This paper adopts physical model to verify the situ observation data of ship waves of Zhenjiang segment in Sunan canal. The relationship of the maximum ship waves’ height nearby the vertical bank protection and the ship’s speed is also discussed in some different situations. These situations include the different loads and navigation lines of 500 and 1 000 ton ships. The data and conclusion may serve as a reference for the design of bank protection.

Abstract:Guniusha waterway, which is located in the middle Yangtze River, is composed of the restrictive bend and straight segments which are under the control of the double nodes, and has always been maintaining favorable channel conditions. However, in recent years the waterway condition turns adverse and navigation obstruction occurs constantly. Based on the real-measured water and sediment data of Guniusha waterway, this paper analyzes the river bed evolution and navigation obstruction characteristics, reveals the factors which impact the evolution, and proposes corresponding regulation measures, which provides a reference for the engineering practice.

Abstract:The navigable channel selection is the key of channel regulation, because it determines the waterway regulation project layout, which is crucial to the success of the project. The navigable channel selection is more complicated than channel line selection of single-channel reach. On the basis of the alluvial process analysis and the characteristics of navigation-obstruction of Daijiazhou reach in the middle Yangtze River, the shortcoming and merit of two channels of braided reach are investigated respectively. The selection of navigable channel is discussed.The navigable channel is proposed.

Abstract:In order to improve China’s river navigation information services level, a new concept of internet of ships is presented. The main task includes primarily research the construction of internet of ships, and development consideration of each platform on the basis of analyzing the foreign advanced experiences and studying the domestic status and the current problems of river navigation information management and services. In addition, the construction principle is discussed.

Abstract:For the purpose of developing the navigation mark data update system of CENC, based on CENC’s management, we develop the navigation mark data update function of the production software, to achieve beacon technical and management personnel edit and CENC buoy data timely update of the target and effectively improve the CENC the timeliness and accuracy of the navigation mark information, so as to provide timely and accurate information of navigation mark for CENC application management, and better play the CENC’s application functions.

Abstract:Revision of starting point of time is needed when three-point method of settlement prediction is employed for staged loading of large-area preloading. Lack of settlement of early stage of construction is often encountered in engineering practices. The application of three-point method of settlement prediction is confined by such factors as whether it is suitable for staged loading or not, revision of zero point of time, situation of lack of settlement of early stage of construction. It is proven that three-point method is suitable for such conditions as staged loading and lack of settlement of early stage of construction. A more reasonable method of revision of zero point of time which is called equal settlement method is proposed. The result of study of the paper is proven reasonable by an example and project. The instantaneous settlement gotten by use of the present method of revision of zero point of time is usually error.

Abstract:Using self-developed half mould direct shear apparatus, this paper carries out the direct shear test between soil and steel or stone. Different vertical load varies from 50kPa to 200 kPa. Through numerical simulation of shear test of soil and structure under different conditions of stress via PFC2D, this paper studies the shear stress variation and deformation of soil at the interface with the structure. It is concluded that strain softening occurs to soil in the process of shear and the shear stress of soil which rises as vertical stress grows. Shear zone of some thickness appears at the interface when soil and structure interact with each other, which means that the interaction zone covers not only the contact surface but also the soil off the surface to some extent, the range of action in soil extents 5 times’ particle size away from the interface. The surface roughness of structure imposes slight effects upon the change of shear stress.

Abstract:Based on an artificial island project, this paper calculates the settlement of layered clay foundation during construction and after work by classical soil mechanics theory and finite element method separately. The results provide a basis for the determination of the technical scheme. The analysis results show that equivalent layer method gives pretty realistic results of the degree of consolidation for layered clay.

Abstract:Based on the foundation treatment construction of Tangshan Caofeidian coal terminal construction project, this paper expounds the construction technology and consolidation effect of dynamic compaction method,HDVM method, preloading drainage consolidation method + HDVM, HDVM replacement method, etc., and carries out a comparison among them. The results showed that according to different geological conditions and soil distributions under the filling ground, and using different foundation treatment methods, we can improve the foundation bearing capacity significantly and thus meet the needs of the site construction, and provide a reference for the construction of similar projects.

Abstract:Both sides’supporting structures of Shajing pumping station foundation pit include bored piles and three rows prestressed anchorage cables. The size of the foundation pit is 220 m long and 68 m wide. The average excavation depth of the foundation pit is 11 m, so it’s a large deep foundation pit. The pit is on the soft base, and underground water level is 1.2～2.5 m. This paper mainly introduces the hole formation method of the prestressed anchorage cable in the large deep foundation pit with a high water level, analyzes the issues of water and sand gushing, and proposes the methods including improvement of the construction platform’s level and the position and increment of slurry’s density to solve the problem of water and sand gushing. The methods have been verified by actual construction to be effective and feasible.

Abstract:According to the case that mass concrete of the main pier pile caps of Jiashao bridge is easy to crack in construction, because of the enormous section size, slow heat dissipation, easily inducing high inner-outer temperature difference, strong constraint of bottom concrete and piles, and it is difficult to repair the cracks on the pile are, because that the pile caps are all underwater, we design the standard of temperature controlling on the basis of simulated result of temperature and thermal stresses distribution of mass concrete. By taking some temperature control measures, such as controlling pouring temperature of concrete, applying recycling cool water, insulated and humidity curing, and controlling the quality of concrete, harmful cracks don’t appear in the main pier pile caps of Jiashao bridge and anticipated controlling effect is achieved.

Abstract:In the design of sheet pile wharf, in order to reduce the earth pressure on the sheet pile, we commonly design a row of blind piles at a certain distance behind the sheet pile, including precast concrete pile,steel pipe pile and cast-in-situ pile， among which，the cast-in-situ pile is the most commonly used one. The calculation result proves that the rectangular cross-section is better that the circular one, but the construction of the rectangular cross-sectioned pile commonly uses the conventional equipment, which is characterized by low pore-forming efficiency and is difficult to ensure the construction quality. The air lifted reverse circulation multi-drilling technology and equipment presented in this paper are applied to the construction and have achieved satisfactory effects.

Abstract:The manufacture, launching and placing of ultra-large perforated caissons are great challenges for the construction equipment and technique. Taking caissons of berth No.4 on the north pier of Dongjiakou area Qingdao port as an example, this paper presents the perforation plugging technique of suspended steel formwork, which recovers the shortage of conventional plugging methods. With this new technique, perforations on the midfeathers could be left unplugged and caissons can be placed at high tide. Moreover, the paper introduces the calculation and key construction technique in the launching and placing process of perforated caissons. The successful practice of the project provides a reference for the launching and placing process of ultra-large perforated caissons.

Abstract:Taking the 300 000 ton-class oil terminal engineering of catfish bay in Dalian Port as an example, this paper analyzes the solution for the problem that the largest depth of semi-submersible barge could not meet the request of floating stability of large-scale caisson. A comparison with the method of 300 000 ton-class oil terminal engineering in Yingkou port is made. The result shows that the technology of semi-submersible barge shipping large-scale caisson assisted by crane ship is feasible. This method is an improvement of the original shipping technology for the large-scale caisson and had broadened the appliance field of the semi-submersible barge shipping large-scale caisson.

Abstract:Bonded rebars technique is widely applied to civil engineering, but rarely applied to marine harbor engineering. In order to study the application of bonded rebars in marine harbor engineering, this article analyzes the failure mode of bonded rebars in plain concrete structure based on the theory of post-install fastenings, which was successfully applied to the repair of a wharf’s breast wall.

Abstract:The traditional way of beach protection separates water from surrounding soil and biological environment, and thus destroys the unintended consequences of natural river, which leads to serious environmental problems. Based on Anqing waterway regulation project, this paper introduces a highly efficient ecological beach protecting structure, reinforced three-dimensional mat, which overcomes the shortcomings of traditional structures which are characterized by easy aging and poor integrity.