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Morphodynamic Characteristics and Medium-Term Simulation of the North-South Passage Under the Impact of the Yangtze Estuary Deepwater Navigation Channel Project

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China Ocean Engineering 2020年第2期34卷 198-209页

作者： JIAO Jian dou xi-ping GAO xiang-yu DING Lei YANG xiao-yu Key Laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing Hydraulic Research InstituteNanjing 210029China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China

The morphological evolution characteristics of the North-South Passage area since the construction of the Yangtze Estuary Deepwater Navigation Channel Project(DNCP)are analyzed on the basis of the measured data.A twodimensional morphodynamics numerical model of the Yangtze Estuary is established to verify the morphological evolution of the North-South Passage under the influence of the DNCP and to predict the future evolution in the next 40 *** analysis shows that the North Passage has experienced rapid adjustment stages and adaptive stages after the construction of the *** erosion occurred along the main channel,and slow siltation could be observed in the area between the *** South Passage showed a state of upper section erosion and down section *** present,the whole South Passage is in a slight erosion *** to the numerical model,the eroding and silting speed of the North Passage will slow down in the *** present state that erosion occurs in the main channel and siltation occurs between the groins will *** South Passage will still maintain upper section erosion and down section deposition in the *** to the main channel erosion of the North Passage and siltation of the South Passage,the sediment division ratio of the North Passage will increase in the future but still be smaller than 50%.After morphological evolution of 40 years,the direction of residual sediment transport caused by M2 and M4 tidal components in the North Passage has not changed,but the transport rate will *** is considered that the morphological evolution of the North-South Passage could reach a relatively stable state after 40 years.

关键词： Yangtze Estuary numerical model morphology tidal current sediment transport deepwater navigation channel project(DNCP)

Influence of Spur Dike on Hydrodynamic Exchange Between Channel and Shoal of Generalization Estuary in Physical Model Test

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China Ocean Engineering 2017年第5期31卷 624-630页

作者： JIAO Zeng-xiang dou xi-ping ZHENG Jin-hai ZHANG xin-zhou GAO xiang-yu Nanjing Hydraulic Research Institute College of Harbor Coastal and Offshore EngineeringHohai University Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of Transport

Widely applied in maintaining estuarial waterway depth, the spur dike has played an important role in currents and sediment exchange between channel and shoal and sediment back-silting in the channel. Through establishing a generalized physical model at a bifurcated estuary and conducting current tests under the joint action of runoff and tide, the influence of the spur dike length on current exchange between channel and shoal is analyzed. Results show that when the spur dike length reaches a certain value, the direction of the flow velocity shear front between the channel and shoal will change. The longer the spur dike, the larger the transverse fluctuating velocity at the peak of flood in the channel shoal exchange area, while the transport of the transverse hydrodynamics is obvious in the process of flood. There is an optimum length of spur dike when the shear stress in the channel and the longitudinal velocity in flood and ebb reach the maximum, and the flow velocity will decrease when the spur dike length is smaller or larger than the optimum. For a certain length of spur dike, the larger the channel shoal elevation difference, the larger the peak longitudinal flow velocity in the middle of the navigation channel in flood and ebb. However, the transverse flow velocity will first decrease and then increase. The transverse transportation is obvious when the channel shoal elevation difference increases.

关键词： spur dike hydrodynamics flow velocity channel shoal exchange physical model

Study on Volume Variation and Stability of Riverbed in the Yangtze Estuary

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China Ocean Engineering 2023年第3期37卷 433-446页

作者： DING Lei JIAO Jian TONG Chao-feng WANG Yi-fei CHEN Ben SUN Jie-ying dou xi-ping Key Laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing Hydraulic Research InstituteNanjing 210029China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu 610065China

In recent years,regional floods and typhoons have occurred in the Yangtze *** dynamic conditions and dramatic reduction of sediment discharge in the basin are affecting the dynamic equilibrium pattern of the Yangtze *** on the field measurement data and theoretical derivation,this paper analyzed the changing process of runoff-sediment discharge into the sea after the operation of the Three Gorges Project(TGP),and the tidal dynamics and sediment variation characteristics of the Yangtze *** erosion of South Branch mainly occurs in the channel below-10 m contour,and the riverbed volume below contours 0 m and-10 m has a good correlation with the sediment discharge of Datong Station in the previous *** this basis,the ratio of the horizontal distance from the starting point to the section centroid below the average water level(B_c)and the water depth at the section centroid(H_c)was proposed to describe the change of the section *** relationships between the water-diverting ratio,the sediment-diverting ratio and the water-diverting angle,the conditions of runoff and sediment discharge from the upper reach and the characteristics of the riverway section were established,and the theoretical calculation equations of the water-diverting ratio,the sediment-diverting ratio and the diverting angle of each bifurcation were also established.

关键词： Yangtze Estuary volume variation section shape riverbed stability

Mechanism of the Impact of Floods and Typhoons on the Morphological Evolution of the Yangtze Estuary

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China Ocean Engineering 2023年第3期37卷 447-457页

作者： JIAO Jian DING Lei HAN Yu-fang SUN Jie-ying YANG xiao-yu HUANG Yu-ming dou xi-ping Key Laboratory of Port Waterway and Sedimentation Engineering of MOTNanjing Hydraulic Research InstituteNanjing 210029China State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China

In the last two decades,the Yangtze Estuary has undergone significant changes under the influence of reduced sediment inflow and estuary *** study investigates the influence of floods and typhoons on sediment concentration and the morphological evolution of shoals and channels in the Yangtze *** analysis is conducted through the utilization of topographic data measured pre-and post-flood events and observations of hydro-sedimentary changes during *** using a generalized estuary mathematical model,this study examines the interplay between varying tidal ranges,tidal divisions,runoff volumes,and regulation projects on the erosion and deposition of shoals and channels in bifurcated *** results show that due to the implementation of river and waterway regulation projects,the impact of the 2020 flood on the main channel and shoal was significantly less than that of the1998 *** swing amplitude of the South Branch main channel ***,local river sections such as the Southern Waterway of Baimao Shoal exhibited *** typhoons,sediment concentration in the 20 cm above the bottom increased significantly and was closely related to wave processes,with a weakened correlation to tidal *** typhoons,high shoals in South Passage above 0 m were silted up,while the terrain on one side of the tail of Jiuduan Shoal in the downstream deep-water area was generally scoured due to strong wave *** generalized mathematical model of the bifurcated estuary revealed that M2 tidal component contributed most to the ero sion and deposition evolution of estuary shoals and channels,with floods exhibiting characteristics of sedime ntation on shoals and erosion on *** the implementation of a branch rectification project,branch resistance increased,diversion decreased,and the riverbed changed from pre-project erosion to post-project sedimentation,with an increase in erosion in non-project branches.

关键词： the Yangtze Estuary flood typhoon morphological evolution

Development of All-Weather and Real-Time Bottom-Mounted Monitor of Bed Load Quantity

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China Ocean Engineering 2014年第6期28卷 807-814页

作者：窦希萍左其华应强黄海龙 Key Laboratory of Port Waterway and Sedimentation Engineering of Ministry of Transport of the People's Republic of China Nanjing Hydraulic Research Institute

Quantity of bed load is an important physical parameter in sediment transport research. Aiming at the difficulties in the bed load measurement, this paper develops a bottom-mounted monitor to measure the bed load transport rate by adopting the sedimentation pit method and resolving such key problems as weighing and desilting, which can achieve long-time, all-weather and real-time telemeasurement of the bed load transport rate of plain rivers, estuaries and coasts. Both laboratory and field tests show that this monitor is reasonable in design, stable in properties and convenient in measurement, and it can be used to monitor the bed load transport rate in practical projects.

关键词： quantity of bed load bed load rate sediment transport real-time monitoring measuring apparatus

Hydrodynamic Effect of the Regulation Project of Yangtze River Deepwater Channel Downstream of Nanjing

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China Ocean Engineering 2013年第6期27卷 767-779页

作者：杨东利窦希萍张新周罗小峰 College of Harbor Coastal and Offshore Engineering Hohai University President's Office Nanjing Hydraulic Research Institute Key Laboratory of Port Waterway & Sedimentation Engineering MOC Nanjing Hydraulic Research Institute

A two-dimensional flow numerical model of the tidal reaches, which total length is more than 700 km, is established from Datong to the Yangtze River estuary. The tidal levels, velocities, diversion ratios and dynamic axes before and after the separate regulation of each reach and combined regulation of all reaches are obtained. The comparative analysis shows that the regulation project of a separate reach basically has no impact on velocity distributions and variations of diversion ratios of upper and lower reaches, the variations of dynamic axes are only within the local scope of the project. The regulation project of a separate reach also has less impact on the water level in the lower adjacent reaches, but will make the water levels in the upper reaches rise. After the implementation of the regulation projects for all reaches, the rise of water level in the upstream reaches will have a cumulative impact.

关键词： Yangtze River deepwater channel regulation project numerical model

长江口深水航道回淤量预测数学模型的开发及应用

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水运工程 2006年第B12期 159-164页

作者：窦希萍南京水利科学研究院江苏南京210029

通过对长江口径流、潮流和波浪共同作用下的泥沙运动规律的研究,开发并建立了长江口全沙(悬沙和底沙)数学模型。大量实测资料验证表明,该数学模型可以较好地模拟长江口地区的潮位、流速、流向、含沙量、底沙、分流比、南北槽地形变化和... 详细信息

通过对长江口径流、潮流和波浪共同作用下的泥沙运动规律的研究,开发并建立了长江口全沙(悬沙和底沙)数学模型。大量实测资料验证表明,该数学模型可以较好地模拟长江口地区的潮位、流速、流向、含沙量、底沙、分流比、南北槽地形变化和台风暴潮造成的航道骤淤情况。在此基础上采用全沙模型研究了长江口深水航道治理工程一、二、三期工程实施后航道的年回淤量和回淤分布以及发生“二碰头”和“三碰头”时的航道回淤量。一、二期工程建成后的航道实测回淤资料表明,全沙数学模型所预报的航道回淤分布和淤积总量与实测值相当接近。

关键词：长江口航道泥沙回淤数学模型

Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane

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Chinese Journal of Polymer Science 2024年第1期42卷 87-96,I0009页

作者： Yi-Lang Qin ping Zhu Chen-xi Ouyang xia Dong Fuwai Hospital Chinese Academyof Medical Sciences&Peking Union Medical College/National Center for Cardiovascular DiseasesBejing 100037China CASKey Laboratoryof Engineering Plastics CAS Research/Education Centerfor Excellence in Molecular SciencesInstitute ofChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical *** investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol.

关键词： Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties

Experimental investigation of dynamic characteristics of leaching tubing for solution mining of salt cavern carbon and energy storage

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Petroleum Science 2024年第4期21卷 2703-2722页

作者： Yin-ping Li xin-Bo Ge xi-Lin Shi Hong-Ling Ma State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil Mechanics Chinese Academy of Sciences University of Chinese Academy of Sciences College of Energy and Mining Engineering Shandong University of Science and Technology State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology

Salt caverns are extensively utilized for storing various substances such as fossil energy, hydrogen,compressed air, nuclear waste, and industrial solid waste. In China, when the salt cavern is leached through single-well water solution mining with oil as a cushion, engineering challenges arise with the leaching tubing, leading to issues like damage and instability. These problems significantly hinder the progress of cavern construction and the control of cavern shape. The primary cause of this is the flowinduced vibration instability of leaching tubing within a confined space, which results in severe bending or damage to the tubing. This study presents a model experimental investigation on the dynamic characteristics of leaching tubing using a self-developed liquid-solid coupling physical model experiment apparatus. The experiment utilizes a silicone-rubber pipe(SRP) and a polycarbonate pipe(PCP) to examine the effects of various factors on the dynamic stability of cantilevered pipes conveying fluid. These factors include external space constraint, flexural rigidity, medium outside the pipe, overhanging length, and end conditions. The experiments reveal four dynamic response phenomena: water hammer, static buckling, chaotic motion, and flutter instability. The study further demonstrates that the length of the external space constraint has a direct impact on the flutter critical flow velocity of the cantilevered pipe conveying fluid. Additionally, the flutter critical flow velocity is influenced by the end conditions and different external media.

关键词： Salt cavern storage Solution mining Leaching tubing Experimental investigation Flutter instability