Abstract:This paper focuses on the new developments in the rainfall-runoff model of the hydro-informatic modeling system(HIMS). The original rainfall-runoff model of HIMS is the LCM model, which is based on the dynamic rainfall infiltration mechanism and has been built through a large number of field observation experiments in small watersheds. In order to further understand the physical mechanism of the LCM model, the HIMS research team proposes a new GAF model based on the Green-Ampt model whose physical mechanism is clear. Theoretically, the LCM model and the SCS-CN model can be directly derived from the GAF model, it is proven that the LCM model is a high-accuracy power exponent approximation of the GAF model, and that the SCS-CN model is a simplification of the reciprocal linear approximation solution of the GAF model. Based on deep analysis of the analytical solution of the GAF model, a modified SCS-CN method with two new parameters, which considers the impact of rainfall intensity, is proposed.

Abstract:Water resources constraints constitute a significant bottleneck in China. The origins of water are worth further research, as they relate to the Earth’s formation, the origins of the water globe, and the issue of deep water. First, we attempt to divide the hydrosphere into several belts and focus on the complex interaction between spherical layers. Then, water resources development issues are discussed, the concept of the comprehensive effect and related evaluation of the evolution of an entire basin is developed based on the spherical layer movement, and the evolution of the middle reaches of the Yellow River, the middle and upper reaches of the Yangtze River, and the inland river basin is analyzed based on this concept. Water resources development should consider three properties: limits, relativity, and ecology, as well as the instructive observation that water can carry a boat and also overturn a boat. The comprehensive development and utilization of water from six different sources, including rainwater, river water, lake water, groundwater, reservoir water, and sea water, are examined. We also discuss prevention and mitigation of six types of disasters related to the six water sources: flooding, waterlogging, drought, storm surges, geological disasters, and water pollution. It is pointed out that segmented control of water quality in the reservoir area, comprehensive development of surface water and groundwater, and construction of underground reservoirs are important. Finally, some suggestions for water resources development and disaster prevention are proposed: cooperation between multiple departments and multiple disciplines, implementation of water-saving measures, construction of an enhanced water resources network, determination of demand according to provision, and improvement of an investigation system for evaluation and development.

Abstract:In accordance with demands of the National Program for Medium- and Long-term Scientific and Technological Development for cutting-edge research on hydro-structure engineering, and in consideration of the characteristics of high dams, super high dams, and dangerous dams, significant scientific and technological problems in hydro-structure engineering are examined. Representative achievements and progress in research on stress, ultimate bearing capacity, and nonlinearity analysis are reviewed, and then the advantages and disadvantages of current theories and methodologies are analyzed. Finally, development directions, including the macro-meso-nano coupling analysis model, micro-nano scale analysis method, stochastic fatigue theory, and the comprehensive analysis theory and method for health diagnosis based on stress, ultimate bearing capacity, and nonlinearity analyses in hydro-structure engineering, are proposed.

Abstract:A systematic review was conducted of isotope hydrology, focusing on the relationship between precipitation and runoff, soil moisture movement in the unsaturated zone, and source identification and age determination of groundwater, as well as paleoflooding. It was found that isotope hydrology can describe the microscopic processes of water transformation during runoff formation and watershed flow concentration. The current research progress of isotope hydrology at Hohai University is summarized, including isotope hydrology mathematical models, experiments on partitioning of isotope runoff components in plain areas, application of isotopes in groundwater, water quantity distribution during the water diversion from the Yangtze River to Taihu Lake, and tracking of nitrogen sources in a watershed. Based on the review, present limitations of research on isotope hydrology are analyzed, and prospective future directions of research on application of isotope techniques in hydrology are described.

Abstract:This paper reviews the research achievements from Hohai University in mechanics of flow and sediment transport in plain rivers and river treatment practices, including vegetated river flow, flow and sediment transport over rippled beds, hyporheic exchange, river confluences, erosion prevention around piers, sediment deposition prevention downstream of sluices, simulations of flow and sediment transport in complex river networks, and techniques for multi-objective hydraulic control. This paper describes the application of these methods to the solution of many practical problems related to flood and waterlogging control, waterway improvement, and water environment treatment of large- and medium-scale complex river networks in the Yangtze River, Huaihe River, and Pearl River basins. Important issues needed to be concerned in plain river treatment in China are pointed out.

Abstract:Coastal tidal flats are important land reserves, as they have significant potential for enlarging living space. Based on the characteristics of coastal tidal flats in Jiangsu Province, the guidelines, overall layout, and principles of large-scale development and utilization of tidal flats are discussed. It has been found that large-scale rapid reclamation and other human activities have large impacts on the offshore environment. The impacts of large-scale development and utilization of tidal flats on offshore dynamic conditions and the ecological environment are discussed, and corresponding environmental protection measures are provided.

Abstract:The characteristics and development of cement sand and gravel(CSG)dams are reviewed, and several typical CSG dams around the world are described. Then, engineering properties of CSG material are described in detail, with a discussion of laboratory testing features, the constitutive model, and durability of CSG material. The workability of CSG dams is examined through static and dynamic structural analysis, temperature stress analysis, and stability analysis. Model tests, cross-sectional design, and construction technology of CSG dams are described. Some shortcomings of previous research are pointed out. Finally, some new directions for research on CSG dams and CSG material are suggested.

Abstract:Recent progresses in research on the regularity and mechanism of sea level variations and their impacts on the offshore and coastal environment in China from 2006 to 2015 are reviewed systematically. The regularities of global and regional sea level variations and steric sea level variations on different time scales were studied, and the mechanisms of sea level variations are discussed, including the dynamic and thermodynamic effects on sea level variations in different seas due to the sea surface heat flux, freshwater flux, circulation, wind stress, and Rossby waves. The sea level variations over the 21st century were also modeled using statistical methods and numerical simulation methods. It is concluded that sea level variations have influenced ocean dynamic processes such as tidal wave changes, and further influenced the offshore and coastal environment through coastal erosion, seawater intrusion, soil salinization, estuarine saltwater intrusion, submergence of coastal lowlands, and decline of mangroves.

Abstract:Marine energy utilization engineering is one of main issues in the field of harbor, coastal, and offshore engineering. This paper reviews recent advances in investigation and evaluation of energy resources, energy conversion technology, and demonstration projects. Key scientific and technical problems for innovative structures, the safety and stability of structures and foundations, the impact on sea water and sediment environment, the conversion rate, and the grid connection technique, which need to be further studied and practiced, were study emphases as they remain difficulties in large-scale utilization of marine energy.

Abstract:Three methods currently used in earth slope stability analysis, including the limit equilibrium method, limit analysis method, and numerical analysis method, are reviewed in this paper. Analyses show that(a)the traditional limit equilibrium and limit analysis methods were developed rapidly in the 20th century; (b)with the development of computer techniques and numerical methods in the 21st century, three-dimensional(3D)numerical analysis methods(e. g. , the finite element method and finite difference method)have been developed and widely accepted because of their significant advantages; and(c)although these 3D slope stability analysis methods have been improved, there are still some problems. Based on analysis of the existing problems and development trends of the 3D slope stability analysis methods, some ideas are presented for the future development of these analysis methods.

Abstract:The purpose and significance of blasting-induced vibration prediction are introduced, and the development courses of the prediction methods and their advantages and disadvantages, including the statistical analysis method, dynamic analysis method, and numerical simulation method based on field measurements and the hybrid vibration course prediction method, are reviewed in detail. Based on the authors achievements, two advanced prediction methods, the improved Anderson model and the nonlinear functional series model, are introduced. Moreover, the basic principles and applicable conditions of the mode-superposition response spectrum method, the transfer function method, and the time-history analysis method, as well as their predictions of structural vibrations, are summarized. Finally, the development trend of prediction of blasting-induced vibrations is described.

Abstract:Some progresses in the research of micro-regimes of seepage around the dam site of hydropower stations under operational conditions are reviewed, with a focus on the groundwater quality, the formation and evolution of seepage precipitates as well as the factors influencing them, and geochemical simulation of water-rock interaction. On the basis of discussion of related problems, four topics are presented for further research, including the chemical damage caused by abnormal variation of groundwater quality, geochemical behaviors of some trace elements from seepage precipitates and their denotative meanings, multi-scale models for multicomponent reaction-transport between liquid and solid phases and their application in consideration of chemical reaction-induced variation in mesostructures, and the uncertainty and methodology involved in geochemical simulation of water-rock interaction.

Abstract:Through a review of recent investigations into the effects of hydrodynamic action on the adsorption/release of pollutants(heavy metals, phosphorus, etc. )by sediments, the influence of water turbulence intensity and velocity on the distribution of pollutants in water and sediment in rivers was analyzed. The results show that, when the turbulence intensity is low, sediments occur in a form close to bed sediment, and the rate and extent of adsorption/release of pollutants by sediments are low. As the turbulence intensity increases, the shear stress at the water-sediment interface increases, sediment suspension is promoted, and the contact area between pollutants and suspended sediment particles increases, leading to a significant increase in the rate and extent of adsorption/release of pollutants by sediments. The effect of the water velocity on the distribution of pollutants in water and sediment is complex. When the sediment is stationary, with the increase of the velocity, the boundary layer thickness decreases, the dissolved oxygen content in water and redox potential increase, the diffusion of pollutants in the water body changes from molecular diffusion to turbulent diffusion, and the pollutant exchange flux at the water-sediment interface increases. With further increase of the velocity, the bed sediment gradually moves and is suspended. At this moment, the state of sediment movement, intensity of collision between suspended matters, and flocculation of sediments also have effects on the adsorption/release of pollutants by sediments. Because of the extensive factors and the complexity of the functional mechanism, there is a disagreement between results regarding the influence of sediment movement on the adsorption/release of pollutants by sediments reported by different researchers, and simplification is carried out through mechanism studies and establishment of mathematical models. It is pointed out that future studies should focus on the mechanism of the influence of the water and sediment movement as well as chemical and biological processes on the distribution of pollutants in water and sediment in rivers and the interaction of oxygen consumption organics and nocuous organics with sediments.

Abstract:In order to improve the durability of mortar, the method of electro-migration reaction of silicate ion was used to treat mortar. Through comparison tests, the durabilities of different mortar specimens, including a control mortar specimen, a treated mortar specimen without surface coating, and a treated mortar specimen with surface coating, in resisting carbonization, sulfate attack, chloride diffusion, and corrosion of rebar by chloride ions were investigated. The microcosmic mechanism of the effects of this method on the durabilities of mortar was analyzed using a scanning electron microscope (SEM) and a mercury intrusion porosimeter (MIP). The results indicate that the durabilities of the mortar specimens in resisting carbonization, sulfate attack, chloride diffusion, and corrosion of rebar by chloride ions can be sequenced from low to high in the following order: control specimen, treated specimen without coating, and treated specimen with coating. The effect of the method of electro-migration reaction of silicate ion in improving the durability is due to its contribution in production of surface coating and mortar densification. Compared with densification of mortar, the produced coating has a relatively smaller effect on the improvement of durability due to its low thickness and numerous micron-grade pores.

Abstract:This paper introduces the background, aims, and content of the journal Hohai Monthly, which was launched by the first hydraulic college in China, Hohai Civil Engineering School(now Hohai University), in November 1917. The journals historical status in the scientific and academic community and social influence are examined. The study shows that the journal is the longest-running hydraulic scientific and technical periodical in China. Development of an excellent group of authors has been the greatest contribution of Hohai Monthly to Chinese social development. Some articles published in previous decades of the journal still have academic value. Hohai Monthly inherited and carries forward a concept of serving the national interest through scientific inquiry and industrial development, as well as the goals of scientific rigor, realism, exploration, and innovation.