Abstract:Jiyun River,as an important estuary channel of the Haihe River system,not only conveys upstream floods but also bears drainage responsibilities along both banks.During the rainy season,when the southeastern flow of the Chaobai River intersects with the downstream river water and seawater of Jiyun River under tidal conditions,obstructions occur,forming rapid currents and vortices.The river is meandering with gentle slopes,leading to frequent flood and waterlogging disasters on the Jiyun River Plain.Based on measured data,the hydrological characteristics of floodwater,waterlogging,and tidal interactions in Jiyun River are analyzed,and six characteristic years—1962,1994,1959,1967,1969,and 1984—are selected to represent the occurrence patterns and combination modes of floodwater and waterlogging events.The modern hydrological monitoring and forecasting concept of the"three lines of defense",the collaborative operation strategy of engineering systems,and the theory of resilient flood control are systematically introduced into the management practice of Jiyun River.A multi-dimensional solution is proposed,encompassing integrated space-sky-ground monitoring,forecasting,and early warning,joint regulation of reservoirs,sluices,and flood detention areas,systematic river channel management,and digital technology empowerment,promoting the transformation of the flood control and drainage system of Jiyun River from traditional engineering defense to a resilient system with forecasting and early warning,precise operation,and rapid recovery capabilities.

Abstract:Flash flood disasters are characterized by strong suddenness and high destructive power,posing serious threats to the lives and property of residents in Wuan City and affecting regional sustainable development.To understand and grasp the flood evolution patterns in small watersheds within Wuan City and provide scientific data support for flash flood disaster prevention,this paper conducted a historical flood investigation in the small watershed of Mahui River as an example.Methods including community interviews,flood mark surveys,cross-section measurements,and hydrological calculations were employed.The analysis determined that the flood peak of Mahui River in 2021 was 466 m³/s,with a return period of 30 years.The investigation and analysis results provide technical support for risk assessment,optimization of early warning and forecasting systems,and non-structural mitigation measures for flash flood disasters in small watersheds of Wu'an City,and have significant practical implications for enhancing regional flash flood disaster defense capacity.

Abstract:In recent years,extreme weather events such as heavy rainfall have occurred frequently,causing slope instability in hilly areas,which seriously affects the safe operation of engineering projects.Exploring scientific and effective geological investigation methods for slopes and revealing the evolution mechanism of landslides is of significant importance.Taking the slope at Tangou Landfill in Anyang as the research object,this paper combines microtremor exploration with traditional investigation methods.By integrating and interpreting multi-source survey results,differences between the landslide body and undisturbed soil in terms of strength and wave velocity are identified,the slip surface location is determined,and the range and boundary of the landslide body are clearly delineated.On this basis,the causes of landslide formation and its evolution mechanism are analyzed,and corresponding prevention,control,and monitoring suggestions are proposed.The research results can provide a reference for geological investigation and slope management in similar projects.

Abstract:Water security is an important component of national security,relating to resource security,ecological security,economic security,and social security.Evaluating Beijing's water security in the new era,summarizing existing problems,and proposing countermeasures is of significant guidance for improving the city's water security assurance.This paper establishes a comprehensive water security assessment indicator system for Beijing based on the"natural-social"dual water cycle,and uses a model of water security degree calculation combining single-indicator quantification,multi-indicator synthesis,and multi-criteria aggregation to evaluate Beijing's water security from 2012 to 2022.The results indicate that the water security index of Beijing steadily increased during 2012-2022,with the water security situation improving year by year.The water security degree improved from a basically safe level in 2012 to a relatively safe level in 2016,and further reached a safe level in 2021.Based on the assessment results and projections for future water security,this paper proposes countermeasures for water security in Beijing,aiming to provide reference and guidance for research on the city's water security assurance.

Abstract:In order to continuously improve Beijing's flood control system,it is necessary to conduct an in-depth analysis of the rainfall and water conditions in the city's small-and medium-sized rivers.Taking Xitucheng Ditch in the north canal river system as an example,precipitation data for the region in 2024 were collected and compiled.Focusing on elements such as rainfall,river water conditions,and diverted water supply,and combined with historical data for comparative analysis,it was concluded that during the 2024 flood season,small-and medium-sized rivers in Beijing were characterized by abundant precipitation and ample diverted water supply,with rainfall unevenly distributed throughout the year.The results of this study provide strong data support for flood control decision-making in small-and medium-sized rivers.

Abstract:Water resources are a fundamental constraint for sustainable social development.This paper takes the Green Circular Economy Industrial Park in the Beijing Sub-Center as the research object.Considering the park's location in the restricted groundwater exploitation area of Yongledian Town,Tongzhou District,where current water supply fully relies on Quaternary groundwater and the annual water withdrawal is limited by a 23.26 million m³"red line",the study adopts a"dual control of supply and demand"analytical method.Based on the industrial types planned for the park,water demand is calculated,and the water resources conditions of Yongledian Town are systematically analyzed using hydrogeological survey data.The results indicate that,from the perspective of water quantity,the Quaternary groundwater in Yongledian Town is currently not over-extracted,and the water resources can meet both the town's current demand and the water requirements of three planned projects in the industrial park.However,from the perspective of water quality,the shallow groundwater in the area is mainly Class IV with poor quality.The water level of the deep groundwater,currently the main water source,declined by approximately 4.16 m from 2015 to 2022,and although it rebounded about 0.82 m in 2023-2024,the area still faces a significant risk of"water shortage due to poor water quality".The study shows that the industrial park's planning is generally compatible with regional water resources in terms of quantity,but water quality safety has become a critical bottleneck restricting its sustainable development.The research results provide quantitative support for implementing the principles of"urban planning based on water,land allocation based on water,population planning based on water,and industrial development based on water",and offer a reference for optimizing industrial layouts in groundwater over-exploitation areas in the Beijing-Tianjin-Hebei region.

Abstract:The lower reservoir of the Dianbai Pumped Storage Power Station in Guangdong adopts a concrete gravity dam.From the perspective of economic efficiency and construction convenience,the optimal choice is to use excavated materials from the underground chambers as concrete aggregates.Therefore,it is necessary to study the alkali reactivity characteristics of the excavated materials in the lower reservoir chambers to determine the alkali reactivity properties of the aggregates.For aggregates with potential alkali reactivity hazards,experimental studies are also required to identify effective mitigation measures,providing scientifically accurate experimental data to support subsequent design,construction,and aggregate selection.

Abstract:Research on initial water allocation schemes in river basins has rarely addressed their effectiveness,which restricts the advancement of initial water allocation work in river basins and intensifies public concern regarding the effectiveness of allocation schemes.To assess the effectiveness of initial water allocation schemes in river basins,this paper proposes criteria for effectiveness assessment based on the current water use of the riparian provinces(regions)and the actual demand for reserved emergency water.An effectiveness assessment model for initial water allocation schemes in inter-provincial river basins is then constructed,and an application study is conducted using the Daling River Basin as an example.The results show that the initial water allocation scheme in the Daling River Basin exhibits relatively good effectiveness.On this basis,combined with the assessment results,countermeasures and suggestions for improving initial water allocation schemes in river basins are proposed.

Abstract:The hydropower station project in Pakistan is a long tunnel diversion-type hydropower project with complex geological conditions and high construction difficulty.When tunnel construction encounters adverse geological units such as large lithological boundaries,major faults,fracture zones,densely jointed zones,weak rock masses,areas prone to rockburst,or sections susceptible to water inrush and sudden water inflow as discovered or inferred by preliminary surveys,advance geological prediction,as an important technical measure for tunnel construction safety and schedule management,plays an irreplaceable role.Among them,the integrated method of ground-penetrating radar and infrared water detection is not only efficient but also effective,which can effectively prevent blind construction and guide safe and efficient tunnel construction.

Abstract:In 2023-2024,Shandong Province completed a review of province-wide river and lake list,sort out the list of rivers and lakes in the water census list,as well as the list of rivers with a watershed area of less than 50km2 and lakes with a surface area of less than 1km2 that have management tasks.This paper comprehensively summarizes the results of Shandong Province's river and lake review,briefly explains the criteria of Shandong Province's river and lake review,and refines the issues of river source,estuary,stem-branch relationship,and classification of water bodies,and conducts exploratory reflections on the existing problems and deficiencies from the perspectives of data acquisition,experience,and introduction of the standard.

Abstract:The reservoir in the Yellow River Diversion Plain in Binzhou City is an important drinking water source,and the rate of total nitrogen exceeding the standard has remained high for many years.The phosphorus-containing substances in the Yellow River diversion water are rich and absorbed in sediment,and the total phosphorus content in the overlying water of the reservoir is low,which effectively curbed the eutrophication process of the reservoir to some extent.However,in recent years,there have been a large number of regional algae blooms in reservoirs in summer.Through the analogy analysis of similar reservoirs in the province,this paper concludes that there are ecological risks such as accelerated eutrophication,abnormal algae reproduction and unhealthy development of water ecosystem in severe siltation,low water level operation and hot summer,which further affect the water supply quality and should be paid great attention to.

Abstract:Taking the downstream diversion scheme of Raoyang River as an example,based on the calibration of one-dimensional MIKE11 model and the verification of two-dimensional MIKE21FM model,the influence of different diversion channel widths(50 m,100 m,200 m)on the flood level and diversion efficiency of the river channel is analyzed.The results show that the width of the diversion channel is positively correlated with the decrease in water level,but the increase slows down with the increase of width;The 200 m wide diversion channel reduces the water level by 1.05 m for floods that occur with a return period of less than 5 years,and significantly increases the proportion of diversion flow.The research can provide a reference for the design of flood diversion projects in northern plain rivers.

Abstract:From July 28 to August 1,2023,a heavy rainfall process occurred in the entire Haihe River Basin,with a cumulative surface rainfall of 155.3mm and a total rainfall of 49.4 billion cubic meters,exceeding the"August 96"watershed flood of the Haihe River and the strongest rainfall in the Haihe River Basin since 1963.This article takes typical sections of the Dashi River,Juma River,and Yongding River in Beijing that have been severely affected by floods as representatives.Based on preliminary investigations of flood disasters,the problems in river and lake management are analyzed,and suggestions for further strengthening river and lake management are proposed.

Abstract:The concrete construction volume of the Shizhen Reservoir gravity dam is large,the project is of great importance,and the requirements concrete pouring construction are high.In order to ensure the quality of concrete construction,the temperature control measures for concrete pouring construction are analyzed.The numerical simulation method is used analyze the temperature control effect under different cold water pipe arrangement spacing,and the temperature control effect of each scheme is as follows:0.5 m spacing>1 m spacing>2 m spacing>no water,but the 0.5 m spacing causes a large tensile stress on the concrete surface,which may lead cracks on the concrete surface,so it is recommended to use 1 m spacing to arrange the cold water pipe during the construction process.

Abstract:At present,the world is undergoing profound changes unseen in a century,and as the"14th Five-Year Plan"comes to an end and the"15th Five-Year Plan"begins,the final stage of the post-resettlement support policy for reservoir migrants is approaching.During this period,the economic development of reservoir areas and resettlement areas and the implementation of the policy have encountered many difficulties and obstacles,with numerous uncertainties that affect the sustained effectiveness of the post-resettlement support policy.This article mainly introduces the basic situation of the post-resettlement support policy for large and medium-sized reservoir migrants in Zhongning County,Ningxia,summarizes the main experiences and practices in implementing the policy,analyzes and summarizes the problems and shortcomings,and explores new concepts,implements new methods,and provides new ideas in terms of ideology,system,management,and innovation.It aims to provide practical references and innovative ideas for the implementation of policies in migrant areas and promote the high-quality economic development of migrant areas.

Abstract:Concrete honeycombing and pitting,as typical construction defects in hydraulic engineering,directly affect the structural durability and safety.Taking the repair project of the gate pier in Fushui Reservoir as an example,this study systematically investigates the causes of honeycombing and pitting,the repair process,and the collaborative application of array ultrasonic detection technology.Cause analysis reveals that insufficient vibration,concrete segregation,and formwork leakage are primary contributors.A layered repair process of"chiseling-cleaning-patching-curing"combined with high-grade mortar achieves precise repair.Innovatively,array ultrasonic shear wave reflection imaging technology is introduced for three-dimensional non-destructive defect detection and quantitative evaluation.Detection results indicate good compactness of the repaired concrete with no honeycombs or voids.The study proposes a"precision repair-quantitative evaluation"technical system,providing new insights for quality control of hydraulic concrete.It also recommends multi-method verification for critical projects to enhance defect treatment efficiency and reliability.

Abstract:Flash floods are the leading cause of fatal natural disasters in Zhejiang Province,China.Traditional monitoring devices and warning methods have deficiencies both on feedback mechanisms and efficiency of information transmission.Based on the practical needs of flash flood prevention in Zhejiang,this study develops multiple warning approaches,including public alerts,emergency radio broadcasting,and linked warning on upstream-downstream from on-site equipment,building upon the existing multi-stage warning system.Furthermore,a closed-loop management mechanism has been developed through Zhejiang DingTalk platform,telephone calls,and household alarm devices.These integrated warning approaches and management mechanism are design to deliver warning information rapidly and effectively to the affected populations.This study can provide practical suggestions for flash flood disaster prevention on improving warning efficiency and promoting the safety of lives and property.

Abstract:Concrete erosion deterioration under high sulfate environments is relatively severe.This paper explores the effects of different addition methods of polyester fiber(PF),basalt fiber(BF),and U-type expansive agent(UEA)on the sulfate erosion resistance of concrete by designing indoor sulfate immersion-wet-dry cycle tests.The changes in concrete specimen appearance,mass loss,and pore structure parameters are analyzed,and the sulfate erosion resistance characteristics of different specimens under different erosion cycles are evaluated to reveal the deterioration laws under wet-dry cycle conditions.The erosion mechanism of sulfate on crack-resistant concrete is analyzed from both macro and micro perspectives,and the mechanism by which fiber-UEA co-mixing improves the sulfate erosion resistance of concrete is elucidated.The results show that both single fiber addition and co-mixing of fiber with expansive agent can improve the macro and micro performance of concrete under sulfate wet-dry cycle conditions.Concrete under sulfate wet-dry cycle action is mainly subjected to two types of damage:physical erosion and chemical erosion.Co-mixing of fiber and UEA can significantly improve the erosion resistance of concrete,and its sulfate erosion resistance is superior to that of plain concrete and single-fiber concrete.

Abstract:To understand the current status of eutrophication in Shajingzi Reservoir and propose appropriate treatment measures.Through conducting water environment status surveys and sampling analysis,nutrient levels and algal composition were determined,and the degree of eutrophication was evaluated.The results show that the water body of Shajingzi Reservoir is already in a state of severe eutrophication.Further analysis of the applicability of conventional eutrophication treatment technologies to this reservoir reveals that existing conventional treatment measures cannot meet the treatment needs of Shajingzi Reservoir.On this basis,countermeasures and suggestions such as increasing external clean water supply and implementing in-situ chemical dosing emergency treatment for high-algae water bodies are proposed.The research results can provide reference for eutrophication treatment of Shajingzi Reservoir water body.

Abstract:To study the effects of surrounding rock and support structure of diversion tunnels on time-dependent deformation of the cavern,numerical calculations were conducted using finite element analysis software to analyze the time-dependent laws of stress and deformation of surrounding rock under different anchor bolt lengths and moisture content conditions.The results show that surrounding rock displacement increases with time,and long anchor bolts can effectively restrict surrounding rock deformation;the longer the anchor bolt,the smaller the surrounding rock displacement.After 80 d of tunnel support,the surrounding rock displacement under the 5.0 m anchor bolt condition decreased by 36.55%and 64.02%compared to the 3.0 m and 2.0 m anchor bolts,respectively.The normal stress of the surrounding rock gradually increases with time,with faster stress increase in the early stage and slower growth in the later stage.Under the 2.0 m anchor bolt condition,the normal stress at 80 d increased by 63.46%compared to that at 40 d,and increased by 1.40%at 360 d compared to that at 320 d.The normal stress of the surrounding rock decreases with increasing moisture content;at 100 d with a moisture content of 20%,the normal stress decreased by 10.74%and 21.74%compared to moisture contents of 14%and 8%,respectively.