With the rapid development of our country's economy and society,significant changes have oc-curred in the operational environment and flood protection objectives of many existing reservoirs.The engineering standards and classifications determined during the dam construction phase no longer align with current control indicators.They are incompatible with the ongoing urban development and fail to adapt to the evolving needs.As a result,they cannot meet the new requirements posed by urban develop-ment in this new era for ensuring water safety and security.Taking the typical urban reservoir Dongpu Reservoir as an example,its storage capacity indicators,flood control indicators,water supply indi-cators,and accident impact indicators are reviewed according to the specifications.The corresponding engineering grades of the indicators are grade II,grade II,grade I,and grade II,respectively.This paper can serve as a reference for other urban reservoir projects and other improvement demonstrations.
The groundwater shows certain toughness under the regulation and storage of precipitation and artificial mining.In order to quantitatively characterize the toughness of the shallow groundwater system,the evaluation index system for the toughness of the groundwater resource system was estab-lished based on Guoyang county of Anhui province,and used Topsis method to evaluate the toughness of the groundwater system in the study area.The results showed that the toughness of groundwater system in the study area was generally increasing from 2011 to 2020,and the toughness level in 2013 was the weakest,but in 2018 is the strongest.The toughness level is mainly restricted and affected by precip-itation,groundwater exploitation degree and self-regulation of aquifer.It may provide technical sup-port for the scientific development,utilization and management of our groundwater system.
Dry-wet(D-W)cycle is one of the vital factors that contribute to the generation of cracks in cohesive soil.The morphology and depth of cracks are the main factors influencing the stability of embankments.Based on laboratory experiments and theoretical research,this paper explored the mor-phology and depth of cracks in cohesive soil under D-W cycle effects.Furthermore,it investigated and discussed how D-W cycling influences the mechanism of crack formation.The results showed that during the drying process,the matric suction of cohesive soil increased,causing the soil to transition gradually from a saturated state to an unsaturated state.The matric suction of cohesive soil was greatly influenced by the soil moisture content.During the desiccation process,significant tensile stress was generated,and when the moisture content of the unsaturated soil reached a critical value,it led to soil cracking.The study also showed that D-W cycle led to the formation of grid-like cracks in cohesive soil embankments.The depth of the crack zone was deeper at the crest of the embankment and shallower at the bottom.The influence of D-W cycle on the depth of cracks was a dynamic process,primarily influenced by climate change and the depth of groundwater burial.There was an approximate linear relationship between crack depth and groundwater depth in embankments.
To solve issues such as limited construction space,short construction periods,and poor river landscape in the urban riverbank management,using a comprehensive river rehabilitation project in Guangzhou as an example,a construction-friendly,self-embedding,vegetated green ecological barrier wall is proposed.The paper analyzes and calculates its structure,advantages,construction process,and stability.The results indicate that the self-embedding ecological barrier wall has a stable struc-ture and strong foundation adaptability.It can harmonize with the surrounding river landscape while meeting the requirements for flood control and drainage.The application of this approach in compre-hensive river channel management projects has shown positive effects,providing a good reference for similar river channel management initiatives.
At present,there are problems such as insufficient experience,single forms,and overempha-sizing rehearsal while neglecting training in flood control drills in water conservancy construction projects.As a result,the drills may not achieve desired effects or be merely formalities,with sig-nificant gaps from actual needs.To enhance the effectiveness of flood prevention drills in water con-servancy construction projects and raise awareness among all parties involved,we have proposed corre-sponding strategies and suggestions based on the summary of past flood prevention drill experiences.By incorporating instances of accidents during the flood season in ongoing construction projects and research achievements in emergency management,we hope that these suggestions will contribute to the better implementation of flood prevention drills in water conservancy construction projects..
Timely understanding of sedimentation changes in the Shenzhen River,the boundary river be-tween Shenzhen and Hong Kong,is crucial for accumulating relevant foundational data and for the ef-fective operation and management of the river.Relying on the Shenzhen River Topographic measurement project with the aim of acquiring topographic and geomorphic data of the Shenzhen River,and based on the analysis of the shortcomings of traditional surveying methods in tidal river mapping,the project employed cutting-edge technologies such as three-dimensional laser scanning,unmanned boat measure-ment,oblique photogrammetry,etc.,to conduct comprehensive measurements of the Shenzhen River chan-nel.The synergistic application of various cutting-edge surveying techniques had greatly improved op-erational efficiency,effectively ensuring the accuracy of results and the integrity of data acquisi-tion,laying the foundation for subsequent result mapping.The multi-source water depth data acquisi-tion technology could be applied in similar tidal river cases,demonstrating significant benefits.
To provide a basis for proposing measures to cope with regional drought risks and to further promote the research on the zoning of drought prevention and control areas,a quantitative assessment of drought risk and zoning of drought disasters are conducted from the perspective of risk management.The risk assessment is carried out at the county level,with agricultural drought disasters and the difficulty of drinking water due to drought calculated as risk indicators.The risk zoning for agri-cultural drought and the difficulty of drinking water due to drought is conducted using an equal in-terval method.Finally,based on the principle of the worst-case scenario,a comprehensive risk zoning of drought disasters is determined.The results showed that the high-risk areas of agricultural drought disaster in Anhui Province were mainly concentrated in Funan county in the northern area of Huaibei Plain and the Jianghuai Watershed erea Mingguang city,Dingyuan county and Jingde county.The high-risk ereas for drought-related drinking difficulties were located in Yuexi county,Shitai county and Jingde county in the mountainous areas of western Anhui Province and southern Anhui Province.There were no high-risk zones for drought disasters in cities and towns;six county-level administra-tive districts(Funan county,Mingguang city,Dingyuan county,Jingde county,Yakeshi county and Shi-tai county)were at high risk.The drought disaster is synthesized as a high-risk area.The results of risk zoning help to grasp the distribution of drought disaster risk in Anhui Province,and could pro-vide scientific basis and technical support for drought disaster risk management.
In addressing the challenge of determining a comprehensive solution for the decision-making of reservoir control gate types with certain landscape requirements,taking the case of the reservoir control gate at Henghu Modern Agricultural Science and Technology Park as an example,a set of evalua-tion and decision-making criteria was established.This system considers aspects such as river channel flood control,operational maintenance,landscape coordination,sedimentation at the water gate,com-parative investment,and construction requirements.Utilizing a methodology based on the Analytic Hi-erarchy Process(AHP)with weighted indicators derived from a comparison matrix and expert ratings,the system calculates comprehensive scores for different gate types,facilitating the ranking of al-ternative solutions.The results had shown that the established evaluation system for water storage control gate schemes could comprehensively express the basic functional characteristics and adaptabil-ity to external conditions of the control gate.The use of AHP method could apply a small amount of data information based on comprehensive consideration of multiple evaluation indicators for water storage control gates,and obtained more feasible decision-making results through expert scoring as the evaluation basis.
In order to research on the distribution law of groundwater in Huaibei coal mining collapse storage area,based on the collecting sufficiently of relevant literatures and date in the research area,Visual Modflow software was used to simulate and analyze the variation characteristics of groundwater flow field in coal mining collapse storage area from the perspective of studying the vari-ation of aquifer structure.The results showed that:1)when the coal seam is completely mined,the mine will no longer drain,and the porewater level of the loose layer that is drained due to the drainage of the coal mining pit will gradually rise under the condition of rainfall recharge and river recharge,but it can not recover to the pre-mining level.2)The drop of groundwater level caused by mine drainage cannot be restored to the initial pre-mining flow field under natural conditions,but a subsidence lake is formed in the collapsed area,and the fissure karst water receives continuous in-filtration and recharge of lake surface water in the subsidence area and porewater in the loose layer through the vertical network water-conducting fracture zone.The rise and overflow of fissure karst water level in each collapsed storage area resulted in the formation of several local water mounds.The study on the distribution of groundwater flow field in coal mining collapse storage area after pit closure can provide scientific basis for the comprehensive utilization of groundwater resources in coal mining collapse storage area.
基坑防渗支护体系设计与施工是工程建设关键环节,为解决安徽省六安市临淮岗复线船闸工程在汛期面临高洪水位作用影响导致基坑涌水的问题,在下游纵向围堰工程采用了一种以双排钻孔灌注桩、高压旋喷桩、混凝土防渗墙与箱涵相结合的围堰结构.双排桩与混凝土防渗墙形成围堰结构基础与上部填土箱涵结构连接承担交通荷载,并阻挡临航道洪水;混凝土防渗墙布置于双排桩中间,以确保钻孔灌注桩与高压旋喷桩连接部位在交通荷载作用下产生裂缝时不发生基坑渗漏.应用结果表明该技术有效解决了施工场地狭窄时防渗支护体系布置困难以及富水条件下挡水围堰结构不稳定和基坑渗漏等难题,具有经济、社会、环境等效益显著以及安全可靠的优点,可为类似工程设计和施工提供思路与参考.
为进一步从指标层面挖掘旱灾风险评估系统中不确定性信息向确定信息层次转化的关系,从差异度系数物理意义的角度出发分析推导出新的差异度系数取值分段函数,再与减法集对势进行误差对比,进而找到差异度系数求值公式最合适参数m.将其应用于2013-2017年宿州市旱灾风险评估系统指标层面的识别与诊断中,准确地获得了研究区旱灾风险评价系统中的不利因子,研究为评价指标动态总体发展趋势及进一步识别脆弱性指标因子提供了新的有效途径.
河道的回水地带常年受河道水流迎流顶冲影响,岸坡冲刷严重易崩塌,影响岸坡安全.以涡河县义门镇涡河左堤崩岸段应急加固工程为例,采用吨袋垫坡+膜袋自密实混凝土护坡技术对崩岸段进行加固处理有效解决了水下护岸边坡因水流冲刷引起的变形与坍塌问题,效果良好,可为类似工程施工提供参考.
为优化大体积混凝土温控方案以避免大体积混凝土因内部水化反应放热导致温度裂缝产生,以凤凰颈泵站改造工程为例,基于有限元方法使用MIDAS FEA软件通过对不同温控方案(四种冷却水管布置方案)的大体积混凝土进行温控数值模拟计算获得大体积混凝土内部的温度场、应力场,并对现场监测点实测温度变化与模拟结果进行比较,大体积混凝土内部温度先迅速上升,80 h后逐渐下降.综合对比四种温控方案最高温度及最大应力,方案二为相对最优方案.
既有泵站增容工程基坑一般存在距既有建筑物近、紧邻河道、地质条件复杂等特征,易出现施工安全问题.结合谢村排涝泵站增容工程泵室基坑施工,针对可能存在基坑失稳和影响既有建筑物等问题,通过对工程资料分析,优化了混合支护方式、考虑外河水条件的降排水、基坑变形监测分析的施工控制方案.该方案基坑降排水措施效果良好,既有建筑物变形满足设计要求,达到了预期效果,成果可供类似工程参考.
随着地下穿管工程日益增多,地下管道施工引发的堤防安全问题屡见不鲜,研究大直径管道穿越富水砂层对堤防稳定性及变形影响十分必要.选取某引水管穿越淮北大堤工程为例,通过对顶管穿越堤防进行数值模拟,分析顶管穿越富水砂层对堤防渗透稳定和边坡抗滑稳定的影响,并在顶管施工过程中选取地层受到扰动敏感区域开展土体内部水平位移和表面沉降实时监测.结果表明:顶管穿越富水砂层堤基对堤防渗流及边坡抗滑稳定有一定影响,但总体满足规范要求;顶管施工造成迎水侧区域沉降较明显,管道两侧4～5 m范围内土体受施工扰动出现水平位移;大直径管道采用顶管方式施工对堤防安全有一定影响,施工过程中要加强对堤防的安全监测,施工前后可采取注浆、设置防渗墙等措施消除或减轻顶管施工造成的不利影响.
为了解决目前部分农村饮水安全工程中仍存在的水源污染严重、水质达标率低以及水质检测能力不足等问题,进一步提升农村居民饮水条件,对纳米科技在水处理方面的研究进行了综述.纳米科技在净化水源、提升饮用水质、水质检测设备改进等方面提供新的解决思路,在未来的农村饮水安全工程中将展现出巨大的应用潜力.
本文以龙感湖国家自然保护区、华阳河湖群省级自然保护区为研究对象,建立了适合提取长江中下游湖区地物变化特征的分类方法.该方法的数据源来源于高效稳定的高分一号WFV遥感影像,采用人工神经网络、随机森林、支持向量机、最大似然、最小距离、马氏距离6种方法对分类结果进行空间和精度对比分析.人工神经网络分类法更接近湖区地物实际分布情况,总体精度和kappa分别为92.35％和0.8933,两者参数均高于其他分类方法.结果表明人工神经网络分类法在长江中下游典型湖区地物分类时适用性相对较好,能够更准确有效地提取湖区地物特征信息.
基于统筹思维和系统化管理理念,结合宿州市宿东闸2021年度在水闸省级标准化管理工程创建中的实践经验,针对工程管理机制、组织保障、技术支撑、监管维护等方面分析水闸标准化管理创建工作中存在的问题,提出了强化组织保障、完善系统管理机制、运用统筹思维转变管理理念、稳定维养经费投入等切实提高基层水闸管理水平的方法和措施,以期最大限度地提高水闸单位资源的利用率和管理功效,发挥工程整体效益.
为探究泰森多边形法在小流域面雨量计算中的适用性,以地处江淮丘陵区适宜进行产汇流机制等水文基础理论研究的典型闭合小流域花山流域为例,结合流域现状站点分布和地形特点,选取流域多年面雨量、典型场次与典型日面雨量三种不同降雨量级实例,分别采用算术平均法、泰森多边形法和等值线法计算面雨量进行对比.年面雨量和场次面雨量计算中泰森多边法对比等值线法计算值相对误差小于1.00％,日面雨量计算值相对误差小于2.00％;算术平均法在典型场次面雨量样本中有40.0％的计算值相对误差大于1.00％,最大相对误差为-2.47％,在典型日面雨量样本中有36.8％的计算值相对误差大于2.00％,最大相对误差为9.38％.结果表明:不同降雨量级使用泰森多边形法计算面雨量比算术平均法更接近于等值线法计算值;算术平均法在降雨量较小时受局部降雨影响计算误差较大,在年面雨量计算时可以和泰森多边形法互换使用.
堨坝是徽州的主要灌溉工程,早在1700 年前的东晋时期就开始修建,绝大多数至今仍在发挥蓄水灌溉的效益,是宝贵的灌溉工程遗产.本文介绍了古代堨坝建设的资金、投劳筹措及灌溉水费的摊派和管理等制度,有助于人们了解古代徽州的水利建设与管理.
