鄱阳湖修河虬津水文站非一致性设计洪水研究

非一致性条件下设计洪水对水利工程的规划设计及防洪决策等具有重要意义。针对传统时变矩法求得每年一个非一致性设计洪水值难于直接应用到工程实际的不足,考虑影响径流的两项气象因素（降水量和气温）,并结合重现期的期望超过次数概念,选取修河虬津水文站1956-2014年年最大1、3、7、15 d和1个月的洪水系列,结合大气环流模式输出的降水量、气温统计降尺度成果,推求非一致性条件下虬津水文站多时间尺度下的设计洪水流量值,并与传统的不考虑系列非一致性的设计结果进行对比。结果表明：虬津站各时间尺度洪水流量系列位置参数均存在显著的非一致性。一致性条件下设计洪水流量和以气象因子为协变量的非一致性设计洪水流量存在显著差异,RCP4.5和RCP8.5情景下,各时间尺度20 和50 a重现期非一致性设计洪水流量值与一致性设计值相比分别减小了13.5%~32.6%（平均约26.4%）和15.3%~39.1%（平均约31.0%）。研究结果可为区域洪水灾害防治和洪水资源利用提供一定参考。     

水库预泄调度风险指标及方案优选模型的研究

水库预泄调度是水库防洪调度的重要方式之一，它可以提高水库防洪能力。为此，针对西大洋水库的具体特点，拟定了可能的预泄调度方案，建立了水库预泄调度多目标风险指标体系及方案优选模型，并进行了实际预泄调度方案优选的研究。结果表明：对于10年一遇的洪水，可采用200m^3／s进行72h的预泄，或者采用300m^3／s进行24h或12h的预泄；而对于20年一遇的洪水，可采用200m^3／s进行72h的预泄。研究为西大洋水库预泄调度方案的建立提供了可靠的依据。     

考虑非一致性条件的淮河干流洪水分析

环境的变化和不确定性导致水文序列表现出非平稳特征,基于一致性条件的洪水风险分析忽略了气候变化和人类活动等因素的影响,会低估洪水风险.研究采用GAMLSS模型作为边际分布模型,以降水作为协变量,对淮河干流部分重要水文站点的年最大1 d流量和年最大15 d洪量序列进行非一致性频率分析,探究非一致性条件下洪峰和洪量设计值的变...     

Flood Control in the Cuiabá River Basin, Brazil, with Multipurpose Reservoir Operation

Periodic flooding in the Cuiabá River Basin (CRB), which is located in the upper Pantanal region, in central-western Brazil, led to the construction of the Manso multipurpose reservoir and power plant. This study evaluates the influence of the Manso reservoir on the attenuation of downstream flooding specifically in the metropolitan area of Cuiabá, which is the capital city of the state of Mato Grosso. The flood routing provided by the Manso reservoir was simulated by means of the Puls modified method (level-pool routing method), and the translation of the flood wave during floodplain passage was calculated with the CLiv hydrodynamic model for critical hydrological events. It is demonstrated that the reservoir reduces the frequency of flood risk to downstream communities for return periods between 50 and 100 years. Despite the flood attenuation, other measures should be undertaken in addition to the reservoir operation to mitigate the impacts of flooding in a comprehensive and appropriate way. In particular, measures related to floodplain land use planning and management are important to ensure that the safety of the population does not exclusively depend on the upstream reservoir.     

基于时变矩模型的湄公河上游非一致性洪水频率分析

以湄公河上游为研究案例,基于清盛水文站1960-2019年逐日流量观测数据,采用时变矩模型进行非一致性洪水频率分析,探讨梯级水库建设对洪水频率的影响。结果表明：清盛水文站年最大日流量序列呈显著减小的非一致性特征;清盛水文站广义逻辑斯谛分布搭配均值具有线性趋势的模型拟合最优;与传统频率分析方法相比,时变矩方法计算得到的100年一遇设计流量随时间呈减小趋势,重现期随时间呈上升趋势。湄公河上游梯级水库尤其是糯扎渡水库运行后明显减小了清盛水文站100年一遇的洪峰流量,对下游防洪具有积极作用。     

小浪底水库防洪作用分析

根据黄河下游防洪工程体系现状,拟定了小浪底水库投入运行后的干支流水库调洪方式,分析了小浪底水库的防洪作用。结果表明,小浪底水库的兴建使黄河下游大堤的设防标准由现状的六十年一遇提高到千年一遇(即千年不用北金堤);使花园口百年一遇洪峰流量削减到16000m~3/s以下(即百年不用东平湖新湖区);使花园口22000m~3/s以下的较大洪水削减到10000m~3/s以下(即不用东平湖滞洪区);发生万年一遇洪水时,只需用北金堤滞洪区少量分洪即可;将三门峡水库对“下大洪水”的运用机率由十年一遇减少至百年一遇,各种级别洪水的蓄洪量均有较大幅度减少。     

金沙江中游与长江中下游洪水遭遇规律分析

按照《长江流域防洪规划》和《长江流域综合规划》的安排,金沙江中游已建及在建的6座梯级水库每年7月份共预留防洪库容17.78亿m³,配合三峡水库进行长江中下游防洪。基于金沙江攀枝花站和长江中游螺山、城陵矶、宜昌站的洪量和洪水过程并考虑泄水传播时间及区间来水过程,详细分析了金沙江中游洪水与长江中下游洪水的遭遇规律。研究结果可为金沙江中游梯级水库防洪调度方式的建立提供技术支撑,有利于充分发挥水库群的防洪效益。     

双库连通水库调洪演算的方法研究

该文以合肥市杜集水库为例,分析和研究双库连通水库受下游河道影响的调洪演算的理论方法,通过建立双库连通水库计算模型进行调洪演算;计算结果表明,该方法理论合理,操作性强,成果可靠,可应用于双库连通水库的防洪调度和调洪演算。     

论三门峡水库在黄河防洪工程体系中的作用

通过对三门峡水库运用40余年来社会效益、经济效益以及负面影响的论述，分析了三门峡水库在未来黄河防洪减淤工程体系中的作用和地位，讨论了潼关高程淤积抬升的主要原因及降低潼关高程的综合治理措施，指出了小浪底水库建成后，决定三门峡水库运用方式的主要因素仍是黄河下游和渭河下游的防洪减淤问题。同时，给出了三门峡水库不同运用阶段的水位控制运用指标的建议：①继续做好三门峡水库335m防洪水位和326m防凌水位运用的准备；②汛期平水期保持库水位不超过305m，当入库流量大于1500m^3／s，实施敞泄排沙，并控制北村断面1000m^3／s流量相应水位不超过310m；③非汛期运用水位原则上最高不超过318m，遇调水调沙等特殊情况，需要短时间调蓄时，最高水位不得超过320m，非汛期平均运用水位按照不超过316m控制；④实施渭河下游综合治理，降低潼关高程。     

三峡水利枢纽的设计洪水

在进行了大量分析研究后，认为三峡水系列采用Ｐ－Ⅲ型理论分布曲线进行拟合是合适的，采用１９５４，１９８２，１９８１年实测洪水作为设计洪水典型是可行的，安全的；采用的入库设计能反映三水库建成后的实际情况；各种时段洪量的期望概率，十分接近或销低于设计频率，能满足工程指定的设计标准；计算的可能最大洪水及校核洪炎为１１７５００－１２７０００ｍ＾３／ｓ，７天洪量６０７－６５２亿ｍ＾３１５天洪量可能最大洪水为１     

HEC-RAS洪水演进模型的应用

上游入库洪水在三峡库区向下游传播的过程中,受到库区的调蓄作用,洪峰削减明显。同时由于区间入流的影响,库区的调蓄作用被掩盖,这为研究洪水在库区行进中所受的调蓄作用带来了困难。应用在三峡库区建立的HEC-RAS洪水演进模型,模拟1989年-2000年间209场洪水在不考虑区间入流时向下游传播的过程,并检验洪水传播时间,其中洪水波行进时间用上下游洪水过程线的时间重心之差表示。按照库区5个水文站位置将库区分为4段分别检验。将HEC-RAS模型应用于三峡水库2006年和2007年蓄水期库区水位的模拟,结果表明,蓄水期水位变化过程得到了较好的模拟,对最高水位的模拟误差可控制在0.2 m之内。并应用该模型,分析和比较了库区4个部分对洪峰的削减作用。     

Optimal Operation of Multi-reservoir Systems Considering Time-lags of Flood Routing

Operations of multi-reservoir systems are nonlinear and high-dimensional problems, which are difficult to find the optimal or near-optimal solution owing to the heavy computation burden. This study focuses on flood control operation of multi-reservoir systems considering time-lags caused by Muskingum flood routing of river channels. An optimal model is established to jointly minimize the flood peak on the downstream flood control station for the multi-reservoir systems. A hybrid algorithm, Progressive Optimality Algorithm and Successive Approximation (POA-SA), is improved to solve the multi-reservoir operation model by modifying the POA. The POA-SA uses the DPSA to reduce the spatial dimensionality due to the multiple reservoirs, and adopts an improved POA to alleviate the temporal dimensionality caused by the time-lags of the Muskingum flood routing. Linear programming is then implemented to verify the solution of the POA-SA method with a linear approximation of the discharge capacity curve. The multi-reservoir systems of China’s Xijiang River is selected for a case study. Results show that the flood peak of Wuzhou station can be averagely decreased by 6730 m³/s (12.8 %) for the 100-year return period floods, indicating that the proposed method is efficient to operate the multi-reservoir systems and resolve the time-lags issues.     

献县泛区洪水演进数学模型研究

为研究献县泛区的洪水演进情况,以一二维非恒定流方程为控制方程,运用有限体积法进行离散,结合献县泛区地形资料及滹沱河流域的水文资料,建立了一二维耦合的洪水演进数学模型。采用滹沱河现状行洪能力下的实测水位对模型进行验证,结果基本吻合。在10、20、50 a重现期洪水来水情况下进行模拟计算,得到了不同口门相应的启用时间以及河道主要断面的水位过程图;比较了在不同洪水情况下,河道主要位置的堤高与相应洪水高水位以及泛区水位达到最大值的时间。 结果表明:随着重现期的不断变大,河道主要位置的水位都有明显升高,而且在20 a以上重现期下姚庄下游的河道水位逐渐高于河堤,出现漫堤情况。研究成果可为下一步防洪决策提供依据。     

小浪底水库过用初期三门峡水库防洪运用分析

小浪底水库建成投入运用，将大大提高黄河下游的防洪标准，也减轻了三门峡水库在黄河下游防洪，防凌中的负担，并为减少三门峡水库库区淤积创造了条件，在发生了“上大洪水”时，三门峡水库与小浪底水库联合运用，三门峡水库可分别采用敝泄方案，先敝后控方案和适时调控方式进行防洪调度，经计算并综合分析比较认为，“适时调控”方案为综合效果好的方案。     

柘溪水库防洪调度问题及应对措施

大型水库在流域洪水防御中发挥着重要作用,研究大型水库防洪调度中面临的实际问题,对于充分发挥水库防洪减灾效益、保障流域防洪安全和社会经济健康发展具有积极的现实意义。以湖南省资水流域的柘溪水库作为研究对象,分析了在自然、社会条件变化发展中柘溪水库防洪调度面临的4个新问题;针对这些问题开展研究实践,归纳了在实际调度工作中采取的5条相应防洪调度措施;以柘溪水库2016年"7·4"特大洪水防洪调度为例,论述了具体工作措施及取得的成效。指出水库防洪调度应以问题为导向,加强对影响防洪的因素研究,优化防洪调度措施,以达到充分发挥水库防洪减灾综合效益的目的。     

Comparison of Artificial Neural Network Methods with L-moments for Estimating Flood Flow at Ungauged Sites: the Case of East Mediterranean River Basin, Turkey

A regional flood frequency analysis based on the index flood method is applied using probability distributions commonly utilized for this purpose. The distribution parameters are calculated by the method of L-moments with the data of the annual flood peaks series recorded at gauging sections of 13 unregulated natural streams in the East Mediterranean River Basin in Turkey. The artificial neural networks (ANNs) models of (1) the multi-layer perceptrons (MLP) neural networks, (2) radial basis function based neural networks (RBNN), and (3) generalized regression neural networks (GRNN) are developed as alternatives to the L-moments method. Multiple-linear and multiple-nonlinear regression models (MLR and MNLR) are also used in the study. The L-moments analysis on these 13 annual flood peaks series indicates that the East Mediterranean River Basin is hydrologically homogeneous as a whole. Among the tried distributions which are the Generalized Logistic, Generalized Extreme Vaules, Generalized Normal, Pearson Type III, Wakeby, and Generalized Pareto, the Generalized Logistic and Generalized Extreme Values distributions pass the Z statistic goodness-of-fit test of the L-moments method for the East Mediterranean River Basin, the former performing yet better than the latter. Hence, as the outcome of the L-moments method applied by the Generalized Logistic distribution, two equations are developed to estimate flood peaks of any return periods for any un-gauged site in the study region. The ANNs, MLR and MNLR models are trained and tested using the data of these 13 gauged sites. The results show that the predicting performance of the MLP model is superior to the others. The application of the MLP model is performed by a special Matlab code, which yields logarithm of the flood peak, Ln(Q_T), versus a desired return period, T.     

An Adaptive Metropolis-Hastings Optimization Algorithm of Bayesian Estimation in Non-Stationary Flood Frequency Analysis

Global climate changing and human activities have altered the assumption of stationarity, and intensified the variation of hydrological process in recent decades. It is essential to make progress in accommodating appropriate models to the changing environment where non-stationary models are taken into account. The developing adapted Bayesian inference offers an attractive framework to estimate non-stationary models, when compared with conventional maximum likelihood estimation (MLE). As the inseparable companions of Bayesian inference, an efficient MCMC sampler are expected to be built. However, proper tunings are needed for the sampler to improve the performance by integrating adaptive algorithm and optimization method. A Bayesian approach with the adaptive Metropolis-Hastings optimization (AM-HO) algorithm is adopted to estimate the parameters and quantify the uncertainty in a two-parameter non-stationary Lognormal distribution model. To verify the performance of the developed model, simulation experiments and practical applications are implemented to fit annual maximum flood series of two gauges in Hanjiang River basin. From the point view of parameters estimation, both Bayesian and MLE methods perform similarly. However, Bayesian method is more attractive and reliable than MLE on uncertainty quantification, which provides a relative narrow intervals to be beneficial for risk analysis and water resource management.     

金沙江流域极端强降水分布拟合

极端降水的统计分布研究是当前国内外极端水文事件研究的前沿方向之一。根据金沙江流域45个气象站的长系列日降水资料,采用年极大值抽样方法建立了不同统计时段(最大1 d、最大3 d、最大7 d等)的降水极值系列,通过比选11种常见的概率分布函数确定了金沙江流域极端强降水的最优分布。对基于站点与面暴雨的2套极端强降水序列的频率分析表明,韦克比分布是拟合金沙江流域极端强降水发生概率的最优分布形式。     

抚顺县英守水库防汛抢逃险对策浅析

英守水库地处抚顺县东南部山区,是古城子河上游的一座中型水利枢纽工程。本文结合水库工程现状以及下游居民企事业单位的分布情况,从防汛抢险、逃险两个方面的预案应对措施安排上进行了探讨和分析,阐述了抢逃险工作安排的重点环节把控,为水库科学合理地进行防洪调度,安全有序地应对险情提供了技术支持。     

清江水布垭和隔河岩梯级水库防洪库容互补关系研究

采用同频率组成法和最可能组成法推求隔河岩水库的洪水地区组成,基于不降低设计防洪标准的原则推求了水布垭和隔河岩梯级水库防洪库容互补关系。结果表明,采用同频率组成和最可能组成方法,推求隔河岩水库设计洪水地区组成合理可行;当清江流域发生20~200年一遇洪水时,水布垭-隔河岩水库防洪库容具有近似线性互补关系,折算系数均值为0.63,其他重现期洪水的折算系数为1;不同典型年和设计频率对防洪库容折算系数的影响较小;在确保预留总防洪库容不少于10亿m³前提下,实现隔河岩水库汛期运行水位动态控制,与原设计各预留5亿m³方案相比,清江梯级电站年均汛期可增发电量9100万kW·h(+5.1%)。