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1.
汪庆元  史春华 《人民长江》2004,35(11):19-20
根据皂市水库需承担的防洪任务,考虑澧水流域梯级开发和尽量减少移民等因素,选定其特征水位为:正常蓄水位140.0 m,相应库容12亿m3;防洪高水位和设计洪水位为143.5 m,相应库容13.94亿m3;校核洪水位144.5 m,相应库容14.4亿m3;防洪限制水位125.0 m;死水位112.0 m.考虑到澧水与长江干流洪水遭遇的机率较多,洪水地区组成复杂,在澧水流域规划确定皂市承担7.8亿m3防洪任务的基础上,将坝高增加2 m(坝顶高程由146 m改为148 m)以获得1亿m3库容,作为稀遇超标准洪水的防汛紧急备用库容.对皂市水利枢纽在澧水流域中的防洪作用作了详细论述.  相似文献   

2.
老口航运枢纽的开发任务是以航运、防洪为主,结合发电,兼顾为改善南宁市水环境创造条件。水库的防洪库容主要考虑静库容洪水调节法确定,同时用动库容洪水调节法复核;防洪高水位采用静库容洪水调节法、动库容洪水调节法两种方法计算,综合两种方法确定的成果从偏安全的角度确定防洪高水位。  相似文献   

3.
采用由实测流量推求设计洪水的方法,分别以考虑棉花滩水库影响和不考虑棉花滩水库影响两种途径对青溪水库的设计洪水进行了分析计算.结果表明,棉花滩水库建成投入运行后对青溪水库的设计洪水有一定的影响,且对青溪水库防洪有益;青溪水库可以适当提高其汛限水位.  相似文献   

4.
黄河下游滩区防洪是当前中下游洪水调度的难点,研究利用小浪底水库拦沙期较大的库容兼顾滩区防洪安全十分必要。通过实测资料分析、数学模型计算,分析了黄河中游洪水分期特点及近期变化,提出了适宜的保滩流量和分期分级洪水保滩库容需求量,研究以小浪底水库为主的中游水库群应急保滩运用方式,分析了水库应急保滩能力。结果表明:扣除大洪水防洪所需库容,前汛期小浪底水库现状汛限水位235 m以上库容可保证5 a一遇“上大洪水”下游不漫滩,“下大洪水”因小花间无控制区来水量较大,故难以保证下游滩区洪水不漫滩;后汛期现状汛限水位248 m以上库容可保证10 a一遇洪水下游不漫滩。实时调度中结合预报小浪底水库提前预泄腾库,保滩能力可进一步提升。但随着小浪底水库拦沙库容逐渐淤满,水库兼顾下游滩区防洪的能力将逐渐降低。  相似文献   

5.
尾矿库排水系统是否能够顺利及时的将库内水排出是其发生安全事故的一个主要因素,因此尾矿库排水系统的排水能力对其安全运行尤为重要。以DCG尾矿库增容设计工程为例,对尾矿库不同运行工况下进行洪水计算与调洪演算,并分析了不同运行工况下尾矿库拟定排水系统的排水能力,计算与分析结果表明:在不同运行工况下,尾矿库的排水系统均能将设计频率下入库内洪水安全有序的排出,调洪所需库容小于有效库容,对应工况下出现的最高洪水位低于相应坝顶标高,不会出现洪水漫坝现象,尾矿库拟定的排水系统在不同运行状况下能够满足防洪排水要求。  相似文献   

6.
水库汛限水位设计与运用概率统计分析方法   总被引:1,自引:0,他引:1  
考虑水库运用情况,一些水库由于水资源利用等因素,实际运行过程中多数年份汛期大洪水到来前水位低于设计汛限水位,即防洪起调水位低于设计值,增加了部分调洪库容,提高了防洪调节能力。考虑设计汛限水位出现概率进行汛限水位设置,在规划设计时通过概率分析可采用起调水位低于设计汛限水位对设计洪水进行调节从而降低坝高;对已建水库分析抬高汛限水位增加兴利库容、提高水库调蓄供水能力。在保证工程安全前提下,取得更经济的设计和运行方案。  相似文献   

7.
以棉花滩水库为例,在不降低年防洪标准的前提下进行汛限水位分期优化调度。采用传统水文频率分析法推求分期设计洪水,分期洪水组合概率应与年洪水概率一致;建立分期设计洪水频率与相应防洪库容的两变量序列,根据拟定汛限水位的防洪库容插值求得防洪风险率;在分期防洪风险率组合满足年防洪标准的前提下,根据发电、调洪规则及其它约束条件进行长系列模拟,对各分期进行风险和效益转移,寻求整体最大效益。结果表明:汛限水位前汛期取168.78 m、后汛期取169.58 m,防洪风险率分别为1.217%、0.783%,组合风险率为1.99%;与年防洪标准2%基本一致,同时具有较大的兴利效益。  相似文献   

8.
李庆 《小水电》2004,(6):40-41
1 工程概况河南省信阳市鲇鱼山水库主体工程有主坝、副坝、溢洪道、泄洪灌溉 (发电 )洞、水库电站等。水库防洪标准按百年一遇洪水设计 ,五千年一遇洪水校核。死水位 84m ,相应库容 0 15亿m3 ;防洪起调水位 10 6 0m ,相应库容 4 6 8亿m3 ;兴利水位10 7 0m ,相应库容 5 1亿  相似文献   

9.
高切林公式在计算中小型水库水位平溢洪道底无闸门控制情况下的水库最大溢洪流量时,因方法简单方便,在我国已被广泛采用。但在现有水库的防洪调度中,常遇到以下二个问题:(1)调洪库容较小的水库,遇到较大洪水时,要以水库现有溢洪道的最大泄量为控制条件,计算出要予留多少防洪库容,才能保证水库安全渡汛,(2)在予留防洪库容量明显偏小的情况下,根据天气预报,有较大洪水出现,此时需提前掌握溢洪道的最大泄量,以便决定是否要采取相应的措施。要解决好上述两个问题,如用正规的试算法,需经多次试算,工作量很大;用半图解法则因入库洪水经过予留防洪库容后,  相似文献   

10.
李卫峰 《陕西水利》2011,(5):122-123
防洪调节计算设计中包括了由流量资料推求设计洪水过程线和由暴雨资料推求设计洪水过程线。经过分析比较,选择两者之中洪峰流量较大者作为设计洪水,再运用试算法进行调洪计算,即可计算出合理的设计洪水位、防洪库容、校核洪水位和调洪库容等。  相似文献   

11.
尾矿库坝体溃决演进规律的模型试验研究   总被引:1,自引:0,他引:1  
本文结合实际工程,在自主研发的尾矿库模型试验平台上完成了尾矿库模型的搭建,进行了由于坝体排渗系统失效致使浸润线持续升高而诱发的尾矿库溃坝模型试验。利用坝体位移跟踪测量系统对尾矿库坝体溃决的演进过程进行了观测,总结了整个试验过程中的溃决模式及破坏形式。结果表明,坝体整体呈逆流牵引型溃决模式,溃决破坏形式大致经历三个阶段:坝面沼泽化诱发张拉裂缝、流土与局部塌落、较大范围崩塌与滑坡,其中前两个阶段是崩塌与滑坡的诱发阶段。在流土破坏出现前会出现堆积坝局部渗水、坝体裂缝等现象,此时若采取有效措施迅速降低浸润线,可避免发生大范围流土破坏。崩塌与滑坡过程溃决量大、持续时间短,一般难以防范。将模型试验结果与数值模拟结果和尾矿库溃坝原型资料对比,三者吻合良好。本文提出的模型试验方法可以预测尾矿库溃坝过程以及对尾矿库溃坝事故进行反演分析。  相似文献   

12.
尾矿库排洪系统通常由进水构筑物和排水构筑物组成。文章介绍尾矿库排洪系统类型、工作方式及其特点与适用条件。尾矿库的排洪系统具有进水口多,水流流态复杂等特点,其水流形态与常见的水利工程泄水建筑物过流有较大的差别,如何选择尾矿库排洪系统,涉及尾矿库的安全及经济性。  相似文献   

13.
 水是影响尾矿库稳定性的最主要因素之一。对青海云天化磷石膏尾矿库进行了洪水条件下的防洪和渗流计算,并利用上述计算结果对其稳定性进行了计算分析。在计算过程中,针对磷石膏尾矿库的特殊性,提出了将防洪计算和渗流计算紧密结合起来的一种计算思路。结果表明,该尾矿库在其防排渗设施正常运行的工况下是安全的,但在其排渗设施失效的情况下则是不安全的,在实际运行中应当加强对排渗设施的监测与维护。  相似文献   

14.
根据尾矿库溃坝特征,引入泥流水力计算对尾矿库溃坝事故进行计算模拟,并将模拟结果与GIS工具耦合,从空间层面对溃坝事故进程和产生的影响进行动态预测和展示,从而建立尾矿库溃坝事故预警体系,为事故应急工作提供指导。以南水北调中线水源地支流老灌河流域为例,选取流域上下游两个典型尾矿库进行溃坝事故情景模拟,得出上游尾矿库溃坝事故影响范围55km,对该尾矿库下游3~5km处居民区有严重危害,事故影响时间约6~7h;下游尾矿库溃坝事故影响范围13km,主要破坏该尾矿库周边农业资源,事故影响时间约2h。模拟结果在验证本研究实用性的同时,为该流域尾矿库溃坝事故预警应急措施和流域日常安全管理提供决策支持。  相似文献   

15.
Stabilization ponds used for the treatment of piggery wastes accumulate sludge over time, which is commonly used in agriculture. The objective of this study was to evaluate the agronomic potential of this kind of sludge. The samplings were collected in two different phases. The first in two anaerobic ponds (AP1 and AP2) and in one facultative pond with 5 transverse baffles and, the second in the same facultative pond with aeration. The removed sludge of AP1 and AP2 was characterized as rich sludge in volatile solids and with low stabilization, there was a great accumulation of the total phosphorus in the sludge of AP2. The facultative pond presented greater retention of nutrients in the sludge in relation to the anaerobic ponds. The annual accumulation of sludge was 13.3 cm/year in the AP1 and 6.70 cm/year in the AP2, while in the pond with aeration this was on the average of 0.5 cm/year, due to the aeration regime. The sludge can be used as a fertilizer in agriculture, if the chemical characteristics of the soil are taken into account so as to avoid the accumulation of nutrients and damage to plants.  相似文献   

16.
上游法尾矿库溃坝事故致因分析及安全管理技术研究   总被引:2,自引:0,他引:2  
尾矿库是一种高势能的人造泥石流源,一旦发生溃坝事故,将严重威胁到库区下游居民的生命及财产安全.针对我国中小型上游法尾矿库数量多、安全度水平低以及发生事故的复杂性、多样性等特点,对导致上游法尾矿库溃坝事故发生的各路径进行分析、研究,同时根据各路径建立事故树分析模型,应用布尔代数法计算得出最小割集,确定导致溃坝事故发生的各基本原因事件结构重要度;最后,结合生产实际,提出了保障上游法尾矿库安全运行的综合管理技术措施.该研究结果可以为矿山企业在尾矿库日常管理过程中制定合理的安全防范措施提供参考,从而有针对性地消除各种事故隐患.  相似文献   

17.
In a study conducted between January–March 2001, the spatial and temporal distribution of bird species in four sewage ponds at Chepkoilel campus, Moi University, Kenya, were determined. The total bird counts were conducted thrice daily for 10 days in each pond, yielding a total of 120 observations for all four ponds. Observations were made on three distinct foraging guilds: divers, surface feeders and birds that fished from the shore. Twenty‐four species of birds belonging to 10 families were observed in the ponds. The pond number had a significant effect on the distribution of the mean number of birds for all species. The highest mean number of birds was recorded in the first sedimentation pond receiving raw sewage (Pond I), with the number of birds decreasing linearly to Pond IV. The highest mean number of bird species also was observed for Pond I, with the lowest number being observed for Pond III. Even when the results were adjusted for area, the pond number was still significant, although the order changed significantly. Under these conditions, the highest density of birds was observed for Pond II. This was significantly higher than for Ponds I or III, which exhibited non‐significantly different densities. Pond IV exhibited a significantly lower density that all the other ponds. The total number of birds increased with the number of species. The density of avian foraging guilds was found to be significantly higher in Ponds I and II than in Ponds III and IV, supporting our hypothesis that bird abundance and distribution is influenced by the treatment status of the influent sewage.  相似文献   

18.
Stormwater retention ponds are one of the principal methods to treat stormwater runoff. Analysis of residence time distribution (RTD) curves can be used to evaluate the capability of these ponds for sediment removal. Deflector islands have been suggested as a means of improving the performance of retention ponds, due to their diffusing the inlet jet. In this study, the effect of an island on retention pond performance was investigated using a physical model of an existing stormwater retention pond. The physical model is a trapezoidal pond having top dimensions 4.1 x 1.5 x 0.23 m and side slopes of 2:1 (h:v). Three different arrangements were studied. The results show that placing an island to deflect the influent to a stormwater retention pond does not improve pond performance, rather it stimulates short-circuiting. This unexpected behaviour, in relation to previous studies, is considered to be a consequence of the model pond incorporating sloping walls; which is a novel aspect of this paper.  相似文献   

19.
为分析随着尾矿坝坝高的增加,处于尾矿库高埋深条件下的尾矿料在地震作用下是否会出现液化现象或发生较大永久变形,选择尾砂土进行高埋深条件下不同围压400,800,1 200 kPa的动强度试验,并进行尾砂土液化影响深度分析。分析成果表明高埋深条件下尾砂土的动应力随围压的增加而增大,随固结应力比的增加而增大,变化规律和小围压下的变化规律基本相同;高围压条件下,围压对液化应力比影响较大,液化应力比随围压的增加而减小,但归一化较差。采用规范的尾矿料地震液化判别方法,在尾砂土较小干密度和低固结应力比条件下,中部尾砂土存在大概率液化可能,随着地震作用应力比随埋深的逐渐折减,底部尾砂土可以不考虑液化问题  相似文献   

20.
Polishing ponds are units conceived for the post-treatment of the effluents from anaerobic reactors, are designed as maturation ponds, and aim at a further removal of organic matter and a high removal of pathogenic organisms. The paper investigates the performance of four very shallow (H = 0.40 m) polishing ponds in series, with very low detention times (1.4-2.5 days in each pond), treating anaerobic effluent from the city of Belo Horizonte, Brazil. The system was able to achieve excellent results in terms of BOD and E. coli removal, and good results in terms of ammonia removal, allowing compliance with European standards for urban wastewater and WHO guidelines for unrestricted irrigation. The paper presents the values of BOD and E. coli removal coefficients, which were much higher than those found in conventional pond systems. No statistically significant difference was found in the effluent E. coli concentrations from a pond with low depth and low detention time, and another pond in parallel, with double the depth and approximately double the detention time. The results endorse the applicability of the system composed by UASB reactors followed by very shallow ponds in series, with low detention times.  相似文献   

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