寒冷地区电站长距离输水明渠冬季运行方式探讨

通过大量工程资料收集和类似工程经验分析,对寒冷地区引水式水电站长距离输水明渠在冬季各种输、排冰运行方式的适用性进行了对比分析,着重对结冰盖运行方式的建筑物布置、流量控制和水位控制等进行深入分析和研究,提出了完整的分段壅水结冰盖输水方式的输水渠道建筑物布置、水位运行控制的设计和运行控制方法,消除了寒冷地区电站输水长明渠冬季运行中的冰冻危害问题,并成功运用于实际工程设计和运行。     

城市小区雨水渗透方案设计

结合北京某新建小区工程实例,对小区雨水渗透方案的设计方法和要点进行探讨,提出了适合我国北方地区的"高花坛+低绿地+植被浅沟、渗透沟"雨水综合渗透系统,用图例说明设计方案,并对其计算方法和技术经济分析作了探讨。     

宁夏东干渠冬季输水可行性初探

宁夏金积供水工程通过河东灌区东干渠输配水。随着供水量的日益增大,冬季进行补水已成为当务之急。为确保冬季渠道安全运行,解决渠道冬季运行过程中出现的问题,结合2010--2011年度运行情况进行了探讨,结论认为,冬季利用东干渠补水是可行的。     

山前水电站冬季运行的措施

我国北方寒冷地区的引水式电站，冬季运行的最大困难是冰害问题。山前水电站地处河北省北部，海拔４４０ｍ，为一无调节引水式水电站，装机２×８００ｋＷ＋１×３２０ｋＷ，引水渠２１００ｍ，尾水渠１０１０ｍ。建设电站时，没有考虑冬季防治冰害问题，投产后由于缺乏冬季运行的经验，致使从１９８２年投运至１９８８年，冬天自１１月２０日至翌年３月２０日约１２０ｄ时间停运，造成水力资源的浪费，电站经济效益受到很大影响。为了解决冬季发电问题，我们认真总结了以往的经验教训，针对电站的实际情况并学习外地经验，探讨可行的措施。…     

季节冻土区梯形混凝土渠道冬季停水与过水运行方式对温度场的影响研究

针对西北地区输水明渠易发生冻胀破坏的问题,依据热传导和水分迁移理论建立冻结期渠基土温度场,以分析渠道内过水对温度场分布的影响为目标,以新疆玛纳斯河四级水电站引水渠为典型案例,应用有限元软件进行温度场的模拟,并将结果与相关文献中的数据及破坏类型进行比对,验证模拟的合理性。结果表明:渠道内是否过水对渠道的温度场有显著的影响,主要是其温度场的分层发生变化且其温度线也出现了强烈波动。经实地观察发现,输水明渠渠基土体易产生较大的冻胀变形导致衬砌板胀裂、隆起及滑塌等破坏十分严重的位置与模拟中温度场发生变化的位置基本一致,且满足误差要求。用冻结期渠基土温度场变化来预测输水明渠发生冻胀破坏的准确位置具有很大的参考价值。     

平原圩区除涝排水系统实时调度中的神经网络方法研究

本文为平原圩区除涝排水系统建立了一个实时调度模型，其优化模型部分为NLP-NLP模型，为求解该优化模型，本文采用神经网络优化算法，可加速收敛.模型和解法在四湖地区应用效果良好。     

小型电站冬季运行冻害与防范措施

1概述1.1电站基本情况党河上游三级水电站(河道引水式电站)位于甘肃省酒泉市肃北县,海拔约2800~3000 m,冬季严寒,河道冰冻严重。水电站主要建筑物由引水枢纽、引水暗渠、压力前池、压力管道、厂房、尾水渠道、泄水陡坡、升压站等组成。每年冬季运行时间长,运行环境复杂。通过多年运行实践,摸索出一系列工作措施,可有效保证冬季运行安全。1.2冰情情况党河冬季水量小,来水流量一般在5~10 m^3/s。河道内冰凌严重,行凌始于头年10月,终于翌年3月。     

Performance evaluation of subsurface wastewater infiltration system in treating domestic sewage

This study was to investigate domestic treatment efficiency of a subsurface wastewater infiltration (SWI) system over time. The performances of a young SWI system (in Shenyang University, China, fully operated for one year) and a mature SWI system (in Shenyang Normal University, China, fully operated for seven years) under the same operation mode were contrasted through field-scale experiments for one year. The performance assessment for these systems is based on physical and chemical parameters collected. The removal efficiencies within the young system were relatively high if compared with the mature one: for biochemical oxygen demand (BOD), chemical oxygen demand (COD), suspended solids (SS), ammonia nitrogen (NH(3)-N) and total phosphorus (TP) were 95.0, 89.1, 98.1, 87.6 and 98.4%, respectively. However, the removal efficiencies decreased over time. The mean removal efficiencies for the mature SWI system were as follows: BOD (89.6%), COD (87.2%), SS (82.6%), NH(3)-N (69.1%) and TP (74.4%). The results indicate that the mature SWI system successfully removed traditional pollutants such as BOD from domestic wastewater. However, the nutrient reduction efficiencies (including NH(3)-N and TP) decreased after seven years of operation of the mature SWI system. Meanwhile, the SWI system did not decrease the receiving surface water quality.     

Evaluation of two stormwater infiltration trenches in central Copenhagen after 15 years of operation

Two stormwater infiltration trenches were installed in 1993 in an area in central Copenhagen. The system was monitored continuously for almost three years after establishment, and a small reduction in performance over that time, possibly due to clogging, was noted. A new study was conducted in 2009 to see whether the reduction in performance has continued and to determine how the system performs today. Water levels in the trenches were monitored for almost 4 months, and from this period seven events were selected to analyse the infiltration rate. A comparison with similar analyses on storm sequences from the first 3 years of operation shows that the infiltration has decreased since the establishment of the system 15 years ago. The decrease is statistically significant (p<0.01). A clogging model was fitted to the data and predictions were made for future performance. The results show that the system will discharge around 10 times more annual overflow to the sewers after 100 years of operation compared to the initial volumes, if clogging continues at current rates. This corresponds to 60% of the total runoff from the area. The results show that clogging and proper maintenance are important factors to consider when implementing stormwater infiltration trenches.     

寒旱区碾压混凝土重力坝运行性态分析

新疆北疆碾压混凝土坝是国内外在极端恶劣条件下修建的第一座百米级全断面碾压混凝土重力坝,工程已正常运行12 a,监测数据表明:坝体上部混凝土温度已接近准稳定场,腹心混凝土温度降至稳定温度场还需10～15 a;高水位运行至今,坝基及坝体水平位移均向下游移动,对比同类型工程,本工程水平位移在正常范围内。通过建立回归模型,分析得出温度及水位是影响横缝开合度及坝体水平位移的主要因素,时效位移年变幅均逐年减小,且变化速率逐渐降低,呈收敛趋势。大坝总渗流量在水位基本保持一致时逐年降低、排水孔加密后扬压力降幅明显。越冬层层间温度、渗透压力均满足规范及设计要求,新旧混凝土结合完好,工程实施的温控措施合理有效,高水位运行后,大坝是安全的,成果对严寒寒冷地区的工程设计、建设及运行管理具有重要的指导及借鉴意义。     

严寒地区小型水电站闸门冬季运行措施的探讨

结合严寒地区小型水电站不同类型闸门冬季运行的条件,分析冬季运行的影响因素,提出防范应对措施,保障安全运行.     

典型长距离调水工程冬季冰凌危害调查及分析

以某长距离调水工程为研究对象,基于原形观测资料分析渠道冬季冰情发展规律和存在的冰凌问题。介绍了渠道和建筑物布置特点、不同冬季气象特点和冬季输水运行方式,分析了流冰期、封冻期、开河期的冰情现象,不同年份和空间上的冰情分布特征,总结了长距离输水渠道冰情生消演变的基本规律。基于典型冬季渠道出现的特殊冰凌灾害,列举了冰塞、泵站前池水位下降、分水口流量降低、仪器设备读数失真、渠道衬砌冻胀等冰凌影响事件,分析了气象条件、水力条件和工程布置特点对冰凌危害出现的影响。从调度、工程措施出发,在不同冰期阶段,针对不同渠道和建筑物位置,提出集防、拦、扰、捞、排一体化的冰凌防护措施,为长距离输水工程冬季冰期安全高效运行提供技术保障。     

Analysis of rainfall time series with regard to temporal disaggregation for the use in urban hydrology

The temporal resolution of rain data recorded by national weather services is often lower (10-min resolution) than the data needed for rainfall-runoff simulations (1–5 min resolution). However, the time series are sufficiently long for statistical analysis. The goal of the project presented here is to develop a procedure that disaggregates the 10-min rainfall data of the Swiss Meteorological Institute (SMI) to 1-min time resolution. The aim is to implement the procedure in a computer program which can be used by practitioners for generating high resolution rainfall time series at a specific location. In a first step the 1-min data and the 10-min data of two rainfall time series in Switzerland (Heiden, Lucerne) were compared to find characteristic patterns and correlations. The position of 1-min peak within the 10-min interval, the ratio of 1-min peak to 10-min intensity as well as the distribution of the 1-min values within the 10-min interval were investigated. The analysis showed that the positions of the 1-min peaks within a 10-min interval were not uniformly distributed. The distribution depended on the temporal trend of the 10-min values. The ratio of 1-min peak to 10-min intensity seemed to tend towards a constant ratio for high intensities. The results for the two series (Heiden and Lucerne) were not significantly different. These first findings are encouraging with regard to developing a disaggregation to 1-min values which satisfy the accuracy needed in urban hydrology.     

The role of in situ unit operation/process infiltration treatment on partitioning and speciation of rainfall-runoff.

Management decisions regarding the potential fate and toxicity of anthropogenic metal elements requires a knowledge of metal partitioning and speciation as mediated by in situ control systems (ICS). This study focussed on Cd, Zn, Cu and Pb, common anthropogenic metal elements generated in the built environment and examined the influence of variable event-based hydrology and passive ICS by an engineered partial exfiltration reactor (PER) system on partitioning and speciation. The feasibility and efficiency of the PER as an in situ stormwater runoff control strategy to attenuate levels of metal elements was evaluated. Results indicate that higher rainfall intensity resulted in higher dissolved fraction (fd) values for influent Zn, Cu and Cd, but did not have a significant influence on partitioning of Pb. Speciation indicated that divalent fractions of Cd, Zn, Cu and Pb were changed marginally by the PER. Cu and Pb mainly complexed with organic matter in the influent, while carbonate complexes of these metals in the effluent significantly increased. The PER consistently and statistically reduced all loadings of Cd, Cu, Pb and Zn for all examined events, whether on a mass or concentration basis. As an unsaturated flow unit operation/process the PER can efficiently remove ionic or complexed forms of metal elements. Such UOPs are a potential quality and quantity ICS strategy for rainfall-runoff.     

三峡工程运行对洞庭湖区钉螺及血吸虫病的影响

三峡工程运行是否导致长江中下游血吸虫病蔓延问题引起了广泛关注。2003～2010年先后在洞庭湖区布置了26个螺情监测站,进行跟踪监测。监测数据表明, 2014年与2003年螺情比较,洞庭湖洲滩有13个监测点未查到钉螺,9个有螺监测点活螺平均密度降低了96.27%;2014年有螺点占总监测点的34％,有螺洲滩面积和分布范围正在快速缩小,洲滩钉螺向垸内扩散机率大幅减小。     

极端干旱区小城镇绿地土壤水分入渗性能研究——以阿拉尔市为例

为进一步促进阿拉尔生态城市建设和保证城市可持续发展,以阿拉尔市绿地土壤为研究对象,选取校园、市政、居民区、道路绿化带4个功能区绿地土壤,用环刀法测定土壤水分入渗过程并做了模型拟合和分析。结果表明:4个功能区绿地土壤水分入渗性能存在明显差异,稳定入渗率为道路绿化带绿地(0.31 cm/min)校园绿地(0.05 cm/min)市政绿地(0.02 cm/min)居民区绿地(0.01 cm/min);应用常用的入渗模型进行了拟合,通用模型及Kostiakov模型能较好地描述4个功能区的绿地土壤入渗特征,Philip模型在本区的适用性最差。研究结果为阿拉尔市绿地土壤的管理提供一定依据。     

珲春市农村饮水工程运行管理初探

为加快农村经济的发展，近两年来，国家对农村人畜饮水工程有了很大投入，仅2000年在珲春市就投入了170多万元兴建了四处农村人口饮水困难工程，工程是保质保量地建完了，可摆在我们面前的一大难题是工程管理问题。过去，珲春市也曾修建过30多处农村供水工程，可是……     

考虑降雨入渗的某矿区滑坡数值模拟分析

矿区坡体土质粘粒较少,在二次翻采、随意堆弃工况下,极易造成滑坡区土质疏松、加大土体的孔隙率。根据矿区滑坡坡体的工程地质及工况特点,考虑土体内应力场与渗流场之间的流—固耦合作用,采用有限元法,对比分析了某矿区滑坡体的边坡在降雨前、后的边坡安全系数.数值分析表明,考虑降雨入渗的情况下边坡安全系数明显下降.