抽水蓄能电站输水系统斜井开挖施工安全管理

在抽水蓄能电站中斜井开挖施工历来是一个难点。为保证高水头,斜井段多数采用50°倾角,一般都较长。陡倾角长斜井施工由于施工环境特殊,施工难度大,存在诸多不安全因素。斜井开挖安全管理是施工过程中的全过程安全生产监督、检查管理、安全控制。     

柳洪水电站长斜井开挖施工技术研究与实践

柳洪水电站压力管道下斜井分三个阶段施工,先是采用人工导洞、反井钻先导孔,实现导孔对接,再采用反井钻导孔扩挖,最后进行全断面人工开挖.通过对柳洪水电站长斜井开挖施工技术的研究及实践,取得了反井钻机开挖斜井导向孔与人工开挖斜井导洞成功对接、扩挖一次成形的成果,实现了水电史上反井钻机开挖大倾角长斜井历史性的突破.为我国水电领域大倾角、长斜井开挖积累了成功经验.     

复杂地质条件下长斜井反导井开挖

那邦水电站压力管道开挖断面小,斜井长、倾角缓,呈＂五平四斜＂阶梯状布置,采用合理的斜井开挖施工方案是关键。简述那邦水电站采用人工法开挖斜井反导井的缘由,介绍在复杂地质条件下小断面缓倾角长斜井反导井开挖施工方法和经验总结。     

黑麋峰抽水蓄能电站长斜井开挖施工

黑麋峰抽水蓄能电站引水斜井长449.054m,直线段长392.2427m,倾角为50°,开挖内径为9.5～10.1m。陡倾角大断面长斜井开挖是国内中间无施工支洞单长最长的斜井,引水斜井开挖是本工程建设控制性的关键项目,开挖难度大,工期紧,安全、质量要求高,尤其是安全问题更为突出。为了确保成功,中国水电十二局一分局组成了大断面长斜井开挖施工技术研究小组,通过对本课题的研究与应用,安全、高效、保质保量地完成2条引水斜井的开挖任务,在2007年10月16日至2008年1月15日2号引水斜井扩挖施工中,连续2个月月进尺96m,创国内斜井施工单段开挖长度最长的新纪录,积累了丰富的经验,为今后类似工程提供借鉴。     

反井钻开挖大倾角斜井导孔的工程实践

针对柳洪水电站压力管道下斜段洞身长、倾角陡、工期紧、地质条件复杂、安全隐患突出等问题,开挖中采用反井钻开挖斜井导孔与人工开挖斜井导洞对接技术,安全隐患少,施工效率高。介绍了反井钻开挖大倾角斜井导孔的施工程序、操作步骤和导孔纠偏措施。在反井钻施工中通过调整主副泵工作压力、转速,合理调整稳定钻杆分布等措施控制孔斜,取得了反井钻实际钻孔129 m、平均日进尺7.5 m、导孔钻头落在距斜井中轴线下方1.8 m处的良好效果,成功与人工开挖导洞对接。     

水利水电工程斜井施工技术综述

斜井是水电水利工程中的重要建筑物,施工难度天。本文以陡倾角、大直径长斜井为重点,综述了水电水利工程各种斜井的开挖支护、混凝土衬砌和灌浆施工技术,并重点对施工安全进行了详细论述,可供水电水截工程斜井施工参考。     

引水斜井开挖施工技术

斜井是水利水电工程中的重要建筑物,施工难度大,有明显的特殊性。本次研究引水斜井开挖断面呈直径6．7m的圆形,洞轴线与水平面夹角为55°,斜长272．207m。斜井开挖选用ALIMAK爬罐自下而上开挖导井,导井全部贯通后利用手风钻自上而下进行扩挖的施工方法。保证了施工安全、工程质量、工程进度,成为我局斜井开挖施工又一成功典范。     

桐柏抽水蓄能电站陡倾角大直径长斜井开挖施工技术

桐柏抽水蓄能电站斜井开挖直径10 m,衬砌直径9 m,倾角50,°两条斜井长均为413.12 m。斜井正反导井同时开挖,贯通后一次扩挖成型。反导井开挖采用ALIMAK爬罐。斜井扩挖采用扩挖平台系统和运输小车系统。结合桐柏工程,介绍爬罐的使用、爆破点火方式、台车牵引的安全措施等,并对陡倾角大直径长斜井先进施工技术及施工中的问题进行总结。     

抽蓄斜井开挖扒渣工序关键技术研究

以福建某抽水蓄能电站斜井开挖施工作为案例,着重对斜井开挖中采用机械设备完成斜井开挖中扒渣的环节进行可行性和实操性进行研究,内容包括:设备型号选择、平衡配重、安装流程、运用流程、经济性对比分析等。着重阐述斜井采用机械化扒渣施工关键点,以此弱化循环工序中人的不稳定因素,减少安全风险,缩短斜井开挖循环的作业时间,推动我国的斜井施工安全性得到进一步的提升。     

西龙池抽水蓄能电站大坡度超长斜井开挖施工技术

西龙池抽水蓄能电站引水斜井长756.59m,倾角56°或60,°是大坡度超长斜井。斜井开挖采用阿里玛克爬罐自下而上打导井和反井钻自上而下打导孔再反拉导井技术,并设施工支洞。施工中针对导洞位置选择、扩挖掌子面设计、钻机定位、测量工艺、贯通精度、爆破方式等,采取了一系列的技术措施,安全优质地完成了斜井施工。     

生物预处理技术在嘉兴地区给水厂的应用比较

对嘉兴地区主要给水厂近年来应用立体弹性填料、LT型悬浮球填料、YS型悬浮填料、卵石填料等的生物预处理工艺从填料及配套设施、工艺运行参数、运行效果、成本等方面进行了比较.认为弹性填料生物预处理更适用于低浊(50 NTU以下)、低氨氮(1.5 mg/L以下)原水,LT型悬浮球填料生物预处理适用于低中浊(100 NTU以下)、低中氨氮(2.5 mg/L以下)原水,YS型悬浮填料生物预处理及"SAF"滤池对低浊、中高氨氮(2.5 mg/L以上)原水有较好的适应性.最后探讨了弹性填料存在的短流、积泥,悬浮填料存在的部分填料流化不均匀,富氧的生物工艺单元内水生动物泛滥等问题.     

中国部分河口及其近海水域缺氧现象研究

对长江、珠江等河口及其近海水域缺氧现象与影响因素进行研究,结果表明,主要分布于长江与珠江河口及其邻近海域的缺氧现象,夏季(6—8月)达到最盛,秋冬季消失;长江口的缺氧区域主要位于30.75°N~32°N,122.5°E~123.25°E附近海域,具有南北2个缺氧中心;珠江口缺氧程度相对较轻,缺氧区域主要在广州黄埔区河段至虎门水域和伶仃洋;辽河、钱塘江、海河等河口区域也时而出现零星的缺氧现象;水体缺氧受控于多项环境要素,物理层化作用是缺氧产生的最初诱因之一,陆源污染物的分解则是重要的耗氧负荷;各河口区特征各异,潮汐、洋流、营养盐、叶绿素a等要素对缺氧区的范围、程度和持续时间影响程度不一。     

无资料流域水文预报(PUB计划)研究进展

无资料流域水文预报，简称为PUB(Predictions in Ungaugecl Basins)，从2003年7月开始成为国际水文科学学会新的国际水文十年计划主题．文中首先简述了PUB计划的主要研究内容，然后回顾了国际和国内已有的PUB研究进展，最后展望了对水文学发展有重要意义的几个PUB前沿研究，包括不确定性研究、对水循环各个环节因素的预报和对无资料流域水文过程的预报。     

Trends in ecological river engineering in Korea

Ecological river engineering can be defined as the design and implementation of river works and river restoration works for the benefit of human society. It also guarantees the sustainable ecological functions of a river, such as its habitats and self-purification of its water. It is currently in the beginning stages in Korea, utilizing scientific knowledge on the processes of aquatic ecosystem degeneration and a methodology for solving the ecological problems in artificially altered rivers currently under development. The changes in river management and work practices in Korea may be best explained with a chronologically progressing sequence of ‘Natural’, ‘Disaster-prevention’, ‘Occupied’, ‘Park’, and ‘Close-to-nature’ rivers. Since the 1960s, the focus on river management and work has shifted from flood control only, to both flood control and riverine habitat conservation and restoration. Five research topics have been selected for this article, and the progress of each research area is briefly described with a representative picture in each topic. They are as follows: (1) flow resistance due to vegetation, (2) environmental flow, (3) floodplain vegetation modeling, (4) small dam removal, and (5) river restoration. For the future prospects of research on ecological river engineering in Korea, a necessity of further research on floodplain vegetation recruitment and succession, which can explain the so-called ‘white river’ and ‘green river’, is underlined, among others. Finally, two ongoing large research programs on river ecosystem restoration, of which are sponsored by the Government of Korea, are briefly introduced, followed by the introduction of a near-prototype experiment facility recently completed mainly for research on ecological river engineering.     

北京某学校雨水利用设计

以北京市某中学为例,介绍一种学校雨水利用的方法。根据校区水量平衡计算结果,对利用校园内汇集的雨水作为冲厕、绿化和景观用水等进行设计;采取相应的技术措施,对雨水径流的污染进行控制,保障所利用雨水的水质达到要求,并采用生态净化的方式,使学校景观水体循环起来。虽然雨水利用工程投资较高,但其社会和环境效益显著。     

Changes in urban stream channels in Zimbabwe

Although channel change has been documented downstream of urban areas there have been few previous studies which have focused upon the spatial variation of erosion and upon examples of such channel change in tropical areas. In the Avondale stream basin, which includes part of Harare the capital of Zimbabwe the way in which the channel network has evolved from the extensive dambo system in the period 1891 to 1984 is reconstructed showing that drainage density which was initially between 0.35 and 0.80 km km^?2 has increased to 3.15 km km^?2 including stormwater drains. Characteristics of erosion of the modified urban channels are described and the downstream reaches indicate an average channel widening of 1.7 times involving average rates of bank erosion of 0.33 m per year. Peak discharge is estimated from channel characteristics to be increased to two times former values and it is concluded that channel type and the relationship of channel change to the accommodation of peak discharges requires further research.     

Lake—Wide Seasonal Changes in Limnological Conditions in Lake Michigan in 1976

Data collected on lake-wide cruises in 1976 were used to study seasonal and vertical variations in water temperature, transparency, chlorophyll a, and nutrients in Lake Michigan. Data were analyzed according to subsets corresponding to the northern and southern open lake. Comparisons (t-tests) of data from the open lake indicated that the average water temperature was cooler and average water transparency was greater in the northern lake than in the southern, but with the exception of total phosphorus, average nutrient concentrations did not differ between the northern and southern parts. It was found that physical-chemical characteristics of nearshore and Straits of Mackinac stations differed significantly from open lake stations. Seasonal phytoplankton dynamics in the open lake were related to seasonal and vertical changes in silica and nitrate nitrogen. The spring phytoplankton bloom occurred before the lake was strongly stratified thermally. After thermal stratification was well developed, epilimnetic concentrations of chlorophyll a decreased, probably due to some combination of nutrient limitation and zooplankton grazing, and maximum chlorophyll a concentrations were found below the thermocline. Epilimnetic silica concentrations decreased after thermal stratification and diatoms were replaced in the phytoplankton assemblage by green and blue-green algae in late summer. Total phosphorus averaged only 8 μg/L on a lake-wide basis and thus only small but significant reductions in absolute concentration can be expected from phosphorus control programs. However, over a period of several years, these small reductions in concentration may be difficult to verify from total phosphorus measurements which have relatively large sampling errors and variances.     

水利高性能计算的进展

针对水利信息化对精细模拟与高性能运算提出的愈来愈高的要求,在简单介绍高性能计算的硬件、软件环境及其在水利上的几个应用实例后,着重介绍了并行有限元法、并行边界元法的一些进展以及网格技术的最新进展。指出从网络到网格是高性能计算发展的最新方向,应以网格平台支持、促进水利信息化进程。     

中国内地水库淤积的差异性分析

为了解水库的淤积现状,根据115座具有代表性的中国内地水库淤积资料,对这些水库按类型和区域进行统计分析,结果表明,中小型水库比大型水库淤积严重,不同流域水库淤积的空间差异明显,黄河中下游地区水库淤积比例最大,西南地区水库年均淤积率最大。截止到2003年,根据代表性水库淤积的计算结果推算出中国内地水库的平均淤积比例约为20%,库容年均淤积率为0.76%,相当于每年损失1座库容近42.3亿m3的超大型水库。     

我国水库大坝土工膜防渗工程进展

为促进我国水库大坝土工膜防渗工程的健康、快速发展,对其发展历程进行回顾、梳理。总结了将土工膜用于水库大坝防渗的优点,即防渗性能高、适应变形性强、施工方便、质量易于控制、工程整体造价低。指出尽管已建成的大中型土工膜防渗工程运行正常,但土工膜仅在我国中小型工程中应用广泛。通过对比国内外水库大坝土工膜防渗工程的发展现状,分析了国内外发展差距较大的原因,即缺乏国际交流的外部环境,缺乏自主研发的内部动力,以及缺乏规范的适时认可。认为随着建设经验和技术储备的积累,科技成果传播的畅通迅速,从业人员对该项技术的认识深入,我国水库大坝土工膜防渗工程具有较大的经济、社会效益潜在优势。