辽宁省中小河流治理模式探析

文中在总结辽宁省中小河流治理经验的基础上,结合国内其他地区中小河流治理的相关经验及技术资料,对中小河流的治理模式进行了探讨,提出辽宁省中小河流治理工程建设应从单一防洪目标向多目标综合治理原则转变,重点考虑河道生态环境影响的生态型防护技术和河道景观技术,突出人水和谐的理念,并对适合辽宁省河道治理的几种模式和技术进行了分析、探讨。     

辽宁省中小河流治理适宜模式探讨

在总结辽宁省近期中小河流治理经验的基础上,通过对治理效果良好的项目进行研究,提出适合辽宁省中小河流具体情况的治理思路、机制及保障措施,为以后河道治理达到恢复河道自然生态,实现人水和谐的理念提供一定的借鉴作用.     

派潭河中小河流治理工程方案探析

中小河流治理不同于平原区河道,工程保护范围相对较小,堤岸较容易形成闭合,中小河流支流众多,河道纵坡较陡,植被生长茂盛,地理情况比较复杂,工程设计方案较多。以派潭河中小河流治理工程为例,结合设计原则以及各河段现状,提出对河道堤防进行加高培厚、裁弯取直、清淤疏浚等具体措施,符合中小河流治理原则以及生态保护原则。     

辽宁省中小河流治理存在的问题及对策

辽宁省河流众多,大江大河基本建成了蓄泄兼治的防洪体系,中小河流的防洪治理相对滞后,在辽宁省洪水灾害中所占比重极大,已经成为辽宁省防汛工作的隐患所在。文章对辽宁省中小河流治理过程中存在的主要问题进行了系统分析,针对我省中小河流特点提出了切实可行的治理对策,对中小河流治理有较好的借鉴意义。     

湖南省中小河流治理综述

针对湖南省中小河流现状，对中小河流治理存在的问题进行了分析，并提出了中小河流治理的规划目标。同时指出：中小河流治理应在确保防洪安全的前提下，着重突出生态治理的理念，尽量保持河流的自然形态；在工程设计上，堤线、河岸线要尽量沿现状河岸线布置，避免人为裁弯取直、缩短河道，尽量保护河道原有宽度，仅对河道宽度不够的个别河段进行拓宽，避免“渠化”行为。其治理理念可供其他中小河流参考。     

中小河流治理工程“十三五”总体规划保障措施及建议

为总结"十二五"期间河南省中小河流治理情况,对下步有治理必要性但尚未治理的项目能够被合理纳入省级项目储备库提供参考,做好全省中小河流近、远期规划筹备,继续推进流域面积200~3000 km2中小河流治理工作,进一步扩大治理范围,加强河道系统治理,恢复河道行洪能力,提高防洪排涝标准,改善农村水环境和用水条件,使治理范围基本覆盖所有具有防洪任务的中小河流。河南省水利厅组织开展了"十三五"中小河流治理工程总体规划编制工作,对确保纳入规划项目均能得以顺利实施具有重要作用。     

中小河流防洪治理河道宽度选择

中小河流治理结合城镇化发展成为防洪治理重要方向。因人类历史发展、上游建设水库、近年来雨水偏少等原因,北方地区中小河流下游河道往往断流,河道多被侵占或束窄。随着城镇化发展,中小河流河道治理项目增多,河道宽度的选择就成了防洪设计的难题。采用河相关系式确定防洪治理河道宽度,以满足防洪标准。     

浅析漯河市中小河道的治理

漯河市中小河流遍布全市各县,呈疏散状况分布。据统计,全市共有中小河流17条,境内河流总长度387.12km,境内流域面积约2641.2km2,境内堤防总长度356.58km。随着极端天气增多,中小河道在防汛抗旱排涝的作用日渐突现。由于此前在大河治理的同时,忽略了对中小河道治理。造成中小河道堤防等水利设施损毁严重。河道淤堵,河道内种植农作物等现象普遍存在,严重影响了河道的防洪、泄洪、排涝功能。因此,加强中小河流的治理,保证中小河流的防洪安全,是防洪工程建设的主要任务。中小型河道的管理仍存在管理体制混乱,没有专职管理人员,管理资金不到位问题,严重影响了河道及堤防的正常管理和维护。     

浅析中小河道综合治理的技术方法

新疆石河子市冰川融化形成的中小河流众多,最近几年随着经济的快速发展中小合理污染严重,在中小河道治理过程中综合治理方法效果最好,在综合治理当中既有化学治理方法,还有生态治理方法等。结合石河子市中小河流治理的经验,探讨中小河道综合治理技术方法的最近几年的发展、应用和效果,通过研究详细总结中小河道综合治理的技术经验,为彻底解决中小河道综合治理问题提供借鉴。     

辽宁省铁岭县中小河流生态治理措施

辽宁省中小河流较多,中小河流生态系统的健康与否,直接关系到依附于它而存在的各个物种的生存状态。因此,对中小河流生态系统的保护与研究是十分必要的。本文以辽宁省铁岭县恶龙河、亮沟河生态治理措施为例,阐述了恶龙河、亮沟河流治理中应采取的治理方法和措施,研究成果可供有关水利工作者在实践中参考。     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

浙江省水域调查录入系统的设计和应用

浙江省水域调查录入系统将调查数据与电子地图相整合,对分类水域数据进行统计计算,并对输入数据进行合理性和完整性检查,得到调查范围内现有水域的详细数据,实现了水域调查数据输入、计算、统计和查询的数字化管理,提高了工作效率和工作质量,为各地下阶段水域保护规划编制和水域管理工作提供了数据支持。对该系统的设计原则、功能和技术设计等作了介绍。     

基于CT-连续加荷水泥乳化沥青混凝土细观损伤规律研究

利用CT技术对水泥乳化沥青混凝土的细观损伤过程进行实时扫描观测,获得了混凝土试件在连续加荷下的CT图像。通过采用直观分析法、CT数分析法、CT数与损伤变量关系3种方法分析表明,水泥乳化沥青混凝土的破坏过程可分为压密、扩容、裂纹扩展、破坏4个阶段,同时混凝土在受压过程中具有韧性,在极限荷载之前各断面处于压密和微扩容的强化阶段,极限荷载之后混凝土从损伤到破坏发展比较平稳。     

浅谈天湖水电站水轮机运行故障及处理措施

简述天湖水电站投运以来各种故障的表现形式，分析其原因，提出了相应的处理方法及措施，并对合理利用国内外设备提出建议。     

Fish assemblage response to recent mitigation of a channelized warmwater stream

Various designs of low‐head dams are used to rehabilitate streams or forestall upstream channel incision after channelization. We report on the efficacy of using notched sills and grade control structures (GCS) to restore the fish assemblage in Luxapallila Creek, Mississippi. We tested the null hypotheses that habitat variables and species richness, evenness, and assemblage structure would not differ among: (1) a channelized segment with no modifications; (2) a channelized segment mitigated by the installation of sills and GCS; (3) a segment upstream of the installations and undergoing channel incision; and (4) an unaltered segment. Although habitat variables changed, neither species richness, evenness, nor fish assemblage structure differed between mitigated and channelized segments with both exhibiting less richness and different assemblage structures than the unaltered segment. Lack of differences in species richness between the incised and unaltered segments suggest that the GCS may have halted the negative effects of upstream channel incision before species were extirpated. Conspicuous habitat differences between the altered (channelized and mitigated) and unaltered segments were lack of backwaters and canopy coverage and finer substrates in the altered segments. Our results suggest a more comprehensive rehabilitation strategy is required in Luxapallila Creek. Published in 2003 by John Wiley & Sons, Ltd.     

NUMERICAL STUDY OF WAVE EFFECTS ON SURFACE WIND STRESS AND SURFACE MIXING LENGTH BY THREE-DIMENSIONAL CIRCULATION MODELING

1. INTRODUCTION Coastal and continental shelf regions are characterized by intensive interaction between wave and current. These regions are of great economic significance to mankind. Therefore, the modeling of wave and current as well as their mutual int…