生态护坡技术在板桥河治理工程中的应用

板桥河是南京市一条重要的通江河道,未治理段存在河道过水断面严重偏小、堤顶高程不足、堤身单薄、岸坡无防护等涉及防洪安全问题。板桥河治理工程采用格宾网箱挡墙、格宾网箱护垫、生态袋护坡、木桩防护、三维植被网草皮护坡等生态护坡技术。生态护坡技术在发挥岸坡防护作用的同时也起到逐步修复沿河生态环境的作用,使板桥河治理工程不仅是水利工程,也是一项修复生态、美化环境的景观工程。     

城镇河道治理中生态护岸方法分析

由于社会经济的快速发展带来了环境问题,使人们意识到经济建设必须与生态环保紧密结合,这就需考虑如何在建设中兼顾维护生态环境的问题。本文重点介绍人口密集的城镇河流岸坡治理过程中,针对不同河段的不同特点,可选择运用的三种生态护岸治理模式：原生态型治理模式、自然型治理模式和工程生态型治理模式。采用此类护岸方法不仅能满足河道行洪...     

沙颍河生态护岸型式初探

沙颍河的岸坡防护以硬工程为主,但随着社会的发展及与自然和谐观念的加强,其不足之处也逐渐显现出来,迫切需要生态防护措施。在沙颍河流域岸坡防护中,一般采用常规护岸型式,如浆砌石、浆砌混凝土板、模袋等硬工程措施,这些护岸虽能有效地治理护岸险情,但硬工程措施的不足也逐渐显现出来。本文阐述了生态护岸的优势并提出了沙颍河已适用或可以适用的生态防护型式。     

金字塔边坡柔性生态防护技术在河道中的应用

金字塔边坡柔性生态防护技术是一种具有节能、减排、生态、环保、绿化柔性防护为一体的新型边坡防护技术,已成功应用于交通、水利、市政等工程边坡防护中.本文对该技术的金字塔生态袋物理力学特性、边坡防护结构型式、边坡防护稳定性、施工与绿化工艺及要求、经济性等进行了分析总结;分别采用生态袋堆叠加固法及长袋锚固法两种结构型式在中小河道岸坡整治中进行示范应用,应用工程经过2个汛期洪水考验后,经监测分析,在岸坡防护与生态绿化方面皆取得较好效果.该技术在河道岸坡整治中的推广应用对提高河道岸坡生态治理水平、保护河道生态健康具有积极的意义.     

河流冲刷作用下石笼网生态护坡技术研究

与传统护坡相比,生态护坡强调在满足岸坡稳定性的同时达到修复生态、保护环境的目的。概括了河流岸坡生态护坡的内涵和特点,总结了常用于河流岸坡的生态护坡技术,重点介绍了石笼网生态护坡作为一种柔性护坡方式在国内外研究进展及其在工程中的应用。通过对已有理论和试验的分析,阐明了影响石笼网结构护坡性能的主要设计参数。在此基础上,结合工程中出现的问题,提出需要进一步研究的内容:石笼网结构抗冲刷特性研究、石笼网填石料级配、厚度与抗冲流速关系的研究及石笼网与植被的结合试验研究。通过对石笼网结构的深入研究,以获取更多的理论支撑, 进一步优化石笼网结构的设计,更好地指导工程实践。     

加筋式生态绿化挡墙在六安凤凰河综合治理工程中的应用

加筋式生态绿化挡墙安全稳定性高、施工效率高、排水效果好、生态景观效果突出、施工质量易控制和综合造价较低等优点。凤凰河综合治理工程部分河段岸坡防护采用了加筋式生态绿化挡墙,解决了凤凰河河道施工场地狭小、施工工期紧难题,同时满足了水位骤降期岸坡稳定、与上下游岸坡平顺衔接、与周围景观相互协调,达到亲水效果等要求。加筋式生态绿化挡墙作为新型产品,在凤凰河综合治理工程中应用效果较好,在其它中小河流治理中值得借鉴这种岸坡防护形式。     

格宾网垫在牡丹江市铁岭河大桥护岸工程中的应用

格宾网垫护坡结构是一种新型的柔性护坡结构体系,冻胀适应性好,能够适应寒冷地区气候环境条件,且该结构属于多孔隙结构,透水透气性好,便于河水与堤岸间的物质能量交换,维持自然连通性,具有良好的生态景观效应,可以对寒区河流岸坡的生态修复起到应有的作用。     

生态袋挡墙护岸结构设计及其力学性能变化

目前我国河流整治工程中过度硬化现象仍然普遍,亟需开发和应用兼具生态保护、资源可持续利用以及符合工程安全需求的生态护岸技术。生态袋挡墙护岸技术是能够将生态岸坡和墙体工程完美融合的系统,该系统解决了结构工程与生态工程结为一体的难题。以南京市板桥河岸坡整治工程为例,详细研究了生态袋挡墙护岸结构的设计、施工及植被种植技术。通过现场试验段的全过程跟踪,总结归纳出影响生态袋挡墙护岸工程质量的主要因素为生态袋体质量、加筋材料质量、袋内土体密实度、植被覆盖度等。以生态袋这一典型柔性护岸材料为例,通过对比全新生态袋、工程中已使用1.5年的生态袋力学性能和抗老化性能,评估生态袋的耐久性,研究生态岸坡工程质量与生态袋物理力学性能的内在联系,结论表明使用1.5年后的生态袋力学性能保持率较好,但较难满足30年使用寿命的设计要求。必须进一步改进生态袋护岸工程设计和施工方案,以满足工程耐久性能与力学性能要求。     

河流生态型护岸工程的现状研究

传统河流护岸的工程措施采用硬质材料,保持河流岸坡的稳定,在保证结构安全稳定、防止河岸冲刷和水土流失等方面效果显著的同时,也带来了一系列生态影响和不良后果,生态型护岸工程不仅起到了硬质材料的护岸作用,也能保护和恢复河流的生态功能,改善河流景观环境,值得在工程实践中广泛地推广和应用。     

试析生态混凝土护土砖在堤岸整治中的应用

生态混凝土护土砖结构是一种比较理想的生态型堤岸,是在堤岸的岸坡上种植大量植物,将乔木、灌木和草坪相结合,不仅起到美化环境的作用,而且对保持水土具有重要作用,能够维持河道系统生态平衡和河道健康,满足生态和防洪的需求。文章采用两种方案对比的方式,分析了生态混凝土护土砖在江西省三清山管委会枫林镇防洪工程中的应用。     

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。     

Automated system for removal and pneumatic transport of fly ash from electric precipitator hoppers

A system for removal and pneumatic transport of fly ash is examined, in which air pulses act on batches (pistons) of ash formed in a duct. Studies are made of the effect of several physical parameters on the force required to displace a piston of ash and these serve as a basis for choosing a system for removal and pneumatic transport of ash simultaneously from several hoppers of an electric precipitator. This makes it possible to separate the ash particles according to size without introducing additional components. Formulas are given for calculating the structural and dynamic parameters of this system and measurements of indirect dynamic parameters are used to calculate the input-output characteristics of the system. In order to optimize the system, configurations for summing several ducts into a single transport duct for pneumatic ash transport are proposed. Some variants of dry ash utilization and the advantages of producing of size-separated particles are considered. __________ Translated from élektricheskie Stantsii, No. 2, pp. 26–30 (2008).     

The flood pulse advantage and the restoration of river-floodplain systems

The ‘flood pulse advantage’ is the amount by which fish yield per unit mean water area is increased by a natural, predictable flood pulse. Evidence for this increase is presented from tropical and temperate fisheries. It is argued that increasing multispecies fish yield by restoring the natural hydrological regime is consistent with increasing production of other trophic levels and with restoration from ecological and aesthetic viewpoints. When applied to a river-floodplain system, this restoration would provide a large, self-sustaining potential for recreation, commercial exploitation, and flood control. An interim ‘natural flood pulse’ restoration approach is proposed for systems modified for navigation. This approach approximates the natural hydrological regime in a river reach and is intended as a first step in the long process of restoring the watershed.     

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。