碳纤维布补强加固钢筋混凝土板的研究与工程应用

通过碳纤维布补强加固钢筋混凝土板的试验，研究了碳纤维布对钢筋混凝土板受弯性能的影响，试验研究表明，使用碳纤维布提高钢筋混凝土受弯构件正截面承载力的方法是有效，试验板的受弯性能明显改善，基于有关的理论分析，探讨了碳纤维布补强加固钢筋混凝土板受弯承载力的设计方法，并在此基础上应用碳纤维布对某实际工程中的钢筋混凝土土板实施了补强加固。     

钢筋混凝土双筋梁的力学特性和应用

关于钢筋混凝土双筋梁，历不普遍被认为是不经济的，不宜普遍采用。本文通过对钢筋混凝土双筋梁的承载力和延性及变形性能的分析，提出钢筋混凝土双筋梁可以普遍应用的新观点。     

浏河口土工合成织物加筋土护岸工程

位于长江河口段的浏河口河岸因受潮汐、风浪、船行波的侵蚀和冲刷、河岸严重坍塌，已成险工，急需修建护岸工程。工程中使用了高分子聚脂合成纤维修建加筋土挡墙，并在加筋体表面护砌混凝土预制块。由于土工合成筋材和土体界面剪向应力的效应，使其土体所受剪力转化为筋材的拉力，充分发挥了筋材强度高的特性，限制了土体的侧向变形，保证了岸线的内部稳定。使用钢筋混凝土锚定板护面，既可防止土工合成织物的老化，又可保护河岸免受     

双向预应力混凝土板抗弯剪性能的非线性有限元分析

本文在非线性有限元分析理论的基础上，设计了可用于普通钢筋混凝土板和双向预应力混凝土板的计算机程序，程序中引入了ｏｔｔｏｓｓｅｎ４参数模型，考虑了板中Ｚ向剪应力对板单元破坏的影响，使程序能较好的反映高配筋率板的抗剪性能，做到变剪计算的统一。     

钢筋混凝土板的试验与非线性计算分析

本文介绍钢筋混凝土板条梁和钢筋混凝土板的静力性能试验。根据板混凝土和钢筋的实测应变,推算跨中截面沿板跨中心线方向的弯矩分布场。用板条梁各阶段的实测弯曲刚度,视板的裂缝方向作适当的折减,并考虑泊松比影响,对两对边简支、两对边自由的钢筋混凝土板,其中点承受局部均布荷载时进行有限元全过程分析。计算结果与试验结果符合较好。     

韩庄闸公路桥结构试验及承载力评估

本文介绍韩庄闸公路桥桥面结构现场试验及试验结果，结合有发棱柱条件计算，分析了由钢筋混凝土空心板和Ｔ梁组成的桥面结构之受力变形特征，根据试验结果及计算分析，确定了该公路桥的荷载横向分布系数和动力系数，据此评估了公路桥桥面结构的实际承载力。     

韩庄闸公路桥结构试验及承载力评估

本文介绍韩庄闸公路桥桥面结构现场试验及试验结果，结合有限棱柱条件计算，分析了由钢筋混凝土空心板和T梁组成的桥面结构之受力变形特征。根据试验结果及计算分析，确定了该公路桥的荷载横向分布系数和动力系数，据此评估了公路桥桥面结构的实际承载力。     

装配式桁架钢筋混凝土叠合板-圆孔蜂窝组合扁梁力学试验研究

针对目前装配式钢结构住宅施工焊接量大，防火防腐处理复杂等问题，为了提高施工效率，将桁架钢筋混凝土叠合板与圆孔蜂窝钢梁进行组合，形成装配式桁架钢筋混凝土叠合板－圆孔蜂窝组合扁梁。通过两组组合扁梁试件的力学试验，对其承载能力、变形能力、破坏规律等方面进行分析和研究。结果表明:组合扁梁的破坏经历了三个阶段即弹性阶段、弹塑性阶段和塑性阶段；蜂窝钢梁沿截面高度方向上的应变直线分布；组合扁梁屈服时，弯矩试验值比公式计算值提高了２０％ ～６０％，剪力试验值约为公式计算值的０．８倍；考虑组合扁梁翼缘板影响的挠度折减系数α 为０．５。由于叠合板的约束作用，组合扁梁在整个加载过程中没有出现局部变形、平面外失稳及现浇层与叠合层之间的脱离和滑移现象，有较好的整体性和变形能力。     

U型钢筋混凝土板桩在河道整治中的应用

为了进一步了解U型钢筋混凝土板桩在工程实践中的使用情况,本文对采用U型钢筋混凝土板桩的工程实例——无锡市钱桥洋溪河南岸综合整治工程进行了简要的介绍。在前人研究成果的基础上,着重阐述了U型钢筋混凝土板桩的特点,结合工程实例比较分析了U型钢筋混凝土板桩和普通钢筋混凝土挡墙两种岸墙形式的优缺点,并对U型钢筋混凝土板桩堤防进行稳定分析,同时总结了U型钢筋混凝土板桩在施工过程中的注意事项,为其他相似工程提供一定的参考与借鉴。     

某钢筋混凝土盖板现场荷载试验及性能评价

为检测新修钢筋混凝土盖板的工作性能，进行了现场荷载试验，由此得到了盖板在最大允许荷载作用下产生的短期挠度、开裂情况及残余变形，并对各项性能进行了评价，为盖板的后期使用提供了依据．     

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…