既有钢管混凝土拱桥桥动力测试和有限元分析

桥梁结构的动力特性(振型、频率和阻尼)是桥梁承载能力评定的重要参数,同时也是识别桥梁结构工作性能和桥梁抗震分析的重要参数。     

地质雷达在防渗墙检测中的应用

水库堤坝中的防渗墙属于隐蔽型的重要水利工程,坝体的结构层形态复杂多变,探测难度大,为确保水库堤坝安全可靠地运行,采用高分辨率的物探方法对其探测是必需的.基于地质雷达检测技术,以某水库堤坝检测为实例,通过RADPR0软件对地质雷达资料进行处理,并对该雷达图像做出合理的地质解释,从而查明墙体内可能存在的不连续地段,以便及时...     

大坝混凝土材料溶蚀性试验研究

采用新安江库水浸泡坝址混凝土新、老龄期岩样的方法进行水—混凝土材料的溶蚀试验,主要通过测pH值、TDS（Total Dissolved Solids）、电导率这三个有代表性的指标,来评价混凝土岩样在浸泡过程中的溶蚀情况。     

The effect of the infill in arched structures: Analytical and numerical modelling

Although arches, vaults and domes were essential structural elements in ancient engineering works, their structural analysis presents a challenge to modern designers. It was well known by the medieval builders that infill is essential for the stability of arched structures. Nevertheless, some disasters occur nowadays due to incorrect infill removal, usually done with the purpose of decreasing the applied load. In the present work a comprehensive analysis of the infill influence on the structural behaviour of arched structures is performed. For this purpose analytical models based on equilibrium considerations and finite elements models are used. Experimental results obtained from the Bargower bridge destructive test, are used to calibrate the numerical results. Some conclusions regarding the structural behaviour of arched structures and modelling strategies are presented.     

汶川地震余震记录及紫坪铺面板堆石坝余震反应研究

对汶川地震后紫坪铺面板堆石坝台阵余震记录进行了分析,研究实测余震地震动频谱特性等基本特征。选择有代表性的坝址基岩台站记录到的余震地震动作为大坝地震动输入,对紫坪铺大坝进行了三维动力有限元分析,并将计算得到的坝体加速度放大倍数与不同坝高台站的监测数据进行了对比。研究结果表明：实测余震地震动加速度反应谱在短周期部分有一定波动,在周期稍长时随周期增加而衰减,符合地震动反应谱的基本特征;综合实测大坝反应、数值计算结果以及以往实测相关资料,本次紫坪铺大坝余震实测结果反映了土工构筑物反应的一般规律。     

包钢尾矿坝及周边土壤重金属复合污染特征

应用综合污染评价法和Hakanson潜在生态风险指数法对包钢尾矿坝及周边的表层土壤中（0~20 cm）重金属元素铅、锌、铜、砷和铬单独与复合污染特征进行研究,定量测定了包钢尾矿坝的潜在生态风险程度、主要污染因子和潜在生态风险因子。结果表明：包钢尾矿坝及周边土壤受到不同程度的重金属污染,各重金属潜在生态风险参数由高至低顺序为Pb＞As＞Cu＞Cr＞Zn,Pb的潜在污染风险参数最高,是主要潜在生态风险因子,其次是As。     

曹娥江袍江大桥初应力研究

对于主拱肋为桁式截面的钢管混凝土拱桥。其拱肋由多根弦管组成,浇筑时间和浇筑顺序的不同对初应力度有一定的影响,因此,以曹娥江袍江大桥为工程背景,建立有限元模型,模拟了钢管混凝土拱桥的不同浇筑顺序和浇筑时问对拱肋初应力的影响,并在此基础上进行了考虑初应力的曹娥江袍江大桥的极限承载力计算。     

21世纪中国水坝安全管理、退役与建设的若干问题

从中国水库大坝建设的基本情况入手,分析了21世纪中国水库大坝建设管理中的若干问题,重点阐述了在水库大坝安全管理中的降等与报废制度,以及病险水库大坝的除险加固.同时,依据有关法规,提出了水库大坝建设与运用要符合流域综合规划的要求,注重生态环境的保护,以及与生态友好的水利水电工程技术等.倡导了人与自然和谐,建设绿色水工程,建立对各种资源可持续利用的良性循环机制.     

百色水利枢纽溢流坝掺气减蚀研究

百色水利枢纽工程RCC主坝高130m，最大水头差102m，溢流坝最大单宽流量约166m^3／S，流速超过40m／s，采用宽尾墩加消力池联合消能，由于水头高，流速大，堰面气蚀问题突出，水流掺气是减灭气蚀的有效方法，通过分析其它工程掺气减蚀的经验，就百色水利枢纽大比例尺模型试验来研究百色掺气水流的特性，掺气减蚀效果的评估以及掺气坎的最佳布置。     

Beaver herbivory and its effect on cottonwood trees: influence of flooding along matched regulated and unregulated rivers

We compared beaver (Castor canadensis) foraging patterns on Fremont cottonwood (Populus deltoides subsp. wislizenii) saplings and the probability of saplings being cut on a 10 km reach of the flow‐regulated Green River and a 8.6 km reach of the free‐flowing Yampa River in northwestern Colorado. We measured the abundance and density of cottonwood on each reach and followed the fates of individually marked saplings in three patches of cottonwood on the Yampa River and two patches on the Green River. Two natural floods on the Yampa River and one controlled flood on the Green River between May 1998 and November 1999 allowed us to assess the effect of flooding on beaver herbivory. Independent of beaver herbivory, flow regulation on the Green River has caused a decrease in number of cottonwood patches per kilometre of river, area of patches per kilometre, and average stem density within cottonwood patches. The number of saplings cut per beaver colony was three times lower on the Green River than on the Yampa River but the probability of a sapling being cut by a beaver was still higher on the Green River because of lower sapling density there. Controlled flooding appeared to increase the rate of foraging on the Green River by inundating patches of cottonwood, which enhanced access by beaver. Our results suggest regulation can magnify the impact of beaver on cottonwood through interrelated effects on plant spatial distribution and cottonwood density, with the result that beaver herbivory will need to be considered in plans to enhance cottonwood populations along regulated rivers. Published in 2002 by John Wiley & Sons, Ltd.