Earthquake safety assessment of concrete arch and gravity dams

Based on research studies currently being carried out at Dalian University of Technology, some important aspects for the earthquake safety assessment of concrete dams are reviewed and discussed. First, the rate-dependent behavior of concrete subjected to earthquake loading is examined, emphasizing the properties of concrete under cyclic and biaxial loading conditions. Second, a modified four-parameter Hsieh-Ting-Chen viscoplastic consistency model is developed to simulate the rate-dependent behavior of concrete. The earthquake response of a 278m high arch dam is analyzed, and the results show that the strain-rate effects become noticeable in the inelastic range. Third, a more accurate non-smooth Newton algorithm for the solution of three-dimensional frictional contact problems is developed to study the joint opening effects of arch dams during strong earthquakes. Such effects on two nearly 300m high arch dams have been studied. It was found that the canyon shape has great influence on the magnitude and distribution of the joint opening along the dam axis. Fourth, the scaled boundary finite element method presented by Song and Wolf is employed to study the dam-reservoir-foundation interaction effects of concrete dams. Particular emphases were placed on the variation of foundation stiffness and the anisotropic behavior of the foundation material on the dynamic response of concrete dams. Finally, nonlinear modeling of concrete to study the damage evolution of concrete dams during strong earthquakes is discussed. An elastic-damage mechanics approach for damage prediction of concrete gravity dams is described as an example. These findings are helpful in understanding the dynamic behavior of concrete dams and promoting the improvement of seismic safety assessment methods.     

高桩码头锈蚀破损面板残余承载力评估方法

高桩码头长期工作在具有腐蚀介质的潮湿环境中，因钢筋的锈蚀会使构件表面砼胀裂而破损，目前我国大部分的高桩码头进入了锈蚀破损的高峰期。通过研究指出：以往国内外用构件蚀破损表面积大小或顺筋裂缝大小的标准来确定维修方案的方法是不正确的。根据一般构件为等截面，而沿跨度分布的弯矩不均匀的事实，指出构件在控制断面以外的部位强度有富裕，允许钢筋适当的锈蚀仍能满足设计强度的新见解。提出了锈蚀破损面板的强度安全性评估准则、强度因子新概念及其具体计算式，可以量化评估犭蚀破损面板的残余承载力，为科学制定锈蚀破损面板的维修方案提供参考，在保证码头结构安全的同时，大大节省维修费用。     

几种食用贝类淀粉酶活性的初步研究

本研究对10种常见食用贝类成体的淀粉酶在不同pH值、不同温度条件下进行了活性测定。结果表明,其总体消化器官淀粉酶的最适温度为:青蛤(Cyclina sinensis),33℃;缢蛏（Sinonovacula constricta),32℃;文蛤(Meretrix meretrix),43℃;等边浅蛤(Gomphina veneriformis),35℃;菲律宾蛤仔(Ruditapes philippinarum),34℃;泥螺(Bullacta exarata),40℃;彩虹明樱蛤(Moerella iridescens),37℃;微黄镰玉螺(Lunatica gilva),43℃;锈凹螺(Chlorostoma rusticum),43℃;疣荔枝螺(Thais clavigera),43℃;淀粉酶的最适pH值范围为4.6-4,9,不同贝类稍有不同;同一种类中肝脏淀粉酶的活性大于肠淀粉酶的活性。     

日本蟳人工育苗技术的初步研究

The paper is related to the results of preliminary studies of artificial rearing of juvenile Charybdis (charybdis) japonica. The results have proved that it is possible to use seedling production installation of other aquatic animals for seedling of Charybdis (charybdis) japonica. And therefore, the increase of marine resource, such as the crab, will also be made possible. The experiment also provided information on crabs’ fishing, transporting, stocking, spawning, hatching, and larvaes rearing techniques. The increase of the survival rate of larvaes, however, need further be studied.     

电子影像地图的技术研究

本文概述了电子影像地图的概念及其与地理信息系统的关系,详细介绍了电子影像地图的技术和实现方法.在上述理论基础上,本文研制了上海市电子影像地图,在研制过程中解决了数据安全性的问题、大数据量的存储、传送问题等等.论文依据面向对象的设计原理和编程方法,用Visual C 开发了用户的浏览查询界面,为普通用户提供了一个快速的查询浏览平台.     

蛇模型在等深线自动化简中的应用

针对当前等深线的化简主要依靠经验和手工方法实施,其自动化简仍未取得实质性突破的现状。从等深线化简的安全性约束出发,阐释了蛇模型的基本内涵,分析和计算了蛇模型曲线所受的力,明确了蛇模型点的安全约束方法,推导了蛇模型的能量公式,并实现了基于蛇模型的等深线自动化简。试验结果表明,采用该算法化简后的等深线能够很好地遵守安全性约束准则;蛇模型算法可以用来实现等深线的自动化简。     

江苏垃圾填埋场生态地质环境安全性评价及工程治理

以生态地质环境系统安全为理论框架,以综合指数法和层次分析法为技术支点,构建了垃圾填埋场生态地质环境模型和生态地质环境风险等级的判别方法.选择了南京轿子山生活垃圾填埋场为典型实例,评价该场生态环境安全总体堪忧,且达到Ⅰ级红色预警状态.从地质分析入手,结合应用工程施工技术方法,参照相关规范,对填埋场进行污染治理方案设计.     

地震安全性评价中若干地震地质问题探讨

本文在对活动断层的工程涵义进行了简要分析后,讨论了断层物质测年的工程应用进展及其断层活动时代鉴定问题,并就如何加强中强地震发震构造判别、应用地震地质资料评估大地震年平均发生率、以及活动断层地表断错位移的概率评价等问题作了初步探讨。     

地震统计区地震活动性参数b值及ν_4不确定性研究

根据《地震安全性评价工程师制度暂行规定》和《地震安全性评价工程师资格考试实施办法》,为了做好全国注册地震安全性评价工程师执业资格考试工作,中国地震局组织编制了《一级地震安全性评价工程师资格考试大纲》和《二级地震安全性评价工程师资格考试大纲》,现已经人事部组织审定通过,并予以印发公布。     

工程场地地震安全性评价工作及相关技术问题

本文简单回顾了工程场地地震安全性评价工作的变迁与发展过程,探讨了几个关键的技术问题,分析了相关技术方法的发展与更新趋势。文中重点讨论了不同的地震影响量之间概率水平的一致性问题,同时对在设防水准的选取、地震危险性分析中的不确定性考虑、地震动衰减笑系的获取、地震动时程合成中的参数匹配、场地地震反应分析中的非线性处理、设计地震动确定等方面遇到的一些技术问题进行了分析,并且给出了对这些问题处理的一些看法和建议。