计及城市房屋建筑装修破坏的地震经济损失评估方法研究

本文通过对比、分析我国目前地震经济损失评估中存在的一些问题,提出了城市房屋计及装修费用的地震损失评估方法.通过汶川地震现场调查、收集造价资料和问卷调查的形式给出了几个关键参数的合理取值,如:装修破坏损失比、中高档装修重置单价、中高档装修房屋在不同发达水平城市中所占比例及修正系数等.利用本文方法对内蒙古包头西6.4级地震、汶川8.0级地震及深圳经济特区的房屋建筑地震损失进行了评估和预测,并与实际统计结果进行了对比分析,结果表明考虑装修费用损失后的损失评估结果增加了10%～30%.     

Fast assessment of earthquake loss and its application to the 2008 M_S8.0 Wenchuan earthquake

The paper introduces firstly the seismic loss assessment method based on macro-economic indicators and new vulnerability models determined by the data from the on-site damage and loss survey to earthquakes occurred in China during the last two decades.The fast assessment for the 2008 Wenchuan earthquake with MS8.0 is given based on an empirical intensity attenuation relationship.Compared with the assessment based on the practical seismic intensity map of the event according to the on-site investigation, the...     

Lethal toxicity of industrial detergent on bottom dwelling sentinels

We used fresh and brackish water shrimp （Desmoscaris trispinosa and Palaemonetes africanus）, in sediment bioassays to assess the toxicity of an industrial detergent containing high levels of anionic surfactant （linear alkylbenzene sulphonate （LAS））. The Organization for Economic Cooperation and Development （OECD）, # 218 direct sediment toxicity assessment was employed. The organisms were exposed to different concentrations （31.25, 62.5, 125,250 and 500 mg/kg） of the chemical （Neatex） in replicate treatments. Percentage mortality was measured as the ecological endpoint. Mean mortality and estimated lethal concentration LCso values varied with species type, concentration and exposure duration. The statistical variation in the observed mean mortality of the test organisms in the chemical and the control treatment shows that mortality may be induced by the effect of the chemicals. The lethal concentration （LCso） was significantly different at levels ofp 〈 0.05 for the fresh and brackish water experiments. Consequently, assessment of water and sediment quality as a result of chemical pollutants was necessary for protecting some of the more sensitive benthic invertebrates representing the major proportion of the diet of many species in the Niger Delta ecological zone.     

2008年汶川地震造成的应力变化和四川盆地地震危险性增加

2008年5月12日,灾难性的汶川7．9级大地震袭击了青藏高原东缘,造成四川盆地西部多个大城市房屋倒塌和大量人员伤亡。如此大的地震之后,地壳应力的重新调整通常会导致破坏性地震发生（Stein et al,1997;Stein,1999;McCloskey et al,2005;Parsons et al,2000;Parsons,2002）。5月12日地震的主震造成龙门山和四川盆地连接处最大位错量达9m,说明复杂的走滑和逆冲运动（Jiand Hayes,2008）为该地区的特征（Burchfiel et al,1995;Densmore et al,2007）。四川盆地及其周边也有其他活跃的走滑和逆冲断层相互交错。本文利用地震断层模型计算了由2008年5月12日汶川地震引起的同震应力变化,结果显示很多地区应力显著增加。快速给出这种应力变化图像有助于确定未来可能发生强余震的断层段。     

附加黏滞阻尼器结构简化分析方法

介绍了FEMA273给出的传统结构线性静力分析方法,并用该法分析附加粘滞流体阻尼器结构,给出了附加粘滞流体阻尼器结构抗震性能评估的具体分析方法.为了验证所提方法的精确性,对设计好的附加黏滞阻尼器结构进行了非线性动力分析,动力分析使用的人工波加速度反应谱形状与设计消能结构时使用的设计反应谱相匹配.实例分析结果表明,该方法能快速、有效地评估附加流体阻尼器结构在大震作用下的抗震性能,特别是在消能结构初步设计和分析阶段.     

Performance-based concept on seismic evaluation of existing bridges

Conventional seismic evaluation of existing bridges explores the ability of a bridge to survive under significant earthquake excitations. This approach has several major drawbacks, such as only a single structural performance of near collapse is considered, and the simplified approach of adopting strength-based concept to indirectly estimate the nonlinear behavior of a structure lacks accuracy. As a result, performance-based concepts that include a wider variety of structural performance states of a given bridge excited by different levels of earthquake intensity is needed by the engineering community. This paper introduces an improved process for the seismic evaluation of existing bridges. The relationship between the overall structural performance and earthquakes with varying levels of peak ground acceleration (PGA) can successfully be linked. A universal perspective on the seismic evaluation of bridges over their entire life-cycle can be easily obtained to investigate multiple performance objectives. The accuracy of the proposed method, based on pushover analysis, is proven in a case study that compares the results from the proposed procedure with additional nonlinear time history analyses.     

A new framework for evaluating along-wind responses of a transmission tower

In this paper, an analytical framework to evaluate the along-wind-induced dynamic responses of a transmission tower is presented. Two analytical models and a new method are developed: (1) a higher mode generalized force spectrum (GFS) model of the transmission tower is deduced; (2) an analytical model that includes the contributions of the higher modes is further derived as a rational algebraic formula to estimate the structural displacement response; and (3) a new approach, applying load with displacement (ALD) instead of force, to solve the internal force of transmission tower is given. Unlike conventional methods, the ALD method can avoid calculating equivalent static wind loads (ESWLs). Finally, a transmission tower structure is used as a numerical example to verify the feasibility and accuracy of the ALD method.     

变参数DCD算法在岩土工程位移反分析中的应用

常规DCD(dynamic canonical descent)算法具有全局优化能力且无需考虑目标函数的可微性,只要预先定义优化空间即可,但是该算法的收敛速度有限,为此提出了变参数DCD算法,并建立了其相应的算法迭代格式。在数值试验和工程应用中将该变参数DCD算法与常规的DCD算法进行比较,其结果均表明：变参数DCD算法在全局优化能力和收敛速度上找到了一个均衡点,该算法不仅具有DCD算法的全局优化能力,而且收敛时所需的目标函数评估次数少,在优化过程中该算法展示出了稳定性强且优化结果可靠度高的一面。     

滑坡次生灾害损失评估方法研究

针对目前滑坡灾害破坏损失评估研究还没有涉及滑坡次生灾害破坏损失评估方面的研究,提出并建立了滑坡次生灾害破坏损失的评估模型与方法。应用故障树分析法（FTA）和事件树分析法（ETA）相结合的因果图方法对滑坡次生灾害作可靠性分析,由此对滑坡次生灾害损失进行了预测及评估。     

营口市滨海大道地质灾害危险性综合评估与防治措施

营口市滨海大道工程属于重要项目,建设用地所处地质环境为中等—复杂区,现状地质灾害主要类型为崩塌灾害。通过对危险性起决定作用的地形条件、地层岩性、构造地震、人类活动4方面因素的分析,该地区地质灾害危险性分级属危险性小级,地质灾害危险性分区属于危险性小区,因而在采取措施条件下适宜路桥建设,并提出了防治措施,为施工建设打下了基础。