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1.
现有的生命线抗震可靠性分析多采用两元易损性假设,即假设单元和系统的工作状态仅有“连通”与“断开”两种,并以连通可靠度近似代替系统抗震可靠性。事实上,系统或单元的工作状态从“连通”与“断开”是渐变的,或者说从连通到不连通之间具有中介状态,通过建立生命线工程的震后工作状态判别准则,定义了“连通-中介-断开”三维可靠性向量。并在传统“连通—断开”模式下的网络系统可靠性评估方法的基础上,提出具有中介状态的生命线网络工程系统抗震可靠性评估方法。  相似文献   

2.
张桂欣  孙柏涛  陈相兆 《地震》2017,37(4):69-79
生命线工程的震害及损失评估工作对于震害防御和震后地震应急工作有着极其重要的意义。 但是, 生命线工程是一个复杂庞大的网络系统, 目前对其开展的震害及损失评估研究工作存在着很大的局限性和不确定性。 本文充分利用研究较多且较系统的建筑物震害及损失评估结果, 结合历次典型历史地震震害中建筑物和生命线震害情况, 通过分析建筑物损失和生命线工程损失的数量关系, 建立二者之间的关联模型; 通过对人口、 GDP、 土地利用等公里网格数据进行分析, 给出中国大陆地区的分区分类原则, 建立分区分类的生命线工程地震直接经济损失分析模型; 基于GIS软件平台, 开发了生命线工程地震直接经济损失分析模块, 利用该模块, 得出了四川省不同地震烈度下的生命线工程直接经济损失空间分布情况。  相似文献   

3.
生命线系统在城市防震减灾和震后功能恢复中起着至关重要的作用,生命线系统的抗震能力是影响城市防震减灾能力标定的重要部分。本文在已有的研究成果和震害经验的基础上,建立了生命线系统影响城市防震减灾能力标定的指标体系,并根据其在地震中的破坏特点,确定了最终的指标权重;然后参考生命线系统的评价标准,提出了生命线系统对地震灾害损失的影响评价方法。  相似文献   

4.
以横向有接头地下综合管廊非一致激励振动台试验为基础,基于有限元软件ABAQUS,建立了土-地下综合管廊结构数值模型,采用非线性弹簧单元模拟地下综合管廊的接头。分析了模型箱的边界效应、加速度响应、位移响应、以及管廊接头响应,有限元计算结果与试验实测结果进行对比分析,二者对比结果呈一致趋势,非线性弹簧单元可为生命线工程结构接头数值模拟提供了新思路。  相似文献   

5.
对于生命线工程网络系统而言,合理分析和评估其带有网络特征的节点可靠度,比只研究单体可靠度更具实际意义。基于数据包络分析法(Data Envelopment Analysis,DEA)有效性分析的思想,提出了生命线网络节点抗灾相对可靠度的概念。从生命线工程在灾害环境下着重体现出的系统性和网络性出发,考察网络中的节点所能实现的资源供给功能与其所在网络中的空间结构重要性是否匹配,即功能性相对于结构性的可靠度。选择节点资源实际需求量和管内水压作为DEA有效性分析的输入参数,结构重要性作为输出参数,并用网络中介中心性评价结构重要性,获得相应参数。通过实例分析,得出实例工程网络中各节点相应的DEA有效性分析结果,即相对可靠度,并通过对参数的权系数调整,得到了使非有效单元变为有效单元的调整值。该调整值可供优化及改进工程网络的技术性调整方案参考,相对可靠度也可作为评价工程网络系统性能的有益补充。  相似文献   

6.
底层大空间带暗支撑剪力墙结构非线性地震反应分析   总被引:4,自引:0,他引:4  
利用在剪力墙多垂直杆非线性单元模型中增设支撑斜杆的方法,来分析带暗支撑剪力墙结构的非线性地震反应,给出了带支撑斜杆的多垂直杆剪力墙单元模型的刚度矩阵和各元件的本构关系。最后提供了算例,并与试验结果比较,表明带支撑斜杆的多垂直杆剪力墙非线性单元模型具有较好的计算精度。  相似文献   

7.
生命线地震工程中的几个基本问题   总被引:2,自引:0,他引:2  
本文提出了生命线工程系统的抗震设计准则,对生命线工程系统的可靠性进行了讨论,给出了一种地下管网系统可靠性分析的方法。文中提出了一种生命线工程系统受灾程度的定量分析方法。最后还建立了一个计算生命线工程系统直接经济损失和第一次间接经济损失的分析模型。  相似文献   

8.
基于三维粘弹性人工边界理论,推导建立了类似于普通有限单元而具有粘弹性人工边界特性的三维紧支粘弹性边界单元,并结合UPFs二次开发的特点成功嵌入通用有限元软件ANSYS中。通过Lamb表面源问题和内源问题算例,对上述建立的单元进行了验证,计算结果表明,该单元具有与等效弹簧-阻尼器单元相同的精度和稳定性,并且使用更为简便,可操作性更强,同时基于ANSYS强大的开发平台和非线性计算能力,尚可开展其他特殊用途单元的二次开发。  相似文献   

9.
以道路网格作为计算单元进行震害分析,比采用传统的行政区、街道办、社区或公里网格具有较大优势,并更接近实际。道路网格是以道路中心线为基础,并结合其它如生命线系统中的地下管网而形成的多边形实体,包括线要素层和面要素层。道路网格在GIS中通常用于最短路径分析、最优路径分析、缓冲区分析和叠置分析;在震害分析中可应用于居住人数统计、高危害小区分析、网络(建立在供水、供气等管网基础上的)功能失效分析和灾害救助分析等。  相似文献   

10.
本文回顾了国内外生命线地震工程领域近10年来的研究进展。通过统计中英文期刊上的论文发表数量,分析了生命线地震工程各研究方向的发展动态。总结了埋地管道和隧道与地下结构两个方面的研究进展,并重点梳理了埋地管线抗震研究中大型试验、精细化模拟和理论方法3个方面的研究成果。最后,结合第16届世界地震工程大会(16WCEE)上发表的最新研究成果,对未来生命线地震工程研究的发展进行了分析与展望。  相似文献   

11.
青新交界8.1级地震生命线工程震害   总被引:10,自引:5,他引:10  
介绍了青新交界8.1级地震中青藏公路沿线各类生命线工程的震害,初步分析了产生震害的原因。  相似文献   

12.
Lifelines earthquake vulnerability assessment: a systemic approach   总被引:4,自引:0,他引:4  
This study aimed at developing a model to evaluate lifelines seismic vulnerability, considering physical, functional, and organizational factors as deeply interconnected one to the other. The resulting assessment tool consists of a set of parameters measuring the response capacity of lifelines exposed to earthquakes.

The notion of systemic vulnerability is the underlying frame of the proposed evaluation method: what can be measured is how prone is a system to damage or failure not only as a consequence of some kind of physical damage occurring to one of its components, but also as the indirect effect of some physical, functional, or organizational failure suffered by other systems.

The assessment tool has been applied in Regione Lombardia, Italy, providing as a final output recommendations for prioritizing and taking actions to reduce the potential of magnified effects as a consequence of lifelines interruption in earthquakes aftermath.  相似文献   


13.
Some lifelines, such as gas and oil transmission lines and water and sewer pipelines, have been damaged in recent earthquakes. The damages of these lifelines may cause major, catastrophic disruption of essential services for human needs. Large abrupt differential ground movements that result from an active fault present one of the most severe effects of an earthquake on a buried pipeline system. Although simplified analysis procedures for buried pipelines across strike-slip fault zones that cause tensile failure of the pipeline have been proposed, the results are not accurate enough because of several assumptions involved, such as the omission of flexural rigidity of the pipe, simplification of soil resistant characteristics, etc. Note that the omission of flexural rigidity cannot satisfy equilibrium conditions for pipelines across a ‘reverse’ strike-slip fault that causes compressions in the pipeline. This paper presents a refined analysis procedure for buried pipelines that is applicable to both strike-slip and reverse strikeslip faults after modifying some of the assumptions used previously. Based on the analytical results, this paper also discusses the design criteria for buried pipelines which are subjected to various fault movements. Parametric responses of buried pipeline for various fault movements, angles of crossing, buried depths and pipe diameters are presented.  相似文献   

14.
Through natural partition and clustering analysis, four kinds of flow units were distinguished in Pu53 block, Pucheng Oilfield. Taking the short-term cycle as studying unit, the two-dimensional distribution of each type of flow units was forecasted and the short-term cycle was classified into four types based on the two-dimensional characteristics of the flow units. The remaining oil was predicted by conceptual simulation, qualitative analysis and quantitative modeling. The results showed obvious control of the characteristics of reservoir flow units to the remaining oil. E and G units in type I and type II short-term cycles which are distributed continuously in large areas are mostly flooded, while the uncontrolled small isolated G flow unit in type III short-term cycles which were mainly made of F flow unit and F flow unit with continuous distribution become the accumulating place for remaining oil. Thus the development adjustment strategy should optimize the development of small-scale E and G units, strengthen the development of type III short-term cycles, and block out type I short-term cycles. This strategy improves the development of Pu53 block obviously.  相似文献   

15.

Through natural partition and clustering analysis, four kinds of flow units were distinguished in Pu53 block, Pucheng Oilfield. Taking the short-term cycle as studying unit, the two-dimensional distribution of each type of flow units was forecasted and the short-term cycle was classified into four types based on the two-dimensional characteristics of the flow units. The remaining oil was predicted by conceptual simulation, qualitative analysis and quantitative modeling. The results showed obvious control of the characteristics of reservoir flow units to the remaining oil. E and G units in type I and type II short-term cycles which are distributed continuously in large areas are mostly flooded, while the uncontrolled small isolated G flow unit in type III short-term cycles which were mainly made of F flow unit and F flow unit with continuous distribution become the accumulating place for remaining oil. Thus the development adjustment strategy should optimize the development of small-scale E and G units, strengthen the development of type III short-term cycles, and block out type I short-term cycles. This strategy improves the development of Pu53 block obviously.

  相似文献   

16.
Probabilistic seismic risk assessment for spatially distributed lifelines is less straightforward than for individual structures. While procedures such as the ‘PEER framework’ have been developed for risk assessment of individual structures, these are not easily applicable to distributed lifeline systems, due to difficulties in describing ground‐motion intensity (e.g. spectral acceleration) over a region (in contrast to ground‐motion intensity at a single site, which is easily quantified using Probabilistic Seismic Hazard Analysis), and since the link between the ground‐motion intensities and lifeline performance is usually not available in closed form. As a result, Monte Carlo simulation (MCS) and its variants are well suited for characterizing ground motions and computing resulting losses to lifelines. This paper proposes a simulation‐based framework for developing a small but stochastically representative catalog of earthquake ground‐motion intensity maps that can be used for lifeline risk assessment. In this framework, Importance Sampling is used to preferentially sample ‘important’ ground‐motion intensity maps, and K‐Means Clustering is used to identify and combine redundant maps in order to obtain a small catalog. The effects of sampling and clustering are accounted for through a weighting on each remaining map, so that the resulting catalog is still a probabilistically correct representation. The feasibility of the proposed simulation framework is illustrated by using it to assess the seismic risk of a simplified model of the San Francisco Bay Area transportation network. A catalog of just 150 intensity maps is generated to represent hazard at 1038 sites from 10 regional fault segments causing earthquakes with magnitudes between five and eight. The risk estimates obtained using these maps are consistent with those obtained using conventional MCS utilizing many orders of magnitudes more ground‐motion intensity maps. Therefore, the proposed technique can be used to drastically reduce the computational expense of a simulation‐based risk assessment, without compromising the accuracy of the risk estimates. This will facilitate computationally intensive risk analysis of systems such as transportation networks. Finally, the study shows that the uncertainties in the ground‐motion intensities and the spatial correlations between ground‐motion intensities at various sites must be modeled in order to obtain unbiased estimates of lifeline risk. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

17.
基于构造的测震学参数在鲁东-黄海地块的应用   总被引:1,自引:1,他引:0  
以基于构造的测震学参数分析为思路,利用地震构造分区和地质构造单元的划分结果,检验了基于活动边界带的测震学参数方法的可行性;将活动地块内部(地质构造复杂且地震活动频繁)构造单元与测震学参数相结合,研究中强震前震源区所在的构造单元测震学参数的变化特征,提取具有中期预测意义的震兆标志,为中强震的预测提供理论依据。结果显示:中强地震前,郯庐断裂带(鲁东-黄海地块西边界带)及扬子地块(鲁东-黄海地块内部构造单元)D、C值异常过程明显,且各有特点,证明了基于活动地块内部构造单元的测震学参数方法具有良好的可行性。  相似文献   

18.
A procedure for seismic risk assessment is applied to the Mt. Etna area (eastern Sicily, Italy) through assessment of urban system dysfunction following the occurrence of an earthquake. The tool used is based on the Disruption Index as a concept implemented in Simulator QuakeIST, which defines urban disruption following a natural disaster. The first element of the procedure is the definition of the seismic input, which is based on information about historical seismicity and seismogenic faults. The second element is computation of seismic impact on the building stock and infrastructure in the area considered. Information on urban-scale vulnerability was collected and a geographic information system was used to organise the data relating to buildings and network systems (e.g., building stock, schools, strategic structures, lifelines). The central idea underlying the definition of the Disruption Index is identification and evaluation of the impact on a target community through the physical elements that most contribute to severe disruption. The procedure applied in this study (i.e., software and data) constitutes a very useful operational tool to drive the development of strategies to minimise risks from earthquakes.  相似文献   

19.
This paper evaluates different characteristics for earthquake early warning.The scaling relationships between magnitude,epicenter distance and calculated parameters are derived from earthquake event data from USGS.The standard STA/LTA method is modified by adding two new parameters to eliminate the effects of the spike-type noise and small pulsetype noise ahead of the onset of the P-wave.After the detection of the P-wave,the algorithm extracts 12 kinds of parameters from the first 3 seconds of the P-wave.Then stepwise regression analysis of these parameters is performed to estimate the epicentral distance and magnitude.Six different parameters are selected to estimate the epicentral distance,and the median error for all 419 estimates is 16.5 km.Four parameters are optimally combined to estimate the magnitude,and the mean error for all events is 0.0 magnitude units,with a standard deviation of 0.5.Finally,based on the estimation results,additional work is proposed to improve the accuracy of the results.  相似文献   

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