共查询到19条相似文献,搜索用时 468 毫秒
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震后城市交通系统评估与改建 总被引:7,自引:0,他引:7
通过对城市交通系统震害预测方法的研究及实例分析,提出了道路富裕宽度及标准长度的概念,制定了根据路长修正城市道路砾阻塞量界限值的方案,计算结果表明,要害部位的选址对其功能的发挥影响巨大。按照本文方法改进相应的路段,城市交通系统可以基本达到高烈度地下震后逑为的要求。 相似文献
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多点地震激励下基于改进振型位移法的反应谱方法 总被引:1,自引:0,他引:1
基于平稳随机振动理论,运用改进的振型位移法,得到结构多点输入改进的反应谱法,对其中相关系数进行了计算和讨论,对相关系数解析解进行了讨论,得到了解析公式的适用范围。最后通过算例进行了本文方法与MSRS方法计算结果比较,说明本文方法推导是正确的,收敛速度高于MSRS方法。 相似文献
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结构-地基相互作用体系动力特性参数的简化计算方法 总被引:2,自引:1,他引:2
本文首先介绍了几种计算结构-地基相互作用体系动力特性的简化方法,并用振动台模型试验的数据资料进行计算分析,讨论了各方法的局限性;在此基础上,提出了一种改进的简化计算方法。在该方法中,主要改进是合理考虑了桩基对体系刚度的贡献。 相似文献
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根据倾斜固体潮波记录曲线的特性及多年工作的经验,对现行观测中,调仪器时间较长或停记时间较长情况下进行校正值的计算提出了一种改进方法,该方法能较好地提高校正值计算的精度,使校正值更为合理。 相似文献
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The problem of updating a structural model and its associated uncertainties by utilizing structural response data is addressed. In an identifiable case, the posterior probability density function (PDF) of the uncertain model parameters for given measured data can be approximated by a weighted sum of Gaussian distributions centered at a number of discrete optimal values of the parameters at which some positive measure‐of‐fit function is minimized. The present paper focuses on the problem of model updating in the general unidentifiable case for which certain simplifying assumptions available for identifiable cases are not valid. In this case, the PDF is distributed in the neighbourhood of an extended and usually highly complex manifold of the parameter space that cannot be calculated explicitly. The computational difficulties associated with calculating the highly complex posterior PDF are discussed and a new adaptive algorithm, referred to as the tangential‐projection (TP) algorithm, allowing for an efficient approximate representation of the above manifold and the posterior PDF is presented. Using this approximation, expressions for calculating the uncertain predictive response are established. A numerical example involving noisy data is presented to demonstrate the proposed method. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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应用断裂带地震复发条件概率作为潜在震源区空间概率函数来确定潜在震源区地震的年平均发生率,并运用断层分段的结果,依据其给定震级地震的平均复发间隔,计算出了未来50年地震复发的条件概率。并以南北天山地震带为例进行了计算。结果表明,该方法是可行的,计算结果是适宜的。 相似文献
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软钢耗能器可靠度的分析方法 总被引:4,自引:0,他引:4
本文以低周疲劳破坏作为软钢耗能器的破坏模式,建立了弹塑性滞回变形幅值和滞回循环次数的概率分析方法。在此基础上,按照线性累积损伤准则,提出了大震作用下软钢耗能器可靠度的分析方法。最后,通过算例分析证明了上述方法的可行性。 相似文献
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Ing-Jia Chiou Ching-Ho Chen Wei-Lin Liu Shiao-Mei Huang Yu-Min Chang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2015,29(3):775-792
“Disaster risk assessment” is important in the planning of risk management strategies that reduce societal losses. However, governmental agencies in Taiwan generally assess risks that emerge from debris flows without adequately considering risk management and taking a systems approach. This work proposes an approach to thoroughly consider the interactive influence mechanism of debris flow disaster risk. Additionally, a systematic method for assessing disaster risks is developed. This proposed method can be used in the current risk assessment and as a basis for management strategy planning. Based on systems thinking, the components and attributes of a conceptual system of disaster risk management associated with debris flows in a river basin are identified. Subsequently, a conceptual mitigation–hazard–exposure–resistance framework and an indicator system for assessing the debris flow disaster risks in a river basin are identified. The disaster risks for each exposed community in each drainage zone can be systematically calculated based on the current status or plans of prevention and evacuation measures using the proposed indicator system. A case study of implementing the proposed methodology that involves the Chishan River Basin is presented, in which disaster risk according to the current status of prevention and evacuation measures is assessed. Drainage zones and communities with a significant debris flow disaster risk are located; this risk is associated with a lack of adequate prevention and evacuation measures that have been planned of government agencies. Analytical results indicate that the proposed methodology can systematically and effectively assess the disaster risks of a river basin. The proposed methodology provides a valuable reference for governmental agencies that must manage disaster risk associated with debris flows. 相似文献
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Water Resources - A generalized step-by-step statistical method for calculating the maximal precipitation sums of low probability is proposed. The method is applied to the case of daily... 相似文献
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震源定位是微地震监测技术要解决的主要问题.目前,井下微地震监测多采用走时拟合法计算震源位置.常规方法受到环境噪声、初至拾取误差、速度模型误差等因素的影响,定位结果存在一定误差.为了提高定位精度,本文提出了一种改进的基于网格搜索的微地震震源定位方法.本文方法根据P波的偏振特征参数计算概率密度函数求取震源方位角,并采用改进的目标函数和搜索算法计算震源的径向距离和深度.模型数据和实际资料的处理结果表明,本文方法具有较强的抗噪性,计算得到的震源方位角更加接近真实值;与常规目标函数相比,本文方法采用的目标函数具有更好的收敛性,其定位结果受初至拾取误差和速度模型误差的影响更小;本文提出的搜索算法能够消除由于错误拾取造成的观测到时中的异常值对定位结果的影响. 相似文献
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《国际泥沙研究》2020,35(6):621-635
The objective of the proposed method is to utilize a site investigation of a debris flow disaster and verify a real scale analysis to evaluate the impulsive load on an open sabo dam. The Nagiso debris flow disaster which occurred in Nagano in 2014, where damage caused by Typhoon Neogri was studied. The verification result of the site investigation demonstrated the weak components of the open Sabo dam experienced damage owing to the debris flow. A discrete element method is normally applied to a solid body to calculate an interaction function force with respect to the contact point between boulders and the dam. The numerical method initially concatenates elements that model the open Sabo dam. Moreover, the stiffness coefficient of flanges and coupling joints between pipes was expressed to utilize the sectional partition method to determine the structural characteristics. The method was improved to separate from the connecting elements beyond the boundary conditions. The debris flow model uses a water flow distribution model, and the debris flow flowed from 200 m upstream of the open sabo dam. Accordingly, the proposed method was examined to verify the primary cause of damage to the open sabo dam and used to reproduce the circumstances that evaluated the impulsive load occurrence mechanism in the case of a real disaster. In addition, the coupling joints between the hollow steel pipes utilized a ‘reproduction analysis’ for a real sabo dam and a ‘reinforced analysis’ for a reinforced sabo dam were applied to assess the weak point of the dam. 相似文献
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概述了太旧高速公路周缘地区(19个县市)的地震灾害。在寻建筑物的类型进行划分的基础上,用地震安全性评定的综合概率法计算每个单元遭遇烈度的概率,得到了各类建筑物的易损性矩阵,最后计算得出19个计算单元所有建筑物的破坏数量和预期经济损失,并对计算结果进行了分析和比较,最后提出防震减灾对策。 相似文献