损失分布和非结构损失对房屋建筑地易损性的影响          下载免费PDF全文

李文俊    曲哲    孙海林  熊政辉   《世界地震工程》2021,(4):109-121

房屋建筑的地震易损性是地震损失评估和地震巨灾风险模型的基础。作为房屋建筑的重要组成部分,各类非结构构件的损失在现有的易损性模型中并未得到足够重视。本文以一栋典型钢筋混凝土框架结构教学楼为对象,通过将房屋建筑中的各类构件划分为具有不同地震损伤特性和损失后果的易损性组,考察建筑内的损失分布和非结构损失对房屋建筑地震易损性的影响。分析结果表明:由于许多非结构构件在中小地震作用下即可能发生较严重的破坏,房屋建筑在中小地震下的易损性主要受非结构损失控制;随着地震动强度等级的不断提高,结构损伤渐趋严重,结构损失对整体建筑易损性的影响不断增大;在结构进入震后不可修状态之前,建筑不同楼层的损失分布是评估建筑地震损失时不可忽略的因素。  相似文献   

跨河水准测量的一种新方法     

廖晓和  王炳南  方元洪 《全球定位系统》2002,27(2):28-32

提出了GPS RTK技术在跨河水准测量中的新应用，分析了影响RTK高程实时解算精度的主要因素，RTK技术应用于跨河水准测量的实施原则、成果比较及精度分析，并提出了一些有益的建议。  相似文献   

超高效液相色谱法直接快速测定环境水样中硝基苯和苯胺   总被引：2，自引：1，他引：1  

黄毅  饶竹  刘艳  刘晨  郭晓辰 《岩矿测试》2012,31(4):666-671

建立了超高效液相色谱直接快速测定环境水样中硝基苯和苯胺的分析方法。取900μL水样与100μL乙腈混匀,用微孔滤膜(0.2μm,有机系)过滤。采用1.7μm小颗粒填料的BEH phenyl柱,以乙腈/醋酸铵溶液为流动相,硝基苯和苯胺分别用紫外和荧光检测器检测,分析时间仅1.1 min。硝基苯和苯胺的线性范围分别是0.485～4850μg/L和0.495～1978μg/L,方法检出限分别是0.194μg/L和0.099μg/L,相关系数均在0.995以上。硝基苯9.70μg/L、194μg/L、1940μg/L三个浓度水平回收率在98.3%～101%,相对标准偏差在1.11%～2.03%。苯胺9.89μg/L、198μg/L、1978μg/L三个浓度水平回收率在98.6%～104%,相对标准偏差在0.75%～5.85%。与传统液相分析方法相比,本方法线性范围更宽,灵敏度更高;直接进样简化了前处理环节,减少采样体积和有机试剂的使用;分析效率高,适用于地下水、地表水等多种水质样品中痕量到常量范围的硝基苯和苯胺快速测定。  相似文献   

直流电法电位测量中提高计算精度的方法技术研究     

张刚  贾正元 《现代地质》2012,26(6):1206-1211

直流电法是电法勘探中的重要分支,它是采用地表供电或者井中供电,在地面测量电位响应的勘探方法。利用地面测得的异常电位响应来分析地下的物性分布情况并推断地下矿体的空间位置。以采用方波供电方式所测得的电位数据为例来分析和研究计算人工电位的方法,结果表明:当采集电位数据质量好时,采用不同长度的窗口宽度计算得到的人工电位变化不大;当采集电位数据质量差时,采用不同长度的窗口宽度计算得到的人工电位变化比较大;假设加入不同比例的随机噪声理论电位数据,并采用不同窗口宽度进行理论计算人工电位时,取较小长度的窗口宽度计算得到的人工电位比较精确。这些为下一步的数据处理与解释奠定基础。  相似文献   

基于直接数字合成技术的随钻电阻率测井仪器的设计与实现     

潘光玮  冯泽东  何源  况丽丽  赵国臣  石峻峰 《物探与化探》2012,(2):253-255

介绍直接数字频率合成技术的基本原理,提出了应用直接数字频率合成芯片设计随钻电阻率测井仪器混频电路的硬件实现,通过Pspice仿真分析,证明了该系统实现简单,控制精度高。  相似文献   

POS与SWDC集成检校试验分析     

杨娜  韩晓冬  左建章  关艳玲 《测绘科学》2013,38(1):128-129,135

本文对高精度轻小型航空遥感系统对地检校场试验进行了分析,详细介绍数据处理的过程,重点给出利用PosAV系统后处理软件PosPac输出的导航结果计算影像外方位元素与空三获取外方位元素的比较结果,并在1∶500成图比例尺下,采用3种不同方法均匀采集检校场外业点进行直接地理定位精度验证,对于大比例尺测图是可以实现的。  相似文献   

USE OF TRITIUM IN HYDROLOGY     

BRYAN R. PAYNE 《水文科学杂志》2013,58(1):65-66

SUMMARY

The Coastal Plain aquifer of Israel, of Plio-Pleistocene Age, stretches from Binyamina in the North to the Gaza Strip in the South-a distance of about 112 km and has an average width of about 15 Km. The allowed withdrawal is estimated at about 200 MCM/year.

As a result of an average yearly withdrawal of 426 MCM/year during the last 10 years the water levels dropped to a dangerously low position (-2)-(-4) m below sea level at distances of 3–5 Km from the coast, causing sea water intrusion which, in Tel Aviv and Emek Hefer, endangered water supply wells.

As a counter-measure, artificial groundwater recharge through wells was practiced in Emek Hefer since 1959. Recharge was practiced in 7 wells at a rate of 6 MCM/year, the water coming from adjacent Cretaceous limestone aquifers.

In Tel Aviv a fresh water barrier was established in 1964 by injecting Lake Kinereth water into 17 wells during winter at a rate of 6 MCM/winter. In the rest of the Coastal Plain water was injected to the aquifer through about 40–45 wells at a total yearly rate of about 10–12 MCM.

Recharge by spreading is practiced in Yavneh at a rate of about 10–13 MCM per winter, also recharge by spreading is practiced with flood water of Nahal Shikma at a rate of up to 8 MCM/winter.  相似文献   

Topography-adjusted solar radiation indices and their importance in hydrology     

Nikos Mamassis  Andreas Efstratiadis  Ilektra-Georgia Apostolidou 《水文科学杂志》2013,58(4):756-775

Abstract

Solar radiation, direct and diffuse, is affected by surface characteristics, such as slope, aspect, altitude and shading. The paper examines the effects of topography on radiation, at multiple spatiotemporal scales, using suitable geometric methods for the direct and diffuse components. Two indices are introduced for comparing the direct radiation received by areas at the same and different latitudes. To investigate the profile of direct radiation across the whole of Greece, these are evaluated from an hourly to annual basis, via GIS techniques. Moreover, different approaches are examined for estimating the actual global radiation at operational spatial scales (sub-basin and terrain), according to the available meteorological data. The study indicates that the errors of typical hydrometeorological modelling formulas, which ignore the topographic effects and the seasonal allocation of direct and diffuse radiation, depend on the spatial scale and are non-uniformly distributed in time. In all cases, the estimations are improved by applying the proposed adjustment approaches. In particular, the adjustment of the measured global radiation ensures up to 10% increase of efficiency, while the modified Angström formula achieves slight (i.e. 2–4%) increase of efficiency and notable reduction of bias.

Editor Z.W. Kundzewicz

Citation Mamassis, N., Efstratiadis, A. and Apostolidou, I.-G., 2012. Topography-adjusted solar radiation indices and their importance in hydrology. Hydrological Sciences Journal, 57 (4), 756–775.  相似文献   

A study on dynamic shear strength on frozen soil-concrete interface     

Peng Lv  JianKun Liu  YingHui Cui 《寒旱区科学》2013,5(4):0408-0412

Using newly developed dynamic shearing devices, the dynamic shearing strength of frozen soil-concrete interface was studied experimentally. By placing concrete blocks in the lower half of the shear box and frozen soil sample in the upper part, a series of dynamic shear tests on their interfaces were carried out. The obtained results are summarized and the main influencing factors are revealed.  相似文献   

Parameter sensitivity in finite element analysis with constitutive models of the rate type     

Wolfgang Fellin  Alexander Ostermann 《国际地质力学数值与分析法杂志》2006,30(2):91-112

Non‐linear soil–structure interactions are usually analysed using an incremental finite element approach. There a constitutive subroutine provides for each element the stress increment for a given strain increment. In geotechnical calculations, uncertainties in material parameters and initial conditions are abundant. Sensitivity analysis can be a first step to account for such uncertainties. Sensitivities of the system response with respect to material parameters and initial conditions can be calculated by differentiating the whole numerical scheme. It turns out that the essential information from the constitutive subroutine are the derivatives of the stress increment with respect to the strain increment, as well as the derivatives with respect to material parameters and all state variables involved in the problem. We propose a method to compute these quantities numerically for any constitutive model that can be written in rate form and for any suitable integrator of such a model. We further present a concise way to supply the output of the sensitivity analysis to the designing engineer. Our theoretical investigations are illustrated with element tests and with a typical geotechnical application. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献