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1.
四川盆地综合地质、地球物理研究   总被引:9,自引:2,他引:9  
对四川盆地的地质、地球物理场特征进行了分析与探讨,对重力、航磁数据进行了延拓、求导,并反演计算了该盆地莫霍界面与磁性项、底界面,为认识盆地的断裂系统、地壳深部结构提供了基础,在此基础上收集了四川盆地的人工地震与测井资料,对该盆地进行了盆地沉降史的动态模拟,模拟表明,四川盆地在65Ma以后,属于稳定沉积阶段。  相似文献   

2.
简要介绍了《规划》的主要内容,叙述了编制《规划》的目的、指导思想、编制依据及设防目标,通过对县城的地震危险性分析与震害预测,提出了土地利用,场地区划、旧城改造,新建设防、避震疏散和生命线工程等方面具体要求,对震前应急准备与震后抢救灾作出了可行对策,对《规划》实施提出了分期目标。  相似文献   

3.
针对我国高层建筑常用的钢筋混凝土框架、框架-剪力墙、剪力墙等结构,就如何进行体系选择和截面预估,在理论与实践的结合上进行了阐述,并依据承载力、变形和抗震的要求,推导了简单易行的经验公式。这些经验公式对于方案选择和初步设计有很大的实用价值,经应用到设计实例中,节约了材料,缩短了设计周期,减少了计算机时,取得了良好的经济效果。  相似文献   

4.
几年来,镇江市地震办公室通过电视录像、知识竞赛、科普宣传周、新闻报道等形式,开展了防震减灾宣传教育工作。该文介绍了开展这项工作的概况及其所取得的社会效果,并进行了初步分析,认为宣传形式要因地、因时制宜,以通俗易懂,生活活泼,群众喜闻乐见为原则。  相似文献   

5.
闸涵结构的抗震分析与设计   总被引:4,自引:0,他引:4  
分析了闸涵结构空间薄壁体系的构造特点,研究了箱型结构-水体耦合的求解方程,导出了可用于箱型结构、闸室、渡槽壁面、坝面的动水压力附加质量的统一算式,介绍了地震反应的求解方法。以淮安立交地涵为例,考虑了结构、水体、地基的相互作用,计算了结构的自振特性,分析了7度地震作用时的动力反应,研究方法和研究成果可供闸涵结构的抗震分析和设计参考。  相似文献   

6.
2002年甘肃玉门5.9级地震灾害损失评估   总被引:2,自引:3,他引:2       下载免费PDF全文
2002年12月14日甘肃玉门发生了5.9级地震,造成了建筑物、构筑物和其他工程设施的破坏。震后开展了地震现场考察与震害评估工作,在充分了解灾区概况和自然环境、社会经济、产业支柱、人口及建筑物现状的基础上,将灾区划分为七个评估区,完成了66个点的震害抽样调查工作,根据地震灾害损失现场评估系统EDLES的要求,建立了有关数据库,做出了比较科学切合实际的经济损失评估结果。  相似文献   

7.
桥梁减震性能研究   总被引:1,自引:0,他引:1  
针对当前桥梁延性抗震及减、隔震设计的研究现状,阐述了在桥梁减、隔震设计中存在的问题,并采用编制的有限元非线性动力分析程序,对设置橡胶支座的一座简支梁桥的抗震性能进行了分析,检验了减、隔震支座的减震效果,比较了普通延性抗城和普通板式橡胶支座,铅芯橡胶支座的减震特点对减、隔震桥梁的延性地震响应特性进行了初步的探讨。  相似文献   

8.
一、前言     
一、前言我国自1966年邢台地震以来,在利用地下水(水位、水化)监测预报地震这一领域取得了很大的进展,相继建成了世界上最大的地下水地震观测台网,积累了大量的观测资料,观测到了丰富的地下水地震前兆现象,获得了一批中强以上地震震例,同时,在基础理论、地震...  相似文献   

9.
分析了采用细胞自动机研究波动问题的建模方法,针对一维、均匀、各向同性固体介质中弹性纵波的微观机制,借用一经典弹簧振子模型、细胞自动机格子气模型,以及量子力学中的无限深势阱模型,建立了一个细胞自动机有限深势阱模型,从量子力学角度出发,基于介观物理和纳米概念,以微观精子的德布罗意假设为基础,利用薛定谔方程,讨论了该模型中粒子(分子组)的振动速度与粒子物质波波速之间的联系,给出了模型中的波动方程,得出ζ=Vp(ζ为粒子振动速度,Vp为物质波纵波波速)。同时还讨论了模型中粒子的大小和能量传递问题,引入引力场,得出了能量及引力势的量子化条件,另外,对声波速度、格子气粒子振动速度和本文模型中分子组振动速度进行了比较;还对本文模型中的粒子能量分布作了分析。  相似文献   

10.
薄万举 《内陆地震》1994,8(3):221-228
在原来工作的基础上①②[7],对拟合、滑动外推、聚类分析、模糊综合评判等各个环节做了适当的改进.同时,引入概率统计中的有关知识.选择一个相对最佳评判方案,用京、津、唐地区流动点短水准,短基线资料进行了地震预报的研究,为用形变资料经过评判统计进行地震预报提供了一种可能性。最后,以讨论的方式给出了应用实例.  相似文献   

11.
The problem of predicting future short-term chemical behaviour in acidic and acid-sensitive streams is addressed. A relatively simple method is presented which combines a chemical technique for splitting the hydrograph into ground water and soil water components, based on the conservative component acid neutralization capacity, with the long-term hydrochemical model (MAGIC) in a ‘two-box’ mode. This method, coupled with a chemical speciation program (ALCHEMI), is used to assess short-term variations in stream chemistry with change in atmospheric deposition chemistry. The method is applied for a semi-natural moorland catchment in mid-Wales (Afon Gwy). For both hydrogen ion and inorganic aluminium, the modelled stream mixing relationships are non-linear, particularly at low hydrogen ion concentrations. The results also show that the relationship between hydrogen ion and inorganic aluminium concentrations varies with time in the stream. This result has important implications as it implies that aluminium concentrations will not recover, with reduced anthropogenic sulphur deposition, as rapidly as has previously been thought. Two methods, for use with critical load evaluation of ecological stress, are presented for describing the changes occurring: the hydrogen ion and inorganic aluminium concentration duration curve; the hydrogen ion and inorganic aluminium incident frequenty diagram.  相似文献   

12.
李蔚 《山西地震》2005,(4):37-39
从2004年12月印度洋发生地震海啸造成的灾难中得到启示,从完善我国的应急救援、防灾救灾体系、法律法规体系,预测系统、快速反应预警系统以及启动应急预案、组建应急指挥体系、组织应急救援队伍、实施应急救援等方面,阐述了建立应急救援指挥机构和各种应急队伍的必要性,绘制了灾害处理应急流程图,分析了应急队伍所应承担的任务,提出在我国应尽快建立地震海啸预警机制的建议。  相似文献   

13.
A simplified multisupport response spectrum method is presented.The structural response is a sum of two components of a structure with a first natural period less than 2 s.The first component is the pseudostatic response caused by the inconsistent motions of the structural supports,and the second is the structural dynamic response to ground motion accelerations.This method is formally consistent with the classical response spectrum method,and the effects of multisupport excitation are considered for any modal response spectrum or modal superposition.If the seismic inputs at each support are the same,the support displacements caused by the pseudostatic response become rigid body displacements.The response spectrum in the case of multisupport excitations then reduces to that for uniform excitations.In other words,this multisupport response spectrum method is a modification and extension of the existing response spectrum method under uniform excitation.Moreover,most of the coherency coefficients in this formulation are simplified by approximating the ground motion excitation as white noise.The results indicate that this simplification can reduce the calculation time while maintaining accuracy.Furthermore,the internal forces obtained by the multisupport response spectrum method are compared with those produced by the traditional response spectrum method in two case studies of existing long-span structures.Because the effects of inconsistent support displacements are not considered in the traditional response spectrum method,the values of internal forces near the supports are underestimated.These regions are important potential failure points and deserve special attention in the seismic design of reticulated structures.  相似文献   

14.
以2008—2017年腾冲地震台井水位记录的同震响应事件为研究对象,系统分析该井水位的同震响应特征,结合井孔地质背景条件,对同震响应机理进行初步探讨。结果表明:腾冲地震台井水位同震响应能力随着震级增大而逐渐增强;因井震距不同,同震响应主要表现为近震阶降—复原型和远震振荡型变化;同震响应幅度随震级增大而增大,随井震距增大而减小,且水位同震变化受震级与井震距的影响力基本相当;震级越大,同震响应持续时间越长;发生井水位同震响应的地震分布具有明显区位型特点。分析认为,振荡型同震响应机理与面波作用有关,阶降—复原型同震响应机理可能与腾冲地震台观测井所处地质构造有关。  相似文献   

15.
反应谱的标定是抗震设计的基础工作之一,模拟退火算法是基于模拟固体退火过程而提出的多参数优化组合方法。本文提出将模拟退火算法应用于设计反应谱的标定,并概述了模拟退火算法的基本原理及特点,介绍了运用MATLAB基于模拟退火算法对反应谱进行标定的过程。检验了将模拟退火算法应用于场地相关谱标定的可行性和合理性,给出了将其应用于工程场地地震安全性评价中设计反应谱标定实例。通过检验和实例分析可以看出,基于模拟退火算法的反应谱标定方法所给出的设计反应谱谱形真实地反映了原地震反应谱的特征,较客观的反映了场地相关反应谱的峰值和周期特征。  相似文献   

16.
抗震设计规范中的场地设计反应谱是一般工程抗震设计的依据,各国的抗震设计规范对场地设计反应谱的规定不尽相同。主要表现在反应谱的形状和谱参数的差异。本文收集了若干国家的抗震设计规范;在总结各国抗震设计规范中关于场地设计反应谱规定的基础上,对中国、美国、日本、欧洲、土耳其和智利等有代表性的国家和地区的抗震设计规范进行分析和对比研究;总结了我国抗震设计规范场地设计反应谱的演化历史和发展过程;提出了进一步开展这一领域研究工作的若干建议,本文的工作对从事场地设计反应谱研究的科技人员有重要的参考价值。  相似文献   

17.
In this paper, statistics are taken on the co-seismic response of underground fluid in Yunnan to the Nepal MS8.1 earthquake, and the co-seismic response characteristics of the water level and water temperature are analyzed and summarized with the digital data. The results show that the Nepal MS8.1 earthquake had greater impact on the Yunnan region, and the macro and micro dynamics of fluids showed significant co-seismic response. The earthquake recording capacity of water level and temperature measurement is significantly higher than that of water radon and water quality to this large earthquake; the maximum amplitude and duration of co-seismic response of water level and water temperature vary greatly in different wells. The changing forms are dominated by fluctuation and step rise in water level, and a rising or falling restoration in water temperature. From the records of the main shock and the maximum strong aftershock,we can see that the greater magnitude of earthquake, the higher ratio of the occurrence of co-seismic response, and in the same well, the larger the response amplitude, as well as the longer the duration. The amplitude and duration of co-seismic response recorded by different instruments in a same well are different.Water temperature co-seismic response almost occurred in wells with water level response, indicating that the well water level and water temperature are closely related in co-seismic response, and the well water temperature seismic response was caused mainly by well water level seismic response.  相似文献   

18.
Numerous studies have examined the event‐specific hydrologic response of hillslopes and catchments to rainfall. Knowledge gaps, however, remain regarding the relative influence of different meteorological factors on hydrologic response, the predictability of hydrologic response from site characteristics, or even the best metrics to use to effectively capture the temporal variability of hydrologic response. This study aimed to address those knowledge gaps by focusing on 21 sites with contrasting climate, topography, geology, soil properties, and land cover. High‐frequency rainfall and discharge records were analysed, resulting in the delineation of over 1,600 rainfall–runoff events, which were described using a suite of hydrologic response metrics and meteorological factors. Univariate and multivariate statistical techniques were then applied to synthesize the information conveyed by the computed metrics and factors, notably measures of central tendency and variability, variation partitioning, partial correlations, and principal component analysis. Results showed that some response magnitude metrics generally reported in the literature (e.g., runoff ratio and area‐normalized peak discharge) did not vary significantly among sites. The temporal variability in site‐specific hydrologic response was often attributable to the joint influence of storage‐driven (e.g., total event rainfall and antecedent precipitation) and intensity‐driven (e.g., rainfall intensity and antecedent potential evapotranspiration) meteorological factors. Mean annual temperature and potential evapotranspiration at a given site appeared to be good predictors of hydrologic response timing (e.g., response lag and lag to peak). Response timing metrics, particularly those associated with response initiation, were also identified as the metrics most critical for capturing intrasite response variability. This study therefore contributes to the growing knowledge on event‐specific hydrologic response by highlighting the importance of response timing metrics and intensity‐driven meteorological factors, which are infrequently discussed in the literature. As few correlations were found between physiographic variables and response metrics, more data‐driven studies are recommended to further our understanding of landscape–hydrology interactions.  相似文献   

19.
Short┐termandimminentanomaliesofearth┐quakeofloadandunloadresponseratioofthewelleveltoearthtidesZHAO-DONGZHANG(张昭栋)1)XUE-ZHO...  相似文献   

20.
加卸载响应比理论在中强地震(7〉M≥6)预测中的应用   总被引:6,自引:2,他引:6  
本文运用加卸载响应比理论对中强地震前的加卸载响应比的变化进行了研究。结果表明,中强地震前加卸载响应比明显上升,表现为三种不同的形态,持续时间为半年到两年。  相似文献   

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