应用模糊模式识别研究晋冀蒙交界区的中强地震

应用模糊数学中的模式识别方法,从晋冀蒙交界区公元前294年至1987年Ms≥4 3/4级的地震序列中,选取了4个预报地震震级的指标,给出了识别Ms∈[5.5,6.0]和Ms>6.0的方程。识别结果表明,1989年至1990年在本文讨论的范围内,将有一次Ms>6.0的地震发生。     

云南地区地震活动的有序迁移图像

重点追踪了云南地区中强震的动态图像 ,发现在云南地区强震活跃期前 1～ 4a出现中强震的有序迁移 ,有序迁移的中强震预示了活跃期强震时空分布的总体格局 ,80 %的强震发生在这些中强震 15 0km范围内。有序迁移结束后 2d至 11个月发生活跃期的首次强震 ,其中 75 %在 3个月内。文中介绍了强震的等间距迁移、强震活跃期后期中强震的有序迁移 ,巨震前后大震的有序迁移和中等地震的定向迁移与部分震例 ,但地震活动有序迁移图像的机理尚待研究     

Design energy input spectra for moderate‐seismicity regions

This paper proposes energy input spectra applicable to seismic design of structures located in low‐to‐moderate‐seismicity regions. These spectra represent the load effect, in terms of input energy, of the most severe earthquake that the construction might encounter during its lifetime. The spectra have been derived through dynamic response analyses of over 100 ground motion records obtained from 48 earthquakes that have occurred in Spain. An empirical equation for estimating the energy input contributable to damage from the total input energy is also suggested. This equation takes into account both the damping and the degree of plastification of the structure. Finally, the proposed design energy input spectra are compared with the provisions of the current Spanish Seismic Code and with the response spectra of recent earthquakes that have occurred in Turkey and Taiwan. Copyright © 2002 John Wiley & Sons, Ltd.     

基于生态安全的湖北省秭归县城镇适度规模研究

国家层面社会经济与城镇化的转型发展及长江经济带的战略推进为三峡库区城镇的健康可持续发展确定了方向。以湖北省秭归县为例,运用生态足迹和生态安全格局方法,从资源消耗和土地安全视角分别对县域和中心城区的适度人口和用地规模进行测算。结果表明:2015年秭归县域适度人口规模为31.03万人,用地规模244.64km~2,预留用地132.26 km~2,而秭归中心城区适度人口规模为21.01万人,用地规模18.91 km~2,预留空间约9.01万人、11.82 km~2,表明秭归县域人口已超出生态限制,且多处于农村,应控制生态资源消耗,加强构建县城—重点镇—基础镇的城镇体系,逐步引导农村人口向秭归城镇体系各节点合理转移。     

珠三角城市旅游经济空间差异与协调发展战略研究

基于珠三角九城市1999-2008年主要旅游经济指标,分析了珠三角城市旅游经济空间差异的基本特征,包括国内旅游收入、海外旅游收入空间差异的总体变化,城市旅游经济发展水平与旅游产业地位的分异性,近年来核心城市与外围城市在旅游规模位序、旅游发展状态方面的变化特点;最后提出缩小珠三角城际旅游经济差异的协调发展战略,包括深化城际合作,调整旅游发展模式;构建三大旅游圈和八大旅游板块;加快边缘地区的旅游发展步伐;将核心城市的扩散效应与周边城市的自主发展相结合等.     

湖南中强地震活动地区Ⅱ类场地放大效应研究

利用工程场地地震安全性评价工作中大量实际钻孔和土工实验资料,建立了实际工程场地模型,在50年超越概率为63%、10%、2%共3种地震动输入下,采用SHAKE91和ELSSRA两种等效线性化方法,研究了湖南省Ⅱ类场地土层的放大效应.计算结果表明:湖南省50年超越概率10%的场地效应放大因子为1.30,若使用<中国地震动参数区划图(GB18306-2001)>认定的1.25系数,将低估湖南中强地震活动地区的场地放大效应.湖南省50年超越概率63%、10%、2%这3个设定水准的场地效应放大因子满足1.10:1.00:0.95的关系.这些结果有益于为湖南省提供更为合理的抗震设防标准.     

"生态围垦"在浙江省经济可持续发展中的意义

围垦不仅是浙江省缓解土地资源的一条重要途径,而且在该省经济发展中发挥了巨大作用.随着浙江省经济可持续发展总体目标的提出,对围垦的要求上升到了"生态围垦"的高度:这就是坚持围垦系统规划的生态性;大力开展设计创新,提高围涂技术水平,以符合"生态围垦"的设计要求;创新施工工艺,优化施工组织,以满足"生态围垦"工程的建设要求;坚持适度分期开发,积极开展绩效评估,以适应"生态围垦"工程的运行管理要求.以科技进步为基础的"生态围垦",对推动浙江省经济可持续发展有着战略性的意义.     

地电阻率中短期异常与地震的关系

研究了196次Ms3.2～7.9地震（94％以上为Ms4.0地震）前1139次（道次）地电阻率中短期异常,得到以下结果:① 异常时间与震级之间为非线性增长关系,大致分为３个阶段:Ms5.0地震,异常时间随震级增大基本上是快速的线性增长;5.0＜Ms＜6.5地震,增长速度逐步变小;Ms6.5地震,增长速度很小．② 异常幅度与震级之间为非线性的指数式增长关系,也大致分为３个阶段:Ms5.0地震,随震级增大异常幅度增长很小;5.0＜Ms＜6.5地震,逐步趋于加速增长;Ms6.5地震,加速增长．定性解释、并利用流变介质模型探讨了异常时间、幅度与震级之间非线性关系的物理机制．      

瑞昌地区地震构造条件分析

通过分析瑞昌地区区域地震构造背景、地壳结构、地球物理场及新构造运动特征,结合最新断裂构造考察研究成果,研究该地区主要断裂活动性,并探讨中强地震的活动特征及其发震构造,研究成果对于瑞昌地区未来强震危险性评估具有参考意义。     

Multi-hazard performance assessment of a transfer-plate high-rise building

Many urban areas are located in regions of moderate seismicity and are subjected to strong wind. Buildings in these regions are often designed without seismic provisions. As a result, in the event of an earthquake, the potential for damage and loss of lives may not be known. In this paper, the performance of a typical high-rise building with a thick transfer plate (TP), which is one type of building structure commonly found in Hong Kong, is assessed against both earthquake and wind hazards. Seismic- and wind-resistant performance objectives are fi rst reviewed based on relevant codes and design guidelines for high-rise buildings. After a brief introduction of wind-resistant design of the building, various methodologies, including equivalent static load analysis (ESLA), response spectrum analysis (RSA), pushover analysis (POA), linear and nonlinear time-history analysis (LTHA and NTHA), are employed to assess the seismic performance of the building when subjected to frequent earthquakes, design based earthquakes and maximum credible earthquakes. The effects of design wind and seismic action with a common 50-year return period are also compared. The results indicate that most performance objectives can be satisfi ed by the building, but there are some objectives, such as inter-story drift ratio, that cannot be achieved when subjected to the frequent earthquakes. It is concluded that in addition to wind, seismic action may need to be explicitly considered in the design of buildings in regions of moderate seismicity.