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Introduction With rapid development of national economy, urbanization has been speeded up in China, and several city groups or city belts with extra-large cities as their centers have been formed. For example, Pearl River Delta urbanized area surrounds Guangzhou City, Shenzhen City, Zhuhai City; Yangtze River Delta urbanized area surrounds Shanghai City, Suzhou City, Wuxi City, Nanjing City, Hangzhou City; Beijing-Tianjin-Tangshan urbanized area surrounds Beijing City, Tianjin City… 相似文献
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Introduction With rapid development and advancement of economy and society, lots of city groups or city belts with ex-tra-large cities as their centers have been formed in China. The regions these city groups lie in usually have well-developed economy, dense population, and are regional politics and culture centers. Some groups lie in the regions with high level of earthquake activity, such as the Surrounding Capital City Group with the centers of Bei-jing and Tianjin. Once a large earthqua… 相似文献
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Applying the idea of renormalization group and fractal theory, we analyzed seismic hierarchy feature detailed. Based on the
seismogenic model of “fracture penetration”, we built a model of seismic critical instability, deduced its recursion relationship
of renormalization, and estimated the probability of its critical instability P.
The paper is supported by the Chinese Joint Seismological Science Foundation, Project No. 950085. 相似文献
4.
The Influence of Earth Temperature on the Dynamic Characteristics of Frozen Soil and the Parameters of Ground Motion on Sites of Permafrost 总被引：1，自引：0，他引：1
Wang Lanmin 《中国地震研究》2004,18(1):1-12
Earth temperature is one of the most important factors influencing the mechanical properties of frozen soil. Based on the field investigation of the characteristics of ground deformation and ground failure caused by the Ms8.1 earthquake in the west of the Kuniun Mountain Pass,China, the influence of temperature on the dynamic constitutive relationship, dynamic elastic modulus, damping ratio and dynamic strength of frozen soil was quantitatively studied by means of the dynamic triaxial test. Moreover, the characteristics of ground motion on a permafrost site under different temperatures were analyzed for the four profiles of permafrost along the Qinghai-Xizang (Tibet) Railway using the time histories of ground motionacceleration with 3 exceedance probabilities of the Kunlun Mountains area. The influences of temperature on the seismic displacement, velocity, acceleration and response spectrum on permafrost ground were studied quantitatively. A scientific basis was presented for earthquake disaster mitigation for engineering foundations, highways and underground engineering in permafrost areas. 相似文献
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Citation Littlewood, I. G., Croke, B. F. W. & Young, P. C. (2011) Discussion of “Effects of temporal resolution on hydrological model parameters and its impact on prediction of river discharge” by Y. Wang, B. He & K. Takase (2009, Hydrol. Sci. J. 54(5), 886–898). Hydrol. Sci. J. 56(3), 521–524. 相似文献
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Ｉｎｆｌｕｅｎｃｅｏｆｇｅｏｓｔａｔｉｃｓｔｒｅｓｅｓｏｎｐｅｒｍｅａｂｉｌｉ┐ｔｙｏｆｊｏｉｎｔｅｄｒｏｃｋｍａｓｅｓＣＵＡＮＧ－ＢＢＩＮＧＺＨＯＵ（周创兵）ａｎｄＷＥＮ－ＬＩＮＸＩＯＮＧ（熊文林）ＷｕｈａｎＵｎｉｕｅｒｓｉｔｙｏｆＨｙｄｒａｕｌ... 相似文献
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IntroductionQinghai-Xizang(QingzangorTibetan)plateauisthemostremarkableactivecollisionbeltontheEarth.Itsaveragealtitudeis5km,itscrustthicknessupto70kmanditsareaabout7?05km2.Inrecenttwentyyears,withthegeophysicalobservationdatagettingmoreandmore,manydy-namicmodelsaboutcrustthickeningandTibetanuplifthavebeenputforward(Harrison,etal,1992;LI,1995;ZENG,etal,1994;ZHONG,DING,1996;XIAO,WANG,1998).Theycanbedividedintotwotypes.ThefirsttypecharacterizesthattheconvergencebetweenIndiaandEura-s… 相似文献
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Huang Qingtuan 《中国地震研究》2007,21(2):210-224
On the southeast coast of Fujian and its adjacent area, the NE-trending Changle-Zhao′an fault zone and several NW-trending faults that are genetically related to the former are well developed. With micro-relief analysis, the paper deals with the Quaternary activity of the faults and the tectonic stress field since the late Pleistocene in this region. The results indicate that the micro-relief of the NE-trending Changle-Zhao′an fault zone and the genetically related NW-trending faults is characterized by vertical and horizontal movements since the Quaternary; the faults in the region have undergone two active stages since the Quaternary, i.e. early Quaternary and late Pleistocene; since the late Pleistocene, the movement of the NE-trending faults showed a right-lateral strike-slip, while that of NW-trending faults a left-lateral strike-slip, indicating a NWW-SEE oriented horizontal principal stress of the regional tectonic stress field 相似文献
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Yan Zhang Fuqiong Huang Guijuan Lai Institute of Geophysics China Earthquake Administration Beijing China China Earthquake Networks Center Beijing China 《地震学报(英文版)》2009,(6)
Based on isotropic linear poroelastic theory and under the undrained condition,we summarize three equations connecting the Skempton’s coefficient B with the groundwater level.After analysis,we propose a method to calculate the Skempton’s coefficient B according to the relationship between water level and tidal strain.With this method we can get the value of B without the earthquake occurrence,which can provide the high frequency waves for research.Besides,we can also get the in-suit Skempton’s coefficient B... 相似文献
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Experimental study on three dimensional movements of particles Ⅱ Effects of particle diameter on turbulence characteristics 总被引：1，自引：1，他引：0
Based on the 3D PTV （Particle Tracking Velocimetry） measuring system, the 3D movement characteristics of particles with four different diameters were investigated. Under specific flow conditions, the impact of particle diameters on 3D motion of particles was studied, and the turbulence characteristics were analyzed by different statistical methods. The results showed that the turbulence intensity of coarse particle decreased as the diameter increased. In near wall region, the probability density distributions of longitudinal and vertical fluctuation velocities both deviated from the normal distribution; while in the outer region, the probability density distribution of vertical fluctuation velocity approximately agreed with the normal distribution. 相似文献
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An understanding of the behavior of cohesive sediment is required to solve various engineering problems such as scour around bridge elements, mitigation of soil erosion, pavement design, river bed degradation,stable channel design. Pavement foundation designers principally use the California bearing ratio(CBR)to describe the subgrade and subbase materials and their strength. Several laboratory experiments were done to study the variation in the CBR of cohesive mixtures comprised of clay-gravel m... 相似文献
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Introduction The Lg phase plays a central role in nuclear test detection, discrimination, and yield estima-tion because of its stability in propagation, but the excitation mechanisms of Lg phase are not fully understood. Regional Lg is a short-period guided wave composed mainly of a sequence of multi-ply reflected post-critical S waves trapped in the crustal wave guide. Several studies carried out recently (Gupta et al, 1992; Patton and Taylor, 1995; Gupta et al, 1997; Wallace, 1991) have … 相似文献
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This paper reviews briefly the progresses made during the last four years (1999～2002) in study of seismotectonics in China, especially appraises the achievements in the fields of the crustal and upper mantle‘s structure, the active faults and tectonic setting of large earthquakes, the crustal deformation, and the numerical simulation. Most earth-quakes occurred in China belong to continental earthquakes. Therefore, Chinese seismologists pay more attention to the continental earthquakes. Based on improvements of the observation systems in China during the ninth Five-Year Plan, the studies on seismotectonics have achieved great progresses. 相似文献
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In this paper, we briefly describe the general destruction caused by historic earthquakes in major cities of China, preliminarily analyze the heaviness and widespread occurrence of earthquakes in cities of China, and suggest that research on scenario earthquakes in cities should be developed as a part urban disaster reduction research. 相似文献
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For magnetotelluric sounding (MT), many processing methods based on power spectrum have put forwardlots of hypotheses, such as MT signals are Gaussian, linear and minimum-phase. If practical signals do not satisfythese requirements, the results will have a few problems as follows. Firstly, when signals are non-linear andnon-Gaussian, the information of the earth contained in the MT signals cannot be sufficiently extracted; Secondly,when signals are non-Gaussian and non-minimum phase, the p… 相似文献
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The seismic hazard of research area is evaluated by probabilistic analysis method for three different seismic statistical zone scenarios.The influence of uncertainty in seismic statistical zone delimiting on the evaluation result is discussed too.It can be seen that for those local sites along zone‘s border or within areas with vast change of upper bound magnitude among different scenarios the influence on seismic hazard result should not be neglected. 相似文献
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《地震学报(英文版)》1998,(4)
Ｒｅｓｅａｒｃｈｏｎｐｒｏｂａｂｉｌｉｔｙｏｆｓｅｉｓｍｉｃｃｒｉｔｉｃａｌｉｎｓｔａｂｉｌｉｔｙｏｎｂａｓｉｓｏｆ＇＇ｆｒａｃｔｕｒｅｃｏｌｌｕｓｉｏｎ＇＇ｍｏｄｅｌＳＨＩ－ＹＯＮＧＺＨＯＵ１）（周仕勇）,ＬＩＮＧ－ＲＥＮＺＨＵ１）（朱令人）,ＭＡ... 相似文献
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李兴才 《地震学报(英文版)》1994,7(3):409-414
Ｐｒｏｍｏｔｉｎｇｅｆｆｅｃｔｓｏｆ１９７５ＨａｉｃｈｅｎｇｆｏｒｅｓｈｏｃｋｓｏｎｔｈｅｏｃｃｕｒｒｅｎｃｅｏｆｔｈｅｍａｉｎｓｈｏｃｋＸｉｎｇ－ＣａｉＬＩ（李兴才）（ＩｎｓｔｉｔｕｔｅｏｆＧｅｏｐｈｙｓｉｃｓ，ＳｔａｔｅＳｅｔｉｓｍｏｌｏｇｉｃａ... 相似文献
20.
Limo TANG Xingkui WANG 《国际泥沙研究》2009,24(2):159-168
Based on the three Dimensional Particle Tracking Velocimetry （3D PTV） system, the characteristics of motion of particles with four different diameters were investigated under the steady flow conditions The longitudinal average velocity profiles of these particles were in accordance with Log-law, while the vertical and transverse velocities remained very low with minimal fluctuation. The time-average velocity of particles in the bed load layer was 8.50u., close to Bagnold＇s assumptionUn -60. The vertical concentration distribution of particles in the suspension region agreed with the Rouse equation. When the diameter of particles was relatively large, there existed an evident concentration gradient in the bed load layer. 相似文献