钢筋混凝土核心筒体抗震性能试验研究   总被引：17，自引：5，他引：17  

吕西林  李俊兰 《地震工程与工程振动》2002,22(3):42-50

本文对两组五个钢筋混凝土核心筒试件进行了低周反复荷载试验，研究了不同轴压比和剪跨比的核心筒破坏机理、承载能力、延性和耗能能力等方面的抗震性能。结果表明，轴压比对核心筒的抗震性能有较大影响。  相似文献   

Formation of diapiric structure in the deformation zone,central Indian Ocean: A model from gravity and seismic reflection data     

K. S. Krishna  D. Gopala Rao  Yu. P. Neprochnov 《Journal of Earth System Science》2002,111(1):17-28

Analyses of bathymetry, gravity and seismic reflection data of the diffusive plate boundary in the central Indian Ocean reveal a new kind of deformed structure besides the well-reported structures of long-wavelength anticlinal basement rises and high-angle reverse faults. The structure (basement trough) has a length of about 150 km and deepens by up to 1 km from its regional trend (northward dipping). The basement trough includes a rise at its center with a height of about 1.5km. The rise is about 10 km wide with rounded upper surface and bounded by vertical faults. A broad freeair gravity low of about 20 mGal and a local high of 8 mGal in its center are associated with the identified basement trough and rise structure respectively. Seismic results reveal that the horizontal crustal compression prevailing in the diffusive plate boundary might have formed the basement trough possibly in early Pliocene time. Differential loading stresses have been generated from unequal crust/sediment thickness on lower crustal and upper mantle rocks. A thin semi-ductile serpentinite layer existing near the base of the crust that is interpreted to have been formed at mid-ocean ridge and become part of the lithosphere, may have responded to the downward loading stresses generated by the sediments and crustal rocks to inject the serpentinites into the overlying strata to form a classic diapiric structure.  相似文献   

高层建筑深层平板载荷试验的研究   总被引：2，自引：1，他引：2  

杨国春  吴银柱等 《地质与勘探》2002,38(4):90-93

介绍了高层建筑深层平板载荷试验方法的技术现状及一套测试深度可达百米，测试精度高且不受深度影响的新型深层平板载荷试验装置，提出了深层载荷试验中存在的关键性技术问题及解决措施，并给出了实测试验成果。  相似文献   

CFG桩复合地基承载性状的实验研究   总被引：15，自引：0，他引：15  

潘纪顺  刘志伟等 《地质与勘探》2001,37(4):92-94

通过CFG桩复合地基载荷试验和桩土应力比试验的研究，探讨了CFG桩复合地基承载特性。  相似文献   

Mechanical behavior and microstructural variation of loess under dynamic compaction   总被引：3，自引：0，他引：3  

R. L. Hu  M. R. Yeung  C. F. Lee  S. J. Wang 《Engineering Geology》2001,59(3-4):203-217

The laboratory dynamic compaction test was used to study the effects of dynamic impact loads on the shear strength characteristics of loess. Loess specimens were compacted by different numbers of blows and their shear strengths measured. The experimental results revealed that the shear strength varies in stages with the number of blows. During the initial stage, the shear strength increases with the number of blows. It reaches a peak value and then decreases with the number of blows. To reveal the relationship between this alternation in shear strength and microstructural variation, quantitative microstructural analyses were performed on some tested specimens at different stages of strength evolution. This microstructural study demonstrated that the variation of shear strength is directly related to the alteration of microstructure. It is concluded that the shear strength of loess is basically controlled by its microstructural state. Growing particle size heterogeneity, varying particle orientations and increasing microstructural damage are the main causes of the alternation of shear strength.  相似文献   

沙漠砂承载力室内综合性原位测试模拟试验研究     

刘辉  张喜发  张文殊 《吉林大学学报(地球科学版)》2001,31(2):168-172

为更好地满足沙漠油田地面工程建设的需要 ,对沙漠砂采用平板振动器分层制样 ,进行了平板载荷、静力触探和标准贯入等一系列室内模拟试验。试验数据回归分析表明 :静力触探试验中 ,《TJ2 1- 77规范》与《JTJ2 40 - 97规范》等规范建议的承载力值偏小。标准贯入试验中 ,《GBJ7- 89规范》、《TJ7- 74规范》与《JTJ2 40 - 97规范》等规范砂土承载力推荐值与本文试验回归值相差较大 ,偏于保守 ,如将其用于沙漠地基勘查评价和基础设计中将造成很大浪费 ;现有一些规范在用SPT和CPT确定粉细砂承载力时存在矛盾 ,不够协调 ,因此不适用于沙漠地区 ,必须制定新的标准。  相似文献   

GPS引导下的多角度遥感图像自动匹配   总被引：1，自引：0，他引：1  

高峰 《国土资源遥感》1997,8(4):47-53

随着航天和计算机技术的进步,多角度遥感目前又一次成为遥感基础研究的新热点,不同于以往的传统垂直观测方式,它不仅提供了地物的空间光谱信息,还提供了地物的结构特征信息,是定量化遥感的途径之一。多角度遥感也使得遥感图像处理更加复杂,多角度遥感图像的配准便是要解决的关键技术之一,多角度遥感图像成像的特殊性决定了纯粹利用图像信息进行的匹配是较为困难的。本文以法国POLDER（POL arizationand Directionality of Earth's Reflectance）多角度航空遥感试验为例,介绍POLDER多角度遥感图像自动匹配的方法,首先用GPS进行定位引导,精度在100m左右,然后在初步定位的基础上,用图像灰度特征和结构特征进行精确配准,自动定位精度小于30m,最后采用局部最小误差控制点对图像进行重采样处理,并直接提取航空平台的地物二向性反射信息。  相似文献   

Quasi-static poroelastic parameters in rock and their geophysical applications     

Herbert F. Wang 《Pure and Applied Geophysics》1993,141(2-4):269-286

The constitutive equations of poroelasticity contain four static moduli. Different sets of moduli are reviewed in the context of their laboratry measurement and their geophysical applications. One complete set consits of the drained bulk modulus and Poisson's ratio, and their undrained counterparts. Skempton's coefficient (ratio of pore pressure increment to mean stress increment under undrained conditions) and the Biot-Willis parameter serve equally well for the undrained bulk modulus and Poisson's ratio, because they permit the drained and undrained moduli to be related to each other. Time dependence is introduced into poroelastic behavior through Darcy's law. Geophysical applications that can be approximated by undrained conditions (fast loading) include seismicity, tidal and barometric loading, and tectonic compression. Several of these problems are most directly formulated in terms of Skempton's coefficient, undrained Poisson's ratio, and hydraulic diffusivity.  相似文献   

实验均衡二十年     

李雄 《地球科学进展》1992,7(2):12-16

回顾了利用响应函数技米研究地球均街己取得的主要成果并提出了研究中值得注意的一些问题。
     相似文献   

列车荷载作用对某些前兆观测的影响   总被引：3，自引：0，他引：3  

万登堡  王家彬 《地震》1994,(3):91-94

本文针对列车荷载作用对地震前兆观测的影响，在野外开展了水位，测震，水温，地电等多项目的对比观测，结果表明：列车荷载作用是确实存在的；水位，测震对地壳应力－应变反映是灵敏的。  相似文献