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141.
论述了电阻应变式传感器的工作原理及在高应变桩基动测中的应用,并就消除非线性测量误差和温度补偿问题做了具体地分析。 相似文献
142.
介绍了4种单项形变,应变资料信息提取方法,即多点组信息法,信息标准化方法,畸形参数法和信息丛集度法,按定义,μ值亦可归属多点相法,故对μ值法亦作介绍,这些方法提取出了新的信息,具有不同的新特点和应用范围,在实际应用中均初步取得了较好的效果。 相似文献
143.
Mariya I. Yurkina 《Studia Geophysica et Geodaetica》1996,40(1):9-13
Summary On the basis of the fundamental relations of the Molodensky's Earth's figure theory (1945), admitting the inequality of the
gravity potentials at the Major Vertical Datum W0 and on the surface of the reference level ellipsoid U0, and taken into account that potential W0 enters into equations directly, it is recomended, W0 should be adopted as a primary geodetic constant. Parameters of the best fitting ellipsoid are not needed for the solution
of geodetic problems and for the investigation of the Earth's gravity field. The reason for requiring the reference and actual
fields be close is only that the boundary-value problem can be solved in the linear approximation.
Dedicated to the Memory of M.S. Molodensky
Contribution to the I.A.G. Special Commission SC3 Fundamental Constants (SCFC). 相似文献
144.
本文概述了弹性地球负荷潮汐应变的理论,研究了计算负荷勒甫数的递推算法,并对处理褶积积分的基本方法及过程作了讨论,给出了有关的工作公式。 相似文献
145.
146.
杨学祥 《吉林大学学报(地球科学版)》1987,(3)
严格地说,地球是一个三轴椭球体。由k=2的近似计算公式,可以得到精确数字为8位的地球表面积数值。三轴椭球体表面积公式建立了地球三个半轴与地表面积之间的函数关系。对于已测得的三个半轴的任何微小变化,由微分近似计算公式可以得到相应的地表面积的变化。这就为研究地球形变和地壳运动之间的关系提供了一个数量化的有力工具。 相似文献
147.
148.
运用岩石破裂过程分析RFPA2D系统,研究了岩石介质细观非均匀性对宏观力学行为的影响和微震序列特征. 通过对不同均质度系数m=1.1,1.5,2,3,5的5个样本进行破裂过程的模拟,发现均质度不同会产生不同地震序列类型,主要有:前震-主震-余震型、主震型和震群型. 此外,对5种不同均质度系数的岩石样本破裂过程的模拟表明,岩石介质的非均匀性不仅对岩样宏观强度和宏观变形非线性行为有显著的影响,而且也显著地影响试样破裂模式. 随着均质度系数的提高,主破裂呈现脆断模式. 同时介质的细观结构随机性,也对试样宏观破裂模式产生重要影响. 相似文献
149.
Quartz microstructures developed during non-steady state plastic flow at rapidly decaying stress and strain rate 总被引:7,自引:0,他引:7
Synseismic loading to very high stresses (>0.5 GPa) and subsequent creep during stress relaxation in the uppermost plastosphere at temperatures of ca. 300–350 °C, near the lower tip of an inferred once seismically active crustal scale fault, was proposed based on peculiar microstructures identified in rocks exposed over >100 km2 in the Sesia Zone, European Western Alps. Here we discuss the conspicuous and highly heterogeneous microstructural record of quartz in disseminated small-scale shear zones. Sub-basal deformation lamellae and arrays of elongate subgrains on the TEM-scale indicate an early stage of glide-controlled deformation at high stresses. Distributed brittle failure is indicated by healed microcracks. Very fine-grained recrystallised aggregates with a pronounced crystallographic preferred orientation reflect intense plastic flow by dislocation creep. Locally, a fine-grained foam microstructure indicates a final stage of static grain growth at low differential stress. For the previously inferred peak stresses of about 0.5 GPa and given temperatures, initial strain rates on the order of 10−10 s−1 are predicted by available flow laws for dislocation creep of quartz. We emphasise the importance of short-term non-steady state deformation in the uppermost plastosphere underlying seismically active upper crust. The related heterogeneous record of quartz is governed by the local stress history at constant temperature. 相似文献
150.
Dynamic causes for the opening of the Baikal Rift Zone: a numerical modelling approach 总被引:1,自引:0,他引:1
Previous dynamic models of the Baikal Rift Zone (BRZ) are mostly two-dimensional on vertical plane. In this study, a numerical model of neotectonics in the region on map view was constructed using the adapted PLATES program. The present work is an attempt to test different mechanisms for opening Baikal Rift by comparing the modelled and observed stress and strain rate fields. The following rifting scenarios were tested: (1) pure northwest–southeast extension, (2) pure northeast–southwest compression, (3) oblique rift opening and (4) combined northwest–southeast extension and northeast–southwest compression. The models are calibrated using geologically and GPS-derived strain rates and stress-tensor determinations from fault-slip data and earthquake focal mechanisms. The most successful model requires a combination of NE–SW compression and orthogonal extension. The model results indicate that the present extensional regime in BRZ can be explained by combining the India plate indentation northward into Eurasia, east–west convergence between the North America and Eurasia plates and southeastward extrusion of the Amur plate in northeastern Asia. Predicted fault-slip rates for the best-fit model are consistent with the observed Holocene fault-slip rates in the Lake Baikal region. The generally accepted rotation of the Amur and Mongolia microplates are used as independent constraints for the choice of the best-fit model. These data correlate well with the predicted direction of rotation in our best model. 相似文献