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711.
Zhende GUAN Chen CHEN Jian ZHANG Miao WANG College of Construction Engineering Jilin University Changchun China 《东北亚地学研究》2008,11(2):88-92
A conceptual model called virtual borehole is presented in practice engineering. Based on borehole data and the geologic section and by using GMS 6.0, MAPGIS software, the 3D stratum model of urban geologic information is established. The visual expression and analysis of 3D geologic data can be better realized in the open model established. 相似文献
712.
Zhiguo MENG Shengbo CHEN Cai LIU Xiaojuan DU Tao MENG Zijun WANG Hang LU College of Geoexploration Science Technology Jilin University Changchun China 《东北亚地学研究》2008,11(2):102-109
It is one of the imPortant methods to retrieve lunar regolith thickness using active and passive microwave techniques. The retrieval of lunar regolith thickness is based on microwave radiation transfer process simulation in the regolith media. The lunar regolith model is first introduced, and the features of the involved physical parameters are indicated thereafter, such as dielectric constants, surface roughness, particle size and thermal grads of the lunar regolith. The time delay and the migration of the radar echoes from the different interfaces is the key problem for active microwave measurement. And the simulation of the microwave radiative transfer in the regolith media is the important technique for the passive microwave measurement. The important parameters and the physical mechanism for the two measurements are also presented. 相似文献
713.
Peiping ZHANG Shufeng LIU Xuefa SHI Huahua LU Juanjuan LIU Xiaoguo CHI.College of Earth Sciences Jilin University Changchun China 《东北亚地学研究》2008,11(2):110-114
To make use of the pelagic clay as polymer filling, the properties of clay sediments from the ocean investigation zone of China in the East Pacific were studied by the SSA, XRF, ICP/MAS, FTIR, XRD, SEM, DTA/TG and granularity distributing etc. , and experiments were settled to improve the whiteness and activation of the clay based on these data. Compared with land clay, pelagic clay holds many particular features, such as fine particles and incompact accumulation, worse crystallization and more defects, high activity, complex mineral and chemical components, and low whiteness etc. Processing the purified pelagic clay with acids and zinc, then baked it at different temperatures, the whiteness of clay can be increased from 23.8% to 73.1%, and the optimized conditions is: consistency of vitriol 25%, ratio of clay to water 4: 1, reaction time 4h, reaction temperature 90℃, dosage of zinc 2.0 g/L, and baking temperature 700℃. And the SSA of whited clay is increased too. Using the dry milling method to modify the pelagic clay with organic reagents, the optimized technique is KH550, concentration 1.5%, reaction time 20 min. XRD, FTIR and SEM testing indicate that the mechanism of organic activation was mainly surface absorbing and chemical combination secondly. 相似文献
714.
Conodont samples were collected from three localities in the Onoo Tolgoi area, Mongolia, and many conodonts have been found. Conodonts from the Onoo Tolgoi Formation (M288-M294) lack index fossils; its age could be Late Silurian. Samples from the Hutul us hudag Formation (M295-M299) contain Ozarkodina pandora alpha Morph. ( P element), clearly indicating that this formation is Early Devonian late Lochkovian in age. Samples collected from so-called Silurian Onoo Tolgoi Formation at other localities (M300-M303) yield many Ordovician conodonts, including Icriodella baotaensis, Icriodella cf. baotaensis, Eoplacognathus fianyeen- sis, Eoplacognathus protoramosus ; Baltoniodus alobatus ; and ? Ambalodus triangularis ; the age is Late Ordovician, more precisely, early-middle Late Ordovician. 相似文献
715.
Li YU Zhaohua YANG Yingyu JIN Li ZHANG Construction Engineering College Jilin University Changchun China 《东北亚地学研究》2008,11(4):242-245
Based on the theory of elastic mechanics, and using the typical rupture model of shallow earthquake, the authors considered the shallow earthquake as a plane mechanical problem, which was constructed the corresponding mechanical model. By the stress components' formulas of the semi-infinite model acted by the finite even shearing force, the main stress is deduced. It is clear that the sector on the right of the center section is squeezed zone, where the maximum principal stress points at the "source of stress", and that on the left is tensile zone, where the minimum principal stress points to the "source of stress". 相似文献
716.
Xianwei ZHANG Changming WANG Junxia LI Bin WANG College of Construction Engineering Jilin University Changchun China 《东北亚地学研究》2008,11(4):251-255
Pore water pressure has an important influence on mechanical properties of soil. The authors studied the characteristics of pore water pressure dissipating of mucky soil under consolidated-drained condition by using refitted triaxial instrument and analyzed the variation of pore pressure coefficient with consolidation pressure. The results show that the dissipating of pore water pressure behaves in different ways depends on different styles of loading. What is more, the pore water pressure coefficient of mucky soil is less than 1. As the compactness of soil increases and moisture content reduces, the value of B reduces. There is a staggered dissipating in the process of consolidation, in which it is a mutate point when U/P is 80%. It is helpful to establish the pore water pressure model and study the strength-deformation of soil in process of consolidation. 相似文献
717.
Chang LIU Shouyi LI Jian GUAN Tingting ZHANG Ying CHU Jing ZHANG . College of Earth Sciences Jilin University Changchun China. English Department Jilin Agricultural University Changchun China 《东北亚地学研究》2008,11(3):150-155
northeastern China is an important old industrial base in China. Mineral resources are the foundation of industry development. However, because of long-term exploitation of mineral resources in northeastern China, the mineral resources reserves decrease gradually and some mineral resources are nearly exhausted, which restricts revitalization and sustainable development of the northeast old industrial base. On the basis of the comprehensive analysis of development and utilization status of mineral resources and supply and demand situation of main mineral resources in northeastern China, the authors put forward countermeasures on main mineral resources sustainable supply in northeastern China. 相似文献
718.
719.
ZHOU Lincong ZHENG Yifeng PAN Shunchun. College of Construction Engineering Jilin University Changchun China . Jiaozhou Urban Planning Bureau Jiaozhou Sh ong China 《东北亚地学研究》2009,(3):168-173
It is considered thai the damage of the underground structures caused by earthquakes is minor for a long time. However, the catastrophic damages induced by several recent earthquakes (e. g. Kobe earthquake in 1995 ) revealed that the study on the dynamic properties of the underground structures is indispensable. The dynamic behavior and damage mechanism of underground structure are analyzed by using shaking table tests ( both shallow-and deep-buried) and numerical simulation (3D FEM) including horizontal and vertical input motions, individually and simultaneously. From the results, the underground structure collapsed due to strong horizontal forces although vertical deformation is not negligible. The vertical excitation increases the response of structure, especially the stress and shear stress at the upper section; the soil influenced the property of soilstructure system. In the same excitation, the response in shallow-buried test is larger than deep case. Both overburden and vertical earthquake play important roles in the response of structure and those are two critical aspects in the design of the large-span underground structures, such as subway stations. 相似文献
720.
HUANG Zhiquan WANG Gangcheng ZHANG Guojun.College of Construction Engineering Jilin University Changchun China.Liaoning Electric Power Survey Design Institute Shenyang China 《东北亚地学研究》2009,12(2):112-116
Clogging effect, as a new concept in geological engineering, is a phenomenon of permeability decreasing under seeping in reservoir dam foundation of the alluvial and diluvial deposits with deep and thick layer, coarse particle and high permeability in mountains-gully rivers of Tibetan Plateau. A clogging infiltration instrument has been designed successfully and a series of simulation tests have been done. Based on large amounts of data, it is confirmed that the existence of the clogging effect and the law of infiltration clogging is found out. Three indexes are proposed such as "optimal size of particle", "optimal size range of particle" and "characteristic pore", which are closely related with effect of infiltration clogging. The concept and results can offer a new idea to solve problems on anti-seepage of dam foundation in mountains-gully rivers environment and to study artificial clogging, meanwhile supplement of the concept of seepage deformation. 相似文献