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21.
考虑入渗和蒸发影响的土坡稳定性分析方法 总被引:47,自引:7,他引:47
本研究建议的一种分析方法假定斜坡非饱和土体的水分运动参数及剪强度参数与饱和度的依赖关系均可根据实验或经验确定。通过数值计算方法妥任意给定的入渗和蒸发边界条件下斜坡土体的瞬态含水率分布及与其相对应的瞬态抗剪强度参数分布。在此基础上瞬态斜坡安全因数即可通过常规的稳定性分析方法求得。 相似文献
22.
Bi Fuzhi Yuan Youshen Institute of Crustal Dynamics State Seismological Bureau Beijing 《《地质学报》英文版》1997,71(4):395-406
This paper expounds the quantitative tectonic indicators and some qualitative indicators of large earthquakes in the coast areas of Fujian, Guangdong, Taiwan and Hainan. The main quantitative indicators include uplift amplitude of the Moho, Quaternary and Late Holocene coasts. The paper also gives a brief account of the research method on quantitative indicators of surface uplifted zones. Taiwan is a famous neotectonic zone and an area of large earthquakes in the world. There is only one large-earthquake area in each of Fujian, Guangdong and Hainan Provinces. Along the coast large earthquake areas there are certainly many remains of crustal activity. Among these remains, coast activity, taking the sea level as the accurate marker horizon, can determine not only the amplitude of coastal elevation and subsidence in a certain period, but also the cycle and rate of positive or negative movements. 相似文献
23.
Hu Yi-li Xu Jun Duan Yong-kong Xu Zhao-yong Yang Run-hai Zhao Jin-ming 《地震学报(英文版)》2004,17(6):725-734
A new method of detecting the vertical bearing capacity for single-pile with high strain is discussed in this paper. A heavy
hammer or a small type of rocket is used to strike the pile top and the detectors are used to record vibration graphs. An
expression of higher degree of strain (deformation force) is introduced. It is testified theoretically that the displacement,
velocity and acceleration cannot be obtained by simple integral acceleration and differential velocity when long displacement
and high strain exist, namely when the pile phase generates a whole slip relative to the soil body. That is to say that there
are non-linear relations between them. It is educed accordingly that the force P and displacement S are calculated from the amplitude of wave train and (dynamic) P-S curve is drew so as to determine the yield points. Further, a method of determining the vertical bearing capacity for single-pile
is discussed. A static load test is utilized to check the result of dynamic test and determine the correlative constants of
dynamic-static P(Q)-S curve.
Foundation item: Key projects of the tenth Five-year Plan of Yunnan Province (documented Yunnan district [2002]54-02-02) and Geophysical
Society of Yunnan Province. 相似文献
24.
地貌单位线(GIUH)基于流域地貌特征和概率方法,在我国许多地区得到广泛应用。针对面雨量分布不均问题,通过分析初始概率的变化,考虑GIUH的非线性改正,并用实际资料进行了验证。 相似文献
25.
苏里格庙气田主要产气层为上古生界石盒子组盒8段,属于三角洲平原分流河道沉积。复合砂体近南北向展布;单砂体的厚度变化大,非均质性明显,储渗变化大。盒8段含气砂岩在AVO资料上有明显反映;在综合测井资料上,盒8段表现出自然伽玛测井值、密度测井值、补偿中子测井值都偏低,电阻率、声波时差测井值较高,出现了大幅度的自然电位异常。利用核磁共振测井技术测得苏里格庙区某井盒8段3555.9m~3559.6m为气层,3560.6m~3572m为气水层,与生产实践吻合得很好。 相似文献
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Introduction The 21st century is the time for the exploitation and utilization of underground spaces. It is astrategic way to defeat the severe challenge that human are now confronting with, such as the lackof land, contamination of environment, traffic jam, waste of sources, and so on. The exploitationand utilization of underground space has become a global tendency, and a significant sign inevaluating the speed of modernization of cities. Facing the challenge, it is significantly necess… 相似文献
28.
2001年,广州海洋地质调查局对“探宝号”船原有震源更新升级为阵列可变的BOLT震源系统。随着更新改造工程的成功,该船已成为具备承担高分辨率、常规、低频深水油气地震勘探的多功能地震调查船。本文介绍了地震勘探震源的基本工作原理以及三种阵列的分布、波形、频谱等特性。 相似文献
29.
30.
ABSTRACTA novel approach is introduced for simulation of instantaneous unit hydrographs (IUHs). The model consists of a series of linear reservoirs that are connected to each other, and is referred to as the inter-connected linear reservoir model (ICLRM). By assuming the flow between two reservoirs is a linear function of the difference between the water levels in the reservoirs, a system of first-order linear differential equations is obtained as the ICLRM governing equation. By solving the equations, the discharge from the last reservoir is considered as an IUH. A small-scale laboratory device was constructed for the simulation of IUHs using the model. By studying four hydrographs extracted from the literature, and simulating them using both the ICLRM and the Nash model, it is concluded that the ICLRM can predict these hydrographs more accurately than the Nash model. Due to the simplicity of the construction and operation of the ICLRM and, more importantly, its visual aspect, the ICLRM may be considered as an effective educational tool for studying IUHs. 相似文献