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11.
Influence of Structural Non-Stationarity of Surface Roughness on Morphological Characterization and Mechanical Deformation of Rock Joints 总被引:2,自引:2,他引:0
N. Fardin 《Rock Mechanics and Rock Engineering》2008,41(2):267-297
Summary Structural non-stationarity of surface roughness affects accurate morphological characterization as well as mechanical behaviour
of rock joints at the laboratory scale using samples with a size below the stationarity threshold. In this paper, the effect
of structural non-stationarity of surface roughness is investigated by studying the scale dependence of surface roughness
and mechanical behaviour of rock joints. The results show that the structural non-stationarity mainly affects the accurate
characterization of the surface roughness of the fracture samples. It also controls the amount and location of the contact
areas during shear tests, which in turn affects the mechanical properties and asperity degradation of the samples. It is concluded
that for accurate determination of the morphological and mechanical properties of rock joints at laboratory and field scales,
samples with size equal to or larger than the stationarity threshold are required.
Author’s address: Nader Fardin, Rock Mechanics Group, Department of Mining Engineering, Faculty of Engineering, University
of Tehran, P.O. Box: 11365/4563, Tehran, Iran 相似文献
12.
在柴达木盆地北缘地区,分别选取有机碳含量很低和较高的侏罗系泥岩样品,对比分析了它们在生物标志物组成上的差异。结果发现,高有机质丰度泥岩的生标组成与我国西北地区侏罗纪煤系有机质的特征差异不大,相比而言,低有机质丰度泥岩的正烷烃以前主峰为特征,Pr/Ph比值在1.0左右,三环萜烷和伽马蜡烷丰度较高,并在部分样品中检出了25 降藿烷系列。结合泥岩的有机岩石学特征,认为这些差异可能反映了泥岩沉积环境和生烃母质的不同:高有机质丰度泥岩的有机显微组分以相对弱还原条件下的形态有机质为主,包括藻类体、孢子体和角质体等,而低有机质丰度泥岩的有机显微组分以相对强还原条件下的矿物沥青基质为主,其母质可能来源于低等显微菌藻类。进一步通过对比不同有机质丰度泥岩,以及区内原油生标组成之间的相互关系,讨论了研究区的油源问题。 相似文献
13.
利用野外资料、地震资料、煤田钻孔资料以及古生物资料,对松辽盆地外围探区敦化盆地的代表性地层划分方案进行了梳理,通过敦化盆地与周缘盆地之间的对比和分析,得出下列认识:(1)明确了珲春组的时代为始新世—渐新世;(2)指出白垩系上统龙井组地层在敦化盆地内可能是不存在的;(3)将原帽儿山组上段和下段分别划归泉水村组和长财组;(4)认为大砬子组、泉水村组、长财组和屯田营组在敦化盆地内是存在的,并通过盆间岩性地层和古生物地层对比指出大砬子组的时代可能为早白垩世阿普特期(Aptian)—阿尔布期(Albian),长财组时代可能为早白垩世贝利阿斯期—阿普特期;(5)对敦化盆地内几个地方地层名称的使用进行了修正;(6)建立了敦化盆地内目前可供参考使用的地层序列。 相似文献
14.
Toru?Iwata Keiko?Yoshikawa Katsutoshi?Nishimura Yoshihisa?Higuchi Takao?Yamashita Shigeru?Kato Eiji?OhtakiEmail author 《Journal of Oceanography》2004,60(6):995-1000
The measurements of the vertical transport of CO2 were carried out over the Sea of Japan using the specially designed pier of Kyoto University on September 20 to 22, 2000. CO2 fluxes were measured by the eddy correlation and aerodynamic techniques. Both techniques showed comparable CO2 fluxes during sea breeze conditions: −0.001 to −0.08 mg m−2s−1 with the mean of −0.05 mg m−2s−1. This means that the measuring site satisfies the fetch requirement for meteorological observations under sea breeze conditions. Moreover, the eddy diffusivity coefficient used in the aerodynamic technique is found to be consistent with the coefficient used in the eddy correlation technique. The present result leads us to conclude that the aerodynamic technique may be applicable to underway CO2 flux measurements over the ocean and may be used in place of the bulk technique. The important point is the need to maintain a measuring accuracy of CO2 concentration difference of the order of 0.1 ppmv on the research vessels or the buoys. 相似文献
15.
本文报道了1987年夏、冬两个航次在26°50′~32°30′N,124°30′~131°30′E海区中可溶性无机磷酸盐的调查结果,阐明了磷的分布特征和形成机制。结果表明陆架区表层测值较高,大洋区为低值区,底层则相反。大洋水常年分层,中层水有爬坡涌升现象,其浓度与Aou呈正相关,与pH和S呈负相关。夏、冬两季底层磷与Aou呈正相关,其浓度变化主要依赖于生物过程。 相似文献
16.
The probability of fractal determination of coastal types based on GIS is preliminarily discussed with China as an example. Finally, some significant conclusions are drawn: (1) The fractal dimension of coastline of the bedrock coast is larger than that of the plain coast on the same scale map; (2) As far as the bedrock coast is concerned, the larger fractal dimension of coastline of the bedrock coast on the same scale map indicates that the bedrock coast is probably not typical; (3) As far as the plain coast is concerned, the smaller fractal dimension of coastline of the plain coast on the same scale map indicates that it is probably the silt plain coast; (4) The different substantial compositions affect the fractal dimensions of coastlines of different coastal types. In general, the coast which lies in the north of the Hangzhou Bay consists of sand mainly, its surface is flat, and it is connected with the coastal plain, its landform is broad shoal, its total change is comparatively homogenous in the tidal dynamic process, and thus, the relatively smaller fractal dimension of coastline results from this. For the bedrock coast, there is more bedrock, the coastline is comparatively smooth and straight, being affected by the faults and ocean dynamic process, which result in the larger fractal dimension. 相似文献
17.
根据大量田间试验和调查资料分析,作者提出烟单14号玉米生长过程中,小喇叭口期土壤中全氮、大喇叭口期土壤中速效磷的含量与产量相关密切。并据此建立了产量及构成三因素与土壤养分间的最优相关模型。 相似文献
18.
富钴结壳分布的分形特征 总被引:8,自引:0,他引:8
何高文 《海洋地质与第四纪地质》2001,21(1):89-92
利用我国在西太平洋国际海底两个海山获得的富钴结壳资料进行分形研究后发现,富钴结壳的分布具有变维分形分布的特点,结壳丰度呈二阶累计和分形分布,结壳厚度呈多阶不定累计和分形分布,通过计算得到了它们各自的分维数,进而对两个海山的结壳资源进行了初步评价。 相似文献
19.
通过对东京湾两年度不同季节海水分光反射率与叶绿素浓度进行统计分析,结果表明,叶绿素浓度C与两谱段分光反射率之比Rw(λj)/Rw(λj)具有幂函关系C=A[Rw(λj)/Rw(λj)B。两者的对数显示出较好的线性关系,即logC=logA+Blog[Rw(λj)/Rw(λj)]。负相关系数达0.99。相关方程之一为C=3.329[Rw(520)/Rw(550)]-1.384(1987年6月初).在梅雨季节之后,相关方程为C=12.68[Rw(520)/Rw(550)]-2.010(1988年8月)。这表明了海湾或混浊的沿岸水质,在叶绿素浓度算法中,统计参数A和B的确立,要基于不同季节不同水质的现场观测资料。 相似文献
20.
Fractal Dimension and Fractals in Ocean Engineering 总被引:4,自引:0,他引:4
Fu Yuhua Senior Engineer China Offshore Oil Engineering Corporation P. O. Box Beijing 《中国海洋工程》1994,(3)
- This paper discusses the application of fractal dimension and fractals in ocean engineering. To handle some ocean environment problems, the existing fractal method, in which the fractal dimension is a constant, can be used. For some complicated problems in ocean engineering, this paper presents the concept of the variable dimension fractals (D = f(r)), i. e., the fractal dimension D is the function of characteristic scale r instead of a constant. By using variable dimension fractals, several deformation and stress states of offshore structures are described. 相似文献