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1.
Hoek-Brown岩体强度估算新方法及其工程应用   总被引:3,自引:0,他引:3  
如何利用现场调查和室内试验来估算工程岩体强度参数一直是众多工程技术人员要解决的难点问题,而Hoek-Brown强度准则为此提供了一条良好的途径。文中详细介绍了Hoek-Brown强度准则的由来、发展反目前的发展现状和应用状况,并介绍了最新的Hoek-Brown强度准则和岩体强度估算方法的内容。最后笔者结合国内的一个大型水电工程,详细介绍了其应用和效果。说明该方法完全解决了工程岩体强度参数估算的问题,而且效果电好,有着广泛的应用前景。  相似文献   

2.
岩石,混凝土强度理论:历史,现况,发展   总被引:6,自引:0,他引:6  
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3.
介绍了混凝土抗压强度和抗折强度试件的制作过程、养生方法,论述了混凝土强度的测定、计算的方法和标准。  相似文献   

4.
周上然 《科技信息》2012,(28):454-454
船舶在设计建造及使用过程中无时无刻不在受力,研究船体结构受力,用来指导船舶的建造及日后的航行使用。本文着重介绍了船体强度(总体强度与局部强度)的研究现状及它对船舶建造和航行的影响,在船舶的建造过程中应该以强度为主导,优化结构设计,使其合理分布受力。在船舶航行的过程中,根据船体自身的强度,调整航行性能,保证安全。  相似文献   

5.
大型油船的剪切强度校核   总被引:1,自引:0,他引:1  
阐述双壳体、具有中纵舱壁的大型油船重点实施剪切强度校核的部位和校核的方法以及剪力修正的计算公式.通过选取一艘大型油船剪切强度校核的实例,说明在大型油船装载和卸载中应该注意隔舱装载可能对船体强度造成的损害.为编制大型油船的装卸载工艺提供相应的数据.  相似文献   

6.
形变硬化指数与强度的关系   总被引:14,自引:1,他引:14  
从硬化指数的定义出发导出了形变硬化指数n与强度参量之间的关系为n=A(1-σⅠ-/σⅡ)+B,σⅠ和σⅡ为真应力应变曲线上一直线段两端点的应用力,A和B为常数,它适用于单一n值情况,双n特性,单调加载和循环应力应弯曲线,对均匀变形阶段,又导出了n和屈强比的关系,即n=1-√σs/σb,该式没有任何特定常数和经验常数,和测量值相比90%以上的数据的绝对误差在±0.03以内,它表示了材料的均匀变形能力  相似文献   

7.
假定混凝土总体强度呈正态分布,通过概率统计基本知识和抽样检验理论建立了混凝土施工配制强度与抽样检验方案及混凝土验收强度之间关系的不等式方程组,由此找到了一种确定混凝土配制强度的更合理的方法。  相似文献   

8.
混凝土结构的质量控制有众多的措施,其中强度的检测方法尤为重要。文章在对国内外常规检测方法比较分析的基础上,提出了合理化建议。  相似文献   

9.
卸荷土体的强度特征   总被引:3,自引:0,他引:3  
从理论及试验两方面研究了卸荷土体抗剪强度的问题,分析了土体卸荷与加荷两种受力状态下的不同强度特征,建议以加卸荷强度路径试验曲线线为依据进行卸荷计算。  相似文献   

10.
本文阐述了新老砼结构规范中砼“标号”和“强度等级”的区别,并对新规范中的砼强度评定方法进行了详细论述  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
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