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1.
结合齐齐哈尔市卜奎清真寺西寺正殿的结构特点,对其抗震机理进行了探讨。并依据现行抗震设计理论及相关规范对西寺正殿主要构件的截面抗震承载力进行验算,结果表明其截面承载力满足6度抗震设防要求。  相似文献   

2.
通过对砖混结构教学楼的抗震加固设计进行研究,得到进行抗震加固时,首先对其进行抗震承载力分析,通过建模及验算得到Push-over曲线及地震反应谱曲线,根据这些曲线再对教学楼进行详细的分析,最后根据所有分析结果提出相应的加固设计,提高教学楼的抗震承载力,确保师生的生命财产安全.  相似文献   

3.
根据试验测定的不同循环次数下的海水侵蚀混凝土梁斜截面承载力,建立毫非线性的渐近回归分析模型,并采用遗传算法进行参数的优化计算,然后根据模型计算混凝土梁斜截面承载力,其结果与实测数据吻合较好,混凝土梁斜截面承载力计算值的平均相对精度在95%以上。因此,基于遗传算法的非线性回归模型可以用于海水侵蚀混凝土梁斜截面承载力的分析。最后,实现了混凝土梁斜截面承载力分析的智能化。  相似文献   

4.
对旧有教学楼改造工程进行研究.通过结构计算和分析,采用预应力加固的方法,降低框架梁支座负弯矩;对框架梁正弯矩部分进行粘钢补强;对框架柱采用角部通长增设角钢的加固方式提高正截面承载力,并采用焊接钢箍提高其抗剪承载力.加固后,建筑物的抗震性能得到了显著提高.  相似文献   

5.
运用ABAQUS有限元分析软件对预应力离心钢管混凝土管桩(PSC桩)进行抗震性能有限元分析,根据有限元模拟结果对其破坏特征、滞回曲线以及骨架曲线进行初步分析,并通过改变钢管壁厚、混凝土壁厚以及预应力筋配筋率,分析其对抗震承载力的影响。结果表明,PSC桩破坏表现出明显的塑性特征,滞回曲线呈梭形,形状饱满,耗能能力好;随着钢管壁厚的增加,PSC桩的抗震承载力增加较为明显,随着预应力筋配筋率的增加,抗震承载力有一定程度提高,混凝土壁厚对PSC桩抗震承载力几乎没有影响.  相似文献   

6.
为研究工字形截面钢管混凝土边框钢板组合剪力墙的抗震性能,进行了3个试件在轴向压力和水平往复荷载作用下的低周反复荷载试验,分析了腹板墙体内藏单钢板、内藏单钢板及钢筋暗撑、外包双钢板等不同构造对其抗震性能的影响.试验研究表明:设置钢筋暗撑可提高工字形截面钢管混凝土边框内藏钢板组合剪力墙的承载力、变形和耗能能力,但用钢量相对较大;将内藏钢板及分布钢筋等含钢率转换为外包双钢板后,其承载力、刚度有所降低,但变形能力有较大增强;工字形截面钢管混凝土边框钢板组合剪力墙具有良好的屈服机制和多道抗震防线,适用于高层及超高层建筑抗震设计.  相似文献   

7.
为寻求一种较为简单的方法,计算钢骨混凝土柱的正截面强度,对钢筋混凝土部分和钢骨部分所承担的轴力大小进行了分析,根据冶金工业总公司结构设计标准中的正截面承载力计算公式,提出了一种新的轴向力分配方法,该方法根据钢骨混凝土柱在轴心受力状态下,钢骨部分与钢筋混凝土所处的状态来分配轴向荷载,然后根据现有规范来计算两部分的承载力,其和即为钢骨混凝土柱的正截面强度。该方法使得钢骨混凝土柱正截面承载力计算方法概念明确,计算简单,并与试验结果吻合较好  相似文献   

8.
为了考虑高阶振型对输电塔抗震性能的影响,结合振型侧向力组合方法(MLFC)和能力谱法提出了该类结构的抗震性能评估方法。首先根据输电塔的振型贡献系数识别主要贡献振型,然后考虑各振型侧向力的加权正负组合构建基于MLFC的侧向力组合模式,并采用能力谱法分析确定输电塔的能力曲线和性能指标,最后根据输电塔的抗震性能目标和顶部位移性能水准进行抗震性能评估,从而建立了考虑高阶振型影响的输电塔抗震性能评估方法。结合工程实例分析表明,基于MLFC的侧向力组合模式在抗震能力曲线和位移性能指标分析方面与增量时程分析法吻合较好,能够有效地考虑高阶振型对输电塔抗震性能的影响。  相似文献   

9.
钢筋混凝土异形柱轴压比限值研究   总被引:16,自引:0,他引:16  
根据《混凝土结构设计规范》关于正截面承载力计算原理,对L形、T形和十字形截面柱的轴压比限值进行了数值计算分析,得出了不同截面形状、不同纵向配筋率和不同和轴角度时的轴压比限值随含箍特征值的变化规律。提出对于T形柱和L形柱,目前按规范规定的轴压比限值或广东省标准规定的轴压比限值进行异形柱抗震设计,是偏于不安全的;按天津市标准进行异形柱抗震设计,其可靠度需进一步研究。十字形截面柱配筋基本均匀布置,平衡破坏时轴压比较矩形截面情形略有提高,采用规范规定的矩形柱轴压比限值是可行的,并且柱的延性比矩形柱的有所提高。  相似文献   

10.
以某独塔自锚式悬索桥为工程背景,采用空间有限元程序ANSYS,对其进行了地震反应仿真计算.针对桥塔和桥墩为异形结构(贝壳状弧形壳体),采用8节点实体单元模拟主塔和桥墩.通过迭代计算确定结构初始平衡状态并计入初应力对结构刚度的影响,建立了全桥精细有限元模型.分别对嵌固模型、考虑桩-土相互作用和考虑承台土压力这3种模型进行了不同地震波组合下的动力时程反应分析.计算结果表明:塔根截面的应力水平最高,是结构抗震的关键部位;墩和塔出现了局部应力集中的现象,应力集中的区域在截面突变处和截面的角点处;考虑承台土压力的影响,可以有效减小桩基础的应力;精细有限元模型可以较好地反映结构在地震作用下的易损部位.  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.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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