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1.
钢纤维膨胀混凝土管状构件受拉应力-应变全曲线研究   总被引:6,自引:0,他引:6  
成功地测出了钢纤维膨胀混凝土管状试件轴拉应力-应变全过程曲线,并应用微裂缝开展理论,对全过程曲线作了宏观过程和微观机理分析,在试验基础上,对钢纤维膨胀混凝土管状试件受拉应力-应变全曲线进行了数值模拟,给出了与试验结果符合较好的模拟方程。  相似文献   

2.
孙平  王蕴珊 《山东科学》1995,8(4):32-34
应用偏振的剪切散斑干涉技术,对有预制裂纹的铜钢双材料试件进行了实验研究,给出了实验结果,直接得到了裂纹处的全场应变纹。  相似文献   

3.
本文讨论了局部加热法的原理和影响因素,介绍了小型导热仪的结构,给出了对几种不良导热材料的测试结果。试验表明,局部加热法设备简单,可对试件进行现场及非破坏性测量,测量结果与文献报导基本相符。  相似文献   

4.
分离式Hopkinson拉杆是当前进行材料高应变率加载条件下力学行为的主要研究手段.受加载条件的限制,往往采用小尺寸的试件开展实验.因此,试件在加工过程中的加工硬化对实验结果会产生一定的影响,从而不能完全反映真实材料的力学性能.为研究这一效应的影响,首先利用微纳米压痕法测量了小尺寸不锈钢试件沿表面厚度方向的维氏硬度变化规律,得到了加工硬化层的厚度及其对材料性能的影响.在此基础上,通过理论分析研究了加工硬化对试件拉伸试验结果的影响,并结合不同尺寸试件的准静态拉伸试验结果,给出了分离式Hopkinson拉杆动态拉伸结果的修正方法.  相似文献   

5.
混凝土拉伸应力—应变全曲线实验测定的条件   总被引:2,自引:0,他引:2  
对影响实验测定混凝土应力-应变全曲线的主要因素作了探讨,除分析了试验机的测试影响外,还特别讨论了试件尺寸对试验结果的影响,提出了实验测试稳定的拉伸应力-应变全曲线必须具备的前提条件。  相似文献   

6.
考虑加载历史影响的蠕变试验数据整理方法   总被引:1,自引:0,他引:1  
本文根据页岩多级循环单轴压缩蠕变试验所得的数据,分析研究了加载历史对岩石试件变形的影响,提出了一种考虑这种影响的多级循环蠕变试验数据的整理方法。用该法整理出来的结果,比较真实地反映了岩石试件本身的流变力学行为,从而有助于建立岩石的本构方程。这种方法可供对粘弹塑性岩石进行多级循环蠕变试验时整理所得到的试验数据之用。  相似文献   

7.
应用自制的真三轴拉压刚性试验机,结合高拱坝水工混凝土的受力特点,采用立方体试件进行双轴拉压受力试验。根据试验结果,分析了试件的破坏形态、应力应变全曲线和拉压强度,并给出相应的全曲线方程和强度计算公式。  相似文献   

8.
为了确定弯曲力矩对EFPI光纤传感器输出的影响,制作了将光纤传感器埋入其中间层的复合板试件,并对试件进行三点弯曲试验,得到了弯曲力矩与光纤传感器输出应变之间的关系。随后,用显微镜对复合板的横截面进行观察,确定光纤传感器的埋入位置。对光纤传感器的埋入位置偏离复合板中间层的试件,运用有限元应变分析法(FEM)计算其应变值。实验结果表明,当光纤传感器的埋入位置偏离复合板中间层时,光纤传感器的应变大于计算值,说明弯曲力矩影响光纤传感器的测试性能。  相似文献   

9.
蒸发式冷却器的传热传质试验研究   总被引:5,自引:0,他引:5  
对蒸发式冷却器传热传质试验结果的数据处理进行了讨论,重点是它的容积散质系数以及工艺水到水膜的传热系数.介绍了试验台和各测试仪表,给出了对两个试件的测试结果,整理了βxv和K的变化规律,并与计算结果作了分析对比  相似文献   

10.
对纯铜光滑试件和缺口试件的疲劳寿命规律差异进行探讨。通过光滑试件和缺口试件的循环疲劳试验和缺口试件的局部循环弹塑性应力应变响应分析,结合数值模拟与实验,比较了现有寿命预测方法对缺口试件寿命预测结果的差异。研究结果表明:传统的等应变幅等寿命的概念对于缺口试件的疲劳评估是不合理的;局部应力应变法用于大缺口试件的寿命预测结果可得到基本合理的结果;但对小缺口试件估测寿命结果不合理;应力梯度法对缺口试件寿命估测结果较局部应力应变法合理,因此可认为应力梯度是影响光滑和缺口试件疲劳寿命差异的重要因素。  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 Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
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   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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