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1.
由于大柱距的工业厂房有利于工艺流程的合理布置,并能节省柱子的占地面积,而工业厂房又离不开起重设备,因此,大跨度的钢吊车梁设计越来越频繁地出现在设计者面前。鉴于目前钢吊车梁标准图只有12米柱距的,且都是以老规范为依据,已满足不了设计要求。另外,在设计工业厂房时,往往要在吊车梁上增加平台  相似文献   

2.
某厂房因用途变化,在顶层增设一层作配电室用,为此需在原有楼面上对梁、板、柱进行加固,采用置换受压区混凝土并增设暗梁形成锚固键的方法加固楼板;加大截面法加固楼面梁。这些作法工艺简单,操作方便,经济节约,且可靠性好。  相似文献   

3.
某单层化工厂房使用时间已达50余年,使用过程中钢柱子和钢吊车梁已经出现不同程度的锈蚀,现由于作业生产需要增加吊车吨位,因此需要对厂房进行现场的检测,根据厂房的实际情况进行等级评定,并对腐蚀严重且无法满足吊车吨位加大要求的柱子及吊车梁,采取"加大构件截面法"进行加固处理。为同类钢结构厂房的加固改造提供理论依据和借鉴作用。  相似文献   

4.
根据硫酸站老厂房梁、板、柱与基础的破坏特征,考虑截面损失对构件承载力的影响,进行厂房结构加固时,梁、柱与基础采用外包配筋混凝土的方法,板按新、旧混凝土板变形协调的方法进行加固处理.这种加固方法经济可行,施工方便.  相似文献   

5.
李丽华 《甘肃科技》2009,25(9):134-136
托梁拆柱,属于一种综合性技术,增加梁截面有效高度,扩大截面面积,加强梁配筋,从而提高梁正截面抗弯,斜截面抗剪能力提高截面刚度,起到加固补强增强室内建筑物的有效使用功能。适用于已有建筑物的加固改造;与传统做法相比,具有施工时间短、费用低、对生活和生产影响小等优点,但对技术要求较高,需由熟练工人来完成,才能确保安全。  相似文献   

6.
某炼钢厂平炉改转炉工程,转炉基础落在原有平台柱基础、厂房柱基础、平炉设备基础、深水井等老基础上.该文对该场地条件下的几种地基处理方案进行了比较,最终选择了混凝土挤密桩这一最佳方案.从地基加固、挤密桩设计和构造要求等方面对该方案进行了论证,并应用试验对地基处理结果进行了验证.说明了这种场地条件下,采用混凝土挤密桩是经济、实用、合理的.  相似文献   

7.
随着建筑业的发展,加固工程越来越多。目前加固方面的规范主要有《混凝土加固技术规范》CECS25:90。对于上部结构荷载增加而对柱子的加固方法有:加大截面加固法、外包钢加固法、粘钢加固法等,其中加大柱子截面法俗称外包柱施工,该方法施工方便且承载力提高效果明显。  相似文献   

8.
挡土墙是一种常见的路基支挡构造物,当基础埋置深度或挡土墙基底应力验算不满足相关规范及工程要求时可采用桩基托梁挡土墙.结合某高速公路路堤边坡加固工程实例,详细介绍了桩基托梁挡土墙的设计方案及施工工艺要点,本实例对类似工程有一定的借鉴作用.  相似文献   

9.
采用数值积分方法模拟计算了轴心受压铜骨-铜管高强混凝土组合柱的荷载-变形关系曲线,计算结果与试验结果吻合良好.在此基础上通过大量计算,研究了套箍指标、配骨指标、长细比和偏心距对组合柱承载力的影响.计算分析表明,铜管、铜骨和混凝土的协同工作,可有效地提高柱子的承载力.  相似文献   

10.
钢丝网外喷高强砂浆加固混凝土结构是一种新型结构加固方法.对4根钢丝网外喷高强砂浆加固钢筋混凝土柱和3根对比钢筋混凝土柱进行了轴压试验研究,并根据平衡方程提出了试验用的加固构件轴压极限承载力计算公式,理论计算结果与试验结果吻合的较好.研究结果表明,采用该加固方法能有效的约束柱子横向变形,并对提高钢筋混凝土柱的轴压承载力和延性有明显的效果.  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.
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   

15.
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   

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.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  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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