碳纤维布增强钢筋混凝土构件轴心抗拉试验研究

针对钢筋混凝土受拉构件承载力不足的问题,在6根碳纤维布加固钢筋混凝土构件轴拉试验基础上,对配筋率、碳纤维布层数对构件开裂荷载、极限荷载的影响进行了分析,并提出了加固构件的抗拉承载力计算公式.研究表明.粘贴碳纤维布可以有效地提高钢筋混凝土轴拉构件极限承载力,限制裂缝宽度.所提计算公式与试验结果有较好的一致性,可供实际工程设计参考.该研究成果对钢筋混凝土轴心受拉加固具有理论指导意义和工程应用价值.     

碳纤维布增强RC构件小偏心抗拉数值分析

结合在役钢筋混凝土受拉构件承载力不足的特点, 采用大型通用有限元软件建立了碳纤维布增强钢筋混凝土小偏心受拉构件计算模型, 对碳纤维布加固后碳纤维布层数、配筋率等对构件开裂载荷、极限载荷的影响进行了分析,并通过6根构件进行试验对比. 研究表明, 粘贴碳纤维布可以有效地提高钢筋混凝土偏拉构件极限承载力, 而其对开裂载荷影响较小. 计算结果与试验数据有较好的一致性, 可供实际工程设计参考.研究成果对钢筋混凝土小偏心受拉加固具有理论指导意义和工程应用价值.     

CFRP加固钢筋混凝土简支梁桥的设计计算

由于碳纤维受力过程中特有的线弹性性质，粘贴加固计算时需判断加固截面的应变状态。结合某钢筋混凝土简支T形桥梁粘贴碳纤维片加固设计，应用碳纤维片加固受弯构件正截面强度计算公式，介绍了该公式在加固设计及强度复核中的应用方法及注意事项。加固前后的荷载试验结果表明，粘贴碳纤维片可大大提高主梁的抗弯刚度，增加主梁的承载潜力，有效抑制了混凝土的开裂。     

钢板和碳纤维布加固不同损伤状态下受弯构件的荷载试验研究

基于钢板加固和碳纤维布加固完好状态下和正常使用极限损伤状态下的受弯构件的破坏荷载试验,研究钢筋混凝土受弯构件在采用粘贴钢板加固和粘贴碳纤维布加固措施后,其挠度、裂缝及应变等的发展变化规律.对比分析完好状态下和正常使用极限损伤状态下采用不同的加固方式,受弯构件极限承载力提高幅度的差异并将受弯构件的其他力学控制指标进行对比分析,综合检验评定其加固效果.试验结果表明:两种加固措施对提高在不同损伤状态下的钢筋混凝土受弯构件的抗弯承载力都具有显著效果,但完好情况下的加固效果优于受损情况,钢板加固措施优于碳纤维布加固.     

碳纤维布加固钢筋混凝土箱梁力学性能研究

CFRP是一种新型高性能材料,已作为加固钢筋混凝土构件的重要材料,拥有较好的物理、力学性能,且施工工艺成熟和加固混凝土构件时占用空间较少等优点.由于CFRP材料优点突出,在现有加固材料中被广泛采用,因此针对CFRP加固钢筋混凝土箱梁在弯扭复合受力下承载能力的研究,显得尤为重要.对CFRP加固钢筋混凝土箱梁在复合受力下展开弯扭承载力试验进行了研究,试验结果表明:纵向CFRP加横截面方向粘贴U形CFRP加固箱梁效果最佳;箱梁试件表面开裂之前,对加固箱梁试件与未加固箱梁试件进行对比分析,箍筋剪应变差异很小,但是表面开裂之后,加固材料的效果得到充分体现;对箱梁进行U型加固方式是抗扭承载力提高的主要因素,在改善箱梁试件的极限扭矩方面,横向U型CFRP加固效果比纵向CFRP加固效果更为显著.     

碳纤维布增强二次受力RC构件轴拉计算方法

结合在役钢筋混凝土受拉构件承载力不足的特点,推导了碳纤维布增强二次受力钢筋混凝土构件轴心受拉计算表达式,探讨了预加载程度、持载程度和构件开裂载荷、极限载荷之间的定量关系,并进行了8根碳纤维布增强二次受力钢筋混凝土构件轴心抗拉性能试验研究,分析预加载程度、持载程度对构件开裂载荷和极限载荷的影响.结果表明,粘贴碳纤维布可以有效地提高二次受力钢筋混凝土轴心受拉构件极限承载力.所提表达式与试验数据有较好的一致性,可供实际工程设计参考,并对二次受力钢筋混凝土轴心受拉加固具有理论指导意义和工程应用价值.     

粘贴碳纤维或钢板加固受弯构件的效果对比

粘贴碳纤维或钢板是桥梁加固中常用的两种被动加固方法,以粘贴碳纤维布和钢板加固钢筋混凝土T梁为例,从加固计算原理、加固后承载力、各材料强度和刚度方面对比分析加固效果.计算结果表明:粘贴1~3层碳纤维布加固与粘贴4~10 mm钢板加固对比,前者对梁的承载力及刚度提高效果都不如后者;粘贴碳纤维布的高强度没有得到充分发挥,加固对各材料的应力强度改善不明显,适合于构件的抗裂性加固;若要提高梁的承载力和整体刚度,采用粘贴钢板加固比较合适.     

粘贴钢板加固钢筋混凝土梁式桥的分析研究

讨论了用粘贴钢板的方法加固钢筋混凝土梁式桥的分析与设计方法.根据有关试验结果所得出的这类加固构件的破坏模式,提出正截面强度、接触面应力的分析方法并用于设计中,对加固后梁的抗剪切能力亦进行了论述.     

考虑分阶段受力的粘钢加固钢筋混凝土梁抗弯承载力计算

粘钢加固钢筋混凝土受弯构件,加固前原构件截面已存在应变和应力,而新粘钢板在新增荷载下开始受力,桥梁构件具有不同受力阶段的特点。现有《公路桥梁加固设计规范》中未给出T形截面梁粘贴钢板加固受弯构件正截面承载能力计算公式,而且也不能反映各阶段材料的受力特点。本文根据粘贴钢板加固钢筋混凝土T形截面梁发生适筋破坏,建立了正截面极限承载力计算公式,并对粘贴钢板的应力取值进行了分析,在常用的粘贴钢板厚度内,可直接取钢板的抗拉强度设计值。并根据平截面假定,建立了各阶段混凝土、钢筋和钢板应力的计算公式,材料的最终应力按叠加原理计算得到。算例分析表明,本文所建立的正截面抗弯承载力计算公式可行,可供桥梁加固设计参考。     

碱性环境下建筑结构防腐与加固技术研究

通过工程实例对碱性环境下建筑结构材料的腐蚀作用和加固方法进行了探讨,针对强碱环境和构件材料的具体条件,采取了耐碱腐蚀的防腐材料和防腐工艺做法,并针对强碱环境下不同构件因腐蚀造成的强度损失的具体条件以及荷载的作用情况采取了多种补强及加固方法,(如:钢筋混凝土采大型屋面板用高强环氧防腐砂浆抹面的防腐方法;钢平台、钢支撑采用刷70-H环氧铁红防腐涂料、H06-3环氧云铁防锈漆的防腐方法;钢筋混凝土屋架、平台梁采用采用碳纤维布粘贴,外刷RP-W防腐砂浆的防腐方法;赤泥车间还采用了卸除部分荷载和粘贴碳纤维相结合的方法等),经长期实践应用证明取得了较好的防腐和加固效果.     

Markedness and its Interpretation in Language Use

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Features of Women's language

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.     

A computer generator for randomly layered structures

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

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

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。     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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Achieving Unusual States of Matter Under High Pressure

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     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with