CFRP-不锈钢夹层管混凝土柱轴压试验及承载力计算方法

为了提升薄壁不锈钢结构的承载性能和耐久性,在不锈钢管内外壁粘贴碳纤维增强复合材料（Carbon Fiber-Reinforced Polymer,CFRP）复合约束海水海砂混凝土,制得一种CFRP-不锈钢夹层管海水海砂混凝土结构。以CFRP粘贴层数和方式为变化参数,对18个短柱试件进行了单调轴心受压试验,观察了试件的受力破坏过程及形态,获取了荷载-位移曲线和材料应变分布数据,分析了试件轴压力学性能的变化规律。结果表明：内外贴CFRP能有效地提高结构的承载能力和变形能力;无CFRP和内贴CFRP试件的破坏形态均为剪切破坏,但破坏形态会随着外贴CFRP层数的增加向腰鼓破坏转变;在相同粘贴方式下,试件的承载能力、变形能力和耗能能力随着CFRP层数的增加呈非线性提高;在相同粘贴层数下,内贴CFRP的力学性能提升效果优于外贴CFRP,粘贴1层和2层CFRP时,内贴试件的极限承载力相较于外贴试件能再提高5.6%和6.7%,同时内贴1层CFRP的试件的耗能能力与外贴2层CFRP的相当;应变分析显示,在试件破坏前,CFRP与不锈钢协同工作良好。文中最后基于极限平衡法,考虑不锈钢的应变硬化效应,提出了C...     

轴压下CFRP—钢管约束混凝土柱试验研究

为研究CFRP—钢管约束混凝土柱试件在B式(仅在核心混凝土施加轴压)加载下的轴压力学性能,采用轴压试验的方法对18根CFRP—钢管约束混凝土试件进行核心混凝土轴向加载,分析混凝土强度、CFRP包裹层数和CFRP约束效应系数对试件轴向承载力和轴向位移的影响。试验结果表明,CFRP约束效应系数对试件轴压承载力提高系数贡献最大,CFRP约束效应能防止钢管的屈曲同时限制混凝土裂缝的发展,增大核心混凝土强度和增加CFRP层数,试件轴向承载力有显著提高。同时制作了6根试件进行A式B式加载对比试验,试验结果表明B式加载方式的极限承载力均大于A式加载,B式加载试件在整个加载过程中CFRP都对混凝土产生约束作用,试件的轴压性能相较于A式更加优良。     

小口径CFRP-方截面钢管混凝土受弯性能研究

为研究小口径CFRP-方截面钢管混凝土的受弯性能,使用钢管外径分别为30、32、35 mm的3种试件(分别命名试件A、B和C)开展12组三点弯曲试验,观察试件的破坏形态并获得荷载-位移曲线。通过测得试件应变变化,对试验构件受弯性能进行分析。利用有限元软件ABAQUS对试件进行非线性有限元分析,并对钢管与水泥之间的黏结能力、水泥立方体试块抗压强度以及CFRP布厚度3组参数进行参数敏感性分析。研究结果表明：钢管内填充水泥与外缠CFRP布均可以提高试件的抗弯承载力最大值以及抗弯刚度;当钢管、水泥、CFRP布3种材料结合在一起时,提升效果最为明显,A、B、C这3种试件的抗弯承载力最大值分别提高了81.6%、93.3%和92.6%;钢管内是否填充水泥与试件的最终破坏形态有明显关联。有限元分析与试验所得荷载-位移曲线吻合较好,破坏模式一致。CFRP布厚度对抗弯承载力最大值以及梁的抗弯刚度有明显影响。     

工字形CFRP-高强方钢管高强混凝土轴压短柱有限元分析

目的将工字形CFRP型材置入钢管混凝土截面型心处,研究高强方钢管高强混凝土轴压短柱的受力性能.方法对典型构件的应力-应变曲线、组合柱的受力机理进行分析,并定义了6个特征点.研究在构件受力的各个特征点的方钢管、混凝土和工字形CFRP分担的纵向荷载,分析内置工字形CFRP配置率、核心混凝土抗压强度、钢材屈服强度、含钢率等因素对组合柱力学性能的影响.结果内置工字形CFRP的高强方钢管高强混凝土轴压短柱极限承载力随着混凝土强度、钢材屈服强度、CFRP配置率以及含钢率增加而增加,而钢材屈服强度以及混凝土强度对构件荷载-位移曲线初始刚度影响较小.结论高强方钢管高强混凝土的各组分受力随着高度变化而变化,构件受力性能较好并承载力较高.     

钢管高钛矿渣砂超高强混凝土短柱轴压力学性能试验研究

为研究钢管高钛矿渣砂超高强混凝土短柱的轴压力学性能,完成了10根钢管高钛矿渣砂超高强混凝土短柱轴压试验,重点考察高钛矿渣砂取代率对其力学性能的影响。结果表明：高钛矿渣砂取代率对钢管混凝土试件的破坏形态、荷载-位移曲线、应力-应变曲线、应力-横向变形系数曲线规律无明显影响,试件均为剪切破坏模式;随着高钛矿渣砂取代率的增加,钢管混凝土试件的承载力与初始刚度随之增加,在取代率为60%时,均达到最大值;由于核心混凝土强度过高,试件含钢率偏小,钢管对核心混凝土约束效应有限,实测承载力小于规范计算承载力。     

CFRP约束圆钢管高强混凝土短柱轴压试验研究

为研究混凝土强度、径厚比、CFRP(碳纤维增强复合材料)层数及CFRP包裹方式等参数对CFRP约束圆钢管混凝土轴压静力性能的影响,进行了6个圆钢管混凝土短柱和18个CFRP-钢管混凝土短柱的轴压对比试验.研究发现CFRP的约束对圆钢管混凝土承载力有较显著的提升,且承载力的提高幅度随着CFRP的增加而增加.钢管高强、超高强混凝土短柱的破坏形态呈现为剪切破坏,延性较差,CFRP的约束可以改善其延性,且CFRP层数越多延性越好.半包CFRP试件性能接近于全包CFRP试件性能.随径厚比增大,CFRP约束效果下降.若黏结良好,试件失效前,CFRP与钢管能保持协同工作;最后选取了3个经典的CFRP约束钢管混凝土轴压承载力公式进行验算,发现基于CFRP和钢管双重约束的公式能较好地预测其承载力.     

内压作用下CFRP/钢复合管受力性能试验研究

为研究内压作用下碳纤维增强复合材料(carbon fiber reinforced plastic, CFRP)/钢复合管的受力性能,进行了8根CFRP/钢复合管及1根普通钢管的内压荷载试验.试验中考虑的变量有碳纤维布层数、碳纤维布轴向及环向搭接长度.试验结果表明:外贴单层碳纤维布时,CFRP与钢管的协同变形效应随碳纤维布轴向及环向搭接长度的增加而增强,当轴向及环向搭接长度分别达到50mm及200mm时CFRP与钢管变形趋于一致;内压作用下CFRP/钢复合管的荷载-应变曲线呈近似双线性的变化规律,其刚度、屈服强度及极限强度均随碳纤维布层数的增加而增大,试件典型破坏形态为CFRP环向受拉断裂.最后,基于试件典型破坏特征,提出了适用于CFRP/钢复合管的强度计算模型.     

钢管轻集料混凝土界面黏结滑移过程分析

为探究钢管轻集料混凝土黏结滑移受力过程和机理,通过4个钢管轻集料混凝土柱推出试验,分析钢管轻集料混凝土界面黏结滑移受力过程.从钢管外壁应变变化、位移-荷载曲线、黏结破坏强度以及相应位移角度分析长细比和紧箍系数对钢管轻集料混凝土黏结滑移的影响;通过详细分析加载过程中钢管外壁应变变化研究构件黏结滑移受力过程.试验结果表明:核心混凝土全界面发生相对滑移时,滑移荷载主要受紧箍系数直接影响,紧箍系数越大相应荷载越大;滑移过程中,钢管外壁纵向应变变化反映其位移-荷载曲线趋势;钢管内壁混凝土接触界面始终对轻集料混凝土有较大的环向约束作用,长细比越大在钢管端部环向作用越明显;紧箍系数不变,黏结破坏荷载对应位移随长细比增大逐渐递增.     

CFRP-钢管混凝土加固RC短柱偏压性能试验

通过8根碳纤维增强复合材料(CFRP)-圆钢管自密实混凝土复合加固和4根圆钢管自密实混凝土加固钢筋混凝土(RC)方形短柱的受压试验,研究了复合加固RC短柱偏压受力性能,分析了偏心距和CFRP层数对复合加固RC短柱的破坏形态、承载力、刚度和延性的影响.复合加固RC短柱的破坏形态包括端部混凝土的压碎、受压区钢管屈曲和CFRP断裂.加固试件表现出延性破坏特征,达到极限承载力后,仍具有一定的承载和变形能力.随着偏心距的增大,加固试件变形增大;偏心距为20,40和60 mm的试件极限承载力平均降低幅度分别约为25%,37%和42%.随着CFRP层数的增加,加固试件变形减小,延性降低;CFRP层数为1和2的试件极限承载力平均提高幅度分别约为16.2%和39.8%.     

圆CFRP-钢复合管内填砼构件的受弯性能研究

对16根圆CFRP-钢复合管内填砼受弯构件以及4根圆钢管砼受弯构件开展静力试验并分析实验结果。对于未包裹纵向CFRP的试件,其荷载-跨中挠度曲线类似于对应的圆钢管砼构件的曲线;对于包裹纵向CFRP的构件,其荷载-跨中挠度曲线可以划分为以下几个阶段：弹性阶段、弹塑性阶段和下降段。圆CFRP-钢复合管内填砼受弯构件的延性要好于圆FRP筒内填混凝土受弯构件。对于具有相同钢管约束效应系数的试件。承载力提高率随着纵向CFRP层数的增大而增大。从加载之初直到最大承载力．钢管和CFRP筒在环向和纵向都可以协同工作。纵向受压最大点的环向扣应变最大,纵向受拉最大点的环向压应变最大,纵向受拉最大点的钢管对核心砼没有套箍作用。从加载之初直到大约0．8倍的极限承载力,试件纵向应变沿截面高度的分布基本符合平截面假定。纵向CFRP可以显著提高试件的刚度。     

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

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.     

Design and analysis of generic LBS application developing platform

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.     

橡胶颗粒沥青混合料低温抗裂性试验研究

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.     

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。     

Quantitative trait loci （QTLs） for quality traits related to protein and starch in wheat

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.     

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.     

The Analects and the Moment in Peking——The influence of a Confucian education system on the personality formation,the way of thinking and the fate of the main characters

0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation＇s behavior in their social life throughout the long history is beyond list.