钢筋套筒灌浆搭接连接的预制框架柱抗震试验

为研究竖向钢筋采用新型套筒灌浆搭接连接的预制柱的抗震性能,在已研发的Ⅰ、Ⅲ型套筒灌浆搭接接头的基础上进行了1个现浇柱、2个预制柱的拟静力试验.试验现象如下:现浇柱的初始水平裂缝出现在根部,预制柱由于套筒约束了混凝土的竖向应变,初始水平裂缝出现在套筒顶面;极限状态下现浇柱压碎区段长,预制柱压碎区段短.试验结果表明:预制柱的开裂、屈服荷载略大于现浇柱,极限荷载高于现浇柱;预制柱的开裂、屈服位移与现浇柱相近,极限荷载时位移、极限位移、延性系数大于现浇柱.由于预制柱根部套筒范围内箍筋加密,预制柱的耗能能力略优于现浇柱.Ⅰ、Ⅲ型套筒上下方钢筋应变基本一致,表明Ⅰ、Ⅲ型套筒在预制柱中能够很好的传递钢筋应力.     

钢筋套筒浆锚连接的预制柱试验性能研究

为研究竖向钢筋套筒浆锚连接的预制柱的力学性能,完成了6个柱试件的拟静力试验,其中2个为现浇试件.试验结果表明:套筒浆锚连接能够有效传递竖向钢筋的应力;预制柱的破坏形态与现浇柱基本一致,为拉区混凝土开裂、竖向钢筋受拉屈服、压区混凝土压碎的受弯破坏;预制柱试件的刚度和耗能能力与现浇墙试件相当,极限位移角达1/1219～1/49.     

套筒约束两根钢筋浆锚搭接拉伸试验研究

为了改善预制构件钢筋连接的施工便利性及提高连接效率,提出两根钢筋套筒约束浆锚搭接接头,进行了12个以搭接长度为变化参数的Ⅱ型搭接接头、63个以搭接长度和钢筋直径为变化参数的Ⅲ型搭接接头的拉伸试验,研究了试件的破坏形态、极限承载力、力-位移曲线及钢筋和套筒的应变,提出搭接接头的平均黏接应力的计算公式.与单根钢筋的I型搭接接头的相同之处为:试件破坏形态有套筒外钢筋拉断及钢筋与灌浆料滑移两种,套筒端部环向拉应变大于套筒中部,套筒中部近钢筋处拉应变大于远钢筋处.直径相同的钢筋拉断试件,套筒中部远钢筋侧环向应变随搭接长度增加而减小;不同处:Ⅲ型接头椭圆型套筒对灌浆料的约束力小于I型接头圆形套筒,造成Ⅲ型接头加载后期套筒外钢筋未表现出明显的屈服台阶,Ⅲ型接头钢筋滑移试件极限荷载时套筒中部远钢筋处环向应变未表现出I型接头随直径d增大而增大的趋势,Ⅲ型接头的搭接长度较大.     

竖向新型连接装配式剪力墙抗震性能试验研究

为综合评价基于钢板网成孔的竖向钢筋搭接连接的装配式混凝土剪力墙抗震性能,制作了足尺试件,进行了拟静力试验并与现浇试件对比.试验结果表明:对于最终破坏形态,钢板网成孔的竖向钢筋搭接连接试件与现浇试件基本相同,初始裂缝出现位置不同.两者滞回曲线均较饱满,骨架曲线走势基本一致,耗能能力接近.各装配试件与现浇试件极限位移角为1/55到1/43,位移延性系数为4到5,满足延性要求.钢板网成孔的竖向钢筋搭接连接试件较现浇试件各阶段荷载承载能力有所降低.装配式混凝土剪力墙结构水平拼缝采用合理构造可以达到与现浇结构相接近的延性、承载能力以及抗震耗能能力.     

装配式地铁车站外墙-底板节点抗震性能研究

针对装配式地铁车站结构,提出一种新型的车站外墙-底板连接节点。该节点通过车站单侧半预制墙板与底板伸出的竖向U型钢筋搭接连接来实现侧墙与底板间的内力传递。为研究该节点的抗震性能,结合实际工程设计制作PSJ1,PSJ2和PSJ3这3个节点区位置各不相同的足尺预制拼装节点试件,并通过拟静力试验研究节点的破坏形态、承载能力、滞回性能以及U型筋搭接连接的传力性能。研究结果表明：U型钢筋的搭接连接能够有效传递钢筋应力;搭接连接区可能出现钢筋弯弧段的断裂破坏以及弯弧内部混凝土的压碎破坏,两种连接失效模式均可归因于钢筋与混凝土之间的黏结退化;将U型筋搭接位置设置于外墙的加腋段,可有效防止连接失效对节点抗震性能的影响,使节点的极限承载力进一步提高。     

装配式混凝土剪力墙水平拼缝U型闭合筋连接抗震性能试验研究

为综合评价水平拼缝U型闭合筋连接的装配式混凝土剪力墙抗震性能,对其足尺试件进行了低周反复荷载试验并与现浇试件对比.试验结果表明:对于破坏形态,U型闭合筋连接试件与现浇试件基本相同;由于水平拼缝的存在,U型闭合筋连接试件的受力全过程的表现形式与现浇试件不相同;两者滞回曲线均较饱满,骨架曲线走势基本一致,耗能能力接近;两者极限位移角分别为1/46和1/49,位移延性系数均为4,满足延性要求;U型闭合筋试件较现浇试件初期刚度、开裂荷载有所降低,但峰值荷载承载能力提高.装配式混凝土剪力墙结构水平拼缝采用合理构造可以达到与现浇结构相当的承载能力、延性以及抗震耗能能力.     

半灌浆套筒连接件抗拉伸性能有限元研究

为了研究半灌浆套筒连接件的抗拉伸性能,采用数字建模方法建立半灌浆套筒有限元模型,研究了钢筋直径、灌浆料强度、钢筋锚固长度、钢筋偏置缺陷等参数的影响规律。研究结果表明,所建立有限元模型能很好地模拟半灌浆套筒连接件的拉伸全过程,且分析结果与试验结果较吻合;随着钢筋直径的增大,半灌浆套筒连接件的极限荷载值和极限位移值均增大;当钢筋锚固缺陷大于2 d时,灌浆料与混凝土间将产生粘结滑移,为防止灌浆料被压碎,建议灌浆料强度应大于100 MPa;钢筋偏置缺陷导致连接件强化阶段荷载值略微降低,沿钢筋受力方向的应力值增大。     

装配式混凝土剪力墙抗震性能试验研究

为了使装配式剪力墙在水平拼缝处得到可靠连接,引入扣接封闭箍筋,分别对1个装配式剪力墙试件和1个现浇剪力墙试件进行低周反复荷载加载试验,并分析两试件的强度、刚度、位移延性及耗能能力等抗震性能指标。结果表明:扣接封闭箍筋可以限制约束区混凝土的横向变形,对波纹管浆锚搭接钢筋形成较好约束,并改善纵筋间的间接搭接性能;与现浇剪力墙试件相比,装配式剪力墙试件的延性和耗能能力相当,但承载能力有较大提高。     

装配式地铁车站侧墙-顶板节点抗震性能试验研究

针对装配式地铁车站结构,提出了一种新型的车站顶板与侧墙连接节点.该节点通过车站侧墙顶部伸出的竖向U形钢筋与预制顶板两端伸出的水平U形钢筋搭接连接,从而实现侧墙与顶板间的内力传递.结合实际工程,设计制作了3个U形筋搭接构造形式各不相同的装配式足尺节点试件.通过拟静力试验,研究了节点试件的破坏形态、滞回性能、承载能力、变形性能以及耗能能力.结果表明,装配式节点试件的破坏形态包括U形筋弯弧内侧混凝土的局部受压破坏和侧墙剪切破坏.节点试件的位移延性系数为2.7-3.4,试件顶板端部的极限转角为1/22～1/27.增加节点中受拉钢筋的搭接长度,可以有效确保U形筋搭接连接在往复荷载作用下的有效性.     

四种灌浆连接节点的静力性能及比较分析

对国内外已有的预制混凝土结构钢筋灌浆连接节点:套筒灌浆连接节点、波纹管浆锚连接节点、插入式预留孔浆锚搭接节点和套筒约束浆锚搭接节点的构造形式进行了概述,并简单介绍了各种节点的静力性能.在横向约束形式、工作机理和临界长度等方面对四种灌浆连接节点进行了比较.     

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.     

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.     

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.