首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 312 毫秒
1.
为研究现浇剪力墙装配整体式框-剪结构的抗震性能,对2榀(其中1榀为装配式试件PCFW1,1榀为全现浇试件RCFW)1/2比例两层两跨混凝土框-剪结构试件进行拟静力试验,研究其破坏过程和机理、滞回性能、延性、耗能能力和塑性铰发展情况等.结果表明:装配式试件PCFW1与全现浇试件RCFW相比,其破坏过程、破坏机制和最终破坏形态基本相同.装配式试件PCFW1与全现浇对比试件RCFW的滞回曲线均较为丰满,试件的屈服荷载、峰值荷载、极限荷载均略大于全现浇试件RCFW的相应值,但其差值均小于10.0%,延性低于全现浇试件RCFW;灌浆套筒可以有效传递纵向钢筋应力;现浇剪力墙装配整体式框-剪结构中,顶层边节点处梁上钢筋弯锚可用钢筋焊端锚板代替.  相似文献   

2.
为了研究再生混凝土取代率对方钢管再生混凝土柱型钢再生混凝土梁框架节点抗震性能的影响,设计四个中节点试件进行低周反复加载试验,研究了试件的破坏过程与受力模式、抗震性能指标、节点连接处承载力计算方法.研究表明:试件均发生梁端混凝土的受弯破坏,钢管与梁端界面伴有黏结滑移迹象;试件滞回曲线饱满,受再生骨料取代率的影响不明显;各试件峰值承载力相近,理论计算值与试验值吻合较好,延性系数和等效黏滞阻尼系数均分别大于4和0.4,试件具有较好的抗震变形与耗能能力.  相似文献   

3.
装配式结构中预制框架梁与框架柱连接的可靠性尤为重要,是研究的热点。笔者提出一种预制装配式框架连接节点,该节点核心区采用预制钢管约束钢纤维自密实混凝土的形式,预制混凝土梁外伸钢筋与贯穿预制节点核心区的钢组件焊接连接、然后在梁端局部现浇钢纤维自密实混凝土实现预制混凝土梁与预制核心区的连接。为验证其可靠性,设计了1个装配式框架节点和1个对比的现浇框架节点进行滞回性能试验研究,对比分析了2种节点在延性、强度和刚度退化、耗能能力、梁端塑性铰区域弯矩-曲率等方面的差异。试验结果表明:所设计的2个试件均发生梁端塑性铰破坏,但贯穿装配式节点核心区的钢组件、外包钢管及柱钢筋均未屈服、核心区外包钢管也未发鼓曲;此外,该装配式框架节点的延性、耗能能力、承载力等指标均略高于现浇框架节点,说明该装配式框架节点能达到等同现浇的水平。  相似文献   

4.
进行了6个配置高强度、低弹性模量、高延性的不锈钢钢筋混凝土柱的拟静力试验,并与普通钢筋柱对比,研究其破坏形态、滞回曲线、骨架曲线、位移延性等抗震性能和承载力,并分析轴压比和纵筋配筋率的影响。结果表明:不锈钢试件均发生柱根部正截面压弯破坏;其滞回曲线与普通钢筋试件的相似,但耗能能力更好;不锈钢试件的位移延性系数比普通钢筋试件的略低,但其屈服位移和极限位移分别比普通钢筋试件的大21%~24%和2%~19%;不锈钢试件的受弯承载力计算值和试验值之比与普通钢筋试件的相近,平均为0.79,具有一定的安全储备;当箍筋间距大于100mm时,其约束作用对试件承载力的提高不明显。  相似文献   

5.
为了研究方钢管混凝土柱—不等高钢梁加腋框架节点受力性能,按1:3缩尺比例设计并制作了六个节点试件,进行了低周期往复荷载破坏试验。节点试件的加腋坡度及梁高差比是试验研究的主要参数。通过试验研究各参数对节点试件的破坏特点、抗剪承载力、滞回特性、延性及耗能能力、承载力退化与刚度退化等力学性能的影响,得出以下结论:试件破坏是由于节点抗剪承载力不足导致的,但由于加强环板的约束及梁端加腋的存在,破坏出现在下环板与柱端交接处;各试件滞回曲线整体相对饱满;随着节点试件加腋坡度的变缓,其极限承载力提高,延性系数增加,耗能能力增强,刚度退化速率略有加快;当梁高差比由0. 39增加至0. 46时,节点试件反向加载极限承载力提高(以拉为反向加载),当梁高差比由0. 46增加至0. 53时,节点试件反向加载极限承载力降低,且随着梁高差比的增加,节点试件正向加载极限承载力逐渐降低(以推为正向加载),延性系数降低,耗能能力减弱,刚度退化速率变化不大;梁端加腋能有效改善节点核心区受力性能。  相似文献   

6.
为研究T形件螺栓连接卷边钢板组合截面PEC柱-钢梁组合框架结构的抗震机理,设计制作了一榀底部两层单跨组合框架1/2缩尺试件并进行水平低周往复荷载试验.基于试验现象和测试数据,从试件结构的滞回特性、水平抗侧刚度退化、节点性能、耗能能力与抗震延性、塑性机构发展进程与延性破坏模式等性能进行分析.研究结果显示:T形件螺栓连接增大了梁柱节点刚度,改善了结构的整体性,试件的初始抗侧刚度较大、极限承载力较高;T形件螺栓连接使得梁端塑性铰形成位置远离节点区,试件滞回曲线较为饱满,试验结束对应承载力未出现明显降低,且对应整体侧移角、位移延性系数和等效黏滞阻尼系数表明试件具有良好的抗倒塌能力、抗震延性与耗能能力;T形件螺栓连接PEC柱-钢梁组合框架试件塑性破坏机构发展进程为T形件端部梁截面和PEC柱脚相继形成塑性铰,实现了框架结构的理想延性耗能模式.  相似文献   

7.
为研究含圆钢管的方形叠合柱-钢梁连接节点的滞回性能:设计了以轴压比、楼板厚度为参数的3个柱顶施加轴向恒力、梁端施加竖向反复荷载的节点拟静力试验;研究了节点的破坏过程和破坏模态;分析了反复荷载对试件刚度、延性的影响规律;在试验的基础上,利用有限元软件ABAQUS对节点进行数值模拟;选取典型节点试件模拟了破坏过程,并进行了参数分析。计算得到的试件破坏模态和滞回曲线同试验结果总体上吻合良好,结果表明:较大的轴压力限制了节点核心区初始裂缝的出现时间与宽度;不带楼板试件和带楼板试件的破坏模式分别为梁端受弯-节点核心区受剪破坏和柱端压弯-节点核心区受剪破坏;该类节点滞回关系曲线均较饱满,耗能能力强,具有良好的抗震性能。  相似文献   

8.
制作了3个自密实混凝土加固框架中节点,采用MTS伺服加载系统进行自密实混凝土加固节点的拟静力试验,研究不同轴压比对自密实混凝土加固节点抗震性能的影响.3个加固试件的轴压比分别为0.1,0.2,0.3.通过对试件破坏过程、新老钢筋应变、荷载位移滞回曲线等试验结果的分析得到:随柱端轴压比的增加,柱端压力对节点核心区的约束作用逐渐增大,加固节点的抗剪承载力、耗能能力、结构刚度等随之提高,而加固节点的极限位移、位移延性系数随之降低.  相似文献   

9.
为研究预制梁、预制柱之间连接的抗震性能,设计了一种新型装配整体式钢筋混凝土框架边节点,并完成了1个整浇RC试件和2个纵筋搭接长度不同的装配式PC试件的低周反复载荷试验。研究了其破坏过程、破坏形态、滞回曲线、骨架曲线、位移延性、强度退化及耗能能力等内容。结果表明:装配式试件与整浇试件具有相似的破坏过程,破坏模式为梁端塑性铰区弯曲破坏,节点核心区处于弹性状态,节点整体性能良好,承载能力、初始刚度和耗能能力与整浇试件相当。基于“钢筋直锚短搭接”高效连接技术的装配式框架边节点连接可靠、施工方便、质量可控,具有较好的工程应用价值。  相似文献   

10.
为研究端板厚度和连接方式对装配式偏心支撑钢框架抗震性能的影响,进行了2个不同端板厚度的偏心支撑半刚接钢框架和1个焊接连接的偏心支撑刚接钢框架的拟静力试验.结合试验研究结果,对装配式偏心支撑钢框架试件的破坏形态、荷载-位移滞回曲线、骨架曲线、侧移延性系数、等效粘滞阻尼系数进行了深入分析.试验结果表明:螺栓端板连接偏心支撑钢框架抗震性能良好.端板厚度对装配式偏心支撑钢框架耗能能力具有一定影响,端板厚度由16 mm增加到24 mm,由于破坏延迟,耗能梁段极限剪切承载力提高43.32%. 同时,受高强螺栓-端板连接滑移的影响,偏心支撑半刚接钢框架滞回曲线呈“弓形”,表现出一定的“捏缩”现象.  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.
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   

13.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号