高强钢筋约束混凝土柱的抗震性能

以普通钢筋(400 MPa)和高强钢筋(1000 MPa)为约束箍筋,通过低周反复水平加载试验,对比分析了6组不同配筋率和间距的高强钢筋约束混凝土柱的轴压破坏形态和抗震性能.结果表明:普通钢筋约束混凝土试件的位移延性分别低于相同配筋率下的高强钢筋约束混凝土试件;无论是在相同配箍率还是在相同箍筋间距条件下,高强钢筋约束高...     

高强方钢管约束UHPC短柱轴压性能研究

使用通用有限元软件ABAQUS分析了钢材屈服强度、方钢管厚度、UHPC强度对高强方钢管约束UHPC短柱轴压性能的影响。首先使用ABAQUS对已有的普通钢管约束混凝土试验进行计算,结果与试验值基本一致。在此基础上建立了高强方钢管约束UHPC短柱模型,对比了不同参数下构件荷载-位移曲线、荷载-纵向应变曲线的变化特征。研究表明:构件前期刚度受混凝土强度影响很小,但由于增加混凝土强度使构件套箍系数降低,工作曲线下降段斜率增大,延性下降。钢管屈服强度的提高对构件的延性有很大改善,但对极限承载能力影响较小。核心混凝土强度是影响高强钢管约束UHPC短柱承载能力的主要因素,由于钢管不直接承担纵向荷载,仅对混凝土产生材料性能上的影响,钢管约束混凝土应看做混凝土的一种。     

箍筋约束高强混凝土柱应力应变曲线的非线性有限元分析

利用ANSYS模拟四根不同配箍率的高强混凝土轴压柱,分析了各柱的裂缝图和应力应变曲线。结果表明,随着配箍率的增加,柱的延性和承载力可以得到提高;较好的验证了文献中的箍筋作用机理。     

混凝土异形柱构造配箍图的制作

《混凝土异形柱结构技术规程（JGJ149—2006）》提出按照最小配箍特征值确定箍筋加密区体积配箍率要求,相应箍筋配置方案需通过计算求得,应用不便。按《规程》要求,根据异形柱的抗震等级、截面形式与尺寸、混凝土强度等级、轴压比的大小,给出了具体的箍筋配置方案,并形成图表,方便设计人员设计、核查。     

高强砼框架柱抗震性能的试验研究

本文采用框架加荷系统对高强砼柱进行了反复荷载下的试验。以位移延性系数为指标,对影响高强砼柱延性的各因素进行了分析,提出了高强砼柱轴压比的限值和柱加密区箍筋最小体积含箍率的建议值,对高强砼偏心受压柱强度计算的基本假定进行了修正。供设计人员参考。     

焊接高强箍筋高强混凝土柱滞回特性研究

以2根焊接高强箍筋、高强混凝土柱试件为研究对象,进行低周反复水平荷载作用试验,研究体积配箍率的变化对柱滞回特性的影响.试验结果表明,高强混凝土柱体积配箍率较大的试件滞回曲线相对饱满,滞回环面积较大,累积滞回耗能大,吸收地震能量多,延性好.该研究结果对发展应用高强混凝土具有实际意义.     

冷轧带肋钢筋作箍筋对高强混凝土柱延性的影响

本文采用低强箍筋和高强箍筋的对比试验,对高强混凝上压弯构件进行了在反复荷载作用下的试验,得到了各试件的荷载-位移府回曲线,通过对荷载-位移滞回曲线、位移延性系数等的分析,研究了冷轧带肋钢筋作箍筋对高强混凝土柱延性的影响试验表明：高轴压比下的高强混凝土柱在高强度箍筋─—冷轧带肋钢筋、高配箍率下能获得很好的延性．     

核心配筋框架柱强度和刚度试验研究

本文通过核心配筋框架柱试件的低周反复伪静力试验,分析了影响核心配筋框架柱强度和刚度退化的主要因素.试验结果表明,轴压比是影响构件强度和刚度退化的主要因素,芯柱的箍筋对试件的强度退化有较明显的影响,核心骨架对柱子的强度和刚度退化有一定的补强作用.     

不同强度板柱节点混凝土有效强度计算方法探讨

对高强混凝土柱和普通混凝土板之间节点混凝土有效强度计算公式进行了综述分析,并结合大量试验结果的分析,得出了比较好的结果.     

高强箍筋约束混凝土的应力应变模型修正研究

为了确定可靠的高强箍筋约束混凝土应力-应变曲线关系,基于试件约束混凝土应力-应变曲线的特征,采用约束混凝土的应力-应变模型对试件进行计算,并将理论模型与试验曲线进行比较。在Razvi and Saatcioglu(1999)模型的基础上进行了修正,结果显示修正后的模型计算结果能够较好地反映试件的特征。研究结果可为高强箍筋约束混凝土构件的应用提供理论参考。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

Western and Eastern culture differences in commercial field

The communication of people partially is the communication of cultures. Culture has a direct effect on international commercial activities in all aspects. Different conceptions about time, space, equality, law and the like, lead people to deal with things in different ways. So to know cultures of the counterpart is to facil-itate our enterprises so as to have a smooth and successful communication in commercial activity.     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

风的曲线

Rosco and I wait for the fishermen to return.I sit at a wooden bench near the store at Mt.Baker Resort and watch the clouds change shape. Rosco has my belt around his neck and an eight foot tow chain hooked to a tree. Dogs must be on a leash. Ducks and rabbits are loose.     

团图为数的图中的闭团贯数

Given a graph G,a subgraph C is called a clique of G if C is a complete subgraph of G maximal under inclusion and |C|≥2. A clique-transversal set S of G is a set of vertices of G such that S meets all cliques of G. The clique-transversal number, denoted as TC (G), is the minimum cardinality of a clique-transversal set in G. The clique-graph of G, denoted as K (G), is the graph obtained by taking the cliques of G as vertices, and two vertices are adjacent if and only if the corresponding cliques in G have nonempty intersection. Let F be a class of graphs G such that F={G|K(G) is a tree}. In this paper the graphs in F having independent clique-transversal sets are shown and thus TC (G)/|G|≤1/2 for all G ∈ F.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.