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1.
Numerical analysis of ultimate strength of concrete filled steel tubular arch bridges 总被引：8，自引：0，他引：8
INTRODUCTION As a result of the combined effects of the rolled steel tube and the core concrete, Concrete Filled Steel Tubular (CFST) structures can effectively take ad-vantage of these two materials to improve the com-pressive strength and the ductility of the structures. This kind of structure is developing quickly in China and widely used in high-rise structures and bridges. Recently, due to the development of construction projects, numerous studies on CFST structures have been i… 相似文献
2.
A three-dimensional finite element model was established for a large span concrete filled steel tubular (CFST) arch bridge which is currently under construction. The arch rib, the spandrel columns, the prestressed concrete box-beam, the cast-in-situ concrete plate of bridge deck, the steel box-beam and the crossbeams connecting the two pieces of arch ribs, were modeled by three-dimensional Timoshenko beam elements (3DTBE). The suspenders were modeled by three-dimensional cable elements (3DCE). Both geometric nonlinearity and prestress effect could be included in each kind of element. At the same time a second finite element model with the same geometric and material properties excepted for the sectional dimension of arch rib was set up. Static dynamic analyses were performed to determine the corresponding characteristics of the structure. The results showed that the arch rib's axial rigidity could be determined by static analysis. The stability and vibration of this system could be separated into in-plane modes, out-of-plane modes and coupled modes. The in-plane stability and dynamic characteristics are determined by the arch rib's vertical stiffness and that of out-of-plane is determined by the crossbeams' stiffness and arch rib's lateral stiffness mainly. The in-plane stiffness is much greater than that of out-of-plane for this kind of bridge . The effect of geometric nonlinearity and prestress effect on bridge behavior is insignificant. 相似文献
3.
本文采用非线性有限元方法对哑铃型钢管混凝土拱桥进行面内弹塑性分析．以解放大桥的中孔拱桥为研究对象,分别考虑了施工阶段和成桥阶段的受力情况,计算了该桥在施工和成桥阶段的弹塑性稳定安全系数,并讨论了不同程度的初始挠度对弹塑性稳定安全系数的影响。分析结果可供哑铃型截面钢管混凝土拱桥的设计建设参考。 相似文献
4.
钢管混凝土系杆拱桥空间效应分析 总被引：11，自引：0，他引：11
建立平面与空间有限元模型，对郑州黄河公路钢管混凝土系杆拱桥(二桥)的活载横向分布系数、横粱、拱肋和系梁的受力特点进行比较分析，重点考察结构的空间效应问题，并分析了结构第一类空间稳定系数及其主要影响因素。分析结果表明，活载横向分布系数采用杠杆法与空间分析结果相近，可用于设计计算之中；系梁承受有较大的扭矩；吊杆横梁的受力性质接近于简支梁，而端横梁的受力要进行空间分析，考虑系梁扭矩的作用；K撑中的斜撑和系梁安装支架对提高结构稳定系数贡献较大。 相似文献
5.
李桂英 《甘肃广播电视大学学报》2004,14(3):16-17,21
对钢管混凝土系杆拱桥拱肋的两种架设方式进行了探讨，即竖向转体施工架设法和缆索、扣索分段吊装架设法，并对缆索、扣索吊装施工中的实施要点与措施进行了分析，同时讨论了两种架设方法的优缺点及适用范围． 相似文献
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The creep-induced deformation of the arch rib of concrete-filled steel tubular （CFST） arches under a sustained load can increase the bending moment, which may lead to earlier stability failure called creep buckling. To investigate the influences of concrete creep on the buckling strength of arches, a theoretical analysis for the creep buckling of CFST circular arches under distributed radial load is performed. The simplified Arutyunyan-Maslov （AM） creep law is used to model the creep behavior of concrete core, and the creep integral operator is introduced. The analytical solutions of the time-dependent buckling strength under the sustained load are achieved and compared with the existing formula based on the age-adjusted effective modulus method （AEMM）. Then the solutions are used to determine the influences of the steel ratio and the first loading age on the creep buckling of CFST arches. The results show that the analytical solutions are of good accuracy and applicability. For CFST arches, the steel ratio and the first loading age have significant influences on creep buckling. An approximate log-linear relationship between the decreased degrees of the creep buckling strength and the first loading age is found. For the commonly used parameters, the maximum loss of the buckling strength induced bv concrete creen is close to 40% 相似文献
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为了确定预应力混凝土箱粱的极限承载能力,进行了预应力混凝土连续箱梁的破坏性试验,提出一种有限元损伤分析方法模拟箱梁结构行为.基于实体退化壳单元对箱梁进行模拟,并考虑了结构材料的非线性效应.由于预应力混凝土箱梁中通常存在大量曲线预应力钢筋,提出一种组合单元,并用该单元模拟箱梁中的预应力钢筋,该方法可使结构分析时单元数量大大降低.试验结果和理论分析对比表明:提出的方法能够有效地用于预应力混凝土连续箱梁的破坏性试验计算分析中;研究的旧桥依然存在较大的极限承载能力. 相似文献
8.
黄玉宁郑永乾赖鹏松 《福建工程学院学报》2020,(4):329-335
采用有限元软件ABAQUS建立了不同加载角T形带肋和多室钢管混凝土压弯构件的计算模型,数值计算结果与试验结果吻合良好。对影响T形钢管混凝土柱水平荷载P-水平位移Δ关系曲线的参数进行分析,结果表明:加载角为0°时,T形钢管混凝土构件的承载力最低,在67.5°负向加载时,构件的承载力最大,比0°加载角构件大13%左右,加载角为45°~90°间承载力总体上差别不大。随着钢管屈服强度、混凝土抗压强度、钢管长厚比、带肋和多室T形钢管混凝土构件在斜向加载的承载力增加,在传统钢管混凝土基础上,提出了适用于不同加载角带肋和多室T形钢管混凝土压弯构件的承载力设计方法,简化计算公式与有限元结果、试验结果均吻合较好。 相似文献
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大跨预应力混凝土连续刚构桥墩梁结合部位受力复杂,且布置数量较多的预应力钢束,是刚构桥中的关键部位。结合昆明市城市三环路东段工程预应力混凝土连续刚构桥的设计方案,利用有限元分析软件ANSYS对墩梁固接区进行精细有限元局部分析,得到施工阶段及运营阶段墩梁固结区的应力分布。结果表明该结构预应力配束合理,施工阶段及运营阶段应力均满足设计规范要求。 相似文献
10.
Carbon fiber reinforced polymer(CFRP)bars were prestressed for the structural strengthening of 8 T-shaped rein-forced concrete (RC)beams of a 21-year-old bridge in China.The ultimate bearing capacity of the existing bridge after retrofit was discussed on the basis of concrete structures theory.The flexural strengths of RC beams strengthened with CFRP bars were controlled by the failure of concrete in compression and a prestressing method was applied in the retrofit.The field construction processes of strengthening with CFRP bars-including grouting cracks,cutting groove,grouting epoxy and embedding CFRP bars,surface treating,banding with the U-type CFRP sheets,releasing external prestressed steel tendons-were introduced in detail.In order to evaluate the effectiveness of this strengthening method,field tests using vehicles as live load were applied before and after the retrofit.The test results of deflection and concrete strain of the T-shaped beams with and without strengthening show that the capacity of the repaired bridge,including the bending strength and stiffness,is enhanced.The measurements of crack width also indicate that this strengthening method can enhance the durability of bridges.Therefore,the proposed strengthening technology is feasible and effective. 相似文献
11.
以跨度为120m的刚性拱肋柔性系杆的下承式钢管混凝土拱桥为分析模型,利用摩擦摆减震隔震支座对简支体系的桥跨结构进行减震研究,运用MIDAS有限元软件模拟多维人工地震波输入以检验摩擦摆系统的减震效果。分析结果证明了在大跨度钢管混凝土拱桥中应用摩擦摆隔震支座系统的有效性。 相似文献
12.
《天津大学学报(英文版)》2017,(5)
The construction of arch dams exhibits high uncertainty. Sensitivity analysis of construction parameters is important for the design and optimization of dam construction duration. However, current research cannot fully consider the combined influences of multiple parameters on the total construction. To effectively analyze the duration of arch dam construction, this study proposes a global comprehensive sensitivity analysis method in view of the whole process of arch dam construction based on an orthogonal experiment. This method could comprehensively consider the influence of the construction parameters that may lead to the uncertainty of construction duration. In addition, this method is able to identify the key parameters that may have a significant effect on duration uncertainty and sums up the general rules of combined parameters' interaction effect, which provides a scientific basis for reasonable optimization of the duration of dam construction. 相似文献
13.
Li Liansheng 《石家庄铁路工程职业技术学院学报》2006,(1)
介绍自上而下竖向转体拱桥的最大跨度制约因素、拱体结构形式的选择和施工工艺流程,并详细阐述自上而下竖向转体拱桥的设计与施工要点。 相似文献
14.
缪远薛怀刚李振 《福建工程学院学报》2022,(2):127-133
墨书是廊桥文化研究中的重要内容,记载着营造过程、乡俗民风、社会组织等历史信息。以闽东北寿宁地区的木拱廊桥为研究对象,对桥上梁架、檩条、柱上的墨书进行分类,梳理廊桥文化脉络,归纳墨书内容的类型及其研究价值。研究发现,墨书不仅是地方史研究的重要文献资料,也为廊桥文化履历的建档造册提供了方法依据。 相似文献
15.
ＩＮＴＲＯＤＵＣＴＩＯＮＩｔｈａｓｂｅｅｎｒｅｃｏｇｎｉｚｅｄｔｈａｔｌｏｎｇ ｓｐａｎｂｒｉｄｇ ｅｓ ,ｃａｂｌｅ ｓｕｐｐｏｒｔｅｄｂｒｉｄｇｅｓｉｎｐａｒｔｉｃｕｌａｒ,ａｒｅｓｕｂｊｅｃｔｔｏｔｈｅｄｙｎａｍｉｃｗｉｎｄａｃｔｉｏｎ .Ｔｈｅａｅｒｏｄｙ ｎａｍｉｃｓｔａｂｉｌｉｔｙ (ｆｌｕｔｔｅｒ)ｏｆｓｕｓｐｅｎｓｉｏｎｂｒｉｄｇｅｓｄｕｒｉｎｇｅｒｅｃｔｉｏｎｉｓａｓｕｂｊｅｃｔｏｆｍａｊｏｒｃｏｎｃｅｒｎｆｏｒｒｅｓｅａｒｃｈｅｒｓａｎｄｅｎｇｉｎｅｅｒｓ .Ａｌｔｈｏｕｇｈｔｈｅｐｅｒｉ… 相似文献
16.
张红岩 《石家庄铁路职业技术学院学报》2006,5(2):44-46
高速公路跨线刚拱桥的主拱圈施工中，一般采用支架现浇施工．施工单位需要使用大量的支架，并且需要制安拱架及模板、等载预压、吊装等施工工序．施工时闻长，效率低下．为了降低施工成本、缩短施工时阅，设计土模施工方案．在原始地面制作土牛拱胎并在胎顶做稳定复合土垫层，将瞬时沉降量按预拱度处理，可以省去上面四道工序．通过工程实践，土膜法施工简便，经济省时． 相似文献
17.
Zhang Hongyan 《石家庄铁路工程职业技术学院学报》2006,(2)
高速公路跨线刚拱桥的主拱圈施工中,一般采用支架现浇施工。施工单位需要使用大量的支架,并且需要制安拱架及模板、等载预压、吊装等施工工序。施工时间长,效率低下。为了降低施工成本、缩短施工时间,设计土模施工方案。在原始地面制作土牛拱胎并在胎顶做稳定复合土垫层,将瞬时沉降量按预拱度处理,可以省去上面四道工序。通过工程实践,土膜法施工简便,经济省时。 相似文献
18.
陈铁冰 《深圳职业技术学院学报》2005,4(2):16-19
考虑几何非线性，应用弹性一塑性铰分析模型进行材料非线性分析，研究了高层钢框架结构弹塑性稳定问题。研究表明，所采用的方法可以追踪个别杆件进入塑性到结构整体失稳的全过程，确定出钢框架极限承载力。 相似文献
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20.
以福鼎山前大桥空间有限元模型为基础,分析了影响钢管混凝土组拼管拱面外屈曲的主要参数,包括横撑布置形式、横撑刚度、拱脚约束情况、截面含钢率和混凝土弹性模量.有限元分析结果表明,横撑布置形式、横撑刚度和截面含钢率对钢管混凝土组拼管拱面外屈曲影响很大,但混凝土强度等级和拱脚约束对其影响很小. 相似文献