共查询到19条相似文献，搜索用时 296 毫秒
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基于ABAQUS大型有限元分析软件,建立了桩基厚承台非线性有限元分析模型.运用所建立的模型,对5个空间钢构架混凝土承台进行了非线性有限元分析,计算值与试验值吻合得较好,表明所建立的有限元计算模型可较好地模拟空间钢构架混凝土承台的性能;分析了空间钢构架混凝土承台内部完整的力流分布,探讨了空间钢构架混凝土承台的受力机理,为空间钢构架混凝土承台传力模型的建立提供了理论计算依据.在理论分析和以往研究的基础上,提出了空间钢构架混凝土承台的桁架模型. 相似文献
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采用试验研究和理论分析相结合的方法,对外贴碳纤维布加固的钢筋混凝土受弯梁进行了分析和研究。在介绍钢筋混凝土加固非线性有限元分析理论基础上,选择合适的材料单元(其中混凝土选用SOLID65单元,钢筋选用LINK8单元,接触单元选用TARGE170和CONTA174,碳纤维布选用SHELL41单元),设定正确的模拟参数,建立合理的非线性有限元梁模型。通过对比研究发现,有限元分析结果与试验结果吻合较好,并从弹塑性理论和有限元理论两个角度详细科学的描述了两者之间产生差异的原因。 相似文献
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根据方钢管混凝土框架在低周反复荷载下的非线性分析理论.通过ANSYS建立了方钢管混凝土组合框架的三维非线性有限元分析模型,得出了方钢管混凝土框架的理论滞回曲线,与现有试验结果对比较为吻合,为方钢管混凝土框架结构的有限元研究提供了依据. 相似文献
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分析了群桩基础桩-土相互作用的主要特征,对三维问题进行分析并简化,建立桩-土非线性作用问题的有限元求解模型,并对不同工况进行数值计算。根据数值模拟计算所得位移、应变和应力结果,分析不同荷载组合下基桩受力特点和承台受力变形特征,为群桩基础设计考虑土与基础结构协调作用提供依据。 相似文献
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有限元法在钢混结构非线性分析中的应用 总被引：1，自引：0，他引：1
有限元法在钢筋混凝土结构非线性分析中,充分体现了它"全过程仿真"的特点,和传统的线弹性分析及常规计算模型相比,它的适应性更强,力学概念更加明确,分析过程更加精确。由于钢筋混凝土结构的特点及其非线性理论的发展和完善,使有限元方法在解决混凝土的破坏准则、本构模型、钢筋与混凝土之间的关系模型、裂缝问题以及过程分析的计算机程序实现等问题中得到广泛应用,具有广阔的发展前景。 相似文献
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进行3根冷弯薄壁方钢管混凝土简支梁在循环荷载作用下的试验,在确定冷弯薄壁方钢管混凝土简支梁本构关系模型的基础上,采用有限元软件ANsYs对冷弯薄壁方钢管混凝土简支梁的滞回性能进行非线性分析。研究其在不同参数下的滞回性能、延性等重要抗震性能指标。得到的主要结论如下：（1）冷弯薄壁方钢管混凝土简支梁的滞回曲线呈梭形,较为饱满,没有出现明显的捏缩现象,表明构件具有较好的延性和耗能能力。（2）建立的非线性有限元模型能够预测冷弯薄壁钢管混凝土梁的弹塑性行为和抗震性能,计算结果与实测结果基本吻合,为进行冷弯薄壁钢管混凝土梁的数值模拟提供参考。 相似文献
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采用有限元分析软件ANSYS对先张法预应力混凝土简支梁施工阶段进行数值模拟分析。结果表明,ANSYS有限元分析计算值与理论值吻合较好,为预应力混凝土结构的分析提供了较好的途径和方法。教学实践表明:有限元数值模拟分析补充、丰富了教学内容,对常规教学方式提供一种思路。 相似文献
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用有限元软件ANSYS对一简支组合梁进行材料非线性的计算和分析,计算中混凝土除具有非线性的本构关系外,还通过破坏准则考虑了混凝土的开裂和压坏等特性。计算得到的承载力与按求塑性极限承载力的方法计算的吻合较好,这为今后进一步研究组合梁的受力特性奠定了基础。 相似文献
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Wan-huan Zhou Ren-peng Chen Lin-shuang Zhao Zheng-zhong Xu Yun-min Chen 《浙江大学学报(A卷英文版)》2012,13(11):888-894
In this paper, a semi-analytical method for the analysis of pile-supported embankments is proposed. The mathematic model describes the cooperative behavior of pile, pile cap, foundation soil, and embankment fills. Based on Terzaghi??s 1D consolidation theory of saturated soil, the consolidation of foundation soil is calculated. The embankments with two different types of piles: floating piles and end-bearing piles are investigated and discussed. The results of axial force and skin friction distributions along the pile and the settlements of pile-supported embankments are presented. It is found that it takes a longer time for soil consolidation in the embankment with floating piles, compared with the case using end-bearing piles. The differential settlement between the pile and surrounding soil at the pile top is larger for the embankment with end-bearing piles, compared with the case of floating piles. 相似文献
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采用三维数值方法,建立长短桩、变径桩双桩模型,通过大量的数值计算,分析桩顶荷载水平、桩距径比、不同桩长、桩端土模量比及不同桩径对相互作用系数的影响。分析表明,在线弹性变形阶段,桩-桩相互作用系数近似为恒定值,与桩顶荷载水平无关,进入塑性变形之后,则逐渐减小直至极限状态时趋于0;长短桩桩长比及桩端土模量比对短桩-长桩相互作用系数影响大,而对长桩-短桩相互作用系数影响小;变径桩相互作用系数仅与受荷桩桩径有关;并提出了针对长短桩、变径桩的简化计算公式,为实际工程提供参考。 相似文献
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Taper angle is one of the effective methods to reduce the dragload and downdrag of piles under the surcharge load. The model tests on the tapered pile and uniform cross-section pile embedded in sand were carried out under the surcharge load. The values of dragload and downdrag of piles versus the surcharge loads were measured. Based on the concentric cylinder shearing theory, a simplified theoretical model for calculating the dragload and downdrag of tapered piles with small taper angles under the surcharge load was proposed considering the angle effect. The correctness of the developed theoretical model was validated through comparing with the model test results obtained in this study and previous literature. Then the parametric studies of the taper angle, surcharge, strength and modulus of soil were discussed. It is shown that the tapered pile with the taper angle of 3° can reduce approximately 65% of the maximum dragload value and 30% of the downdrag value compared with a uniform cross-section pile. The value of downdrag can be decreased by approximately 50% compared with a uniform crosssection pile in the same average pile diameter. 相似文献
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曾锦秀 《福建工程学院学报》2021,(6):548-544
基于上限法、平面刚架理论与弹性地基梁理论,对双排桩加固边坡中结构变形进行解析,通过数值模拟验证所提方法的合理性,研究了影响双排桩桩身位移的6 个因素。结果表明:当连系梁厚度/ 桩径小于0.7、嵌固段与受荷段长度之比小于0.8、桩径小于1.0 左右时,对桩身位移影响较大,且呈现出明显的非线性特征?桩身弹性模量对双排桩桩身位移同样具有较大影响,但表现出近似线性的特征。对于双排桩加固边坡,可适当增大连系梁厚度、嵌固段长度、桩径、桩身弹性模量或联合注浆改善桩周岩土体的力学性能。研究结果可为边坡中双排桩的设计提供参考。 相似文献
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GAO Xiao-juan WANG Jin-chang ZHU Xiang-rong 《浙江大学学报(A卷英文版)》2007,8(7):1110-1117
As a special geological phenomenon, the character of collapsible loess foundation is collapsible when penetrated by water. This character leads to the soil losing load bearing capacity largely and may lead to foundation failure. Pile is a popular foundation used in collapsible loess. The squeezed branch and plate pile is a new type of pile developed in recent years and has not be used in a project before. In this paper three squeezed branch and plate piles are tested in collapsible loess after immersion processing. The results may be used for reference in similar construction project, and to provide theoretical references for de- signing of the squeezed branch and plate piles in engineering practice. 相似文献
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林光忠 《福建工程学院学报》2018,(1):13-16
在建的福建省龙岩市红坊互通立交建设区域属于岩溶极为发育地区,桥梁桩基沉降量计算的准确度直接影响到该工程的安全性和经济性。采用FLAC3D有限差分软件进行数值模拟分析,得到6种桩径的桩基位移情况。经过与其它3种用设计规范计算得到的数值比较,发现用有限元数值模拟的结果与按《建筑桩基规范》计算的结果很接近,并对其进行原因分析。 相似文献
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Bearing Behaviors of Stiffened Deep Cement Mixed Pile 总被引：1，自引：0，他引：1
A series of investigations were conducted to study the bearing capacity and load transfer mechanism of stiffened deep cement mixed (SDCM) pile. Laboratory tests including six specimens were conducted to investigate the frictional resistance between the concrete core and the cement soil. Two model piles and twenty-four full-scale piles were tested to examine the bearing behavior of single pile. Laboratory and model tests results indicate that the cohesive strength is large enough to ensure the interaction between core pile and the outer cement-soil. The full-scale test results show that the SDCM piles exhibit similar bearing behavior to bored and cast-in-place concrete piles. In general, with the rational composite structure the SDCM piles can transmit the applied load effectively, and due to the addition of the stiffer core, the SDCM piles possess high bearing capacity. Based on the findings of these experimental investigations and theoretical analysis, a practical design method is developed to predict the vertical bearing capacity of SDCM pile. 相似文献
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This work presents a new analytical method to analyze the influence of reaction piles on the test pile response in a static load test.In our method,the interactive effect between soil and pile is simulated using independent springs and the shear displacement method is adopted to analyze the influence of reaction piles on test pile response.Moreover,the influence of the sheltering effect between reaction piles and test pile on the test pile response is taken into account.Two cases are analyzed to verify the rationality and efficiency of the present method.This method can be easily extended to a nonlinear response of an influenced test pile embedded in a multilayered soil,and the validity is also demonstrated using centrifuge model tests and a computer program presented in the literature.The present analyses indicate that the proposed method will lead to an underestimation of the test pile settlement in a static load test if the influence of the presence of reaction piles on the test pile response is neglected. 相似文献
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简洪钰 《福建工程学院学报》2005,3(1):8-12
采用双曲线法、调整双曲线法和指数法对某小区住宅楼3根试验桩的静载试验结果进行单桩极限承载力预测，并将预测结果与理论计算结果进行对比，分析结果表明：盲目套用《建筑桩基技术规范》JGJ94-94中有关预制桩承载力指标来计算桩的极限承载力是不科学的，其指标也不适合小截面静压预制桩。结合桩基施工终压力和每延米压桩耗能的对比分析，表明桩的竖向极限承载力与终压力存在一定的比例关系但与压桩耗能不存在比例关系。 相似文献