薄壁曲线箱梁剪滞效应的计算方法

采用薄壁曲线箱梁剪力滞基本微分方程的齐次解作为曲箱梁单元的位移模式，利用刚度法与功能原理，分别导出了曲线箱梁进行有限段法分析的单元刚度矩阵和荷载列阵，编制了计算程序，对薄壁曲线箱梁的剪滞效应进行了计算，指出有限段法的精度可以满足实际工程的要求。     

无伸缩缝曲线箱梁桥剪力滞效应有限段法分析与试验研究

制作了一个三跨混凝土曲线箱梁桥模型,基于合理的试验流程安排,进行多工况下的普通连续曲线箱梁桥和无伸缩缝连续曲线箱梁桥的剪力滞效应试验,得到两种桥型在试验工况下的剪力滞系数。通过有限段法结果与有限元法、试验数值的比较,进一步验证了基于有限段法分析的本文程序计算多跨无伸缩缝曲线箱梁桥的适用性和准确性。     

基础梁与层状地基共同作用分析的新方法

本文采用样条有限点法、样条子域法分析基础与地基相互作用问题，建立新的计算格式，为基础梁与地基共同作用问题分析提供了一个经济有效的计算工具。     

基础梁与层状地基共同作用分析的新方法

本文采用样条有限点法、样条子域法分析基础与地基相互作用问题，建立新的计算格式，为基础梁与地基共同作用问题分析提供了一个经济有效的计算工具。     

智能混凝土梁的样条有限点法研究与应用

通过智能混凝土梁的计算假定,根据智能结构的位移模式、几何方程和本构关系,以变分原理和三次样条插值函数为基础,研究了智能混凝土梁的结构计算模式,在此基础上通过算例,验证了智能混凝土梁结构受力样条有限点法分析的可行性。     

箱形梁桥剪滞效应分析

本文应用变分法和有限条法分析箱形梁桥的剪滞效应。变分解法是一种不需要使用计算机的实用方法,适用于解各种支承的箱形梁包括有限条法难以求解的箱形结构。本文还运用迭加原理,对连续梁等超静定箱梁提出比较简捷的计算方法。 应用上述两种方法,探讨了箱形梁桥剪滞效应随桥的截面几何特性、跨宽比、支承条件,以及荷载型式等因素变化的影响。最后通过模型试验,验证了理论分析。     

剪力滞对超静定箱梁结构性能的影响分析

提出一种考虑梁弯曲与剪力滞变形耦合影响的分析箱梁剪力滞效应的有限元方法,导出相应的有限单元公式。在此基础上,首先分析简支静定箱梁的剪力滞系数和考虑剪力滞影响的梁的挠度,并与相应的变分法解析结果作对比,然后分析超静定连续箱梁的剪力滞系数,将其结果用叠加法和系数矩阵法结果进行验证。最后分析剪力滞对超静定多跨连续箱梁内力及变形的影响。结果表明:剪力滞对静定和超静定箱梁变形及截面应力重分布的影响较大;剪力滞对超静定箱梁内力重分布的影响很小,可以在设计计算中忽略不计。     

波形钢腹板组合箱梁剪力滞及剪切变形分析模型

为分析波形钢腹板组合箱梁的应力及变形,提出了考虑轴向平衡条件、翼板剪力滞效应和腹板剪切变形的分析模型.在位移场中增加截面纵向位移考虑轴向平衡条件.分别引入剪力滞强度函数及截面转角,以俘获剪力滞效应及剪切变形.采用虚功原理建立组合箱梁分析的控制微分方程,进而推导位移变量的解析表达式.利用三维有限单元模型的结果验证文中提出...     

连续箱梁曲桥的有限条分析法

本文用以有限条和力法为基础的数值法分析连续箱梁曲桥,采用两节线的低阶有限曲条和三节线的高阶有限曲条建立方程。作为实例,给出两座连续箱梁曲桥的分析,并将两种曲条法得出的结果同有限直条法的结果进行了比较。表明,曲条法可以用来处理箱梁直桥;而用直条法处理曲桥时,将低估桥内缘的应力和弯矩值。尽管高阶曲条法给出的条元界面的径向应力和弯矩一般较为平滑,但两种曲条法所得的全部结果都相互吻合良好。文中还讨论了模拟柱-隔板式支承系统的几种方法,表明,只要对支承截面中几个特定点的竖向位移加以约束,就足以模拟整个支承系统。     

混凝土箱梁桥剪力滞研究现状与发展

随着我国城市化进程和西部大开发的不断推进,大跨径、宽箱梁桥和曲线箱梁桥在实际工程中得到越来越多的关注,混凝土箱梁桥的空间受力性能问题也开始变得越来越突出,而其中剪力滞效应问题则成为混凝土箱梁桥应用中需要重点研究的内容。对当前普遍采用的剪力滞分析理论进行了介绍和比较,对剪力滞效应研究中的主要模型试验内容及结论进行了综述,并对目前实际工程中采用的主要剪力滞分析方法进行了评述,最后指出了目前箱梁剪力滞研究的主要方向,包括剪力滞综合理论和分析方法的建立、负剪力滞和曲线箱梁剪力滞研究。     

用三次B样条进行旋转壳有限元分析

本文成功地应用三次B样条对旋转壳进行了静力有限元分析。在本法中,壳体中面一点位移的三个分量及子午线方向的几何形状均用以三次B样条为基样条的样条函数来逼近。同一般的有限元分析相比较,本法具有多项式次数低、自由度少而连续性强、精确度高,计算速度快,内存小,方便经济等优点。     

Spline finite strip analysis of prestressed concrete box-girder bridges

The analysis of prestressed box-girder bridges using the spline finite strip method is presented. In the present study, the spline finite strip method is modified by using the non-periodic B-spline interpolation. In the analysis of the prestressed box-girder bridges, the short-term losses of prestressing are considered and each tendon force at the tendon point is evaluated by summation of the adjacent segment forces. Once the equivalent forces acting on the structure at the tendon points are found, they are transformed into statically equivalent forces at the adjacent node of nodal line. Several examples were analyzed to verify the performance of present method. Good agreements were obtained when compared with the previous studies.     

Linear elastic isoparametric spline finite strip analysis of perforated thin-walled structures

This paper describes the application of the isoparametric spline finite strip method to the linear elastic analysis of tri-dimensional perforated folded plate structures. The general theory of the isoparametric spline finite strip method is introduced. Kinematics assumptions and the procedure for combining in-plane (membrane) and bending effects are set out. Particular attention is paid to the procedure for rotating the stiffness matrix and load vector from local to global coordinates. The reliability of the method is demonstrated by comparisons with finely meshed finite element analysis results. Square stiffened perforated plates in compression and bending are analysed.     

Elastic buckling analysis of perforated thin-walled structures by the isoparametric spline finite strip method

This paper presents the application of the isoparametric spline finite strip method to the elastic buckling analysis of perforated folded-plate structures. The general theory of the isoparametric spline finite strip method is introduced. The kinematics assumptions, strain–displacement and constitutive relations of the Mindlin plate theory are described and applied to the spline finite strip method. The corresponding matrix formulation is utilised in the equilibrium and stability equations to derive the stiffness and stability matrices. A number of numerical examples of flat and folded perforated plate structures illustrate the applicability and accuracy of the proposed method.     

Post-local-buckling of fiber-reinforced plastic composite structural shapes using discrete plate analysis

In this paper, post-buckling of rectangular composite plates rotationally restrained at the longitudinal unloaded edges and subjected to end shortening strain at the simply-supported loaded edges is analyzed using the first-order shear deformation plate theory-based spline finite strip method, and its application to post-local-buckling of fiber-reinforced plastic (FRP) composite structural shapes is illustrated with discrete plate analysis. Two cases of elastically- and rotationally-restrained plates are analyzed using the spline finite strip method: rotationally-restrained along both the unloaded boundary edges (RR) and one rotationally-restrained and the other free along the unloaded edges (RF). The two cases of rotationally-restrained plates (i.e., the RR and RF plates) are further treated as the discrete plates of closed and open section FRP shapes, and by considering the effect of elastic restraints at the joint connections of flanges and webs, post-local-buckling of various FRP shapes under end shortening is studied. The numerical comparisons with the finite element modeling demonstrate that the proposed discrete plate analysis technique and spline finite strip method can be used as an efficient and valid tool for post-local-buckling analysis of FRP shapes.     

Buckling of thin flat-walled structures by a spline finite strip method

A method of buckling analysis of thin flat-walled structures of finite length subjected to longitudinal compression and bending, transverse compression as well as shear is described. The analysis uses the spline finite strip method and allows for boundary conditions other than simply supported ends as required in the semi-analytical finite strip method of buckling analysis.Convergence studies with increasing numbers of section knots are described for plates in compression, bending and shear, and for long columns with different support conditions subjected to compression. A buckling analysis of a stiffened plate subjected to compression and shear is compared with results from a finite element analysis.     

预应力混凝土连续宽箱梁偏载系数研究

以南通通启路高架工程的预应力混凝土单箱多室连续宽箱梁桥为背景,建立实体单元空间有限元模型,将箱梁跨中截面各位置点的正应力增大系数计算值与常用简化计算方法所得值进行对比,探讨简化计算方法的可行性,供同类工程设计参考。     

Static and free vibration analysis of variable-depth bridges of arbitrary alignments using the isoparametric spline finite strip method

The isoparametric spline finite strips for shells are employed to solve static and free vibration problems of variable-depth bridges of arbitrary alignments. Using this approach, a continuous bridge is first split up into substructures. Each substructure is modelled as an assemblage of isoparametric spline finite strips. Compatibility between substructures is ensured by suitable transformation at the interface. The presence of support diaphragms and bearings can also be accounted for. This method retains the computational efficiency of the spline finite strip method while it is much more flexible in geometric modelling. Solutions of this method are compared with other available solutions, and good agreement is observed.     

差条法在箱梁空间分析中的应用

有限元法和有限条法都可用于箱梁的空间分析。但是 ,有限元法计算量庞大。有限条法对于简支无内横隔的箱梁来说是很有效的 ,但对于多跨连续箱梁以及有内横隔箱梁的处理是不理想的。本文作者提出的差条法为箱梁的空间分折提供了一种较为理想的方法。