首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到19条相似文献,搜索用时 546 毫秒
1.
章给出了考虑剪力影响对梁的弹性曲线微分方程,并结合用积分法计算有剪力作用时梁的挠度,讨论了剪力对梁的挠度的影响。指出:当梁截面的剪应力分布系数k值较大和梁长度较短时,剪力对梁挠度的影响不可忽略。  相似文献   

2.
基于挠度与应力等效原则,将作用于连续配筋混凝土路面(CRCP)中央的车辆集中荷载通过傅里叶级数展开为等效的半波正弦荷载.在荷载转换和小挠度弹性薄板理论的基础上,提出了车辆集中荷载作用下脱空地基上CRCP的挠度和应力计算公式,分析了参数的敏感性.结果表明:板的最大挠度与车辆集中荷载、板的宽度成正比,与板的横向弯曲刚度、板...  相似文献   

3.
通过克尔(Winkler)假设推导出来的弹性地基梁的计算公式,详细计算了有限长柱下条形基础梁在受特殊荷载作用下的位移、内力和基底反力分布,并把计算结果与刚性设计法的计算结果进行了比较,得出了结论.  相似文献   

4.
文章介绍了一种快速、准确、直观的弹性地基梁静态响应分析方法。首先将文克尔地基模型表达的弹性地基梁曲线微分方程改写成含有四个变量的试函数;其次应用无网格有限体积法,采用Matlab语言编写程序,计算弹性地基梁在外载荷作用下的扰度、转角、弯矩和剪力;最后根据用户输入的条件参数,以图形方式输出结果。  相似文献   

5.
现浇混凝土空心板两个方向的刚度存在差异,在确定了这种差异的大小后,才能明确其正交异性亦或是各向同性.本文应用弹性力学中的里茨法,结合空心板两向刚度计算公式,分析给出现浇混凝土空心板弹性挠度计算公式,并与PKPM软件结果进行对比,验证公式的准确性.  相似文献   

6.
弹性地基上四边自由矩形大挠度薄板的自由振动   总被引:1,自引:0,他引:1  
考虑具有粘滞阻尼的Winkler地基上四边自由受简谐激励的矩形板的偏微分方程组,找到了满足所有边界条件的近似挠度函数,利用Galerkin方法把偏微分方程表示的非线性动力学方程转化为用常微分方程表示的非线性动力学方程。在KBM法的基础上,引入谐波平衡的观点研究了弹性地基上四边自由无阻尼矩形板自由振动,应用Hamiltonion函数研究了系统能量与周期的关系。  相似文献   

7.
基于Reddy三阶剪切变形理论,研究了功能梯度材料梁的线性弯曲问题,假设功能梯度材料性质只沿梁厚度方向变化,且服从幂函数规律,推导了问题的控制方程,考虑固支边界条件,并选用合适的计算结构,用微分求积法对其进行数值求解.利用数值结果考察了材料的梯度性质,载荷条件、细长比等对梁弯曲行为的影响.结果表明:相同条件下,FGM梁的挠度介于纯金属和纯陶瓷之间,并且随着梯度参数的增加,挠度在减小;随着FGM梁的细长比的增大,梁中心挠度迅速减小.  相似文献   

8.
目前,越来越多的平面结构采用钢筋混凝土井字梁形式,该结构体系具备能形成大空间、装修美观、梁截面小、空间利用率高、受力合理等特点,经过一定结构设计实践,对井字梁配筋、边梁配筋、边梁扭矩值和弹性最大挠度值进行分析后,阐述井字梁的设计要点与计算特征。  相似文献   

9.
碳纤维增强混凝土构件的力学性能研究   总被引:2,自引:0,他引:2  
本文针对碳纤维增强混凝土抗压、抗拉强度和碳纤维复合材料棒材(C-BAR)增强混凝土梁的裂缝及挠度等问题,通过对试验结果的分析和对比,给出了相关的数据和计算公式,为碳纤维增强混凝土在工程中的应用以及试验结果的预报提供了必要的参考  相似文献   

10.
弹性荷载法用于作结构的线位移图,比之共轭梁法的应用范围要广。对于具体的结构,若导出弹性荷载的实用计算公式,就更便于应用。本文仅对方法的基本理论进行如下一些讨论。一、论证方法若给出链条(图1a)和链条位移图(图1b)以及虚梁(图2a)和虚梁弯矩图(图2b)的完整图形,由此出发去论证,可以对弹性荷载法的实质和弹性荷载的计算更明确地加以说明。  相似文献   

11.
两种或多种不同材料制成的组合梁是工程实际中的一种常用结构。本文基于材料力学中的平面假设、胡克定律等基本假设和概念,给出了组合梁组合变形分析的一种通用解法,建立轴力、弯矩与拉伸位移和弯曲挠度的关系,推导出拉伸位移和弯曲挠度满足的微分方程。该分析方法简单易懂,适合材料力学教学和工程实际应用。  相似文献   

12.
Nonlinear bending of cantilever incompressible poroelastic beams subjected to a uniform load is investigated with the constraint that fluid flow is only in the axial direction. The governing equations for large deflection of the poroelastic beam are derived from theory of incompressible saturated porous media. Then, nonlinear responses of a cantilever beam with impermeable fixed end and permeable free end are examined with the Galerkin truncation method. The deflections and bending moments of the poroelastie beam and the equivalent couples of the pore fluid pressures are shown in figures. The differences of the results between the large deflection and the small deflection theories are analyzed. It is shown that the results of the large deflection theory are smaller than those of the small deflection theory, and the time needed to approach their stationary states for the large deflection theory is shorter than that for the small deflection theory.  相似文献   

13.
Based on convolution-type constitutive equations for linear viscoelastic materials with damage and the hypotheses of Timoshenko beams with large deflections, the nonlinear equations governing dynamical behavior of Timoshenko beams with damage on viscoelastic foundation were firstly derived. By using the Galerkin method in spatial domain, the nonlinear integro-partial differential equations were transformed into a set of integro-ordinary differential equations. The numerical methods in nonlinear dynamical systems, such as the phase-trajectory diagram, Poincare section and bifurcation figure, were used to solve the simplified systems of equations. It could be seen that simplified dynamical systems possess the plenty of nonlinear dynamical properties. The influence of load and material parameters on the dynamic behavior of nonlinear system were investigated in detail.  相似文献   

14.
Based on convolution-type constitutive equations for linear viscoelastic materials with damage and the hypotheses of Timoshenko beams with large deflections, the nonlinear equations governing dynamical behavior of Timoshenko beams with damage on viscoelastic foundation were firstly derived. By using the Galerkin method in spatial domain, the nonlinear integro-partial differential equations were transformed into a set of integro-ordinary differential equations. The numerical methods in nonlinear dynamical systems, such as the phase-trajectory diagram, Poincare section and bifurcation figure, were used to solve the simplified systems of equations. It could be seen that simplified dynamical systems possess the plenty of nonlinear dynamical properties. The influence of load and material parameters on the dynamic behavior of nonlinear system were investigated in detail.  相似文献   

15.
本在对北宋三类语言材料进行穷尽性统计的基础上,对北宋疑问语气词“麽”的用法进行了描写。章认为:a.至迟到北宋,“麽”已彻底、整体完成了虚化;b.在共有的语义功能范畴内,“麽”字句在与反复句的竞争中已占上风,显示出其强大的生命力;c.“麽”确实源于“无”,从北宋的“麽”的结构特征可以看出“无”的语义特征对“麽”的影响。  相似文献   

16.
历史地分析建构主义的哲学根源   总被引:3,自引:0,他引:3  
建构主义作为一种认识论 ,其观点的形成具有深厚的哲学根源。本文按照历史的顺序 ,分析了建构主义的哲学基础及其哲学根源 ,以求从哲学的高度进一步了解其思想的历史传承与发展。因为目前 ,建构主义的“以在原有的知识经验基础上的建构为核心”的学习观 ,还有“以学生为中心”的教学论思想 ,已逐渐渗透到与教育有关的各个学科领域。这对我国探索“以培养创造性为核心”的素质教育具有可借鉴之处  相似文献   

17.
从应用力学中两个广义位移的梁的理论出发,推导出具有两个广义位移受剪切影响的压杆和梁的微分方程式,并求出其通解,进而导出其在相应边界条件下的精确解.  相似文献   

18.
儒家德治的理论基础是人性善,它的思想内容极其丰富,尤以"为政以德;贵在修身;民本思想;教而后刑,德主刑辅;尊贤使能"等最为经典。但儒家德治在今天也有其内在局限性,我们应当以辩证的观点来审视它。  相似文献   

19.
This paper presents a simple solution of the dynamic buckling of stiffened plates under in-plane impact loading. Based on large deflection theory, a discretely stiffened plate model has been used. The tangential stresses of stiffeners and in-plane displacement are neglected. Appling the Hamilton's principle, the motion equations of stiffened plates are obtained. The deflection of the plate is taken as Fourier series, and using Galerkin method the discrete equations can be deduced, which can be solved easily by Runge-Kutta method. The dynamic buckling loads of the stiffened plates are obtained form Budiansky-Roth criterion.  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