大连快轨3号线二阶刚度一系悬挂设计

介绍了城轨车辆转向架一系悬挂的结构设计,在设计中着重考虑车辆舒适性、安全性及可维护操作性。

PMM纤维铰在排架结构刚度折减系数取值中的运用

目前钢筋混凝土排架结构的设计多数基于弹性假定。但在实际工程中,排架结构受力常伴随着混凝土开裂,钢筋与混凝土黏结滑移等现象,而排架结构的二阶效应常使结构刚度退化进一步加重。因此,在对排架结构进行分析的过程中,对材料非线性时二阶效应的计算就显得十分必要。在工程设计中较为切实可行的方法是引入考虑刚度折减的弹性二阶分析法,其准确性很大程度取决于刚度折减系数的取值,笔者试图通过基于材料模型的PMM纤维铰找到合理的排架结构刚度折减系数。

基于滑移连接的分阶屈服金属连梁阻尼器抗震性能研究

本文提出了一种新型的基于滑移连接的分阶屈服型金属阻尼器,布设在连梁跨中构成消能连梁。主要介绍了其构造形式、耗能机理及设计方法。并利用有限元软件ABAQUS模拟,分析了其在低周往复加载下的滞回性能。结果表明:该阻尼器滞回曲线饱满,耗能性能优良,能够实现第二阶段的刚度增强,具有良好的减震效果。该阻尼器构造简单,制作方便,采用高强螺栓连接,更换方便,有广阔的工程应用前景。

New tangent stiffness matrix for geometrically nonlinear analysis of space frames

A three-dimensional beam element is derived based on the principle of stationary total potential energy for geometrically nonlinear analysis of space frames. A new tangent stiffness matrix, which allows for high order effects of element deformations, replaces the conventional incremental secant stiffness matrix. Two deformation stiffness matrices due to the variation of axial force and bending moments are included in the tangent stiffness. They are functions of element deformations and incorporate the coupling among axial, lateral and torsional deformations. A correction matrix is added to the tangent stiffness matrix to make displacement derivatives equivalent to the commutative rotational degrees of freedom. Numerical examples show that the proposed dement is accurate and efficient in predicting the nonlinear behavior, such as axial-torsional and flexural-torsional buckling, of space frames even when fewer elements are used to model a member.