非均匀地基上自由梁的刚体模态分析

ANALYSIS ON RIGID MODAL OF FREE BEAM ON INHOMOGENEITY FOUNDATION

非均匀单参数(Winkler)地基和双参数(Pasternak)地基上自由梁的刚体模态与梁体—土体间的相互作用有关,当约束或支承不影响梁的平动和转动时,相应的刚体模态则会出现.刚体模态的频率和振型随的地基的不均匀性和基床系数的变化而变化.基于哈密顿原理和变化运算,获得了考虑周围土体支承影响的双参数地基梁振动特性,并分析了不均匀地基上自由梁的广义刚体模态频率及其随地基不均性的变化规律.

The rigid modal of free beam on inhomogeneous Winkler foundation or double-parameter foundation relates to the interaction between beam and soil. When there is no constraint or the existent constraints dont influence beam＇s translation or rotation, the corresponding rigid modal will occur. In order to consider the effect of soil under and around the beam, double-parameter foundation model was introduced. Based on Hamilton principie the and calculus of variation, the vibration equation variable regularity of modal frequency and modal of beam on double-parameter foundation was deduced, and shape with the inhomogeneous foundation were analyzed.