摘要
动载荷作用引起岩石边坡失稳破坏,尤其力幅突变激扰作用对边坡稳定影响很大。对动、静载荷作用下岩石力学性质进行了分析,建立了岩石边坡非线性运动方程,分析了岩石边坡动力变形模型及非线性动力响应,得出当扰动频率增加到一定程度,滑体振幅突然增加,产生向上突跳并随力幅的增加继续增加;反之,当力幅较大并逐渐减小时,滑体振幅也随之减小,当扰动的振幅减小至一定程度,滑体振幅突然降低,产生向下突跳减小。对初始条件和力幅突变激扰对岩石力学非线性振动系统的影响进行了分析,得到初始条件的微小变化可引起系统响应的巨大差异,当振幅A极小时,线性系统的振荡很弱,它对非线性系统的作用也很弱,整个系统的运动便可看作两运动的独立叠加。当振幅A再加大到使其幅值超过非线性系统三奇点之间的间隔时,系统可以在这些奇点之间来回跃迁振荡,从而运动复杂化,随振幅A的增加,系统从倍周期运动向混运动变化,研究结果可为岩石边坡的动力稳定提供指导。
The dynamic loading leads to instability and failure of rock slope. Especially, the role of force increase mutation has a great influence on slope stability. The rock mechanical properties are analyzed under static and dynamic loadings. And then, the nonlinear equation of rock slope is established. The dynamic deformation model of rock slope and the nonlinear dynamic response are studied. The amplitude of the sliding body suddenly increase, resulting in the sudden jump up and continue to increasing with the increase of the force, when the disturbance frequency to a certain extent. Conversely, the amplitude of the landslide suddenly reduces, resulting in the sudden decreases when the perturbation amplitude reduces to a certain extent. Tiny changes in initial conditions can cause a huge difference of the system response. The movement of the entire system can be regarded as an independent superposition of the two sports when the amplitude(A) is very small. As the amplitude(A) increases to more than its amplitude between the three singular points of the nonlinear system interval, the system can oscillate back and forth between these singular points. With the amplitude(A) increasing, the system changes from the period-doubling motion to mix sports. The results can provide guidance for the dynamic stability of the rock slope.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2013年第6期1541-1545,1573,共6页
Rock and Soil Mechanics
基金
国家自然科学基金项目(No.51274122
No.50774046)
关键词
岩石边坡
力幅突变
激扰作用
动力敏感性
rock slope
force increase mutation
excitation function
dynamic sensitivity