单一节理边坡模态及谐响应分析  

Study on Resonance Characteristics of Single Joint Slope

作　　者：王秒[1] 李海波[1] 刘亚群[1] 宋全杰[1] 姜军港 

机构地区：[1]中国科学院武汉岩土力学研究所岩土力学国家重点实验室,湖北武汉430071

出　　处：《水电能源科学》2014年第1期48-51,115,共5页Water Resources and Power

基　　金：国家杰出青年科学基金项目(51025935);国家自然科学基金项目(51174190)

摘　　要：为有效避免地震作用下边坡的共振现象,将含有控制结构面的顺层边坡简化为单一节理边坡模型,采用ANSYS软件对简化模型进行模态分析和谐响应分析。结果表明,随着节理结构面剪切刚度的增大,边坡的一阶振型由沿结构面的错动振动变为水平振动,且临界剪切刚度为0.5 GPa/m。当边坡岩石弹性模量由20GPa增加到50 GPa时,临界剪切刚度增加。地震作用下只有边坡的第一阶自振能被激发产生水平方向共振现象,结构面的存在能减小边坡的一阶自振频率,使边坡的自振频率更接近地震波的主频,更易产生共振,可通过支护方式增加边坡节理剪切刚度来控制地震作用下边坡的共振现象。In order to avoid the resonance of slope under the action of seismic, ideal joint rock slope was studied to discuss the natural vibration and resonance characteristics of the structural surface slope by modal analysis and harmonic response analysis module in ANSYS software, The results show that with increase of the shear stiffness of joint structural surface, the first vibration mode turns from slide vibration along the structural plane to horizontal vibration, and the threshold value is 0.5 GPa/m; the threshold value increased with elastic modulus of the slope rock changed from 20 GPa to 50 GPa; only the first natural frequency can be excited the resonance phenomenon in the horizontal direction under the seismic load. Therefore, the joint slope is more easily to be excited resonance under earthquake load because of the first natural frequency of joint slope is smaller than homogeneous slope. The resonance phenomenon of the slope is controlled with the reinforcement which can increase the slope joints stiffness under seismic load.

关 键 词：节理边坡 自振特性 模态分析 谐响应分析 共振 

分 类 号：TU452[建筑科学—岩土工程]