摘要
利用Shah和Heaviside阶跃函数描述振动压路机的动态激振作用,对上层为非饱和土,下层为饱和土的双层地基进行动力响应分析。采用三重Fourier变换求解饱和土与非饱和土的动力控制方程,推导出双层地基在变换域中的动力响应解。通过算例分析,研究了双层地基在振动压路机作用下的动力响应和参数影响规律。结果表明,压路机激振频率和名义振幅升高,地基的振动峰值将随之增大;当压路机行驶速度超过5km/h时,地基的振动峰值逐渐增大并出现波动现象,其波动幅度取决于压路机的激振频率。此外,还考虑了饱和度对土体剪切模量和渗透系数的影响。研究发现,饱和度处于S_(w0)~1-S_(w0)区间时,土体具有较大的动刚度,地基振动位移减小。
The Shah and Heaviside step functions are used to describe the dynamic excitation of the vibratory roller, and the dynamic response analysis of the double-layer foundation with the upper layer of unsaturated soil and the lower layer of saturated soil is carried out. The three-dimensional Fourier transform is used to solve the dynamic control equations of saturated and unsaturated soils,and the dynamic response solution of the double-layer foundation in the transform domain is derived. Through the analysis of numerical examples, the dynamic response of the double-layer foundation under the action of the vibratory roller and the influence of parameters are studied. The results show that the vibration peak value of the foundation will increase accordingly as the excitation frequency and nominal amplitude of the roller increase. When the speed of the road roller exceeds 5 km/h, the vibration peak value of the foundation gradually increases accompanied by fluctuation. The amplitude of the fluctuation depends on the excitation frequency of the road roller. In addition, this paper also considers the influence of saturation on soil shear modulus and permeability coefficient.The study also found that the soil has greater dynamic stiffness and the vibration displacement of the foundation decreases when the saturation is in the range of S_(w0)~1-S_(w0).
作者
王立安
张家玮
李奎奎
刘生纬
WANG Li-an;ZHANG Jia-wei;LI Kui-kui;LIU Sheng-wei(School of Civil Engineering,Lanzhou Jiaotong University,Lanzhou,Gansu 730070,China;Institute of Cultural Heritage Protection Engineering Technology,Lanzhou Jiaotong University,Lanzhou,Gansu 730070,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2021年第11期3182-3190,共9页
Rock and Soil Mechanics
基金
国家自然科学基金资助项目(No.51268031)。
