成层广义Voigt地基中粘弹性桩纵向振动分析与应用

Vibration of inhomogeneous viscous-elastic pile embedded in layered soils with general Voigt model

研究了考虑桩身材料阻尼、桩侧土采用广义 Voigt模型条件下 ,成层土中不均匀桩 (截面面积或材料性质在桩长方向上存在突变 )的纵向振动特性 ,求得了瞬态半正弦脉冲荷载作用下 ,桩顶频域响应的解析解及时域响应的半解析解 ,分析了桩身材料阻尼及不同土质的桩侧土层分界面对桩顶时、频响应曲线的影响 ,得到了许多新的结论 .终将所得理论结果与实际工程桩及预制模型桩的实测曲线进行了拟合对比 ,结果表明 ,本文得到的理论成果相比于已有成果能更好地反映客观实际 .

The vibration of inhomogeneous viscous-elastic pile was studied to develop a new theory, in which surrounding layered soils are described with generalized Voigt model. In practice, many Voigt units are connected in series. Then, a series of analytical responses in frequency or time domain are obtained with Laplace transform and inverse Fourier transform on the condition of transient half cycle sin wave shaped excitation on the pile top. Based on this, several figures are prepared to illustrate the influences of pile viscosity and soil model parameters on the responses, and some important conclusions are drawn for pile integrity test. It was shown that the interfaces between adjacent soil layers had little influence on the response of the pile top and that the effects of pile viscosity on the response were different from those of damping of soil around the pile. It was proved that the new theory was better than the current one and that the theoretical curves were in good agreement with those of field measurement by three examples of matching between measured curves and theoretical curves.