作　　者： (翟志明）; (杨冬英）; (龚志超）;

机构地区： 苏州科技大学土木工程学院,江苏苏州215011

出　　处： 《广西大学学报（自然科学版）》 2017年第4期1431-1440,共10页

摘　　要： 为了研究饱和土中考虑施工效应时管桩的纵向振动特性,基于饱和多孔介质理论,首先建立了纵向动荷载下受施工影响时饱和土中饱和土—管桩的纵向耦合振动力学模型,然后利用Laplace变换得出饱和土频域内振动方程,并对饱和土动力方程进行数学解析求解,同时结合边界条件和初始条件进行饱和土—管桩耦合振动方程解耦计算,获得管桩的频域内纵向振动频域解析解,利用傅里叶逆变换得出管桩时域内半解析解,最后分析管桩施工造成的挤密、松弛效应以及土中孔隙水等因素对薄壁管桩动态特性的影响,获得了饱和土中能够合理考虑施工效应影响的管桩振动结论:施工效应会导致剪切波速比例系数变化,当剪切波速比例系数越小,则在同一共振频率处动阻尼和动刚度曲线的振幅越大;饱和土中水的体积分数变大会使得桩顶速度导纳和反射波曲线振幅变大。 To study the longitudinal vibration of pipe pile regarding the construction effects in saturated soil,a longitudinal coupled vibration model of saturated soil-pile which considered the construction effects was established under vertical dynamic loads based on the saturated porous medium theory. Then,the vibration equation of the frequency domain of saturated soil was obtained by the Laplace transform. After applying the boundary and initial conditions to solve the dynamic equation,the analytical solutions in the frequency domain were obtained. Next,the semi-analytical solution of the pipe pile and saturated soil in time domain was derived by the inverse Fourier transform. Finally,the influences of compaction,relaxation,volume ratio of pore water and other major factors which affected the dynamic characteristics of the pipe pile were analyzed to obtain thereasonable pipe pile vibration theory considering the construction effects. The construction effect can lead to the shear wave velocity ratio change,and when the shear wave velocity ratio is smaller,the amplitude of the dynamic damping and dynamic stiffness will be larger at the same resonance frequency; the volume fraction of the water in saturated soil changes the amplitude of the head velocity admittance and the reflection wave curve.

关 键 词： 饱和多孔介质 管桩 施工效应 桩动力响应