相邻明置刚性条形基础的水平-摇摆耦合阻抗研究

Coupled lateral-rocking impedances of adjacent rigid strip foundations rested on elastic half-space

基于弹性半空间理论研究两相邻明置条形基础的水平-摇摆耦合动力阻抗。推导了频域内水平、垂直简谐条形均布激振下弹性地基位移的格林函数,将基础与地基的接触面分割成若干个子单元,利用格林函数建立各子单元的耦合柔度方程。根据基础的刚体位移决定各子单元的位移,由叠加原理得到土与相邻明置条形基础的水平-摇摆动力耦合阻抗函数。通过收敛性研究并与其他数值计算及混合边值法的精细解进行比较,证明此方法具有计算简便和精度高的特点,可用于全频段阻抗函数的计算。最后分析了相邻条形基础距宽比对水平-摇摆耦合动力相互作用的影响,计算表明:当两明置条形基础距宽比S/L<5.0时,应考虑其水平-摇摆的动力相互作用效应。

The coupled lateral-rocking impedances between adjacent strip foundations are studied based on the elastic half-space theory. The interface between the foundations and the supporting medium is divided into a number of strip elements. Green functions of the elastic soil medium under lateral and vertical harmonic uniform excitation with infinite length are derived to establish the dynamic-flexibility matric for those strip elements. The coupled lateral-rocking impedances between soil and adjacent strip foundations are solved by adding the bending moments and the contact forces on each element, based on the fact that displacements of each element are determined by those of the rigid foundations. The accuracy is verified by the convergence and comparison studies with numerical solutions and the rigorous solution from mix-boundary-value method. The influences of the distance ratio S/L on the lateral-rocking interaction betWeen two foundations are discussed in detail. It is shown that the lateral- rocking interaction between adjacent strip foundations should be taken into consideration when S/L less than 5.0.