不均匀土中多缺陷桩的轴向动力响应

Dynamic axial response of multi-defective piles in nonhomogeneous soil

建立不均匀地基中多缺陷桩的动力学模型和数学模型 ,以模拟桩在低应变动测时较为一般的情况。用Laplace变换及矩阵理论 ,解析地求得桩顶速度的传递函数 ,进一步得到桩顶速度频响函数或速度导纳、桩顶速度的频谱函数和时域表达式 ;理论导纳曲线及时域曲线与工程桩动测曲线较为一致 ;

Dynamic and mathematical models of multidefective piles in nonhomogeneous soil are established,in order to simulate general behavior of a single pile which is dynamically tested at low strain.By means of Laplace transform and matrix thoery,an exact transfer function of pilesoil system is derived.Further,the mechanical admittance expression,frequency and time domain expressions of the velocity of the pile head subjected to axial impact loading are gained.The validity of this approach is verified through dynamic tests on some engineering piles in the field,and the theoretical predictions match the response of the piles.Single factor analysis method is presented for interpreting complicated mechanical admittance curves.