Abstract: According to the Biot wave theory and the complex function combined with multi coordinate method, the wave scattering dynamical equation of liquid- filled pipe in saturated soil impacted by P waves is solved. The effects of fluid property in the pipe, incident wave angle and buried depth on the distributions of dynamic stress concentration coefficient and pore pressure concentration coefficient are analyzed. The results show that, in low frequency elastic wave incidence, dynamic stress concentration coefficient and pore pressures concentration coefficient are relatively uniform distributions around the periphery of the pipe; when the incident frequency increases, the distributions become complex, but the peak values decrease. In low or middle frequency elastic wave incidence, the dynamic stress concentration coefficient and pore pressure concentration coefficient of the pipeline filled with water or oil are relatively smaller than air medium. But in high frequency elastic wave incidence the opposite is the case. When the fluid medium in pipeline is water, the influences of the incident angle and depth of pipeline on the dynamic stress concentration coefficient and pore pressure concentration coefficient are analyzed. With the increasing of incident angle, the distribution also occurs at certain angle deflection. When the incident wave is perpendicular to the pipe, the peak value of pipe dynamic stress concentration coefficient around the periphery of the pipe is relatively large. With the increasing of depth, dynamic stress concentration coefficient and pore pressures concentration coefficient show shock decrease.

Key words: saturated soil, liquid-filled pipe, P waves, dynamic stress concentration coefficients, pore pressures concentration coefficients