Analysis of buried pipeline response subjected to underground blasting with consideration of soil-pipe interaction

다국어 초록 (Multilingual Abstract)

The objective of this research is to record ground motions (displacements, velocities and accelerations) and analyze the stresses on a buried pipeline induced by underground blasts. The validity of the developed methodology is verified by comparing with the previous experimental results. In addition, several particle velocity prediction equations will be reviewed. The pipe stress data are used to develop safe blasting criteria for buried pipelines.Normally, the ground shock motions induced by underground blasts are of major concerns to designers in mining, construction and defense engineering. The ground shocks are usually measured by the peak particle velocity (PPV) which is considered the best measure of damage potential. Up to the present, the seismic analysis and behavior of buried pipelines have been experimentally investigated by many researchers and organizations. There have been various empirical formulae exist for the prediction of PPV as a function of the scaled distance (SD) for given geological site conditions. The seismic response analysis of buried pipelines is somewhat complex since it considers the three-dimensional (3D) dynamic behavior of the soil-pipeline interaction under blasting excitations. Thus, simplified methods are developed to obtain reliable response characteristic of the pipeline under the blast loads. In the scope of this research, several FE analyses are conducted to determine ground vibration quantities at the ground and surrounding the pipelines. Numerical models of buried pipelines and surrounding soil in FEM code are divided into two main groups with variety of explosive configuration, namely, single charge and multiple parallel charges. The maximum pipe stresses induced by the blasts are computed in the circumferential and longitudinal directions. In addition to the pipe stress and ground motion results, extensive discussions on delays are also presented to get the optimal delay of multiple blasting. The results of analysis utilized to develop safe blasting criteria for buried pipelines with the need to protect it from blast damage. As a result of the research, improved prediction of safety scaled distance will be derived with single and line sources detonated in soil.