Abstract: Nowadays, backhoe hydraulic excavator is considered as one of the main third-party threats to the buried gas pipeline. In order to determine the dynamic impact load and dynamic load coefficient when excavator bucket tooth impacts on the pipe, full-scale static and dynamic pipe digging tests was performed. By using ADAMS software, the pipelines-soil-excavator multi-body dynamics model was established. Based on the cylinder displacement and pressure test data, the mining process was reproduced in the simulation, which requires the material properties, constraints, friction and contact, the driving force information for multi body dynamics system. Finally, the digging force in different conditions and the energy dissipation caused by the friction force between the moving parts were achieved. Thus, the energy dissipation rate of excavator under different conditions could be assessed. The research will not only provide a reliable load reference to the quantitative assessment of buried gas pipeline damage that subjected to ground impact of mining machinery, but also provide data for disaster prevention and control of third-party interference along the line.