| Double line tunnel with extra-large sections will be more and more common in the country, due to the large section, it is certain that the double line tunnel affects each other during the blasting excavation, the seismic wave produced by tunnel excavation affects the safety and stability of the surrounding rock. Based on the dynamic finite element, the mutual influence of double line tunnel with extra-large sections is analyzed by means of ANSYS/LS-DYNA software in the essay, and some useful rules and conclusions are got.The explosion theory and controlling standards of vibration in rock are first expounded in the essay. Regression analysis is performed with the data measured in the project, thus declining formulas of velocity in different directions are got, also some rules are obtained from the analysis of the velocity-time curves. The simulation principle and model of blasting excavation of tunnels are analyzed and introduced in the essay, 3D simulation of blasting excavation of the double-line tunnels with extra-large sections is performed by means of dynamic finite element ANSYS/LS-DYNA software. The rule and character of the mutual influence of blasting excavation in double line tunnel with extra-large sections are got. Dynamic effect of blasting excavation in the left line and the right line is respectively researched, the locations of velocity extreme values of different sections are studied, as well as the occurrence time and declining rule. The character of occurrence time of velocity extreme values in different directions is got, the stress of double line tunnel is also analyzed, and the occurrence time and locations of the stress extreme values are obtained.
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