THE IMPACT OF EARTHQUAKES ON THE TUNNEL FROM HANOI METRO SYSTEM WHEN THE TUNNEL HAS A HORSESHOE SHAPE CROSS-SECTION

Hanoi is capital Viet Nam. Currently, the metro system is being constructed in Hanoi. This paper uses the 2D numerical method with Abaqus software to set up the tunnel model that has a horseshoe shape cross-section of the Hanoi metro system, passing through the Hanoi center. On the basis of the data about the strongest earthquake that could occur in Hanoi center, the paper calculated the impact of this strongest earthquake to the tunnel in two case: the first case with the soil environment surrounding the tunnel that has been studied is elastic, uniform and isotropic, the second case with the soil environment surrounding the tunnel is elastic perfectlyplastic according to Mohr-Coulomb failure criterion and has a damping ratio is 5%. On the basis of the results obtained, the paper assessed and given results about the impact of the strongest earthquake that could occur the Hanoi area to the stability of the tunnel that has a horseshoe shape cross-section from the Hanoi metro system.