Analysis on Earthquake Damage Forms and Affecting Factors of Underground Cavern

According to the information about underground damage in earthquake all over the world, it is summarized that earthquake damage is caused by mountain slope failure, the collapse of cavern’s export, dislocation damage of cavern’s cross-section, great displacement along the fault intersection, spalling of surrounding rock, disturbance or deformation of the support and lining system, et. The earthquake damage factors of underground cavern were analyzed by using numerical simulation techniques. It is shown that when the earthquake intensity value is high, or the initial stress field is small, or lining stiffness is high, the underground will more easily be destroyed by earthquake. Compared with the square tunnel and horseshoe-shaped tunnel, dynamic stability of circular tunnel is better. The export of cavern is vulnerable to earthquake damage.

Reconstruction of Dewey Square Tunnel

The Dewey Square Tunnel in Boston, part of the Central Artery I-93 alignment, is to be upgraded to satisfy current highway standards. The preliminary design includes extensive structural modification. Construction staging plans include a program of inspection and material testing of the existing structure.