Nof and Paldor (Safety Sci 2010;48:607-14) suggested that resonance in the air pockets in the Indian Spring cavern might have contributed to the 1991 collapse. Here, we extend the resonance theory to one pocket in the cavern and a very broad basin that serves as the other branch of the U-tube. Our methodology is to apply familiar fluid dynamics principles to the situation that occurred in the c...

[1] An Earth tide signal at the lunar tidal period of 12 hours 25 min has been detected in the Sagnac frequency record of the C-II ring laser 30 m underground at Christchurch, New Zealand. Its amplitude, one part per million of the Earth rotation signal, is much greater than the value of 40 parts per billion expected. Tiltmeter records show that a substantial part of this amplification is geoph...

The rock masses in a construction site of underground cavern are generally not continuous, due to the presence of discontinuities, such as bedding, joints, faults, and fractures. The performance of an underground cavern is principally ruled by the mechanical behaviors of the discontinuities in the vicinity of the cavern. During underground excavation, many surrounding rock failures have close r...

The traditional Three-dimensional (3D) model for stability analysis of a large underground cavern group only includes the main powerhouse, transformer chamber, tailrace surge tank, electrical wire hall, and part diversion tunnel tailwater tunnel. Other caverns excavation are not taken into consideration, which is inconsistent with actual project. In this study, 3D Finite Element Method (FEM) mo...

Caverns are generally formed by a combination of regional geological action and groundwater, their improper treatment will inevitably lead to dangerous conditions in underground works. To detect the specific failure mechanism tunnel-surrounding rock induced invisible caverns, true triaxial compression test is conducted, accompanied acoustic emission technology an internal borehole camera, for m...

Underground TWH (Two-well-horizontal) salt caverns are an ideal storage medium for large-scale energy storage, having large usable volumes and high construction efficiency. Different tubing/oil-blanket lifting techniques relate to different solution mining rates help define cavern geometries based on the previous experience of SWV (Single-well-vertical)-cavern construction. In this study, we pr...