Blast Resistant Design of Under-ground Structures : A Study of the Effect of Rock Class and Rock Cover Sharma Rajani1, Kanupreiya1 1Wapcos Ltd. Online Published on 24 January, 2024. Abstract Hardened design requirements for an underground structure include: penetration and ground shock due to conventional weapon effects (CWE). In the present study, blast pressure for a conventional weapon is studied for different rock conditions and varied rock cover, for a conventional weapon detonation using formulations as per TM manual. Calculations are carried out at the overt of the secondary tunnel lining. For different ductility ratios, free field acceleration and reflected acceleration are computed using the dynamic load factor (DLF). Bending moments and axial forces are calculated using analytical methods. For economic design of tunnel lining, blast pressures over the structure can be significantly controlled by use of sacrificial structures such as buster slab. The effect of providing a buster slab and its effects on accelerations is examined. Additionally, a two dimensional equivalent static finite element analysis is carried out in Ansys using the soil structure interaction for a sample case. Results from analytical models are compared with results from numerical analysis. Top |