Experiments and finite element analysis (FEA) conducted in 2002 confirmed that a 1-meter-diameter circular structure constructed of 3.2 mm-thick corrugated steel plates detonated with a 155 mm shell (equivalent to 15 lbs of TNT) on top of the structure resulted in downward deformation of the ceiling. In contrast, a 400 mm-thick concrete structure under the same conditions would experience extensive cracking and backside rupture, resulting in the scattering of debris, potentially causing serious damage to personnel and equipment.

In conclusion, corrugated steel plates are processed with a thin but consistent corrugation profile, resulting in a circular or arched structural cross-section. Therefore, when appropriate cover conditions are secured, they can provide superior protection performance compared to concrete structures.

Military protective structures are sometimes designed to protect against bombs penetrating the structure and exploding internally. Critical facilities, in particular, are often designed for direct penetration. However, most general military facilities are designed for protection against near-end explosions, primarily for economic reasons.

When an explosion occurs on the surface, a blast wave and debris are generated. Of these, the blast wave, which can be quantitatively predicted, is generally used as a key design variable. The blast effect is categorized into "blast overpressure" and "impulse," and depending on the situation, either of these is applied as a design criterion.

In contrast, when an underground explosion occurs, a "crater" is formed depending on the explosion depth, and "ground shock" acts as the dominant load, rather than the blast effect, affecting the structure. Even under the same explosion distance conditions, the "tamping effect" can significantly increase the impact of an underground explosion on a structure.

Corrugated steel ECM offers the advantage of allowing for more economical construction of thicker backfill compared to concrete ECM. Therefore, whether a surface or underground explosion occurs, the primary load transmitted to the structure is ground shock. Therefore, it is crucial to design the structure around ground shock loads, considering its resistance to blast loads.