UNDEX

The standoff distance between the explosive and the structure and the depth of the explosion are the most dominant factors in UNDEX loading.

Hence, for precise design and analysis of structures subjected to UNDEX, experimental studies on reduced scale models are invaluable.

Lagrangian-Eulerian procedures are common to get feasible results from FSI UNDEX problems.

where [p.sub.i] is the incident fluid pressure (here UNDEX overpressure and pulsations), [p.sub.s] is the scattered pressure of the structure, G is a matrix that couples structural degrees of freedom to the fluid grid, and [A.sub.f] is the matrix that stores information of areas of Lagrangian elements in fluid cells.

In most UNDEX loadings, strain rate can reach up to [10.sup.4]/s; hence, to get accurate results, an acceptable rate sensitive strength model must be used.