Analysis on explosive load

In the LIRA-FEM software, analysis on explosive load may be carried out by various methods.

Eurocodes (EN)

Analysis of structures on blast wave (explosion)

The LIRA-FEM software package implements the analysis of buildings on explosion; it includes:

automatic collection of load from blast wave;
quasi-static analysis;
analysis by the direct dynamic method.

Automatic collection of load from blast wave

Generating the explosive load using the "Explosion" node

In the LIRA-CAD module with the help of the Explosion node, it is possible to automate all processes related to determining the intensity of the explosive load and its application to the relevant structural elements. Various explosion parameters are considered: mass of the charge, location of the explosion (in the air or on the surface), the step for approximation of the overpressure distribution, etc.

The calculation of overpressure on structural elements is performed in accordance with the international standards (UFC 3-340-02: Structures to Resist the Effects of Accidental Explosions). The explosive load can be applied both statically and dynamically.

Quasi-static analysis

Pyramidal load

The LIRA-FEM software implements analysis on explosion by quasi-static method according to DBN B.2.2-5:2023.

The explosive load is defined as static one. To collect this load, the engineer could either use the Explosion node or collect the load manually and assign it with the Pyramidal load in LIRA-CAD module.

Analysis by direct dynamic method

Generating a graph of pressure vs time

In the LIRA-FEM program, analysis on explosion is carried out by the direct dynamic method. A graph of the overpressure variation over time, accounting for both positive and negative phases, can be produced during the automatic collecting of explosive loads. For every finite element of the structure, the parameters of the direct dynamic analysis will be defined.