There is no specific command in COMPRESS labelled "blast loading". However, you can specify a user-defined wind load under the Wind Codes to simulate the pressures produced by the blast load.
It has been years since I did any work with blast loads. As I remember, the dynamic force of the blast load is transformed into an equivalent quasi-static pressure (something like what is done for wind loads). Based on this you can specify the user-defined wind load in COMPRESS. COMPRESS will then calculate the total load acting on the horizontal vessel (in both lateral and longitudinal directions) and apply to the vessel and saddles.
