Area 2

Area 2 is used for small explosive tests. This area includes a 8-m by 23-m concrete test pad with a retractable A-frame shelter and a 9-m x 9-m x 4.5-m-deep pool for underwater tests. Experimental setup for tests on the concrete pad is typically performed under the shelter for protection from weather, then the shelter is retracted for firing. Permanently installed on the test pad is the 4-kbar explosive loader, used to test 150-mm-diameter by 300-mm-long (6 in. by 12 in.) concrete or rock specimens in dynamic triaxial compression. This device uses controlled venting of explosive gases to produce pressure pulses up to 400 MPa peak (60 ksi), with rise times as short as 0.5 ms and durations as long as 100 ms. The pool is used for tests of scale models of underwater structures, calibration of UNDEX simulators, and for full-scale tests of underwater mine defeat concepts. The pool can be partially filled with sand or mud when required.

Also at Area 2 is a 150-mm-bore (6-in.) pneumatic gun for propelling 500-g projectiles at velocities up to 500 m/s. This gun can be positioned to fire over the adjacent valley or into concrete, soil, or rock targets. The instrumentation bunker houses several racks of permanently installed power supplies, amplifiers, and digital recorders and is connected via a 60-channel switchboard-type patch panel to five junction boxes distributed throughout Area 2. The walls of the bunker also include hardened ports for gas-pressure control lines, power cables, and high-speed photography.