At the Menlo Park location, Poulter Laboratory has several permanent laboratory facilities including two light gas guns, two pneumatic small-scale vehicle launchers, a torsional and two tension/compression Hopkinson bars, a 50-caliber ballistic gun, a 75 mm howitzer, a Charpy impact tester, a small-particle impact facility, a friction wear-tester, several large static-pressure vessels, an Instron testing machine, a Baldwin testing machine, and four MTS testing machines with computer control for materials and small structures testing. Poulter Laboratory maintains a walk-in explosive vault at the Menlo Park site, capable of explosive experiments with up to 200-gram charges. SRI also has a fully equipped metallography and fractography laboratory with polishing, etching, and coating facilities; several high-powered optical microscopes; and two scanning-electron microscopes.

The gas gun facility contains two helium gas guns, one with a 2.5-in. (6.35-cm) bore and length of about 7.9 ft (2.4 m), and the other with a 4-in. (10.2-cm) bore and length of over 49 ft (15 m). The smaller gun has a slotted bore, which allows both normal and slanted planar impacts, while the larger gun is smooth bored, allowing only for normal impacts. The smaller gun has a wrap-around breech (the projectile acts as the pressure valve) that can be loaded to 6000 psi (49 MPa), resulting in peak velocities of approximately 2,800 ft/s (850 m/s). The larger gun has both a wraparound breech [with a 3000-psi (20-MPa) peak pressure] that can accelerate a 1.0-kg projectile to velocities up to 2,750 ft/s (900 m/s) and a double-diaphragm breech [with a 6000-psi (41-MPa) peak pressure] that has thus far produced a maximum 4600-ft/s (1400-m/s) velocity (with 400 g projectile). The larger gun has an additional breech fixture, which allows for planar impacts at predictable velocities down to about 66 ft/s (20 m/s).

The gas guns can be used with high-speed optical photography (using a framing camera with a maximum 4.5 million frames per second), flash x-rays, or laser interferometry; in-material particle velocity or stress gage measurements (using electromagnetic foil gages or piezoresistant transducers, respectively); or terminal observations following soft recovery of the target. Target soft recovery with negligible secondary damage has been successfully performed at impact velocities up to about 400 m/s.

Poulter Laboratory maintains and operates the remote test site located about 90 minutes drive from Menlo Park. The remote test site includes several facilities for large-scale testing with high-pressures, impacts, and explosives.

Our 2.4 m diameter (8-ft), 78 m long (257-ft) shock tube is used for airblast testing of structures up to 1 m wide at pressures up to 760 kPa (110 psi). It is among the largest privately owned and operated shock tubes in the United States that has been used for contract research. The 27-m-long explosive driver section is made of 2.4-m-long AS16-70 steel tubes with wall thickness up to 44 mm (1.75 in.), accommodating a maximum pressure of 17 MPa (2500 psi). A 9-m-long floor ramp section provides a smooth transition from the driver to the 21-m flat floor section, which in turn permits the formation of a uniform shock wave in the tube before the wave reaches the 3-m test section. The test section is shock isolated from the rest of the tube to prevent disturbances from the explosion from reaching the target and associated instrumentation. This section also has a door to permit easy access and several glass-filled ports for photography. Ideal and nonideal blast wave environments are produced by detonating explosive charges distributed along the driver section and by filling different compartments in the tube with different gases. Several tests performed on scale-model structures have involved up to 60 channels of active instrumentation for pressure, acceleration, strain, displacement, and high-speed photography.

The Compact Reusable Air Blast Simulator (CRABS) is a 4-m-long by 1-m-diameter steel tube, oriented vertically and partially buried in the ground. The wall is 50 mm thick and is reinforced with 150-mm-thick steel rings over 1.2 m of its length for confining the high explosive charge that produces the simulated airblast. An instrumented soil test bed is constructed from the bottom of the tube up to the level of the charge to measure the airblast and ground shock; a soil overburden above the charge is normally used to increase the pulse duration.

The 4-kbar loader is a device to test 150-mm-diameter by 300-mm-long (6 in. by 12 in.) concrete or rock specimens in dynamic triaxial compression to a peak axial stress of 400 MPa (4 kbar = 60,000 psi) and a peak radial stress of 200 MPa. It consists of a 2-m-tall stack of 0.5-m-diameter high-strength steel plates and rings, held together with pretensioned studs around the perimeter. The loads are produced by controlled venting of explosive gases from a mixture of PETN explosive and plastic microspheres. The applied loads can have rise times as short as 0.5 ms and durations as long as 100 ms. Loads are measured with quartz piezoelectric pressure gages; specimen strains are measured with foil strain gages.

The large triaxial loader can apply static compression loads on specimens that are 0.3 m (12 in.) in diameter and 0.3 to 0.45 m (12 to 18 in.) high. The machine can apply axial pressures up to 200 MPa (29,000 psi) and radial pressures up to 150 MPa (22,000 psi). A variety of triaxial loading paths are possible.

The large-diameter impact facility uses a hydrogen-oxygen mixture explosion to accelerate a piston with an attached flyer plate that impacts the target and creates a planar uniaxial strain loading. A 100-m/s impact of a 0.6-m-diameter flyer can be achieved. In this type of loading, the stress wave in the target is completely known from first principles and thus is ideal for material testing or gage validation. The chamber provides planar impact under vacuum, rapid assembly for each experiment, definitive alignment, adequate strength for repeated use, shock isolation of the target plate and support, target design suitable for alluvial materials, and a flyer plate free rear surface for unloading tests.

The explosive test vault measures over 3-m wide by 5-m long by 3.5-m high (10-1/2 ft by 17 ft by 12 ft), with a 0.6-m by 1.4-m (2-ft by 4-1/2-ft) access hatch. Up to 200-g charges can be detonated. It includes ports for photography, instrumentation cable feedthroughs, and a remote-controlled exhaust system.