Abstract: A backstop for decelerating and trapping projectiles includes a support structure having at least one bin shielded from incoming rounds. A trapping medium, such as a resilient granular ballistic medium and a hydrated SAP gel, is disposed contiguously on an upper surface and within the bins. Bins are defined by transverse baffles spanning the width of the backstop. The baffles are preferably constructed of a non-ricochet material. Vibrations will urgetrapped rounds downwards into the bins. In embodiments, the lower surface of one or more bins declines toward either or both sides of the backstop, such that vibration urges spent rounds towards collection points along the sides of the backstop. Access ports may be provided in the backstop sidewalls proximate these collection points to allow for removal of spent rounds. The volume removed may be filtered to reclaim projectile trapping medium for reuse.

Abstract: A portable nuclear material detector generally includes a scintillating fiber radiation sensor, a light detector, a conditioning circuit, a frequency shift keying (FSK) circuit, a fast Fourier transform (FFT) circuit, an electronic controller, an amplitude spectral addition circuit, and an output device. A high voltage direct current (HVDC) source is provided to excite the light detector, while a separate power supply may be provided to power the remaining components. Portability is facilitated by locating the components of the detector within a handheld-sized housing. When bombarded by gamma particles, the radiation sensor emits light, which is detected by the light detector and converted into electrical signals. These electrical signals are then conditioned and converted to spectral lines.

Abstract: A system and method for dewatering particulate materials employs an improved dewatering probe generally including a single non-conducting pipe having a plurality of holes or slots, an anode mounted on the pipe adjacent one end of the pipe, and a cathode mounted on the pipe adjacent the opposite end of the pipe. The pipe serves as both a sonde for mounting the anode and cathode and as a well for extracting water that collects around the outside of the pipe and flows into the interior of the pipe through the holes or slots via gravitational and electro-osmotic forces. A pump may be used to extract both collected water and accumulated electrolytic gases from the pipe's interior. In embodiments, an array of guide electrodes is mounted on the pipe in addition to the anode and the cathode in order to deflect the major current flow out into the body of surrounding particulate materials. The guide electrodes also facilitate rapid depolarization of the probe.

Abstract: A modular bullet trap cover element generally includes a shell filled with a projectile trapping medium, preferably a mixture of a resilient granular ballistic medium and a hydrated super absorbent polymer (SAP) gel. The shell may be made of any of a number of fabric or polymeric materials. In embodiments, the shell includes at least two bags, an inner bag and at least one outer bag, each of which has an open end and a sealed end, connected to one another such that the outer bags may be inverted over the inner bag to cover at least a portion thereof. The modular cover element is formed by filling the inner bag with the projectile trapping medium and then inverting the outer bags to produce a multi-layer shell. In embodiments, the outer bags and inner bag are rotatably connected, permitting the outer bags to be rotated with respect to the inner bag such that bullet holes in the inner and outer bags no longer line up with each other.

Abstract: An additive for buffering a projectile trapping medium and spent projectiles trapped therein is a buffering compound formed as a low density foamed concrete block that will self-dispense via fragmentation or pulverization when subjected to incoming fire. The block combines at least one dry component selected from the group consisting of low solubility phosphate compounds, low solubility aluminum compounds, iron compounds, sulfate compounds, and calcium carbonate with a cementing material, water, and an aqueous based foam in substantially stoichiometric amounts. The aqueous based foam is added in a quantity sufficient to adjust the density of the resulting block to be non-buoyant without sinking in the projectile trapping medium. The additive may be employed in a projectile trapping medium to chemically stabilize the medium and environmentally stabilize projectiles trapped therein.

Abstract: A backstop for decelerating and trapping projectiles generally includes a support structure having an inclined surface and a projectile trapping medium disposed on the inclined surface. The projectile trapping medium may be either a resilient granular ballistic medium or a combination of a ballistic medium with a hydrated super absorbent polymer (SAP) gel. Preferably, the support structure is made of a shock absorbing, foamed, fiber-reinforced concrete, such as SACON®. In embodiments, the support structure also includes an enclosure. Additives may also be mixed into the projectile trapping medium to control alkalinity and prevent leaching of heavy metals.