Gantry readied for LUX lab beam placement

A temporary construction gantry has been installed in the Davis Cavern on the 4850 Level. The gantry will be used to help maneuver into place the structural steel beams that will serve as joists for the second floor of a two-story laboratory. This lab will be home to the Large Underground Xenon (LUX) dark-matter detector.

?The beams are like the joists that support the floors in your house,? Project Engineer Rick Labahn says. Only larger. Much larger. The 50 beams for the LUX lab range in size from short connectors, just a few feet long, to the four main beams?28 feet to 32 feet long?that will span the width of the Davis Cavern. The six longest beams already have been delivered to the 4850 Level, slung under the work deck in the Yates Shaft. The rest will be short enough to fit inside the Yates Shaft cage.

Ainsworth Benning Construction built the gantry, which will be even taller after another set of steel supports is added to the bottom of the device.

When lifted into place, the beams will rest on saddles secured to the walls in the cavern. They?ll form a grid that will support a steel deck for LUX?s top floor, where the experiment?s control room will be located.

A steel staircase will give access to the first floor. The LUX detector itself, a double-walled titanium cryostat filled with liquid xenon, will be lowered into a stainless steel water tank on the first floor. The 71,600-gallon tank?20 feet tall by 25 feet in diameter?will protect the detector from gamma radiation and stray neutrons. The water tank has already been delivered, in pieces, to the 4850 Level. A crew from the tank fabricator, SFI of Conway, Ark., is on site to weld the tank together. In fact, the top of the circular water tank already has been laid out on the floor of the Davis Cavern. (It?s the circle on the floor in the top left photo.)