Home Lab Resources Laminar Boxes

Laminar Boxes

2D Laminar Box

 

The 2D Laminar Container is designed specifically for use with RPI’s new 2D shaker. The container is constructed from 45 twelve-sided lightweight aluminum alloy rings arranged in a stack. Each ring is 8.9 mm (0.35 inches) in height with a 594 mm (23.4 inches) mean inside diameter, and is separated from the rings above and below by 120 roller bearings, especially designed to permit translation in the two horizontal directions with minimal frictional resistance. Relative displacements of up to 2.5 mm (0.1 inch) between rings are achievable. An adjustable restraint utilizing low-friction linear-rotary bearings is provided to maintain downward force on the ring stack. This restraint is moveable to permit testing with different numbers of rings (container height). The laminar container is designed for use at centrifuge accelerations of up to 100 g.

The design of this new RPI 2D laminar container is based upon a similar container, previously designed and manufactured by PVL Technologies for the centrifuge at the Hong Kong University of Science and Technology (HKUST). To date, that container has been used successfully in dozens of dynamic modeling experiments with the large centrifuge and biaxial shaker at HKUST. The new 2D laminar box incorporates several design enhancements, including a more rigid base plate and a modified “open top” restraint system, so as to facilitate access to the model surface by cameras and by the RPI in-flight robot.

 

Performance Specifications
Weight (empty) 129 lb (58 kg)
Weight (filled with saturated soil) 600 lb (212 kg)
Overall Height 21.5 inches (546 mm)
Overall Length 35 inches (890 mm)
Overall Width 27 inches (685 mm)
Min. Interior Diameter 23 inches (533 mm)
Max. Interior Diameter 23.8 inches (605 mm)
Mean Interior Diameter 23.4 inches (594 mm)
Max. Operating Centrifugal Acceleration 100 g

Component Specifications
Container Type Shear beam
Name 2D Laminar Box
Transparent walls? No
Container mass 58.00 kg
Max. mass of soil that can be contained 154.00 kg
Container spin on a centrifuge? Yes
Max. g rating 100.00 g
Container shape Cylindrical
Interior Dimensions
Diameter 594.00 mm
Height 546.0 mm
Top of the container Completely open

1D Large Laminar Box

The laminar box consists of a stack of up to 38 rectangular rings separated by linear roller bearings, arranged to permit relative movement between rings in the long direction with minimal friction. The rings are 9.35 mm in height. A relative displacement of up to 3.13 mm between adjacent rings is possible, and the design permits an overall shear strain up to 20%. These large strains are provided to accommodate for post liquefaction-induced soil lateral deformation. Most of the box is made of high strength aluminum alloy. The total weight of the box is 80 kg and has internal dimensions of 35.5 cm (W) × 71 cm (L) × 35.5 cm (H).

Bearings are placed between the rings to permit motion of the rings and to reduce friction. A clamp fitted with bearings is placed on top of the stack to prevent uplifting of the rings during shaking. Each ring is separated from the upper and lower adjacent rings by a total of 86 rollers. Bearing cages are used in order to maintain proper alignment and spacing of the rollers within the rings. The cages are separated from the top and bottom of each adjacent bearing by tiny Teflon pads glued to the cages. A coefficient of friction of 0.006 was measured between the rings under 8 kN

vertical load.

Component Specifications
Container Type Shear beam
Name 1D Large Laminar Box
Transparent walls? No
Container mass 80.00 kg
Container spin on a centrifuge? Yes
Max. g rating 100.00 g
Container shape Rectangular
Interior Dimensions
Length 710.00 mm
Width 355.00 mm
Height 355.0 mm
Top of the container Completely open

1D Small Laminar Box

Component Specifications
Container Type Shear beam
Name 1D Small Laminar Box
Transparent walls? No
Container spin on a centrifuge? Yes
Max. g rating 100.00 g
Container shape Rectangular
Interior Dimensions
Length 460.00 mm
Width 370.00 mm
Height 264.0 mm
Top of the container Completely open
Print Friendly