The original centrifuge was manufactured by Acutronic of France and was the first of its type. After a decade of operation, Actidyn Systemes upgraded the centrifuge to a 150 g-ton designation. The now-modified RPI Model 665-1 centrifuge machine comprises:
- Swinging platform
- Balancing counterweight
- Automatic internal balancing system
- Hydraulic rotary joints
- Optical and electrical slip rings
For more information, please read the overview.
The main attributes which characterize the centrifuge performance are:
- The nominal radius, 2.7 m, which is the distance between the center of payload and the centrifuge axis. Usable load capacity and acceleration are defined at this radius. The platform radius, 3.0 m, is the distance between the swinging basket platform and the centrifuge axis.
- Usable payload dimensions: The space available for the payload is a depth of 1,000 mm, width of 1,000 mm, height of 800 mm, and a maximum height of 1,200 mm.
- Performance envelope: The performance envelope of a centrifuge indicates the allowable levels of acceleration as a function of payload mass. For the RPI centrifuge, the do not exceed limits are: 160 g, 1.5 tons, and 150 g-tons (product of payload weight times g).
The centrifuge is equipped with a fiber optic rotary joint, 28 slip rings and wireless network, which are available to the user for data transmission. A hydraulic rotary joint is also installed with a total of 6 joint passages available to the user, two of which are rated for 3,000 psi hydraulic oil.
A forced-air ventilation system provides cooling within the enclosure, if necessary. A system of electronic locks and safety interlocks prevent machine startup if the enclosure access doors are not securely locked. A recessed portion of the access tunnel holds the variable speed motor controller and power electronics cabinets which drives the centrifuge’s electronic motors.
- Manufacturer: Acutronic, France
- Model: 665-1
- Capacity: 150 g-ton
- G-Range: 1 to 160 Gs
- Electrical Sliprings
- Signal (1 amp): 50
- Power (10 amp): 12
- Video: 2
- Fluid Joints
- Hydraulic (200 bars): 2
- Air or Water (20 bars): 4
- In-Flight Automatic Balancing System
- Imbalance Load Range: ± 4500 N
- Max. Balancing Time: 60 sec.
- Data Acquisition Channels: 128
- Length, direction bucket swings: 1000 mm
- Length, tangential direction: 1000 mm
- Typical radius to soil container base while spinning: 3.0 m
- Radiusfrom centrifuge center to pivot point: 2000 mm
- Nominal maximum platform payload mass: 1500 kg
- Nominal maximum mass of soil in a model: 800 kg
- Maximum speed for nominal maximum payload mass: 265.0 rpm
- Time required to slow from maximum to zero speed: 10 min
- Time required to increase from zero to maximum speed: 10 min
The geotechnical centrifuge at Rensselaer Polytechnic Institute was commissioned on campus in August 1989. The centrifuge facility was financed jointly by the Multidisciplinary Center for Earthquake Engineering Research (MCEER) at SUNY Buffalo, the National Science Foundation (NSF), the State of New York, and Rensselaer Polytechnic Institute.