Tiger Cage
Brian Volmer, PhD., P.E., project engineer with Cesare, Inc., is associated with the Center for Geotechnical Engineering Science (CGES) in the Civil Engineering department at the University of Colorado Denver (UCD). Brian, under Professor Emeritus Nien-Yin Chang (director of the CGES), led the design and construction of a large-scale soil-structure interaction testing system known as the “Tiger Cage”.
The Tiger Cage is a “cage” capable of holding a soil or reinforced soil sample about 1.9 feet wide by 5.5 feet tall by 10 feet long (see Figures 1 and 2). One end of the Tiger Cage is fitted with a rotating “test wall” that is instrumented to measure lateral earth pressure with depth. The position of the wall may be held rigidly (at-rest) or manipulated to rotate away from or into the soil sample, through active or passive failure, respectively. The Cage is capable of applying 110,000 pounds of lateral force to the test wall to reach passive failure. The Tiger Cage is outfitted with a vertical loading system that allows either 60,000 pounds of concentrated loads to be applied by a hydraulic ram or uniform surcharge loading to be applied by air bags. The Tiger Cage has even been outfitted by an automated pile driver capable of delivering about 2,000 foot-pounds of driving energy.
The Tiger Cage was originally designed to validate sophisticated computational analyses of the abutments for the geosynthetic reinforced soil integrated bridge system (GRS-IBS) project located at Interstate Highway 70 (I-70) and Smith Road in Aurora, Colorado. The project was owned by the Colorado Department of Transportation (CDOT) and sponsored by the Federal Highway Administration (FHWA). Since that time the Tiger Cage has been used for various CDOT funded research.
Brian worked on the design and development of the Tiger Cage from the time the concept was presented by Professor Chang in February 2013 until the pile driver accessory was completed in August of 2017. Sponsored Tiger Cage research projects with the CGES are ongoing though and Brian has the opportunity to consult with Tiger Cage researchers from time to time.
