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A Technical Analysis of a Proposed Theory on Tire Tread Belt Separation-Induced Axle Tramp
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 12, 2011 by SAE International in United States
Annotation ability available
Recently, papers have been published purporting to study the effect of rear axle tramp during tread separation events, and its effect on vehicle handling [1, 2]. Based on analysis and physical testing, one paper  has put forth a mathematical model which the authors claim allows vehicle designers to select shock damping values during the development process of a vehicle in order to assure that a vehicle will not experience axle tramp during tread separations. In the course of their work, “lumpy” tires (tires with rubber blocks adhered to the tire's tread) were employed to excite the axle tramp resonance, even though this method has been shown not to duplicate the physical mechanisms behind an actual tread belt separation.
This paper evaluates the theories postulated in  by first analyzing the equations behind the mathematical model presented. The model is then tested to see if it agrees with observed physical testing. Finally, the validity of the physical test methods are evaluated. Among the issues of concern were the discovery of significant algebraic and mathematical errors, questionable assumptions in the modeling of the suspension system, and procedurally flawed physical testing. This study found that the results from the referenced analysis and testing are invalid. Review of U.S. government analysis and conclusions further prove that no relationship exists between the purported suspension system damping levels and crash statistic where a tread separation is involved.
CitationTandy, D., Neal, J., Pascarella, R., and Kalis, E., "A Technical Analysis of a Proposed Theory on Tire Tread Belt Separation-Induced Axle Tramp," SAE Technical Paper 2011-01-0967, 2011, https://doi.org/10.4271/2011-01-0967.
- Ipser, J.R., Renfroe, D.A., and Roberts, A., “Solid Axle Tramp Response Near the Natural Frequency and its Effect on Vehicle Longitudinal Stability,” SAE Technical Paper 2008-01-0583, 2008, doi:10.4271/2008-01-0583.
- Renfroe, D. A., and Roberts, A.; “An Analysis of the Mechanism Causing Loss of Control During a Tire Delamination”, Paper No. 09-0209, 2009 ESV Conference.
- Dickerson, C.P., Arndt, M.W., and Arndt, S.M., “Vehicle Handling with Tire Tread Separation,” SAE Technical Paper 1999-01-0450, 1999, doi:10.4271/1999-01-0450.
- Fay, R.J., Robinette, R.D., Smith, J., Flood, T. et al., “Drag and Steering Effects from Tire Tread Belt Separation and Loss,” SAE Technical Paper 1999-01-0447, 1999, doi:10.4271/1999-01-0447.
- Tandy, D.F.Jr., Tandy, K.T., Durisek, N.J., Granat, K.J. et al., “An Analysis of Yaw Inducing Drag Forces Imparted During Tire Tread Belt Detachments,” SAE Technical Paper 2007-01-0836, 2007, doi: 10.4271/2007-01-0836.
- Holen, P. and Thorvald, B., “Aspects on Roll and Bounce Damping for Heavy Vehicles,” SAE Technical Paper 2002-01-3060, 2002, doi:10.4271/2002-01-3060.
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- Arndt, M.W., Rosenfield, M., and Arndt, S.M., “Measurement of Changes to Vehicle Handling Due to Tread-Separation-Induced Axle Tramp,” SAE Technical Paper 2006-01-1680, 2006, doi:10.4271/2006-01-1680.
- Renfroe Testing, July 2008, Unpublished Testing in the Public Domain
- Arndt, M. W., Test Numbers TSTI 0119-0122, February and March 2010
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